Makes flat_tree a proper container (#383)

Removes flat_tree::get_view()
Adds flat_tree{iterator, reverse_iterator, begin, end, rbegin, rend, data, operator[], at, front, back, size, empty}

close #362

.clang-format

@@ -0,0 +1,176 @@
+---
+Language: Cpp
+ColumnLimit: 100
+IndentWidth: 3
+BreakBeforeBraces: Custom
+BraceWrapping:
+  AfterCaseLabel: true
+  AfterClass: false
+  AfterControlStatement: false
+  AfterEnum: true
+  AfterFunction: true
+  AfterNamespace: false
+  AfterStruct: false
+  AfterUnion: false
+  AfterExternBlock: false
+  BeforeCatch: false
+  BeforeElse: false
+  IndentBraces: false
+  SplitEmptyFunction: false
+  SplitEmptyRecord: false
+  SplitEmptyNamespace: true
+AccessModifierOffset: -3
+BinPackArguments: false
+BinPackParameters: false
+AlignAfterOpenBracket: AlwaysBreak
+PointerAlignment: Left
+IncludeBlocks: Regroup
+IncludeCategories:
+  - Regex: '^<boost/redis.*>|<boost/redis/.*>'
+    Priority: -10
+    SortPriority: 1
+  - Regex: '^<boost/.*>'
+    Priority: -8
+    SortPriority: 3
+  - Regex: "^<.*"
+    Priority: -6
+    SortPriority: 5
+  - Regex: ".*"
+    Priority: -5
+    SortPriority: 4
+IndentCaseLabels: true
+AllowShortCaseLabelsOnASingleLine: true
+AllowAllArgumentsOnNextLine: false
+AllowAllParametersOfDeclarationOnNextLine: false
+AllowShortIfStatementsOnASingleLine: Never
+AllowShortLoopsOnASingleLine: false
+AlignArrayOfStructures: Left
+DerivePointerAlignment: false
+PenaltyBreakAssignment: 2000000
+PenaltyBreakBeforeFirstCallParameter: 0
+PenaltyBreakOpenParenthesis: 0
+PenaltyBreakComment: 300
+PenaltyBreakFirstLessLess: 120
+PenaltyBreakString: 1000
+PenaltyBreakTemplateDeclaration: 10
+PenaltyExcessCharacter: 1000000
+PenaltyBreakScopeResolution: 1000000
+PenaltyReturnTypeOnItsOwnLine: 200000000
+
+# Defaults (based on Google)
+AlignConsecutiveMacros: false
+AlignConsecutiveAssignments: false
+AlignConsecutiveDeclarations: false
+AlignEscapedNewlines: Left
+AlignOperands: true
+AlignTrailingComments: true
+AllowAllConstructorInitializersOnNextLine: true
+AllowShortBlocksOnASingleLine: Never
+AllowShortFunctionsOnASingleLine: All
+AllowShortLambdasOnASingleLine: Empty
+AlwaysBreakAfterDefinitionReturnType: None
+AlwaysBreakAfterReturnType: ExceptShortType
+AlwaysBreakBeforeMultilineStrings: true
+AlwaysBreakTemplateDeclarations: Yes
+BreakTemplateDeclarations: Leave
+BreakBeforeBinaryOperators: None
+BreakBeforeInheritanceComma: false
+BreakInheritanceList: BeforeColon
+BreakBeforeTernaryOperators: true
+BreakConstructorInitializersBeforeComma: true
+BreakConstructorInitializers: BeforeColon
+BreakAfterJavaFieldAnnotations: false
+BreakStringLiterals: true
+CommentPragmas: '(^ IWYU pragma:)|(^\\copydoc )|(^ ?\\n)'
+CompactNamespaces: false
+ConstructorInitializerAllOnOneLineOrOnePerLine: false
+ConstructorInitializerIndentWidth: 0
+ContinuationIndentWidth: 3
+Cpp11BracedListStyle: true
+DeriveLineEnding: true
+DisableFormat: false
+ExperimentalAutoDetectBinPacking: false
+FixNamespaceComments: true
+ForEachMacros:
+  - foreach
+  - Q_FOREACH
+  - BOOST_FOREACH
+IncludeIsMainRegex: null
+IncludeIsMainSourceRegex: ""
+IndentGotoLabels: false
+IndentPPDirectives: None
+IndentWrappedFunctionNames: false
+JavaScriptQuotes: Leave
+JavaScriptWrapImports: true
+KeepEmptyLinesAtTheStartOfBlocks: false
+MacroBlockBegin: ""
+MacroBlockEnd: ""
+MaxEmptyLinesToKeep: 1
+NamespaceIndentation: None
+ObjCBinPackProtocolList: Never
+ObjCBlockIndentWidth: 2
+ObjCSpaceAfterProperty: false
+ObjCSpaceBeforeProtocolList: true
+RawStringFormats:
+  - Language: Cpp
+    Delimiters:
+      - cc
+      - CC
+      - cpp
+      - Cpp
+      - CPP
+      - "c++"
+      - "C++"
+    CanonicalDelimiter: ""
+    BasedOnStyle: google
+  - Language: TextProto
+    Delimiters:
+      - pb
+      - PB
+      - proto
+      - PROTO
+    EnclosingFunctions:
+      - EqualsProto
+      - EquivToProto
+      - PARSE_PARTIAL_TEXT_PROTO
+      - PARSE_TEST_PROTO
+      - PARSE_TEXT_PROTO
+      - ParseTextOrDie
+      - ParseTextProtoOrDie
+    CanonicalDelimiter: ""
+    BasedOnStyle: google
+ReflowComments: false
+SortIncludes: true
+SortUsingDeclarations: false
+SpaceAfterCStyleCast: false
+SpaceAfterLogicalNot: false
+SpaceAfterTemplateKeyword: true
+SpaceBeforeAssignmentOperators: true
+SpaceBeforeCtorInitializerColon: true
+SpaceBeforeInheritanceColon: true
+SpaceBeforeParens: ControlStatements
+SpaceBeforeRangeBasedForLoopColon: true
+SpaceInEmptyBlock: true
+SpaceInEmptyParentheses: false
+SpacesBeforeTrailingComments: 2
+SpacesInAngles: false
+SpacesInConditionalStatement: false
+SpacesInContainerLiterals: true
+SpacesInCStyleCastParentheses: false
+SpacesInParentheses: false
+SpacesInSquareBrackets: false
+SpaceBeforeSquareBrackets: false
+Standard: Auto
+StatementMacros:
+  - Q_UNUSED
+  - QT_REQUIRE_VERSION
+TabWidth: 8
+UseCRLF: false
+UseTab: Never
+AlignConsecutiveShortCaseStatements:
+  Enabled: true
+  AcrossEmptyLines: false
+  AcrossComments: true
+  AlignCaseColons: false
+---
+

.github/workflows/ci.yml

@@ -21,15 +21,15 @@ jobs:
       fail-fast: false
       matrix:
         include:
-          - { toolset: msvc-14.2, os: windows-2019, generator: "Visual Studio 16 2019", cxxstd: '17', build-type: 'Debug',   build-shared-libs: 1 }
-          - { toolset: msvc-14.2, os: windows-2019, generator: "Visual Studio 16 2019", cxxstd: '17', build-type: 'Release', build-shared-libs: 0 }
+          #- { toolset: msvc-14.2, os: windows-2019, generator: "Visual Studio 16 2019", cxxstd: '17', build-type: 'Debug',   build-shared-libs: 1 }
+          #- { toolset: msvc-14.2, os: windows-2019, generator: "Visual Studio 16 2019", cxxstd: '17', build-type: 'Release', build-shared-libs: 0 }
           - { toolset: msvc-14.3, os: windows-2022, generator: "Visual Studio 17 2022", cxxstd: '20', build-type: 'Debug',   build-shared-libs: 0 }
           - { toolset: msvc-14.3, os: windows-2022, generator: "Visual Studio 17 2022", cxxstd: '20', build-type: 'Release', build-shared-libs: 1 }
     env:
       CMAKE_BUILD_PARALLEL_LEVEL: 4
     steps:
     - name: Checkout
-      uses: actions/checkout@v3
+      uses: actions/checkout@v4
 
     - name: Setup Boost
       run: python3 tools/ci.py setup-boost --source-dir=$(pwd)
@@ -100,13 +100,13 @@ jobs:
       fail-fast: false
       matrix:
         include:
-          - { toolset: msvc-14.2, os: windows-2019 }
+          #- { toolset: msvc-14.2, os: windows-2019 }
           - { toolset: msvc-14.3, os: windows-2022 }
     env:
       OPENSSL_ROOT: "C:\\Program Files\\OpenSSL"
     steps:
     - name: Checkout
-      uses: actions/checkout@v3
+      uses: actions/checkout@v4
 
     - name: Setup user-config.jam
       run: cp tools/user-config.jam "${HOMEDRIVE}${HOMEPATH}/"
@@ -131,70 +131,170 @@ jobs:
       fail-fast: false
       matrix:
         include:
-          - { toolset: gcc-11,   install: g++-11,   os: ubuntu-22.04, cxxstd: '17', build-type: 'Debug', ldflags: '' }
-          - { toolset: gcc-11,   install: g++-11,   os: ubuntu-22.04, cxxstd: '20', build-type: 'Release', ldflags: '' }
-          - { toolset: clang-11, install: clang-11, os: ubuntu-22.04, cxxstd: '17', build-type: 'Debug', ldflags: '' }
-          - { toolset: clang-11, install: clang-11, os: ubuntu-22.04, cxxstd: '20', build-type: 'Debug', ldflags: '' }
-          - { toolset: clang-13, install: clang-13, os: ubuntu-22.04, cxxstd: '17', build-type: 'Release', ldflags: '' }
-          - { toolset: clang-13, install: clang-13, os: ubuntu-22.04, cxxstd: '20', build-type: 'Release', ldflags: '' }
-          - { toolset: clang-14, install: 'clang-14 libc++-14-dev libc++abi-14-dev', os: ubuntu-22.04, cxxstd: '17', build-type: 'Debug', cxxflags: '-stdlib=libc++', ldflags: '-lc++' }
-          - { toolset: clang-14, install: 'clang-14 libc++-14-dev libc++abi-14-dev', os: ubuntu-22.04, cxxstd: '20', build-type: 'Release', cxxflags: '-stdlib=libc++', ldflags: '-lc++' }
-    runs-on: ${{ matrix.os }}
+          - toolset: gcc-11
+            install: g++-11
+            container: ubuntu:22.04
+            cxxstd: '17'
+            build-type: 'Debug'
+            ldflags: ''
+            server: "redis:7.4.5-alpine"
+
+          - toolset: gcc-11
+            install: g++-11
+            container: ubuntu:22.04
+            cxxstd: '20'
+            build-type: 'Release'
+            ldflags: ''
+            server: "redis:7.4.5-alpine"
+
+          - toolset: clang-11
+            install: clang-11
+            container: ubuntu:22.04
+            cxxstd: '17'
+            build-type: 'Debug'
+            ldflags: ''
+            server: "redis:7.4.5-alpine"
+
+          - toolset: clang-11
+            install: clang-11
+            container: ubuntu:22.04
+            cxxstd: '20'
+            build-type: 'Debug'
+            ldflags: ''
+            server: "redis:7.4.5-alpine"
+
+          - toolset: clang-13
+            install: clang-13
+            container: ubuntu:22.04
+            cxxstd: '17'
+            build-type: 'Release'
+            ldflags: ''
+            server: "redis:8.2.1-alpine"
+
+          - toolset: clang-13
+            install: clang-13
+            container: ubuntu:22.04
+            cxxstd: '20'
+            build-type: 'Release'
+            ldflags: ''
+            server: "redis:8.2.1-alpine"
+
+          - toolset: clang-14
+            install: 'clang-14 libc++-14-dev libc++abi-14-dev'
+            container: ubuntu:22.04
+            cxxstd: '17'
+            build-type: 'Debug'
+            cxxflags: '-stdlib=libc++'
+            ldflags: '-lc++'
+            server: "redis:8.2.1-alpine"
+
+          - toolset: clang-14
+            install: 'clang-14 libc++-14-dev libc++abi-14-dev'
+            container: ubuntu:22.04
+            cxxstd: '20'
+            build-type: 'Release'
+            cxxflags: '-stdlib=libc++'
+            ldflags: '-lc++'
+            server: "redis:8.2.1-alpine"
+          
+          - toolset: clang-19
+            install: 'clang-19'
+            container: ubuntu:24.04
+            cxxstd: '23'
+            build-type: 'Debug'
+            cxxflags: '-fsanitize=address -fsanitize=undefined -fno-sanitize-recover=all'
+            ldflags: '-fsanitize=address -fsanitize=undefined'
+            server: "redis:8.2.1-alpine"
+
+          - toolset: gcc-14
+            install: 'g++-14'
+            container: ubuntu:24.04
+            cxxstd: '23'
+            build-type: 'Debug'
+            cxxflags: '-DBOOST_ASIO_DISABLE_LOCAL_SOCKETS=1' # If a system had no UNIX socket support, we build correctly
+            server: "valkey/valkey:8.1.3-alpine"
+          
+          - toolset: gcc-14
+            install: 'g++-14'
+            container: ubuntu:24.04
+            cxxstd: '23'
+            build-type: 'Debug'
+            cxxflags: '-fsanitize=address -fsanitize=undefined -fno-sanitize-recover=all'
+            ldflags: '-fsanitize=address -fsanitize=undefined'
+            server: "valkey/valkey:8.1.3-alpine"
+
+    runs-on: ubuntu-latest
     env:
       CXXFLAGS: ${{matrix.cxxflags}} -Wall -Wextra
       LDFLAGS:  ${{matrix.ldflags}}
       CMAKE_BUILD_PARALLEL_LEVEL: 4
+    
     steps:
     - name: Checkout
-      uses: actions/checkout@v3
-
+      uses: actions/checkout@v4
+    
+    - name: Set up the required containers
+      run: |
+        BUILDER_IMAGE=${{ matrix.container }} SERVER_IMAGE=${{ matrix.server }} docker compose -f tools/docker-compose.yml up -d --wait || (docker compose logs; exit 1)
+      
     - name: Install dependencies
-      run: sudo apt-get -y install cmake protobuf-compiler redis-server python3 ${{ matrix.install }}
+      run: |
+        docker exec builder apt-get update
+        docker exec builder apt-get -y --no-install-recommends install \
+          git \
+          g++ \
+          libssl-dev \
+          make \
+          ca-certificates \
+          cmake \
+          protobuf-compiler \
+          python3 \
+          ${{ matrix.install }}
 
     - name: Setup Boost
-      run: ./tools/ci.py setup-boost --source-dir=$(pwd)
+      run: docker exec builder /boost-redis/tools/ci.py setup-boost --source-dir=/boost-redis
 
     - name: Build a Boost distribution using B2
       run: |
-        ./tools/ci.py build-b2-distro \
+        docker exec builder /boost-redis/tools/ci.py build-b2-distro \
           --toolset ${{ matrix.toolset }}
 
     - name: Build a Boost distribution using CMake
       run: |
-        ./tools/ci.py build-cmake-distro \
+        docker exec builder /boost-redis/tools/ci.py build-cmake-distro \
           --build-type ${{ matrix.build-type }} \
           --cxxstd ${{ matrix.cxxstd }} \
           --toolset ${{ matrix.toolset }}
 
     - name: Build the project tests
       run: |
-        ./tools/ci.py build-cmake-standalone-tests \
+        docker exec builder /boost-redis/tools/ci.py build-cmake-standalone-tests \
           --build-type ${{ matrix.build-type }} \
           --cxxstd ${{ matrix.cxxstd }} \
           --toolset ${{ matrix.toolset }}
   
     - name: Run the project tests
       run: |
-        ./tools/ci.py run-cmake-standalone-tests \
+        docker exec builder /boost-redis/tools/ci.py run-cmake-standalone-tests \
           --build-type ${{ matrix.build-type }}
 
     - name: Run add_subdirectory tests
       run: |
-        ./tools/ci.py run-cmake-add-subdirectory-tests \
+        docker exec builder /boost-redis/tools/ci.py run-cmake-add-subdirectory-tests \
           --build-type ${{ matrix.build-type }} \
           --cxxstd ${{ matrix.cxxstd }} \
           --toolset ${{ matrix.toolset }}
 
     - name: Run find_package tests with the built cmake distribution
       run: |
-        ./tools/ci.py run-cmake-find-package-tests \
+        docker exec builder /boost-redis/tools/ci.py run-cmake-find-package-tests \
           --build-type ${{ matrix.build-type }} \
           --cxxstd ${{ matrix.cxxstd }} \
           --toolset ${{ matrix.toolset }}
 
     - name: Run find_package tests with the built b2 distribution
       run: |
-        ./tools/ci.py run-cmake-b2-find-package-tests \
+        docker exec builder /boost-redis/tools/ci.py run-cmake-b2-find-package-tests \
           --build-type ${{ matrix.build-type }} \
           --cxxstd ${{ matrix.cxxstd }} \
           --toolset ${{ matrix.toolset }}
@@ -209,15 +309,32 @@ jobs:
       fail-fast: false
       matrix:
         include:
-          - { toolset: gcc-11,   install: g++-11,   cxxstd: "11,17,20" } # Having C++11 shouldn't break the build
-          - { toolset: clang-14, install: clang-14, cxxstd: "17,20" }
-    runs-on: ubuntu-22.04
+          - toolset: gcc-11
+            install: g++-11
+            cxxstd: "11,17,20" # Having C++11 shouldn't break the build
+            os: ubuntu-latest
+            container: ubuntu:22.04
+          - toolset: clang-14
+            install: clang-14
+            os: ubuntu-latest
+            container: ubuntu:22.04
+            cxxstd: "17,20"
+    runs-on: ${{ matrix.os }}
+    container: ${{matrix.container}}
     steps:
     - name: Checkout
-      uses: actions/checkout@v3
+      uses: actions/checkout@v4
+
+    - name: Setup container environment
+      if: matrix.container
+      run: |
+        apt-get update
+        apt-get -y install sudo python3 git g++ libssl-dev
 
     - name: Install dependencies
-      run: sudo apt-get -y install python3 ${{ matrix.install }}
+      run: |
+        sudo apt-get update
+        sudo apt-get -y install python3 ${{ matrix.install }}
 
     - name: Setup Boost
       run: ./tools/ci.py setup-boost --source-dir=$(pwd)
@@ -228,3 +345,24 @@ jobs:
           --toolset ${{ matrix.toolset }} \
           --cxxstd ${{ matrix.cxxstd }} \
           --variant debug,release
+
+  # Checks that we don't have any errors in docs
+  check-docs:
+    name: Check docs
+    defaults:
+      run:
+        shell: bash
+
+    runs-on: ubuntu-latest
+    steps:
+    - name: Checkout
+      uses: actions/checkout@v4
+
+    - name: Setup Boost
+      run: ./tools/ci.py setup-boost --source-dir=$(pwd)
+    
+    - name: Build docs
+      run: |
+        cd ~/boost-root
+        ./b2 libs/redis/doc
+        [ -f ~/boost-root/libs/redis/doc/html/index.html ]

.github/workflows/coverage.yml

@@ -1,51 +0,0 @@
-name: Coverage
-
-on:
-  push:
-    branches:
-      - develop
-
-jobs:
-  posix:
-    defaults:
-      run:
-        shell: bash
-
-    runs-on: ubuntu-22.04
-    env:
-      CXX: g++-11
-      CXXFLAGS: -g -O0 -std=c++20 --coverage -fkeep-inline-functions -fkeep-static-functions
-      LDFLAGS: --coverage
-      CMAKE_BUILD_PARALLEL_LEVEL: 4
-    steps:
-    - name: Checkout
-      uses: actions/checkout@v3
-
-    - name: Install dependencies
-      run: sudo apt-get --no-install-recommends -y install cmake lcov g++-11 redis-server python3 libgd-perl
-    
-    - name: Setup Boost
-      run: ./tools/ci.py setup-boost --source-dir=$(pwd)
-    
-    - name: Build Boost
-      run: ./tools/ci.py build-b2-distro --toolset=gcc-11
-    
-    # Having our library there confuses the coverage reports
-    - name: Remove Boost.Redis from the b2 distro
-      run: rm -rf ~/boost-b2-distro/include/boost/redis
-
-    - name: Run CMake
-      run: cmake -DCMAKE_PREFIX_PATH=$HOME/boost-b2-distro --preset coverage .
-
-    - name: Build
-      run: cmake --build --preset coverage
-
-    - name: Test
-      run: ctest --preset coverage
-
-    - name: Make the coverage file
-      run: cmake --build --preset coverage --target coverage
-
-    - name: Upload to codecov
-      run: |
-        bash <(curl -s https://codecov.io/bash) -f ./build/coverage/coverage.info

CMakeLists.txt

@@ -19,13 +19,77 @@ target_compile_features(boost_redis INTERFACE cxx_std_17)
 
 # Dependencies
 if (BOOST_REDIS_MAIN_PROJECT)
-  # If we're the root project, error if a dependency is not found
-  find_package(Boost 1.83 REQUIRED COMPONENTS headers)
+  # TODO: Understand why we have to list all dependencies below
+  # instead of
+  #set(BOOST_INCLUDE_LIBRARIES redis)
+  #set(BOOST_EXCLUDE_LIBRARIES redis)
+  #add_subdirectory(../.. boostorg/boost EXCLUDE_FROM_ALL)
+
+  set(deps
+    system
+    assert
+    config
+    throw_exception
+    asio
+    variant2
+    mp11
+    winapi
+    predef
+    align
+    context
+    core
+    static_assert
+    pool
+    date_time
+    smart_ptr
+    exception
+    integer
+    move
+    type_traits
+    algorithm
+    utility
+    io
+    lexical_cast
+    numeric/conversion
+    mpl
+    range
+    tokenizer
+    tuple
+    array
+    bind
+    concept_check
+    function
+    iterator
+    regex
+    unordered
+    preprocessor
+    container
+    conversion
+    container_hash
+    detail
+    optional
+    function_types
+    fusion
+    intrusive
+    describe
+    typeof
+    functional
+    test
+    json
+    endian
+    compat
+  )
+
+  foreach(dep IN LISTS deps)
+    add_subdirectory(../${dep} boostorg/${dep})
+  endforeach()
+
   find_package(Threads REQUIRED)
   find_package(OpenSSL REQUIRED)
   target_link_libraries(boost_redis
     INTERFACE
-      Boost::headers
+      Boost::system
+      Boost::asio
       Threads::Threads
       OpenSSL::Crypto
       OpenSSL::SSL

CMakePresets.json

@@ -1,178 +0,0 @@
-{
-  "version": 2,
-  "cmakeMinimumRequired": {
-    "major": 3,
-    "minor": 14,
-    "patch": 0
-  },
-  "configurePresets": [
-    {
-      "name": "cmake-pedantic",
-      "hidden": true,
-      "warnings": {
-        "dev": true,
-        "deprecated": true,
-        "uninitialized": false,
-        "unusedCli": true,
-        "systemVars": false
-      },
-      "errors": {
-        "dev": true,
-        "deprecated": true
-      }
-    },
-    {
-      "name": "coverage",
-      "generator": "Unix Makefiles",
-      "hidden": false,
-      "inherits": ["cmake-pedantic"],
-      "binaryDir": "${sourceDir}/build/coverage",
-      "cacheVariables": {
-        "CMAKE_BUILD_TYPE": "Coverage",
-        "CMAKE_CXX_EXTENSIONS": "OFF",
-        "CMAKE_CXX_FLAGS": "-Wall -Wextra",
-        "CMAKE_CXX_FLAGS_COVERAGE": "-Og -g --coverage -fkeep-inline-functions -fkeep-static-functions",
-        "CMAKE_CXX_STANDARD_REQUIRED": "ON",
-        "CMAKE_EXE_LINKER_FLAGS_COVERAGE": "--coverage",
-        "CMAKE_SHARED_LINKER_FLAGS_COVERAGE": "--coverage",
-        "PROJECT_BINARY_DIR": "${sourceDir}/build/coverage",
-        "COVERAGE_HTML_COMMAND": ""
-      }
-    },
-    {
-      "name": "g++-11",
-      "generator": "Unix Makefiles",
-      "hidden": false,
-      "inherits": ["cmake-pedantic"],
-      "binaryDir": "${sourceDir}/build/g++-11",
-      "cacheVariables": {
-        "CMAKE_BUILD_TYPE": "Debug",
-        "CMAKE_CXX_EXTENSIONS": "OFF",
-        "CMAKE_CXX_FLAGS": "-Wall -Wextra -fsanitize=address",
-        "CMAKE_CXX_COMPILER": "g++-11",
-        "CMAKE_SHARED_LINKER_FLAGS": "-fsanitize=address",
-        "CMAKE_CXX_STANDARD_REQUIRED": "ON",
-        "PROJECT_BINARY_DIR": "${sourceDir}/build/g++-11"
-      }
-    },
-    {
-      "name": "g++-11-release",
-      "generator": "Unix Makefiles",
-      "hidden": false,
-      "inherits": ["cmake-pedantic"],
-      "binaryDir": "${sourceDir}/build/g++-11-release",
-      "cacheVariables": {
-        "CMAKE_BUILD_TYPE": "Release",
-        "CMAKE_CXX_EXTENSIONS": "OFF",
-        "CMAKE_CXX_FLAGS": "-Wall -Wextra",
-        "CMAKE_CXX_COMPILER": "g++-11",
-        "CMAKE_SHARED_LINKER_FLAGS": "",
-        "CMAKE_CXX_STANDARD_REQUIRED": "ON",
-        "PROJECT_BINARY_DIR": "${sourceDir}/build/g++-11-release"
-      }
-    },
-    {
-      "name": "clang++-13",
-      "generator": "Unix Makefiles",
-      "hidden": false,
-      "inherits": ["cmake-pedantic"],
-      "binaryDir": "${sourceDir}/build/clang++-13",
-      "cacheVariables": {
-        "CMAKE_BUILD_TYPE": "Debug",
-        "CMAKE_CXX_EXTENSIONS": "OFF",
-        "CMAKE_CXX_FLAGS": "-Wall -Wextra -fsanitize=address",
-        "CMAKE_CXX_COMPILER": "clang++-13",
-        "CMAKE_SHARED_LINKER_FLAGS": "-fsanitize=address",
-        "CMAKE_CXX_STANDARD_REQUIRED": "ON",
-        "PROJECT_BINARY_DIR": "${sourceDir}/build/clang++-13"
-      }
-    },
-    {
-      "name": "clang++-14",
-      "generator": "Unix Makefiles",
-      "hidden": false,
-      "inherits": ["cmake-pedantic"],
-      "binaryDir": "${sourceDir}/build/clang++-14",
-      "cacheVariables": {
-        "CMAKE_BUILD_TYPE": "Debug",
-        "CMAKE_CXX_EXTENSIONS": "OFF",
-        "CMAKE_CXX_FLAGS": "-Wall -Wextra -fsanitize=address",
-        "CMAKE_CXX_COMPILER": "clang++-14",
-        "CMAKE_SHARED_LINKER_FLAGS": "-fsanitize=address",
-        "CMAKE_CXX_STANDARD_REQUIRED": "ON",
-        "PROJECT_BINARY_DIR": "${sourceDir}/build/clang++-14"
-      }
-    },
-    {
-      "name": "libc++-14-cpp17",
-      "generator": "Unix Makefiles",
-      "hidden": false,
-      "inherits": ["cmake-pedantic"],
-      "binaryDir": "${sourceDir}/build/libc++-14-cpp17",
-      "cacheVariables": {
-        "CMAKE_BUILD_TYPE": "Debug",
-        "CMAKE_CXX_EXTENSIONS": "OFF",
-        "CMAKE_CXX_FLAGS": "-Wall -Wextra -stdlib=libc++ -std=c++17",
-        "CMAKE_EXE_LINKER_FLAGS": "-lc++",
-        "CMAKE_CXX_COMPILER": "clang++-14",
-        "CMAKE_SHARED_LINKER_FLAGS": "",
-        "CMAKE_CXX_STANDARD_REQUIRED": "ON",
-        "PROJECT_BINARY_DIR": "${sourceDir}/build/libc++-14-cpp17"
-      }
-    },
-    {
-      "name": "libc++-14-cpp20",
-      "generator": "Unix Makefiles",
-      "hidden": false,
-      "inherits": ["cmake-pedantic"],
-      "binaryDir": "${sourceDir}/build/libc++-14-cpp20",
-      "cacheVariables": {
-        "CMAKE_BUILD_TYPE": "Debug",
-        "CMAKE_CXX_EXTENSIONS": "OFF",
-        "CMAKE_CXX_FLAGS": "-Wall -Wextra -stdlib=libc++ -std=c++17",
-        "CMAKE_EXE_LINKER_FLAGS": "-lc++",
-        "CMAKE_CXX_COMPILER": "clang++-14",
-        "CMAKE_SHARED_LINKER_FLAGS": "",
-        "CMAKE_CXX_STANDARD_REQUIRED": "ON",
-        "PROJECT_BINARY_DIR": "${sourceDir}/build/libc++-14-cpp20"
-      }
-    },
-    {
-      "name": "clang-tidy",
-      "generator": "Unix Makefiles",
-      "hidden": false,
-      "inherits": ["g++-11"],
-      "binaryDir": "${sourceDir}/build/clang-tidy",
-      "cacheVariables": {
-        "CMAKE_CXX_CLANG_TIDY": "clang-tidy;--header-filter=${sourceDir}/include/*",
-        "CMAKE_CXX_STANDARD": "20"
-      }
-    }
-  ],
-  "buildPresets": [
-     { "name": "coverage", "configurePreset": "coverage" },
-     { "name": "g++-11", "configurePreset": "g++-11" },
-     { "name": "g++-11-release", "configurePreset": "g++-11-release" },
-     { "name": "clang++-13", "configurePreset": "clang++-13" },
-     { "name": "clang++-14", "configurePreset": "clang++-14" },
-     { "name": "libc++-14-cpp17", "configurePreset": "libc++-14-cpp17" },
-     { "name": "libc++-14-cpp20", "configurePreset": "libc++-14-cpp20" },
-     { "name": "clang-tidy", "configurePreset": "clang-tidy" }
-  ],
-  "testPresets": [
-     {
-       "name": "test",
-       "hidden": true,
-       "output": {"outputOnFailure": true},
-       "execution": {"noTestsAction": "error", "stopOnFailure": true}
-     },
-     { "name": "coverage",        "configurePreset": "coverage",         "inherits": ["test"] },
-     { "name": "g++-11",          "configurePreset": "g++-11",           "inherits": ["test"] },
-     { "name": "g++-11-release",  "configurePreset": "g++-11-release",   "inherits": ["test"] },
-     { "name": "clang++-13",      "configurePreset": "clang++-13",       "inherits": ["test"] },
-     { "name": "clang++-14",      "configurePreset": "clang++-14",       "inherits": ["test"] },
-     { "name": "libc++-14-cpp17", "configurePreset": "libc++-14-cpp17",  "inherits": ["test"] },
-     { "name": "libc++-14-cpp20", "configurePreset": "libc++-14-cpp20",  "inherits": ["test"] },
-     { "name": "clang-tidy",      "configurePreset": "clang-tidy",       "inherits": ["test"] }
-  ]
-}

benchmarks/cpp/asio/echo_server_client.cpp

@@ -4,8 +4,9 @@
  * accompanying file LICENSE.txt)
  */
 
-#include <iostream>
 #include <boost/asio.hpp>
+
+#include <iostream>
 #if defined(BOOST_ASIO_HAS_CO_AWAIT)
 
 namespace net = boost::asio;
@@ -26,9 +27,9 @@ auto example(boost::asio::ip::tcp::endpoint ep, std::string msg, int n) -> net::
       auto dbuffer = net::dynamic_buffer(buffer);
       for (int i = 0; i < n; ++i) {
          co_await net::async_write(socket, net::buffer(msg));
-         auto n = co_await net::async_read_until(socket, dbuffer, "\n");
+         auto bytes_read = co_await net::async_read_until(socket, dbuffer, "\n");
          //std::printf("> %s", buffer.data());
-         dbuffer.consume(n);
+         dbuffer.consume(bytes_read);
       }
 
       //std::printf("Ok: %s", msg.data());
@@ -62,6 +63,10 @@ int main(int argc, char* argv[])
       std::cerr << e.what() << std::endl;
    }
 }
-#else // defined(BOOST_ASIO_HAS_CO_AWAIT)
-auto main() -> int {std::cout << "Requires coroutine support." << std::endl; return 1;}
-#endif // defined(BOOST_ASIO_HAS_CO_AWAIT)
+#else   // defined(BOOST_ASIO_HAS_CO_AWAIT)
+auto main() -> int
+{
+   std::cout << "Requires coroutine support." << std::endl;
+   return 1;
+}
+#endif  // defined(BOOST_ASIO_HAS_CO_AWAIT)

benchmarks/cpp/asio/echo_server_direct.cpp

@@ -8,9 +8,10 @@
 // file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
 //
 
+#include <boost/asio.hpp>
+
 #include <cstdio>
 #include <iostream>
-#include <boost/asio.hpp>
 #if defined(BOOST_ASIO_HAS_CO_AWAIT)
 
 namespace net = boost::asio;
@@ -27,37 +28,41 @@ constexpr net::use_awaitable_t<executor_type> use_awaitable;
 
 awaitable_type echo(tcp_socket socket)
 {
-  try {
-     char data[1024];
-     for (;;) {
-        std::size_t n = co_await socket.async_read_some(net::buffer(data), use_awaitable);
-        co_await async_write(socket, net::buffer(data, n), use_awaitable);
-     }
-  } catch (std::exception const&) {
-     //std::printf("echo Exception: %s\n", e.what());
-  }
+   try {
+      char data[1024];
+      for (;;) {
+         std::size_t n = co_await socket.async_read_some(net::buffer(data), use_awaitable);
+         co_await async_write(socket, net::buffer(data, n), use_awaitable);
+      }
+   } catch (std::exception const&) {
+      //std::printf("echo Exception: %s\n", e.what());
+   }
 }
 
 awaitable_type listener()
 {
-  auto ex = co_await this_coro::executor;
-  tcp_acceptor acceptor(ex, {tcp::v4(), 55555});
-  for (;;) {
-     tcp_socket socket = co_await acceptor.async_accept(use_awaitable);
-     co_spawn(ex, echo(std::move(socket)), detached);
-  }
+   auto ex = co_await this_coro::executor;
+   tcp_acceptor acceptor(ex, {tcp::v4(), 55555});
+   for (;;) {
+      tcp_socket socket = co_await acceptor.async_accept(use_awaitable);
+      co_spawn(ex, echo(std::move(socket)), detached);
+   }
 }
 
 int main()
 {
-  try {
-     net::io_context io_context{BOOST_ASIO_CONCURRENCY_HINT_UNSAFE_IO};
-     co_spawn(io_context, listener(), detached);
-     io_context.run();
-  } catch (std::exception const& e) {
-     std::printf("Exception: %s\n", e.what());
-  }
+   try {
+      net::io_context io_context{BOOST_ASIO_CONCURRENCY_HINT_UNSAFE_IO};
+      co_spawn(io_context, listener(), detached);
+      io_context.run();
+   } catch (std::exception const& e) {
+      std::printf("Exception: %s\n", e.what());
+   }
 }
-#else // defined(BOOST_ASIO_HAS_CO_AWAIT)
-auto main() -> int {std::cout << "Requires coroutine support." << std::endl; return 1;}
-#endif // defined(BOOST_ASIO_HAS_CO_AWAIT)
+#else   // defined(BOOST_ASIO_HAS_CO_AWAIT)
+auto main() -> int
+{
+   std::cout << "Requires coroutine support." << std::endl;
+   return 1;
+}
+#endif  // defined(BOOST_ASIO_HAS_CO_AWAIT)

build.jam

@@ -0,0 +1,28 @@
+# Copyright René Ferdinand Rivera Morell 2024
+# Distributed under the Boost Software License, Version 1.0.
+# (See accompanying file LICENSE_1_0.txt or copy at
+# http://www.boost.org/LICENSE_1_0.txt)
+
+require-b2 5.2 ;
+
+constant boost_dependencies :
+    /boost/asio//boost_asio
+    /boost/assert//boost_assert
+    /boost/core//boost_core
+    /boost/mp11//boost_mp11
+    /boost/system//boost_system
+    /boost/throw_exception//boost_throw_exception ;
+
+project /boost/redis
+    : common-requirements
+        <include>include
+    ;
+
+explicit
+    [ alias boost_redis : : : : <library>$(boost_dependencies) ]
+    [ alias all : boost_redis test ]
+    ;
+
+call-if : boost-library redis
+    ;
+

doc/CMakeLists.txt

@@ -0,0 +1,26 @@
+#
+# Copyright (c) 2025 Ruben Perez Hidalgo (rubenperez038 at gmail dot com)
+#
+# Distributed under the Boost Software License, Version 1.0. (See accompanying
+# file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+#
+
+# Root CMakeLists.txt so MrDocs knows how to build our code
+cmake_minimum_required(VERSION 3.8...3.22)
+
+# Project
+project(boost_redis_mrdocs LANGUAGES CXX)
+
+# MrDocs forces CMAKE_EXPORT_COMPILE_COMMANDS=ON, incorrectly
+# causing all targets to be dumped to the compilation database.
+# Disable this setting so we can set EXPORT_COMPILE_COMMANDS
+# only to our target of interest
+set(CMAKE_EXPORT_COMPILE_COMMANDS OFF)
+
+# Add Boost
+add_subdirectory($ENV{BOOST_SRC_DIR} deps/boost)
+
+# Add the target for mrdocs to analyze
+add_executable(mrdocs mrdocs.cpp)
+target_link_libraries(mrdocs PRIVATE Boost::redis)
+set_target_properties(mrdocs PROPERTIES EXPORT_COMPILE_COMMANDS ON)

doc/DoxygenLayout.xml

@@ -1,226 +0,0 @@
-<doxygenlayout version="1.0">
-  <!-- Generated by doxygen 1.9.1 -->
-  <!-- Navigation index tabs for HTML output -->
-  <navindex>
-    <tab type="mainpage" visible="yes" title="Contents"/>
-    <tab type="pages" visible="yes" title="" intro=""/>
-    <tab type="modules" visible="no" title="Reference" intro=""/>
-    <tab type="namespaces" visible="no" title="">
-      <tab type="namespacelist" visible="yes" title="" intro=""/>
-      <tab type="namespacemembers" visible="yes" title="" intro=""/>
-    </tab>
-    <tab type="interfaces" visible="no" title="">
-      <tab type="interfacelist" visible="yes" title="" intro=""/>
-      <tab type="interfaceindex" visible="$ALPHABETICAL_INDEX" title=""/> 
-      <tab type="interfacehierarchy" visible="yes" title="" intro=""/>
-    </tab>
-    <tab type="classes" visible="no" title="">
-      <tab type="classlist" visible="no" title="" intro=""/>
-      <tab type="classindex" visible="$ALPHABETICAL_INDEX" title=""/> 
-      <tab type="hierarchy" visible="no" title="" intro=""/>
-      <tab type="classmembers" visible="no" title="" intro=""/>
-    </tab>
-    <tab type="structs" visible="no" title="">
-      <tab type="structlist" visible="no" title="" intro=""/>
-      <tab type="structindex" visible="$ALPHABETICAL_INDEX" title=""/> 
-    </tab>
-    <tab type="exceptions" visible="no" title="">
-      <tab type="exceptionlist" visible="no" title="" intro=""/>
-      <tab type="exceptionindex" visible="$ALPHABETICAL_INDEX" title=""/> 
-      <tab type="exceptionhierarchy" visible="yes" title="" intro=""/>
-    </tab>
-    <tab type="files" visible="no" title="">
-      <tab type="filelist" visible="no" title="" intro=""/>
-      <tab type="globals" visible="no" title="" intro=""/>
-    </tab>
-    <tab type="examples" visible="yes" title="" intro=""/>  
-  </navindex>
-
-  <!-- Layout definition for a class page -->
-  <class>
-    <briefdescription visible="yes"/>
-    <includes visible="$SHOW_INCLUDE_FILES"/>
-    <inheritancegraph visible="$CLASS_GRAPH"/>
-    <collaborationgraph visible="$COLLABORATION_GRAPH"/>
-    <memberdecl>
-      <nestedclasses visible="yes" title=""/>
-      <publictypes title=""/>
-      <services title=""/>
-      <interfaces title=""/>
-      <publicslots title=""/>
-      <signals title=""/>
-      <publicmethods title=""/>
-      <publicstaticmethods title=""/>
-      <publicattributes title=""/>
-      <publicstaticattributes title=""/>
-      <protectedtypes title=""/>
-      <protectedslots title=""/>
-      <protectedmethods title=""/>
-      <protectedstaticmethods title=""/>
-      <protectedattributes title=""/>
-      <protectedstaticattributes title=""/>
-      <packagetypes title=""/>
-      <packagemethods title=""/>
-      <packagestaticmethods title=""/>
-      <packageattributes title=""/>
-      <packagestaticattributes title=""/>
-      <properties title=""/>
-      <events title=""/>
-      <privatetypes title=""/>
-      <privateslots title=""/>
-      <privatemethods title=""/>
-      <privatestaticmethods title=""/>
-      <privateattributes title=""/>
-      <privatestaticattributes title=""/>
-      <friends title=""/>
-      <related title="" subtitle=""/>
-      <membergroups visible="yes"/>
-    </memberdecl>
-    <detaileddescription title=""/>
-    <memberdef>
-      <inlineclasses title=""/>
-      <typedefs title=""/>
-      <enums title=""/>
-      <services title=""/>
-      <interfaces title=""/>
-      <constructors title=""/>
-      <functions title=""/>
-      <related title=""/>
-      <variables title=""/>
-      <properties title=""/>
-      <events title=""/>
-    </memberdef>
-    <allmemberslink visible="yes"/>
-    <usedfiles visible="$SHOW_USED_FILES"/>
-    <authorsection visible="yes"/>
-  </class>
-
-  <!-- Layout definition for a namespace page -->
-  <namespace>
-    <briefdescription visible="yes"/>
-    <memberdecl>
-      <nestednamespaces visible="yes" title=""/>
-      <constantgroups visible="yes" title=""/>
-      <interfaces visible="yes" title=""/>
-      <classes visible="yes" title=""/>
-      <structs visible="yes" title=""/>
-      <exceptions visible="yes" title=""/>
-      <typedefs title=""/>
-      <sequences title=""/>
-      <dictionaries title=""/>
-      <enums title=""/>
-      <functions title=""/>
-      <variables title=""/>
-      <membergroups visible="yes"/>
-    </memberdecl>
-    <detaileddescription title=""/>
-    <memberdef>
-      <inlineclasses title=""/>
-      <typedefs title=""/>
-      <sequences title=""/>
-      <dictionaries title=""/>
-      <enums title=""/>
-      <functions title=""/>
-      <variables title=""/>
-    </memberdef>
-    <authorsection visible="yes"/>
-  </namespace>
-
-  <!-- Layout definition for a file page -->
-  <file>
-    <briefdescription visible="yes"/>
-    <includes visible="$SHOW_INCLUDE_FILES"/>
-    <includegraph visible="$INCLUDE_GRAPH"/>
-    <includedbygraph visible="$INCLUDED_BY_GRAPH"/>
-    <sourcelink visible="yes"/>
-    <memberdecl>
-      <interfaces visible="yes" title=""/>
-      <classes visible="yes" title=""/>
-      <structs visible="yes" title=""/>
-      <exceptions visible="yes" title=""/>
-      <namespaces visible="yes" title=""/>
-      <constantgroups visible="yes" title=""/>
-      <defines title=""/>
-      <typedefs title=""/>
-      <sequences title=""/>
-      <dictionaries title=""/>
-      <enums title=""/>
-      <functions title=""/>
-      <variables title=""/>
-      <membergroups visible="yes"/>
-    </memberdecl>
-    <detaileddescription title=""/>
-    <memberdef>
-      <inlineclasses title=""/>
-      <defines title=""/>
-      <typedefs title=""/>
-      <sequences title=""/>
-      <dictionaries title=""/>
-      <enums title=""/>
-      <functions title=""/>
-      <variables title=""/>
-    </memberdef>
-    <authorsection/>
-  </file>
-
-  <!-- Layout definition for a group page -->
-  <group>
-    <briefdescription visible="yes"/>
-    <groupgraph visible="$GROUP_GRAPHS"/>
-    <memberdecl>
-      <nestedgroups visible="yes" title=""/>
-      <dirs visible="yes" title=""/>
-      <files visible="yes" title=""/>
-      <namespaces visible="yes" title=""/>
-      <classes visible="yes" title=""/>
-      <defines title=""/>
-      <typedefs title=""/>
-      <sequences title=""/>
-      <dictionaries title=""/>
-      <enums title=""/>
-      <enumvalues title=""/>
-      <functions title=""/>
-      <variables title=""/>
-      <signals title=""/>
-      <publicslots title=""/>
-      <protectedslots title=""/>
-      <privateslots title=""/>
-      <events title=""/>
-      <properties title=""/>
-      <friends title=""/>
-      <membergroups visible="yes"/>
-    </memberdecl>
-    <detaileddescription title=""/>
-    <memberdef>
-      <pagedocs/>
-      <inlineclasses title=""/>
-      <defines title=""/>
-      <typedefs title=""/>
-      <sequences title=""/>
-      <dictionaries title=""/>
-      <enums title=""/>
-      <enumvalues title=""/>
-      <functions title=""/>
-      <variables title=""/>
-      <signals title=""/>
-      <publicslots title=""/>
-      <protectedslots title=""/>
-      <privateslots title=""/>
-      <events title=""/>
-      <properties title=""/>
-      <friends title=""/>
-    </memberdef>
-    <authorsection visible="yes"/>
-  </group>
-
-  <!-- Layout definition for a directory page -->
-  <directory>
-    <briefdescription visible="yes"/>
-    <directorygraph visible="yes"/>
-    <memberdecl>
-      <dirs visible="yes"/>
-      <files visible="yes"/>
-    </memberdecl>
-    <detaileddescription title=""/>
-  </directory>
-</doxygenlayout>

doc/Jamfile

@@ -1,80 +1,17 @@
-project redis/doc ;
+#
+# Copyright (c) 2025 Ruben Perez Hidalgo (rubenperez038 at gmail dot com)
+#
+# Distributed under the Boost Software License, Version 1.0. (See accompanying
+# file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+#
 
-import doxygen ;
-import path ;
-import sequence ;
+# Adapted from Boost.Unordered
+make html/index.html : build_antora.sh : @run-script ;
 
-# All paths must be absolute to work well with the Doxygen rules.
-path-constant this_dir : . ;
-path-constant target_dir : html ;
-path-constant redis_root_dir : .. ;
-path-constant include_dir : ../include ;
-path-constant examples_dir : ../example ;
-path-constant readme : ../README.md ;
-path-constant layout_file : DoxygenLayout.xml ;
-
-local stylesheet_files = [ path.glob $(this_dir) : *.css ] ;
-local includes = [ path.glob-tree $(include_dir) : *.hpp *.cpp ] ;
-local examples = [ path.glob-tree $(examples_dir) : *.hpp *.cpp ] ;
-
-# If passed directly, several HTML_EXTRA_STYLESHEET tags are generated,
-# which is not correct.
-local stylesheet_arg = [ sequence.join "\"$(stylesheet_files)\"" : " " ] ;
-
-# The doxygen rule requires the target name to end in .html to generate HTML files
-doxygen doc.html
-    :
-        $(includes) $(examples) $(readme)
-    :
-        <doxygen:param>"PROJECT_NAME=Boost.Redis"
-        <doxygen:param>PROJECT_NUMBER="1.4.2"
-        <doxygen:param>PROJECT_BRIEF="A redis client library"
-        <doxygen:param>"STRIP_FROM_PATH=\"$(redis_root_dir)\""
-        <doxygen:param>"STRIP_FROM_INC_PATH=\"$(include_dir)\""
-        <doxygen:param>BUILTIN_STL_SUPPORT=YES
-        <doxygen:param>INLINE_SIMPLE_STRUCTS=YES
-        <doxygen:param>HIDE_UNDOC_MEMBERS=YES
-        <doxygen:param>HIDE_UNDOC_CLASSES=YES
-        <doxygen:param>SHOW_HEADERFILE=YES
-        <doxygen:param>SORT_BRIEF_DOCS=YES
-        <doxygen:param>SORT_MEMBERS_CTORS_1ST=YES
-        <doxygen:param>SHOW_FILES=NO
-        <doxygen:param>SHOW_NAMESPACES=NO
-        <doxygen:param>"LAYOUT_FILE=\"$(layout_file)\""
-        <doxygen:param>WARN_IF_INCOMPLETE_DOC=YES
-        <doxygen:param>FILE_PATTERNS="*.hpp *.cpp"
-        <doxygen:param>EXCLUDE_SYMBOLS=std
-        <doxygen:param>"USE_MDFILE_AS_MAINPAGE=\"$(readme)\""
-        <doxygen:param>SOURCE_BROWSER=YES
-        <doxygen:param>"HTML_EXTRA_STYLESHEET=$(stylesheet_arg)"
-        <doxygen:param>HTML_TIMESTAMP=YES
-        <doxygen:param>GENERATE_TREEVIEW=YES
-        <doxygen:param>FULL_SIDEBAR=NO
-        <doxygen:param>ENUM_VALUES_PER_LINE=0
-        <doxygen:param>OBFUSCATE_EMAILS=YES
-        <doxygen:param>USE_MATHJAX=YES
-        <doxygen:param>MATHJAX_VERSION=MathJax_2
-        <doxygen:param>MATHJAX_RELPATH="https://cdnjs.cloudflare.com/ajax/libs/mathjax/2.7.5/"
-        <doxygen:param>MACRO_EXPANSION=YES
-        <doxygen:param>HAVE_DOT=NO
-        <doxygen:param>CLASS_GRAPH=NO
-        <doxygen:param>DIRECTORY_GRAPH=NO
-    ;
-
-explicit doc.html ;
-
-# The doxygen rule only informs b2 about the main HTML file, and not about
-# all the doc directory that gets generated. Using the install rule copies
-# only a single file, which is incorrect. This is a workaround to copy
-# the generated docs to the doc/html directory, where they should be.
-make copyhtml.tag : doc.html : @copy_html_dir ;
-explicit copyhtml.tag ;
-actions copy_html_dir
+# Runs the Antora script
+actions run-script
 {
-    rm -rf $(target_dir)
-    mkdir -p $(target_dir)
-    cp -r $(<:D)/html/doc/* $(target_dir)/
-    echo "Stamped" > "$(<)"
+    bash -x $(>)
 }
 
 # These are used to inform the build system of the
@@ -83,5 +20,5 @@ actions copy_html_dir
 alias boostdoc ;
 explicit boostdoc ;
 
-alias boostrelease : copyhtml.tag ;
+alias boostrelease : html/index.html ;
 explicit boostrelease ;

doc/antora.yml

@@ -0,0 +1,15 @@
+#
+# Copyright (c) 2025 Ruben Perez Hidalgo (rubenperez038 at gmail dot com)
+#
+# Distributed under the Boost Software License, Version 1.0. (See accompanying
+# file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+#
+
+name: redis
+title: Boost.Redis
+version: ~
+nav:
+  - modules/ROOT/nav.adoc
+ext:
+  cpp-reference:
+    config: doc/mrdocs.yml

doc/build_antora.sh

@@ -0,0 +1,19 @@
+#!/bin/bash
+#
+# Copyright (c) 2025 Ruben Perez Hidalgo (rubenperez038 at gmail dot com)
+#
+# Distributed under the Boost Software License, Version 1.0. (See accompanying
+# file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+#
+
+set -e
+
+SCRIPT_DIR=$( cd -- "$( dirname -- "${BASH_SOURCE[0]}" )" &> /dev/null && pwd )
+cd "$SCRIPT_DIR"
+
+# Required by our CMake.
+# Prevents Antora from cloning Boost again
+export BOOST_SRC_DIR=$(realpath $SCRIPT_DIR/../../..)
+
+npm ci
+npx antora --log-format=pretty --stacktrace --log-level info redis-playbook.yml

doc/doxygen-awesome-sidebar-only.css

@@ -1,115 +0,0 @@
-/**
-
-Doxygen Awesome
-https://github.com/jothepro/doxygen-awesome-css
-
-MIT License
-
-Copyright (c) 2021 jothepro
-
-Permission is hereby granted, free of charge, to any person obtaining a copy
-of this software and associated documentation files (the "Software"), to deal
-in the Software without restriction, including without limitation the rights
-to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
-copies of the Software, and to permit persons to whom the Software is
-furnished to do so, subject to the following conditions:
-
-The above copyright notice and this permission notice shall be included in all
-copies or substantial portions of the Software.
-
-THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
-IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
-FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
-AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
-LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
-OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
-SOFTWARE.
-
- */
-
-html {
-    /* side nav width. MUST be = `TREEVIEW_WIDTH`.
-     * Make sure it is wide enough to contain the page title (logo + title + version)
-     */
-    --side-nav-fixed-width: 335px;
-    --menu-display: none;
-
-    --top-height: 120px;
-    --toc-sticky-top: -25px;
-    --toc-max-height: calc(100vh - 2 * var(--spacing-medium) - 25px);
-}
-
-#projectname {
-    white-space: nowrap;
-}
-
-
-@media screen and (min-width: 768px) {
-    html {
-        --searchbar-background: var(--page-background-color);
-    }
-
-    #side-nav {
-        min-width: var(--side-nav-fixed-width);
-        max-width: var(--side-nav-fixed-width);
-        top: var(--top-height);
-        overflow: visible;
-    }
-
-    #nav-tree, #side-nav {
-        height: calc(100vh - var(--top-height)) !important;
-    }
-
-    #nav-tree {
-        padding: 0;
-    }
-
-    #top {
-        display: block;
-        border-bottom: none;
-        height: var(--top-height);
-        margin-bottom: calc(0px - var(--top-height));
-        max-width: var(--side-nav-fixed-width);
-        overflow: hidden;
-        background: var(--side-nav-background);
-    }
-    #main-nav {
-        float: left;
-        padding-right: 0;
-    }
-
-    .ui-resizable-handle {
-        cursor: default;
-        width: 1px !important;
-        box-shadow: 0 calc(-2 * var(--top-height)) 0 0 var(--separator-color);
-    }
-
-    #nav-path {
-        position: fixed;
-        right: 0;
-        left: var(--side-nav-fixed-width);
-        bottom: 0;
-        width: auto;
-    }
-
-    #doc-content {
-        height: calc(100vh - 31px) !important;
-        padding-bottom: calc(3 * var(--spacing-large));
-        padding-top: calc(var(--top-height) - 80px);
-        box-sizing: border-box;
-        margin-left: var(--side-nav-fixed-width) !important;
-    }
-
-    #MSearchBox {
-        width: calc(var(--side-nav-fixed-width) - calc(2 * var(--spacing-medium)));
-    }
-
-    #MSearchField {
-        width: calc(var(--side-nav-fixed-width) - calc(2 * var(--spacing-medium)) - 65px);
-    }
-
-    #MSearchResultsWindow {
-        left: var(--spacing-medium) !important;
-        right: auto;
-    }
-}

doc/modules/ROOT/nav.adoc

@@ -0,0 +1,12 @@
+* xref:index.adoc[Introduction]
+* xref:requests_responses.adoc[]
+* xref:cancellation.adoc[]
+* xref:serialization.adoc[]
+* xref:logging.adoc[]
+* xref:sentinel.adoc[]
+* xref:benchmarks.adoc[]
+* xref:comparison.adoc[]
+* xref:examples.adoc[]
+* xref:reference.adoc[Reference]
+* xref:acknowledgements.adoc[]
+* xref:changelog.adoc[]

doc/modules/ROOT/pages/acknowledgements.adoc

@@ -0,0 +1,37 @@
+//
+// Copyright (c) 2025 Marcelo Zimbres Silva (mzimbres@gmail.com)
+//
+// Distributed under the Boost Software License, Version 1.0. (See accompanying
+// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+//
+
+= Acknowledgements
+
+Acknowledgement to people that helped shape Boost.Redis
+
+* Richard Hodges (https://github.com/madmongo1[madmongo1]): For very helpful support with Asio, the design of asynchronous programs, etc.
+* Vinícius dos Santos Oliveira (https://github.com/vinipsmaker[vinipsmaker]): For useful discussion about how Boost.Redis consumes buffers in the read operation.
+* Petr Dannhofer (https://github.com/Eddie-cz[Eddie-cz]): For helping me understand how the `AUTH` and `HELLO` command can influence each other.
+* Mohammad Nejati (https://github.com/ashtum[ashtum]): For pointing out scenarios where calls to `async_exec` should fail when the connection is lost.
+* Klemens Morgenstern (https://github.com/klemens-morgenstern[klemens-morgenstern]): For useful discussion about timeouts, cancellation, synchronous interfaces and general help with Asio.
+* Vinnie Falco (https://github.com/vinniefalco[vinniefalco]): For general suggestions about how to improve the code and the documentation.
+* Bram Veldhoen (https://github.com/bveldhoen[bveldhoen]): For contributing a Redis-streams example.
+
+Also many thanks to all individuals that participated in the Boost
+review
+
+* Zach Laine: https://lists.boost.org/Archives/boost/2023/01/253883.php
+* Vinnie Falco: https://lists.boost.org/Archives/boost/2023/01/253886.php
+* Christian Mazakas: https://lists.boost.org/Archives/boost/2023/01/253900.php
+* Ruben Perez: https://lists.boost.org/Archives/boost/2023/01/253915.php
+* Dmitry Arkhipov: https://lists.boost.org/Archives/boost/2023/01/253925.php
+* Alan de Freitas: https://lists.boost.org/Archives/boost/2023/01/253927.php
+* Mohammad Nejati: https://lists.boost.org/Archives/boost/2023/01/253929.php
+* Sam Hartsfield: https://lists.boost.org/Archives/boost/2023/01/253931.php
+* Miguel Portilla: https://lists.boost.org/Archives/boost/2023/01/253935.php
+* Robert A.H. Leahy: https://lists.boost.org/Archives/boost/2023/01/253928.php
+
+The Reviews can be found at:
+https://lists.boost.org/Archives/boost/2023/01/date.php. The thread
+with the ACCEPT from the review manager can be found here:
+https://lists.boost.org/Archives/boost/2023/01/253944.php.

doc/modules/ROOT/pages/benchmarks.adoc

@@ -0,0 +1,95 @@
+//
+// Copyright (c) 2025 Marcelo Zimbres Silva (mzimbres@gmail.com)
+//
+// Distributed under the Boost Software License, Version 1.0. (See accompanying
+// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+//
+
+= Echo server benchmark
+
+This document benchmarks the performance of TCP echo servers I
+implemented in different languages using different Redis clients.  The
+main motivations for choosing an echo server are
+
+   * Simple to implement and does not require expertise level in most languages.
+   * I/O bound: Echo servers have very low CPU consumption in general
+     and  therefore are excellent to  measure how a program handles concurrent requests.
+   * It simulates very well a typical backend in regard to concurrency.
+
+I also imposed some constraints on the implementations
+
+   * It should be simple enough and not require writing too much code.
+   * Favor the use standard idioms and avoid optimizations that require expert level.
+   * Avoid the use of complex things like connection and thread pool.
+
+To reproduce these results run one of the echo-server programs in one
+terminal and the
+https://github.com/boostorg/redis/blob/42880e788bec6020dd018194075a211ad9f339e8/benchmarks/cpp/asio/echo_server_client.cpp[echo-server-client] in another.
+
+== Without Redis
+
+First I tested a pure TCP echo server, i.e. one that sends the messages
+directly to the client without interacting with Redis. The result can
+be seen below
+
+image::https://boostorg.github.io/redis/tcp-echo-direct.png[]
+
+The tests were performed with a 1000 concurrent TCP connections on the
+localhost where latency is 0.07ms on average on my machine. On higher
+latency networks the difference among libraries is expected to
+decrease. 
+
+   * I expected Libuv to have similar performance to Asio and Tokio.
+   * I did expect nodejs to come a little behind given it is is
+     javascript code. Otherwise I did expect it to have similar
+     performance to libuv since it is the framework behind it.
+   * Go did surprise me: faster than nodejs and libuv!
+
+The code used in the benchmarks can be found at
+
+   * https://github.com/boostorg/redis/blob/3fb018ccc6138d310ac8b73540391cdd8f2fdad6/benchmarks/cpp/asio/echo_server_direct.cpp[Asio]: A variation of https://github.com/chriskohlhoff/asio/blob/4915cfd8a1653c157a1480162ae5601318553eb8/asio/src/examples/cpp20/coroutines/echo_server.cpp[this Asio example].
+   * https://github.com/boostorg/redis/tree/835a1decf477b09317f391eddd0727213cdbe12b/benchmarks/c/libuv[Libuv]: Taken from https://github.com/libuv/libuv/blob/06948c6ee502862524f233af4e2c3e4ca876f5f6/docs/code/tcp-echo-server/main.c[this Libuv example].
+   * https://github.com/boostorg/redis/tree/3fb018ccc6138d310ac8b73540391cdd8f2fdad6/benchmarks/rust/echo_server_direct[Tokio]: Taken from https://docs.rs/tokio/latest/tokio/[here].
+   * https://github.com/boostorg/redis/tree/3fb018ccc6138d310ac8b73540391cdd8f2fdad6/benchmarks/nodejs/echo_server_direct[Nodejs]
+   * https://github.com/boostorg/redis/blob/3fb018ccc6138d310ac8b73540391cdd8f2fdad6/benchmarks/go/echo_server_direct.go[Go]
+
+== With Redis
+
+This is similar to the echo server described above but messages are
+echoed by Redis and not by the echo-server itself, which acts
+as a proxy between the client and the Redis server. The results
+can be seen below
+
+image::https://boostorg.github.io/redis/tcp-echo-over-redis.png[]
+
+The tests were performed on a network where latency is 35ms on
+average, otherwise it uses the same number of TCP connections
+as the previous example.
+
+As the reader can see, the Libuv and the Rust test are not depicted
+in the graph, the reasons are
+
+   * https://github.com/redis-rs/redis-rs[redis-rs]: This client
+     comes so far behind that it can't even be represented together
+     with the other benchmarks without making them look insignificant.
+     I don't know for sure why it is so slow, I suppose it has
+     something to do with its lack of automatic
+     https://redis.io/docs/manual/pipelining/[pipelining] support.
+     In fact, the more TCP connections I launch the worse its
+     performance gets.
+
+   * Libuv: I left it out because it would require me writing to much
+     c code. More specifically, I would have to use hiredis and
+     implement support for pipelines manually.
+
+The code used in the benchmarks can be found at
+
+   * https://github.com/boostorg/redis[Boost.Redis]: https://github.com/boostorg/redis/blob/3fb018ccc6138d310ac8b73540391cdd8f2fdad6/examples/echo_server.cpp[code]
+   * https://github.com/redis/node-redis[node-redis]: https://github.com/boostorg/redis/tree/3fb018ccc6138d310ac8b73540391cdd8f2fdad6/benchmarks/nodejs/echo_server_over_redis[code]
+   * https://github.com/go-redis/redis[go-redis]: https://github.com/boostorg/redis/blob/3fb018ccc6138d310ac8b73540391cdd8f2fdad6/benchmarks/go/echo_server_over_redis.go[code]
+
+
+== Conclusion
+
+Redis clients have to support automatic pipelining to have competitive performance. For updates to this document follow https://github.com/boostorg/redis[].
+

doc/modules/ROOT/pages/cancellation.adoc

@@ -0,0 +1,79 @@
+//
+// Copyright (c) 2025 Marcelo Zimbres Silva (mzimbres@gmail.com),
+// Ruben Perez Hidalgo (rubenperez038 at gmail dot com)
+//
+// Distributed under the Boost Software License, Version 1.0. (See accompanying
+// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+//
+
+= Cancellation and timeouts
+
+By default, running a request with xref:reference:boost/redis/basic_connection/async_exec-02.adoc[`async_exec`]
+will wait until a connection to the Redis server is established by `async_run`.
+This may take a very long time if the server is down.
+
+For this reason, it is usually a good idea to set a timeout to `async_exec`
+operations using the
+https://www.boost.org/doc/libs/latest/doc/html/boost_asio/reference/cancel_after.html[`asio::cancel_after`]
+completion token:
+
+
+[source,cpp]
+----
+using namespace std::chrono_literals;
+
+// Compose a request with a SET command
+request req;
+req.push("SET", "my_key", 42);
+
+// If the request hasn't completed after 10 seconds, it will be cancelled
+// and an exception will be thrown.
+co_await conn.async_exec(req, ignore, asio::cancel_after(10s));
+----
+
+See our {site-url}/example/cpp20_timeouts.cpp[example on timeouts]
+for a full code listing.
+
+You can also use `cancel_after` with other completion styles, like
+callbacks and futures.
+
+`cancel_after` works because `async_exec` supports the per-operation
+cancellation mechanism. This is used by Boost.Asio to implement features
+like `cancel_after` and parallel groups. All asynchronous operations
+in the library support this mechanism. Please consult the documentation
+for individual operations for more info.
+
+
+== Retrying idempotent requests
+
+We mentioned that `async_exec` waits until the server is up
+before sending the request. But what happens if there is a communication
+error after sending the request, but before receiving a response?
+
+In this situation there is no way to know if the request was processed by the server or not.
+By default, the library will consider the request as failed,
+and `async_exec` will complete with an `asio::error::operation_aborted`
+error code.
+
+Some requests can be executed several times and result in the same outcome
+as executing them only once. We say that these requests are _idempotent_.
+The `SET` command is idempotent, while `INCR` is not.
+
+If you know that a `request` object contains only idempotent commands,
+you can instruct Boost.Redis to retry the request on failure, even
+if the library is unsure about the server having processed the request or not.
+You can do so by setting `cancel_if_unresponded`
+in xref:reference:boost/redis/request/config.adoc[`request::config`]
+to false:
+
+[source,cpp]
+----
+// Compose a request
+request req;
+req.push("SET", "my_key", 42); // idempotent
+req.get_config().cancel_if_unresponded = false; // Retry the request even if it was written but not responded
+
+// Makes sure that the key is set, even in the presence of network errors.
+// This may suspend for an unspecified period of time if the server is down.
+co_await conn.async_exec(req, ignore);
+----

doc/modules/ROOT/pages/changelog.adoc

@@ -0,0 +1,537 @@
+//
+// Copyright (c) 2025 Marcelo Zimbres Silva (mzimbres@gmail.com)
+//
+// Distributed under the Boost Software License, Version 1.0. (See accompanying
+// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+//
+
+= Changelog
+
+== Boost 1.90
+
+
+* (Pull request https://github.com/boostorg/redis/pull/310[310])
+  Improves the per-operation support in `async_exec()`. Requests can now
+  be cancelled at any point, and cancellations don't interfere with other
+  requests anyhow. In previous versions, a cancellation could cause
+  `async_run()` to be cancelled, making cancellations unpredictable.
+* (Issue https://github.com/boostorg/redis/issues/226[226])
+  Added support for the `asio::cancel_after` and `asio::cancel_at`
+  completion tokens in `async_exec()` and `async_run()`.
+* (Issue https://github.com/boostorg/redis/issues/319[319])
+  Added support for per-operation cancellation in `async_run()`.
+* (Pull request https://github.com/boostorg/redis/pull/329[329]
+  and https://github.com/boostorg/redis/pull/334[334])
+  The `cancel_on_connection_lost` and `cancel_if_not_connected`
+  flags in `request::config` have been deprecated, and will be removed
+  in subsequent releases. To limit the time span that `async_exec`
+  might take, use `asio::cancel_after`, instead.
+  `cancel_on_connection_lost` default has been changed to `false`.
+  This shouldn't cause much impact, since `cancel_on_connection_lost`
+  is not a reliable way to limit the time span that `async_exec` might take.
+* (Pull request https://github.com/boostorg/redis/pull/321[321])
+  Calling `cancel` with `operation::resolve`, `operation::connect`,
+  `operation::ssl_handshake`, `operation::reconnection` and
+  `operation::health_check` is now deprecated.
+  These enumerators will be removed in subsequent releases.
+  Users should employ `cancel(operation::run)`, instead.
+* (Issue github.com/boostorg/redis/issues/302[302] and
+  pull request https://github.com/boostorg/redis/pull/303[303])
+  Added support for custom setup requests using `config::setup`
+  and `config::use_setup`. When setting these fields, users can
+  replace the library-generated `HELLO` request by any other arbitrary request.
+  This request is executed every time a new physical connection with the server
+  is established. This feature can be used to interact with systems that don't
+  support `HELLO`, to handle authentication and to connect to replicas.
+* (Pull request https://github.com/boostorg/redis/pull/305[305])
+  `request::config::hello_with_priority` and `request::has_hello_priority()` have
+  been deprecated and will be removed in subsequent releases.
+  This flag is not well specified and should only be used by the library.
+  If you need to execute a request before any other, use `config::setup`, instead.
+* (Issue https://github.com/boostorg/redis/issues/296[296])
+  Valkey long-term support: we guarantee Valkey compatibility
+  starting with this release. Previous releases may also work,
+  but have not been tested with this database system.
+* (Issue https://github.com/boostorg/redis/issues/341[341])
+  Adds a `request::append()` function, to concatenate request objects.
+* (Issue https://github.com/boostorg/redis/issues/104[104])
+  The health checker algorithm has been redesigned to avoid
+  false positives under heavy loads. `PING` commands are now
+  only issued when the connection is idle, instead of periodically.
+* (Pull request https://github.com/boostorg/redis/pull/283[283])
+  Added `config::read_buffer_append_size`, which allows to control
+  the expansion of the connection's read buffer.
+* (Pull request https://github.com/boostorg/redis/pull/311[311])
+  Added `usage::bytes_rotated`, which measures data copying when
+  reading and parsing data from the server.
+* (Issue https://github.com/boostorg/redis/issues/298[298])
+  Added support for authenticating users with an empty password
+  but a non-default username.
+* (Issue https://github.com/boostorg/redis/issues/318[318])
+  Fixed a number of race conditions in the `cancel()` function
+  of `connection` and `basic_connection` that could cause
+  cancellations to be ignored.
+* (Issue https://github.com/boostorg/redis/issues/290[290])
+  Fixed a problem that could cause an error during `HELLO`
+  to make subsequent `HELLO` attempts during reconnection to fail.
+* (Issue https://github.com/boostorg/redis/issues/297[297])
+  Errors during `HELLO` are now correctly logged.
+* (Issue https://github.com/boostorg/redis/issues/287[287])
+  Fixed a bug causing an exception to be thrown when parsing
+  a response that contains an intermediate error into a `generic_response`.
+
+
+== Boost 1.89
+
+* (Pull request https://github.com/boostorg/redis/pull/256[256],
+   https://github.com/boostorg/redis/pull/266[266] and
+   https://github.com/boostorg/redis/pull/273[273])
+  The following members in `connection` and `basic_connection` are now deprecated
+  and will be removed in subsequent releases:
+  * `next_layer()` and `next_layer_type`: there is no reason to access the underlying stream object directly.
+    Connection member functions should be used, instead.
+  * `get_ssl_context()`: SSL contexts should never be modified after an `asio::ssl::stream`
+    object has been created from them. Properties should be set before passing the context
+    to the constructor. There is no reason to access the SSL context after that.
+  * `reset_stream()`: connection internals have been refactored to reset the SSL stream
+    automatically when required. This function is now a no-op.
+  * The `async_run()` overload taking no parameters: use the `async_run`
+    overload taking a `config` object explicitly, instead.
+* (Issue https://github.com/boostorg/redis/issues/213[213])
+  The logging interface has been re-written:
+  * Logging can now be customized by passing a function object
+    to the `logger` constructor. This allows integration with
+    third-party logging libraries, like spdlog.
+    This new logging interface is public and will be maintained long-term.
+  * The old, unstable interface consisting of `logger::on_xxx` functions has been removed.
+  * `connection` and `basic_connection` constructors now accept a `logger` object.
+    This is now the preferred way to configure logging.
+    The `async_run()` overload taking a `logger` object is now deprecated, and will
+    be removed in subsequent releases.
+  * `config::log_prefix` is now deprecated, and will
+    be removed in subsequent releases. Users can achieve the same effect
+    by passing a custom logging function to the `logger` constructor.
+  * The default logging function, which prints to `stderr`,
+    is now based on `printf` and is thus thread-safe.
+    The old function used `std::cerr` and could result to interleaved
+    output in multi-threaded programs.
+  * The default log level is now `logger::level::info`,
+    down from `logger::level::debug`. This results in less verbose output by default.
+* (Issue https://github.com/boostorg/redis/issues/272[272])
+  Added support for connecting to Redis using UNIX domain sockets.
+  This feature can be accessed using `config::unix_socket`.
+* (Issue https://github.com/boostorg/redis/issues/255[255])
+  Fixed an issue that caused `async_run` to complete when a connection
+  establishment error is encountered, even if `config::reconnect_wait_interval`
+  specified reconnection.
+* (Issue https://github.com/boostorg/redis/issues/265[265])
+  `connection::async_exec` now uses `ignore` as the default response,
+  rather than having no default response. This matches
+  `basic_connection::async_exec` behavior.
+* (Issue https://github.com/boostorg/redis/issues/260[260])
+  Fixed a memory corruption affecting the logger's prefix
+  configured in `config::log_prefix`.
+* (Pull request https://github.com/boostorg/redis/pull/254[254])
+  Fixed some warnings regarding unused variables, name shadowing
+  and narrowing conversions.
+* (Issue https://github.com/boostorg/redis/issues/252[252])
+  Fixed a bug that causes reconnection to ignore the reconnection
+  wait time configured in `config::reconnect_wait_interval`.
+* (Issue https://github.com/boostorg/redis/issues/238[238])
+  Fixed a bug introduced in Boost 1.88 that caused `response<T>` to
+  not compile for some integral types.
+* (Issue https://github.com/boostorg/redis/issues/247[247])
+  The documentation has been modernized, and a more complete
+  reference section has been added.
+* Part of the internals have been refactored to allow for better
+  testing and reduce compile times.
+
+
+== Boost 1.88
+
+* (Issue https://github.com/boostorg/redis/issues/233[233])
+  To deal with keys that might not exits in the Redis server, the
+  library supports `std::optional`, for example
+  `response<std::optional<std::vector<std::string>>>`. In some cases
+  however, such as the https://redis.io/docs/latest/commands/mget/[MGET] command,
+  each element in the vector might be non exiting, now it is possible
+  to specify a response as `response<std::optional<std::vector<std::optional<std::string>>>>`.
+
+* (Issue https://github.com/boostorg/redis/issues/225[225])
+  Use `deferred` as the connection default completion token.
+
+* (Issue https://github.com/boostorg/redis/issues/128[128])
+  Adds a new `async_exec` overload that allows passing response
+  adapters. This makes it possible to receive Redis responses directly
+  in custom data structures thereby avoiding unnecessary data copying.
+  Thanks to Ruben Perez (@anarthal) for implementing this feature.
+
+* There are also other multiple small improvements in this release,
+  users can refer to the git history for more details.
+
+== Boost 1.87
+
+* (Issue https://github.com/boostorg/redis/issues/205[205])
+  Improves reaction time to disconnection by using `wait_for_one_error`
+  instead of `wait_for_all`. The function `connection::async_run` was
+  also changed to return EOF to the user when that error is received
+  from the server. That is a breaking change.
+
+* (Issue https://github.com/boostorg/redis/issues/210[210])
+  Fixes the adapter of empty nested responses.
+
+* (Issues https://github.com/boostorg/redis/issues/211[211] and https://github.com/boostorg/redis/issues/212[212])
+  Fixes the reconnect loop that would hang under certain conditions,
+  see the linked issues for more details.
+
+* (Issue https://github.com/boostorg/redis/issues/219[219])
+  Changes the default log level from `disabled` to `debug`.
+
+== Boost 1.85
+
+* (Issue https://github.com/boostorg/redis/issues/170[170])
+  Under load and on low-latency networks it is possible to start
+  receiving responses before the write operation completed and while
+  the request is still marked as staged and not written. This messes
+  up with the heuristics that classifies responses as unsolicited or
+  not.
+
+* (Issue https://github.com/boostorg/redis/issues/168[168]).
+  Provides a way of passing a custom SSL context to the connection.
+  The design here differs from that of Boost.Beast and Boost.MySql
+  since in Boost.Redis the connection owns the context instead of only
+  storing a reference to a user provided one. This is ok so because
+  apps need only one connection for their entire application, which
+  makes the overhead of one ssl-context per connection negligible.
+
+* (Issue https://github.com/boostorg/redis/issues/181[181]).
+  See a detailed description of this bug in
+  https://github.com/boostorg/redis/issues/181#issuecomment-1913346983[this comment].
+
+* (Issue https://github.com/boostorg/redis/issues/182[182]).
+  Sets `"default"` as the default value of `config::username`. This
+  makes it simpler to use the `requirepass` configuration in Redis.
+
+* (Issue https://github.com/boostorg/redis/issues/189[189]).
+  Fixes narrowing conversion by using `std::size_t` instead of
+  `std::uint64_t` for the sizes of bulks and aggregates. The code
+  relies now on `std::from_chars` returning an error if a value
+  greater than 32 is received on platforms on which the size
+  of `std::size_t` is 32.
+
+
+== Boost 1.84 (First release in Boost)
+
+* Deprecates the `async_receive` overload that takes a response. Users
+  should now first call `set_receive_response` to avoid constantly and
+  unnecessarily setting the same response.
+
+* Uses `std::function` to type erase the response adapter. This change
+  should not influence users in any way but allowed important
+  simplification in the connections internals. This resulted in
+  massive performance improvement.
+
+* The connection has a new member `get_usage()` that returns the
+  connection usage information, such as number of bytes written,
+  received etc.
+
+* There are massive performance improvements in the consuming of
+  server pushes which are now communicated with an `asio::channel` and
+  therefore can be buffered which avoids blocking the socket read-loop.
+  Batch reads are also supported by means of `channel.try_send` and
+  buffered messages can be consumed synchronously with
+  `connection::receive`. The function `boost::redis::cancel_one` has
+  been added to simplify processing multiple server pushes contained
+  in the same `generic_response`.  *IMPORTANT*: These changes may
+  result in more than one push in the response when
+  `connection::async_receive` resumes. The user must therefore be
+  careful when calling `resp.clear()`: either ensure that all message
+  have been processed or just use `consume_one`.
+
+== v1.4.2 (incorporates changes to conform the boost review and more)
+
+* Adds `boost::redis::config::database_index` to make it possible to
+  choose a database before starting running commands e.g. after an
+  automatic reconnection.
+
+* Massive performance improvement. One of my tests went from
+  140k req/s to 390k/s. This was possible after a parser
+  simplification that reduced the number of reschedules and buffer
+  rotations.
+
+* Adds Redis stream example.
+
+* Renames the project to Boost.Redis and moves the code into namespace
+  `boost::redis`.
+
+* As pointed out in the reviews the `to_bulk` and `from_bulk` names were too
+  generic for ADL customization points. They gained the prefix `boost_redis_`.
+
+* Moves `boost::redis::resp3::request` to `boost::redis::request`.
+
+* Adds new typedef `boost::redis::response` that should be used instead of
+  `std::tuple`.
+
+* Adds new typedef `boost::redis::generic_response` that should be used instead
+  of `std::vector<resp3::node<std::string>>`.
+
+* Renames `redis::ignore` to `redis::ignore_t`.
+
+* Changes `async_exec` to receive a `redis::response` instead of an adapter,
+  namely, instead of passing `adapt(resp)` users should pass `resp` directly.
+
+* Introduces `boost::redis::adapter::result` to store responses to commands
+  including possible resp3 errors without losing the error diagnostic part. To
+  access values now use `std::get<N>(resp).value()` instead of
+  `std::get<N>(resp)`.
+
+* Implements full-duplex communication. Before these changes the connection
+  would wait for a response to arrive before sending the next one. Now requests
+  are continuously coalesced and written to the socket. `request::coalesce`
+  became unnecessary and was removed. I could measure significative performance
+  gains with these changes.
+
+* Improves serialization examples using Boost.Describe to serialize to JSON and protobuf. See
+  cpp20_json.cpp and cpp20_protobuf.cpp for more details.
+
+* Upgrades to Boost 1.81.0.
+
+* Fixes build with pass:[libc++].
+
+* Adds high-level functionality to the connection classes. For
+  example, `boost::redis::connection::async_run` will automatically
+  resolve, connect, reconnect and perform health checks.
+
+== v1.4.0-1
+
+* Renames `retry_on_connection_lost` to `cancel_if_unresponded`.  (v1.4.1)
+* Removes dependency on Boost.Hana, `boost::string_view`, Boost.Variant2 and Boost.Spirit.
+* Fixes build and setup CI on windows.
+
+== v1.3.0-1
+
+* Upgrades to Boost 1.80.0
+
+* Removes automatic sending of the `HELLO` command. This can't be
+  implemented properly without bloating the connection class. It is
+  now a user responsibility to send HELLO. Requests that contain it have
+  priority over other requests and will be moved to the front of the
+  queue, see `aedis::request::config` 
+
+* Automatic name resolving and connecting have been removed from
+  `aedis::connection::async_run`. Users have to do this step manually
+  now. The reason for this change is that having them built-in doesn't
+  offer enough flexibility that is need for boost users.
+
+* Removes healthy checks and idle timeout. This functionality must now
+  be implemented by users, see the examples. This is
+  part of making Aedis useful to a larger audience and suitable for
+  the Boost review process.
+
+* The `aedis::connection` is now using a typeddef to a
+  `net::ip::tcp::socket` and  `aedis::ssl::connection` to
+  `net::ssl::stream<net::ip::tcp::socket>`.  Users that need to use
+  other stream type must now specialize `aedis::basic_connection`.
+
+* Adds a low level example of async code.
+
+== v1.2.0
+
+* `aedis::adapt` supports now tuples created with `std::tie`.
+  `aedis::ignore` is now an alias to the type of `std::ignore`.
+
+* Provides allocator support for the internal queue used in the
+  `aedis::connection` class.
+
+* Changes the behaviour of `async_run` to complete with success if
+  asio::error::eof is received. This makes it easier to  write
+  composed operations with awaitable operators.
+
+* Adds allocator support in the `aedis::request` (a
+  contribution from Klemens Morgenstern).
+
+* Renames `aedis::request::push_range2` to `push_range`. The
+  suffix 2 was used for disambiguation. Klemens fixed it with SFINAE.
+
+* Renames `fail_on_connection_lost` to
+  `aedis::request::config::cancel_on_connection_lost`. Now, it will
+  only cause connections to be canceled when `async_run` completes.
+
+* Introduces `aedis::request::config::cancel_if_not_connected` which will
+  cause a request to be canceled if `async_exec` is called before a
+  connection has been established.
+
+* Introduces new request flag `aedis::request::config::retry` that if
+  set to true will cause the request to not be canceled when it was
+  sent to Redis but remained unresponded after `async_run` completed.
+  It provides a way to avoid executing commands twice.
+
+* Removes the `aedis::connection::async_run` overload that takes
+  request and adapter as parameters.
+
+* Changes the way `aedis::adapt()` behaves with
+  `std::vector<aedis::resp3::node<T>>`. Receiving RESP3 simple errors,
+  blob errors or null won't causes an error but will be treated as
+  normal response.  It is the user responsibility to check the content
+  in the vector.
+
+* Fixes a bug in `connection::cancel(operation::exec)`. Now this
+  call will only cancel non-written requests.
+
+* Implements per-operation implicit cancellation support for
+  `aedis::connection::async_exec`. The following call will `co_await (conn.async_exec(...) || timer.async_wait(...))`
+  will cancel the request as long as it has not been written.
+
+* Changes `aedis::connection::async_run` completion signature to
+  `f(error_code)`. This is how is was in the past, the second
+  parameter was not helpful.
+
+* Renames `operation::receive_push` to `aedis::operation::receive`.
+
+== v1.1.0-1
+
+* Removes `coalesce_requests` from the `aedis::connection::config`, it
+  became a request property now, see `aedis::request::config::coalesce`.
+
+* Removes `max_read_size` from the `aedis::connection::config`. The maximum
+  read size can be specified now as a parameter of the
+  `aedis::adapt()` function.
+
+* Removes `aedis::sync` class, see intro_sync.cpp for how to perform
+  synchronous and thread safe calls. This is possible in Boost. 1.80
+  only as it requires `boost::asio::deferred`. 
+
+* Moves from `boost::optional` to `std::optional`. This is part of
+  moving to pass:[C++17].
+
+* Changes the behaviour of the second `aedis::connection::async_run` overload
+  so that it always returns an error when the connection is lost.
+
+* Adds TLS support, see intro_tls.cpp.
+
+* Adds an example that shows how to resolve addresses over sentinels,
+  see subscriber_sentinel.cpp.
+
+* Adds a `aedis::connection::timeouts::resp3_handshake_timeout`. This is
+  timeout used to send the `HELLO` command.
+
+* Adds `aedis::endpoint` where in addition to host and port, users can
+  optionally provide username, password and the expected server role
+  (see `aedis::error::unexpected_server_role`).
+
+* `aedis::connection::async_run` checks whether the server role received in
+  the hello command is equal to the expected server role specified in
+  `aedis::endpoint`. To skip this check let the role variable empty.
+
+* Removes reconnect functionality from `aedis::connection`. It
+  is possible in simple reconnection strategies but bloats the class
+  in more complex scenarios, for example, with sentinel,
+  authentication and TLS. This is trivial to implement in a separate
+  coroutine. As a result the `enum event` and `async_receive_event`
+  have been removed from the class too.
+
+* Fixes a bug in `connection::async_receive_push` that prevented
+  passing any response adapter other that `adapt(std::vector<node>)`.
+
+* Changes the behaviour of `aedis::adapt()` that caused RESP3 errors
+  to be ignored. One consequence of it is that `connection::async_run`
+  would not exit with failure in servers that required authentication.
+
+* Changes the behaviour of `connection::async_run` that would cause it
+  to complete with success when an error in the
+  `connection::async_exec` occurred.
+
+* Ports the buildsystem from autotools to CMake.
+
+== v1.0.0
+
+* Adds experimental cmake support for windows users.
+
+* Adds new class `aedis::sync` that wraps an `aedis::connection` in
+  a thread-safe and synchronous API.  All free functions from the
+  `sync.hpp` are now member functions of `aedis::sync`.
+
+* Split `aedis::connection::async_receive_event` in two functions, one
+  to receive events and another for server side pushes, see
+  `aedis::connection::async_receive_push`.
+
+* Removes collision between `aedis::adapter::adapt` and
+  `aedis::adapt`.
+
+* Adds `connection::operation` enum to replace `cancel_*` member
+  functions with a single cancel function that gets the operations
+  that should be cancelled as argument.
+
+* Bugfix: a bug on reconnect from a state where the `connection` object
+  had unsent commands. It could cause `async_exec` to never
+  complete under certain conditions.
+
+* Bugfix: Documentation of `adapt()` functions were missing from
+  Doxygen.
+
+== v0.3.0
+
+* Adds `experimental::exec` and `receive_event` functions to offer a
+  thread safe and synchronous way of executing requests across
+  threads. See `intro_sync.cpp` and `subscriber_sync.cpp` for
+  examples.
+
+* `connection::async_read_push` was renamed to `async_receive_event`.
+
+* `connection::async_receive_event` is now being used to communicate
+  internal events to the user, such as resolve, connect, push etc. For
+  examples see cpp20_subscriber.cpp and `connection::event`.
+
+* The `aedis` directory has been moved to `include` to look more
+  similar to Boost libraries. Users should now replace `-I/aedis-path`
+  with `-I/aedis-path/include` in the compiler flags.
+
+* The `AUTH` and `HELLO` commands are now sent automatically. This change was
+  necessary to implement reconnection. The username and password
+  used in `AUTH` should be provided by the user on
+  `connection::config`.
+
+* Adds support for reconnection. See `connection::enable_reconnect`.
+
+* Fixes a bug in the `connection::async_run(host, port)` overload
+  that was causing crashes on reconnection.
+
+* Fixes the executor usage in the connection class. Before these
+  changes it was imposing `any_io_executor` on users.
+
+* `connection::async_receiver_event` is not cancelled anymore when
+  `connection::async_run` exits. This change makes user code simpler.
+
+* `connection::async_exec` with host and port overload has been
+  removed. Use the other `connection::async_run` overload.
+
+* The host and port parameters from `connection::async_run` have been
+  move to `connection::config` to better support authentication and
+  failover.
+
+* Many simplifications in the `chat_room` example.
+
+* Fixes build in clang the compilers and makes some improvements in
+  the documentation.
+
+== v0.2.0-1
+
+* Fixes a bug that happens on very high load. (v0.2.1) 
+* Major rewrite of the high-level API. There is no more need to use the low-level API anymore.
+* No more callbacks: Sending requests follows the ASIO asynchronous model.
+* Support for reconnection: Pending requests are not canceled when a connection is lost and are re-sent when a new one is established.
+* The library is not sending HELLO-3 on user behalf anymore. This is important to support AUTH properly.
+
+== v0.1.0-2
+
+* Adds reconnect coroutine in the `echo_server` example. (v0.1.2)
+* Corrects `client::async_wait_for_data` with `make_parallel_group` to launch operation. (v0.1.2)
+* Improvements in the documentation. (v0.1.2)
+* Avoids dynamic memory allocation in the client class after reconnection. (v0.1.2)
+* Improves the documentation and adds some features to the high-level client. (v.0.1.1)
+* Improvements in the design and documentation.
+
+== v0.0.1
+
+* First release to collect design feedback.
+

doc/modules/ROOT/pages/comparison.adoc

@@ -0,0 +1,121 @@
+//
+// Copyright (c) 2025 Marcelo Zimbres Silva (mzimbres@gmail.com)
+//
+// Distributed under the Boost Software License, Version 1.0. (See accompanying
+// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+//
+
+= Comparison with other Redis clients
+
+## Comparison
+
+The main reason for why I started writing Boost.Redis was to have a client
+compatible with the Asio asynchronous model. As I made progresses I could
+also address what I considered weaknesses in other libraries.  Due to
+time constraints I won't be able to give a detailed comparison with
+each client listed in the
+https://redis.io/docs/clients/#cpp[official list].
+Instead, I will focus on the most popular pass:[C++] client on github in number of stars, namely:
+
+https://github.com/sewenew/redis-plus-plus[]
+
+### Boost.Redis vs Redis-plus-plus
+
+Before we start it is important to mention some of the things
+redis-plus-plus does not support
+
+* The latest version of the communication protocol RESP3. Without that it is impossible to support some important Redis features like client side caching, among other things.
+* Coroutines.
+* Reading responses directly in user data structures to avoid creating temporaries.
+* Error handling with support for error-code.
+* Cancellation.
+
+The remaining points will be addressed individually.  Let us first
+have a look at what sending a command a pipeline and a transaction
+look like
+
+[source,cpp]
+----
+auto redis = Redis("tcp://127.0.0.1:6379");
+
+// Send commands
+redis.set("key", "val");
+auto val = redis.get("key"); // val is of type OptionalString.
+if (val)
+    std::cout << *val << std::endl;
+
+// Sending pipelines
+auto pipe = redis.pipeline();
+auto pipe_replies = pipe.set("key", "value")
+                        .get("key")
+                        .rename("key", "new-key")
+                        .rpush("list", {"a", "b", "c"})
+                        .lrange("list", 0, -1)
+                        .exec();
+
+// Parse reply with reply type and index.
+auto set_cmd_result = pipe_replies.get<bool>(0);
+// ...
+
+// Sending a transaction
+auto tx = redis.transaction();
+auto tx_replies = tx.incr("num0")
+                    .incr("num1")
+                    .mget({"num0", "num1"})
+                    .exec();
+
+auto incr_result0 = tx_replies.get<long long>(0);
+// ...
+----
+
+Some of the problems with this API are
+
+* Heterogeneous treatment of commands, pipelines and transaction. This makes auto-pipelining impossible.
+* Any Api that sends individual commands has a very restricted scope of usability and should be avoided for performance reasons.
+* The API imposes exceptions on users, no error-code overload is provided.
+* No way to reuse the buffer for new calls to e.g. redis.get in order to avoid further dynamic memory allocations.
+* Error handling of resolve and connection not clear.
+
+According to the documentation, pipelines in redis-plus-plus have
+the following characteristics
+
+> +NOTE+: By default, creating a Pipeline object is NOT cheap, since
+> it creates a new connection.
+
+This is clearly a downside in the API as pipelines should be the
+default way of communicating and not an exception, paying such a
+high price for each pipeline imposes a severe cost in performance.
+Transactions also suffer from the very same problem:
+
+> +NOTE+: Creating a Transaction object is NOT cheap, since it
+> creates a new connection.
+
+In Boost.Redis there is no difference between sending one command, a
+pipeline or a transaction because requests are decoupled
+from the I/O objects.
+
+> redis-plus-plus also supports async interface, however, async
+> support for Transaction and Subscriber is still on the way.
+> 
+> The async interface depends on third-party event library, and so
+> far, only libuv is supported.
+
+Async code in redis-plus-plus looks like the following
+
+[source,cpp]
+----
+auto async_redis = AsyncRedis(opts, pool_opts);
+
+Future<string> ping_res = async_redis.ping();
+
+cout << ping_res.get() << endl;
+----
+
+As the reader can see, the async interface is based on futures
+which is also known to have a bad performance.  The biggest
+problem however with this async design is that it makes it
+impossible to write asynchronous programs correctly since it
+starts an async operation on every command sent instead of
+enqueueing a message and triggering a write when it can be sent.
+It is also not clear how are pipelines realised with this design
+(if at all).

doc/modules/ROOT/pages/examples.adoc

@@ -0,0 +1,27 @@
+//
+// Copyright (c) 2025 Marcelo Zimbres Silva (mzimbres@gmail.com)
+//
+// Distributed under the Boost Software License, Version 1.0. (See accompanying
+// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+//
+
+= Examples
+
+The examples below show how to use the features discussed throughout this documentation:
+
+* {site-url}/example/cpp20_intro.cpp[cpp20_intro.cpp]: Does not use awaitable operators.
+* {site-url}/example/cpp20_intro_tls.cpp[cpp20_intro_tls.cpp]: Communicates over TLS.
+* {site-url}/example/cpp20_unix_sockets.cpp[cpp20_unix_sockets.cpp]: Communicates over UNIX domain sockets.
+* {site-url}/example/cpp20_containers.cpp[cpp20_containers.cpp]: Shows how to send and receive STL containers and how to use transactions.
+* {site-url}/example/cpp20_json.cpp[cpp20_json.cpp]: Shows how to serialize types using Boost.Json.
+* {site-url}/example/cpp20_protobuf.cpp[cpp20_protobuf.cpp]: Shows how to serialize types using protobuf.
+* {site-url}/example/cpp20_sentinel.cpp[cpp20_sentinel.cpp]: Shows how to use the library with a Sentinel deployment.
+* {site-url}/example/cpp20_subscriber.cpp[cpp20_subscriber.cpp]: Shows how to implement pubsub with reconnection re-subscription.
+* {site-url}/example/cpp20_echo_server.cpp[cpp20_echo_server.cpp]: A simple TCP echo server.
+* {site-url}/example/cpp20_chat_room.cpp[cpp20_chat_room.cpp]: A command line chat built on Redis pubsub.
+* {site-url}/example/cpp17_intro.cpp[cpp17_intro.cpp]: Uses callbacks and requires pass:[C++17].
+* {site-url}/example/cpp17_intro_sync.cpp[cpp17_intro_sync.cpp]: Runs `async_run` in a separate thread and performs synchronous calls to `async_exec`.
+* {site-url}/example/cpp17_spdlog.cpp[cpp17_spdlog.cpp]: Shows how to use third-party logging libraries like `spdlog` with Boost.Redis.
+
+The main function used in some async examples has been factored out in
+the {site-url}/example/main.cpp[main.cpp] file.

doc/modules/ROOT/pages/index.adoc

@@ -0,0 +1,154 @@
+//
+// Copyright (c) 2025 Marcelo Zimbres Silva (mzimbres@gmail.com)
+//
+// Distributed under the Boost Software License, Version 1.0. (See accompanying
+// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+//
+
+[#intro]
+= Introduction
+
+Boost.Redis is a high-level https://redis.io/[Redis] and https://valkey.io/[Valkey]
+client library built on top of
+https://www.boost.org/doc/libs/latest/doc/html/boost_asio.html[Boost.Asio]
+that implements the Redis protocol
+https://github.com/redis/redis-specifications/blob/master/protocol/RESP3.md[RESP3].
+
+== Requirements
+
+The requirements for using Boost.Redis are:
+
+* Boost 1.84 or higher. Boost.Redis is included in Boost installations since Boost 1.84.
+* pass:[C++17] or higher. Supported compilers include gcc 11 and later, clang 11 and later, and Visual Studio 16 (2019) and later.
+* Redis 6 or higher, or Valkey (any version). The database server must support RESP3.
+  We intend to maintain compatibility with both Redis and Valkey in the long-run.
+* OpenSSL.
+
+The documentation assumes basic-level knowledge about https://redis.io/docs/[Redis] and https://www.boost.org/doc/libs/latest/doc/html/boost_asio.html[Boost.Asio].
+
+== Building the library
+
+To use the library it is necessary to include the following:
+
+[source,cpp]
+----
+#include <boost/redis/src.hpp>
+----
+
+in exactly one source file in your applications. Otherwise, the library is header-only.
+
+Boost.Redis unconditionally requires OpenSSL. Targets using Boost.Redis need to link
+to the OpenSSL libraries.
+
+== Tutorial
+
+The code below uses a short-lived connection to
+https://redis.io/commands/ping/[ping] a Redis server:
+
+
+[source,cpp]
+----
+#include <boost/redis/connection.hpp>
+#include <boost/asio/co_spawn.hpp>
+#include <boost/asio/consign.hpp>
+#include <boost/asio/detached.hpp>
+#include <iostream>
+
+namespace net = boost::asio;
+using boost::redis::request;
+using boost::redis::response;
+using boost::redis::config;
+using boost::redis::connection;
+
+auto co_main(config const& cfg) -> net::awaitable<void>
+{
+   auto conn = std::make_shared<connection>(co_await net::this_coro::executor);
+   conn->async_run(cfg, {}, net::consign(net::detached, conn));
+
+   // A request containing only a ping command.
+   request req;
+   req.push("PING", "Hello world");
+
+   // Response object.
+   response<std::string> resp;
+
+   // Executes the request.
+   co_await conn->async_exec(req, resp);
+   conn->cancel();
+
+   std::cout << "PING: " << std::get<0>(resp).value() << std::endl;
+}
+----
+
+The roles played by the `async_run` and `async_exec` functions are:
+
+* xref:reference:boost/redis/basic_connection/async_exec-02.adoc[`connection::async_exec`]: executes the commands contained in the
+  request and stores the individual responses in the response object. Can
+  be called from multiple places in your code concurrently.
+* xref:reference:boost/redis/basic_connection/async_run-04.adoc[`connection::async_run`]: keeps the connection healthy. It takes care of hostname resolution, session establishment, health-checks, reconnection and coordination of low-level read and write operations. It should be called only once per connection, regardless of the number of requests to execute.
+
+== Server pushes
+
+Redis servers can also send a variety of pushes to the client. Some of
+them are:
+
+* https://redis.io/docs/manual/pubsub/[Pubsub messages].
+* https://redis.io/docs/manual/keyspace-notifications/[Keyspace notifications].
+* https://redis.io/docs/manual/client-side-caching/[Client-side caching].
+
+The connection class supports server pushes by means of the
+xref:reference:boost/redis/basic_connection/async_receive.adoc[`connection::async_receive2`] function, which can be
+called in the same connection that is being used to execute commands.
+The coroutine below shows how to use it
+
+
+[source,cpp]
+----
+auto receiver(std::shared_ptr<connection> conn) -> asio::awaitable<void>
+{
+   generic_flat_response resp;
+   conn->set_receive_response(resp);
+
+   // Subscribe to the channel 'mychannel'. You can add any number of channels here.
+   request req;
+   req.subscribe({"mychannel"});
+   co_await conn->async_exec(req);
+
+   // You're now subscribed to 'mychannel'. Pushes sent over this channel will be stored
+   // in resp. If the connection encounters a network error and reconnects to the server,
+   // it will automatically subscribe to 'mychannel' again. This is transparent to the user.
+   // You need to use specialized request::subscribe() function (instead of request::push)
+   // to enable this behavior.
+
+   // Loop to read Redis push messages.
+   while (conn->will_reconnect()) {
+      // Wait for pushes
+      auto [ec] = co_await conn->async_receive2(asio::as_tuple);
+
+      // Check for errors and cancellations
+      if (ec) {
+         std::cerr << "Error during receive: " << ec << std::endl;
+         break;
+      }
+
+      // The response must be consumed without suspending the
+      // coroutine i.e. without the use of async operations.
+      for (auto const& elem : resp.value())
+         std::cout << elem.value << "\n";
+
+      std::cout << std::endl;
+
+      resp.value().clear();
+   }
+}
+----
+
+== Further reading
+
+Here is a list of topics that you might be interested in:
+
+* xref:cancellation.adoc[Setting timeouts to requests and managing cancellation].
+* xref:requests_responses.adoc[More on requests and responses].
+* xref:serialization.adoc[Serializing and parsing into custom types].
+* xref:logging.adoc[Configuring logging].
+* xref:examples.adoc[Examples].

doc/modules/ROOT/pages/logging.adoc

@@ -0,0 +1,45 @@
+//
+// Copyright (c) 2025 Marcelo Zimbres Silva (mzimbres@gmail.com),
+// Ruben Perez Hidalgo (rubenperez038 at gmail dot com)
+//
+// Distributed under the Boost Software License, Version 1.0. (See accompanying
+// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+//
+
+= Logging
+
+xref:reference:boost/redis/basic_connection/async_run-04.adoc[`connection::async_run`]
+is a complex algorithm, with features like built-in reconnection.
+This can make configuration problems, like a misconfigured hostname, difficult to debug -
+Boost.Redis will keep retrying to connect to the same hostname over and over.
+For this reason, Boost.Redis incorporates a lightweight logging solution, and
+*will log some status messages to stderr by default*.
+
+Logging can be customized by passing a
+xref:reference:boost/redis/logger.adoc[`logger`] object to the connection's constructor. For example, logging can be disabled by writing:
+
+[source,cpp]
+----
+asio::io_context ioc;
+connection conn {ioc, logger{logger::level::disabled}};
+----
+
+Every message logged by the library is attached a
+https://en.wikipedia.org/wiki/Syslog#Severity_level[syslog-like severity]
+tag (a xref:reference:boost/redis/logger/level.adoc[`logger::level`]).
+You can filter messages by severity by creating a `logger` with a specific level:
+
+[source,cpp]
+----
+asio::io_context ioc;
+
+// Logs to stderr messages with severity >= level::error.
+// This will hide all informational output.
+connection conn {ioc, logger{logger::level::error}};
+----
+
+The `logger` constructor accepts a `std::function<void(logger::level, std::string_view)>`
+as second argument. If supplied, Boost.Redis will call this function when logging
+instead of printing to stderr. This can be used to integrate third-party logging
+libraries. See our {site-url}/example/cpp17_spdlog.cpp[spdlog integration example]
+for sample code.

doc/modules/ROOT/pages/reference.adoc

@@ -0,0 +1,104 @@
+//
+// Copyright (c) 2025 Marcelo Zimbres Silva (mzimbres@gmail.com),
+// Ruben Perez Hidalgo (rubenperez038 at gmail dot com)
+//
+// Distributed under the Boost Software License, Version 1.0. (See accompanying
+// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+//
+
+[#reference]
+= Reference
+
+[width=100%,cols="5*"]
+|===
+
+| *Connections*
+| *Requests and responses*
+| *Adapters*
+| *RESP3 protocol*
+| *Unstable low-level APIs*
+
+|
+xref:reference:boost/redis/connection.adoc[`connection`]
+
+xref:reference:boost/redis/basic_connection.adoc[`basic_connection`]
+
+xref:reference:boost/redis/address.adoc[`address`]
+
+xref:reference:boost/redis/role.adoc[`role`]
+
+xref:reference:boost/redis/config.adoc[`config`]
+
+xref:reference:boost/redis/sentinel_config.adoc[`sentinel_config`]
+
+xref:reference:boost/redis/error.adoc[`error`]
+
+xref:reference:boost/redis/logger.adoc[`logger`]
+
+xref:reference:boost/redis/logger/level.adoc[`logger::level`]
+
+xref:reference:boost/redis/operation.adoc[`operation`]
+
+xref:reference:boost/redis/usage.adoc[`usage`]
+
+
+|
+xref:reference:boost/redis/ignore_t.adoc[`ignore_t`]
+
+xref:reference:boost/redis/ignore.adoc[`ignore`]
+
+xref:reference:boost/redis/request.adoc[`request`]
+
+xref:reference:boost/redis/request/config.adoc[`request::config`]
+
+xref:reference:boost/redis/response.adoc[`response`]
+
+xref:reference:boost/redis/generic_response.adoc[`generic_response`]
+
+xref:reference:boost/redis/generic_flat_response.adoc[`generic_flat_response`]
+
+xref:reference:boost/redis/consume_one-08.adoc[`consume_one`]
+
+
+|
+xref:reference:boost/redis/adapter/boost_redis_adapt.adoc[`boost_redis_adapt`]
+
+xref:reference:boost/redis/adapter/ignore.adoc[`adapter::ignore`]
+
+xref:reference:boost/redis/adapter/error.adoc[`adapter::error`]
+
+xref:reference:boost/redis/adapter/result.adoc[`adapter::result`]
+
+xref:reference:boost/redis/any_adapter.adoc[`any_adapter`]
+
+|
+xref:reference:boost/redis/resp3/basic_node.adoc[`resp3::basic_node`]
+
+xref:reference:boost/redis/resp3/node.adoc[`resp3::node`]
+
+xref:reference:boost/redis/resp3/node_view.adoc[`resp3::node_view`]
+
+xref:reference:boost/redis/resp3/basic_tree.adoc[`resp3::basic_tree`]
+
+xref:reference:boost/redis/resp3/tree.adoc[`resp3::tree`]
+
+xref:reference:boost/redis/resp3/view_tree.adoc[`resp3::view_tree`]
+
+xref:reference:boost/redis/resp3/flat_tree.adoc[`resp3::flat_tree`]
+
+xref:reference:boost/redis/resp3/boost_redis_to_bulk-08.adoc[`boost_redis_to_bulk`]
+
+xref:reference:boost/redis/resp3/type.adoc[`resp3::type`]
+
+xref:reference:boost/redis/resp3/is_aggregate.adoc[`resp3::is_aggregate`]
+
+
+|
+
+xref:reference:boost/redis/adapter/adapt2.adoc[`adapter::adapt2`]
+
+xref:reference:boost/redis/resp3/parser.adoc[`resp3::parser`]
+
+xref:reference:boost/redis/resp3/parse.adoc[`resp3::parse`]
+
+|===

doc/modules/ROOT/pages/requests_responses.adoc

@@ -0,0 +1,303 @@
+//
+// Copyright (c) 2025 Marcelo Zimbres Silva (mzimbres@gmail.com)
+//
+// Distributed under the Boost Software License, Version 1.0. (See accompanying
+// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+//
+
+= Requests and responses
+
+== Requests
+
+Redis requests are composed of one or more commands. In the
+Redis documentation, requests are called
+https://redis.io/topics/pipelining[pipelines]. For example:
+
+[source,cpp]
+----
+// Some example containers.
+std::list<std::string> list {...};
+std::map<std::string, mystruct> map { ...};
+
+// The request can contain multiple commands.
+request req;
+
+// Command with variable length of arguments.
+req.push("SET", "key", "some value", "EX", "2");
+
+// Pushes a list.
+req.push_range("SUBSCRIBE", list);
+
+// Same as above but as an iterator range.
+req.push_range("SUBSCRIBE", std::cbegin(list), std::cend(list));
+
+// Pushes a map.
+req.push_range("HSET", "key", map);
+----
+
+Sending a request to Redis is performed by
+xref:reference:boost/redis/basic_connection/async_exec-02.adoc[`connection::async_exec`]
+as already stated. Requests accept a xref:reference:boost/redis/request/config.adoc[`boost::redis::request::config`]
+object when constructed that dictates how requests are handled in situations like
+reconnection. The reader is advised to read it carefully.
+
+## Responses
+
+Boost.Redis uses the following strategy to deal with Redis responses:
+
+* xref:reference:boost/redis/response.adoc[`boost::redis::response`] should be used
+  when the request's number of commands is known at compile-time.
+* xref:reference:boost/redis/generic_response.adoc[`boost::redis::generic_response`] should be
+  used when the number of commands is dynamic.
+
+For example, the request below has three commands:
+
+[source,cpp]
+----
+request req;
+req.push("PING");
+req.push("INCR", "key");
+req.push("QUIT");
+----
+
+Therefore, its response will also contain three elements.
+The following response object can be used:
+
+[source,cpp]
+----
+response<std::string, int, std::string>
+----
+
+The response behaves as a `std::tuple` and must
+have as many elements as the request has commands (exceptions below).
+It is also necessary that each tuple element is capable of storing the
+response to the command it refers to, otherwise an error will occur.
+
+To ignore responses to individual commands in the request use the tag
+xref:reference:boost/redis/ignore_t.adoc[`boost::redis::ignore_t`]. For example:
+
+[source,cpp]
+----
+// Ignore the second and last responses.
+response<std::string, ignore_t, std::string, ignore_t>
+----
+
+The following table provides the RESP3-types returned by some Redis
+commands:
+
+[cols="3*"]
+|===
+
+| *Command* | *RESP3 type* | *Documentation*
+
+| `lpush`    | Number                              | https://redis.io/commands/lpush[]
+| `lrange`   | Array                               | https://redis.io/commands/lrange[]
+| `set`      | Simple-string, null or blob-string  | https://redis.io/commands/set[]
+| `get`      | Blob-string                         | https://redis.io/commands/get[]
+| `smembers` | Set                                 | https://redis.io/commands/smembers[]
+| `hgetall`  | Map                                 | https://redis.io/commands/hgetall[]
+
+|===
+
+To map these RESP3 types into a pass:[C++] data structure use the table below:
+
+[cols="3*"]
+|===
+
+| *RESP3 type*   | *Possible pass:[C++] type*                                        | *Type*
+
+| Simple-string  | `std::string`                                              | Simple
+| Simple-error   | `std::string`                                              | Simple
+| Blob-string    | `std::string`, `std::vector`                               | Simple
+| Blob-error     | `std::string`, `std::vector`                               | Simple
+| Number         | `long long`, `int`, `std::size_t`, `std::string`           | Simple
+| Double         | `double`, `std::string`                                    | Simple
+| Null           | `std::optional<T>`                                         | Simple
+| Array          | `std::vector`, `std::list`, `std::array`, `std::deque`     | Aggregate
+| Map            | `std::vector`, `std::map`, `std::unordered_map`            | Aggregate
+| Set            | `std::vector`, `std::set`, `std::unordered_set`            | Aggregate
+| Push           | `std::vector`, `std::map`, `std::unordered_map`            | Aggregate
+
+|===
+
+For example, the response to the request
+
+[source,cpp]
+----
+request req;
+req.push("HELLO", 3);
+req.push_range("RPUSH", "key1", vec);
+req.push_range("HSET", "key2", map);
+req.push("LRANGE", "key3", 0, -1);
+req.push("HGETALL", "key4");
+req.push("QUIT");
+----
+
+Can be read in the following response object:
+
+[source,cpp]
+----
+response<
+   redis::ignore_t,  // hello
+   int,              // rpush
+   int,              // hset
+   std::vector<T>,   // lrange
+   std::map<U, V>,   // hgetall
+   std::string       // quit
+> resp;
+----
+
+To execute the request and read the response use
+xref:reference:boost/redis/basic_connection/async_exec-02.adoc[`async_exec`]:
+
+[source,cpp]
+----
+co_await conn->async_exec(req, resp);
+----
+
+If the intention is to ignore responses altogether, use
+xref:reference:boost/redis/ignore.adoc[`ignore`]:
+
+[source,cpp]
+----
+// Ignores the response
+co_await conn->async_exec(req, ignore);
+----
+
+Responses that contain nested aggregates or heterogeneous data
+types will be given special treatment later in xref:#the-general-case[the general case].  As
+of this writing, not all RESP3 types are used by the Redis server,
+which means in practice users will be concerned with a reduced
+subset of the RESP3 specification.
+
+### Pushes
+
+Commands that have no response, like
+
+* `"SUBSCRIBE"`
+* `"PSUBSCRIBE"`
+* `"UNSUBSCRIBE"`
+
+must **NOT** be included in the response tuple. For example, the following request
+
+[source,cpp]
+----
+request req;
+req.push("PING");
+req.subscribe({"channel"});
+req.push("QUIT");
+----
+
+must be read in the response object `response<std::string, std::string>`.
+
+### Null
+
+It is not uncommon for apps to access keys that do not exist or that
+have already expired in the Redis server. To deal with these use cases,
+wrap the type within a `std::optional`:
+
+[source,cpp]
+----
+response<
+   std::optional<A>,
+   std::optional<B>,
+   ...
+   > resp;
+----
+
+Everything else stays the same.
+
+### Transactions
+
+To read responses to transactions we must first observe that Redis
+will queue the transaction commands and send their individual
+responses as elements of an array. The array itself is the response to
+the `EXEC` command.  For example, to read the response to this request
+
+[source,cpp]
+----
+req.push("MULTI");
+req.push("GET", "key1");
+req.push("LRANGE", "key2", 0, -1);
+req.push("HGETALL", "key3");
+req.push("EXEC");
+----
+
+Use the following response type:
+
+[source,cpp]
+----
+response<
+   ignore_t,  // multi
+   ignore_t,  // QUEUED
+   ignore_t,  // QUEUED
+   ignore_t,  // QUEUED
+   response<
+      std::optional<std::string>, // get
+      std::optional<std::vector<std::string>>, // lrange
+      std::optional<std::map<std::string, std::string>> // hgetall
+   > // exec
+> resp;
+----
+
+For a complete example, see {site-url}/example/cpp20_containers.cpp[cpp20_containers.cpp].
+
+[#the-general-case]
+### The general case
+
+There are cases where responses to Redis
+commands won't fit in the model presented above. Some examples are:
+
+* Commands (like `set`) whose responses don't have a fixed
+  RESP3 type. Expecting an `int` and receiving a blob-string
+  results in an error.
+* RESP3 aggregates that contain nested aggregates can't be read in STL containers.
+* Transactions with a dynamic number of commands can't be read in a `response`.
+
+To deal with these cases Boost.Redis provides the xref:reference:boost/redis/resp3/node.adoc[`boost::redis::resp3::node`] type
+abstraction, that is the most general form of an element in a
+response, be it a simple RESP3 type or the element of an aggregate. It
+is defined like:
+
+[source,cpp]
+----
+template <class String>
+struct basic_node {
+   // The RESP3 type of the data in this node.
+   type data_type;
+
+   // The number of elements of an aggregate (or 1 for simple data).
+   std::size_t aggregate_size;
+
+   // The depth of this node in the response tree.
+   std::size_t depth;
+
+   // The actual data. For aggregate types this is always empty.
+   String value;
+};
+----
+
+Any response to a Redis command can be parsed into a
+xref:reference:boost/redis/generic_response.adoc[boost::redis::generic_response]
+and its counterpart xref:reference:boost/redis/generic_flat_response.adoc[boost::redis::generic_flat_response].
+The vector can be seen as a pre-order view of the response tree.
+Using it is not different than using other types:
+
+[source,cpp]
+----
+// Receives any RESP3 simple or aggregate data type.
+boost::redis::generic_response resp;
+co_await conn->async_exec(req, resp);
+----
+
+For example, suppose we want to retrieve a hash data structure
+from Redis with `HGETALL`, some of the options are
+
+* `boost::redis::generic_response` and `boost::redis::generic_flat_response`: always works.
+* `std::vector<std::string>`: efficient and flat, all elements as string.
+* `std::map<std::string, std::string>`: efficient if you need the data as a `std::map`.
+* `std::map<U, V>`: efficient if you are storing serialized data. Avoids temporaries and requires `boost_redis_from_bulk` for `U` and `V`.
+
+In addition to the above users can also use unordered versions of the
+containers. The same reasoning applies to sets e.g. `SMEMBERS`
+and other data structures in general.

doc/modules/ROOT/pages/sentinel.adoc

@@ -0,0 +1,152 @@
+//
+// Copyright (c) 2025 Marcelo Zimbres Silva (mzimbres@gmail.com),
+// Ruben Perez Hidalgo (rubenperez038 at gmail dot com)
+//
+// Distributed under the Boost Software License, Version 1.0. (See accompanying
+// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+//
+
+= Sentinel
+
+Boost.Redis supports Redis Sentinel deployments. Sentinel handling
+in `connection` is built-in: xref:reference:boost/redis/basic_connection/async_run-04.adoc[`async_run`]
+automatically connects to Sentinels, resolves the master's address, and connects to the master.
+
+Configuration is done using xref:reference:boost/redis/sentinel_config.adoc[`config::sentinel`]:
+
+[source,cpp]
+----
+config cfg;
+
+// To enable Sentinel, set this field to a non-empty list
+// of (hostname, port) pairs where Sentinels are listening
+cfg.sentinel.addresses = {
+    {"sentinel1.example.com", "26379"},
+    {"sentinel2.example.com", "26379"},
+    {"sentinel3.example.com", "26379"},
+};
+
+// Set master_name to the identifier that you configured
+// in the "sentinel monitor" statement of your sentinel.conf file
+cfg.sentinel.master_name = "mymaster";
+----
+
+Once set, the connection object can be used normally. See our
+our {site-url}/example/cpp20_sentinel.cpp[Sentinel example]
+for a full program.
+
+== Connecting to replicas
+
+By default, the library connects to the Redis master.
+You can connect to one of its replicas by using
+xref:reference:boost/redis/sentinel_config/server_role.adoc[`config::sentinel::server_role`].
+This can be used to balance load, if all your commands read data from
+the server and never write to it. The particular replica will be chosen randomly.
+
+[source,cpp]
+----
+config cfg;
+
+// Set up Sentinel
+cfg.sentinel.addresses = {
+    {"sentinel1.example.com", "26379"},
+    {"sentinel2.example.com", "26379"},
+    {"sentinel3.example.com", "26379"},
+};
+cfg.sentinel.master_name = "mymaster";
+
+// Ask the library to connect to a random replica of 'mymaster', rather than the master node
+cfg.sentinel.server_role = role::replica;
+----
+
+
+== Sentinel authentication
+
+If your Sentinels require authentication, 
+you can use xref:reference:boost/redis/sentinel_config/setup.adoc[`config::sentinel::setup`]
+to provide credentials.
+This request is executed immediately after connecting to Sentinels, and
+before any other command:
+
+[source,cpp]
+----
+// Set up Sentinel
+config cfg;
+cfg.sentinel.addresses = {
+    {"sentinel1.example.com", "26379"},
+    {"sentinel2.example.com", "26379"},
+    {"sentinel3.example.com", "26379"},
+};
+cfg.sentinel.master_name = "mymaster";
+
+// By default, setup contains a 'HELLO 3' command.
+// Override it to add an AUTH clause to it with out credentials.
+cfg.sentinel.setup.clear();
+cfg.sentinel.setup.push("HELLO", 3, "AUTH", "sentinel_user", "sentinel_password");
+
+// cfg.sentinel.setup applies to Sentinels, only.
+// Use cfg.setup to authenticate to masters/replicas.
+cfg.use_setup = true; // Required for cfg.setup to be used, for historic reasons
+cfg.setup.clear();
+cfg.setup.push("HELLO", 3, "AUTH", "master_user", "master_password");
+----
+
+== Using TLS with Sentinels
+
+You might use TLS with Sentinels only, masters/replicas only, or both by adjusting
+xref:reference:boost/redis/sentinel_config/use_ssl.adoc[`config::sentinel::use_ssl`]
+and xref:reference:boost/redis/config/use_ssl.adoc[`config::use_ssl`]:
+
+[source,cpp]
+----
+// Set up Sentinel
+config cfg;
+cfg.sentinel.addresses = {
+    {"sentinel1.example.com", "26379"},
+    {"sentinel2.example.com", "26379"},
+    {"sentinel3.example.com", "26379"},
+};
+cfg.sentinel.master_name = "mymaster";
+
+// Adjust these switches to enable/disable TLS
+cfg.use_ssl = true;          // Applies to masters and replicas
+cfg.sentinel.use_ssl = true; // Applies to Sentinels
+----
+
+== Sentinel algorithm
+
+This section details how `async_run` interacts with Sentinel.
+Most of the algorithm follows
+https://redis.io/docs/latest/develop/reference/sentinel-clients/[the official Sentinel client guidelines].
+Some of these details may vary between library versions.
+
+* Connections maintain an internal list of Sentinels, bootstrapped from
+  xref:reference:boost/redis/sentinel_config/addresses.adoc[`config::sentinel::addresses`].
+* The first Sentinel in the list is contacted by performing the following:
+** A physical connection is established.
+** The setup request is executed.
+** The master's address is resolved using
+   https://redis.io/docs/latest/operate/oss_and_stack/management/sentinel/#sentinel-api[`SENTINEL GET-MASTER-NAME-BY-ADDR`].
+** If `config::sentinel::server_role` is `role::replica`, replica addresses are obtained using
+   https://redis.io/docs/latest/operate/oss_and_stack/management/sentinel/#sentinel-api[`SENTINEL REPLICAS`].
+   One replica is chosen randomly.
+** The address of other Sentinels also monitoring this master are retrieved using
+   https://redis.io/docs/latest/operate/oss_and_stack/management/sentinel/#sentinel-api[`SENTINEL SENTINELS`].
+* If a Sentinel is unreachable, doesn't know about the configured master,
+  or returns an error while executing the above requests, the next Sentinel in the list is tried.
+* If all Sentinels have been tried without success, `config::reconnect_wait_interval`
+  is waited, and the process starts again.
+* After a successful Sentinel response, the internal Sentinel list is updated
+  with any newly discovered Sentinels.
+  Sentinels in `config::sentinel::addresses` are always kept in the list,
+  even if they weren't present in the output of `SENTINEL SENTINELS`.
+* The retrieved address is used
+  to establish a connection with the master or replica.
+  A `ROLE` command is added at the end of the setup request.
+  This is used to detect situations where a Sentinel returns outdated
+  information due to a failover in process. If `ROLE` doesn't output
+  the expected role (`"master"` or `"slave"`, depending on `config::sentinel::server_role`)
+  `config::reconnect_wait_interval` is waited and Sentinel is contacted again.
+* The connection to the master/replica is run like any other connection.
+  If network errors or timeouts happen, `config::reconnect_wait_interval`
+  is waited and Sentinel is contacted again.

doc/modules/ROOT/pages/serialization.adoc

@@ -0,0 +1,26 @@
+//
+// Copyright (c) 2025 Marcelo Zimbres Silva (mzimbres@gmail.com)
+//
+// Distributed under the Boost Software License, Version 1.0. (See accompanying
+// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+//
+
+= Serializing and parsing into custom types
+
+Boost.Redis supports serialization of user defined types by means of
+the following customization points
+
+[source,cpp]
+----
+// Serialize
+void boost_redis_to_bulk(std::string& to, mystruct const& obj);
+
+// Deserialize
+void boost_redis_from_bulk(mystruct& u, node_view const& node, boost::system::error_code&);
+----
+
+These functions are accessed over ADL and therefore they must be
+imported in the global namespace by the user. The following examples might be of interest:
+
+* {site-url}/example/cpp20_json.cpp[cpp20_json.cpp]: serializes and parses JSON objects.
+* {site-url}/example/cpp20_protobuf.cpp[cpp20_protobuf.cpp]: serializes and parses https://protobuf.dev/[protobuf] objects.

doc/mrdocs.cpp

@@ -0,0 +1,10 @@
+//
+// Copyright (c) 2025 Ruben Perez Hidalgo (rubenperez038 at gmail dot com)
+//
+// Distributed under the Boost Software License, Version 1.0. (See accompanying
+// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+//
+
+#define BOOST_ALLOW_DEPRECATED  // avoid mrdocs errors with the BOOST_DEPRECATED macro
+
+#include <boost/redis.hpp>

doc/mrdocs.yml

@@ -0,0 +1,31 @@
+#
+# Copyright (c) 2025 Ruben Perez Hidalgo (rubenperez038 at gmail dot com)
+#
+# Distributed under the Boost Software License, Version 1.0. (See accompanying
+# file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+#
+
+source-root: ../include
+compilation-database: ./CMakeLists.txt
+include-symbols:
+  - "boost::redis::**"
+exclude-symbols:
+  - "boost::redis::detail::**"
+  - "boost::redis::adapter::detail::**"
+  - "boost::redis::resp3::detail::**"
+  - "boost::redis::basic_connection::run_is_canceled"
+  - "boost::redis::basic_connection::this_type"
+  - "boost::redis::any_adapter::impl_t"
+  - "boost::redis::any_adapter::fn_type"
+  - "boost::redis::any_adapter::create_impl"
+  - "boost::redis::any_adapter::impl_"
+  - "boost::redis::request::payload"
+  - "boost::redis::request::has_hello_priority"
+see-below:
+  - "boost::redis::adapter::ignore"
+sort-members: false
+base-url: https://github.com/boostorg/redis/blob/master/include/
+use-system-libc: true
+warn-as-error: true
+warn-if-undocumented: false
+warn-no-paramdoc: false

doc/on-the-costs-of-async-abstractions.md

@@ -0,0 +1,671 @@
+# On the costs of asynchronous abstractions
+
+The biggest force behind the evolution of
+[Boost.Redis](https://github.com/boostorg/redis) was my struggling in
+coming up with a high-level connection abstraction that was capable of
+multiplexing Redis commands from independent sources while
+concurrently handling server pushes. This journey taught me many
+important lessons, many of which are related to the design and
+performance of asynchronous programs based on Boost.Asio.
+
+In this article I will share some of the lessons learned, specially
+those related to the performance costs of _abstractions_ such as
+`async_read_until` that tend to overschedule into the event-loop. In
+this context I will also briefly comment on how the topics discussed
+here influenced my views on the proposed
+[P2300](https://www.open-std.org/jtc1/sc22/wg21/docs/papers/2023/p2300r7.html)
+(a.k.a. Senders and Receivers), which is likely to become the basis of
+networking in upcoming C++ standards.
+
+Although the analysis presented in this article uses the Redis communication
+protocol for illustration I expect it to be useful in general since
+[RESP3](https://github.com/antirez/RESP3/blob/master/spec.md) shares
+many similarities with other widely used protocols such as HTTP. 
+
+## Parsing `\r\n`-delimited messages
+
+The Redis server communicates with its clients by exchanging data
+serialized in
+[RESP3](https://github.com/antirez/RESP3/blob/master/spec.md) format.
+Among the data types supported by this specification, the
+`\r\n`-delimited messages are some of the most frequent in a typical
+session. The table below shows some examples
+
+  Command  | Response | Wire format   | RESP3 name
+  ---------|----------|---------------|---------------------
+  PING     |  PONG    | `+PONG\r\n`   | simple-string
+  INCR     |  42      | `:42\r\n`     | number
+  GET      |  null    | `_\r\n`       | null
+
+Redis also supports command pipelines, which provide a way of
+optimizing round-trip times by batching commands. A pipeline composed
+by the commands shown in the previous table look like this
+
+```
+                       |   Sent in a     |
+                       |   single write  |
++--------+             |                 |              +-------+
+|        | -------->    PING + INCR + GET     --------> |       |
+|        |                                              |       |
+| Client |                                              | Redis |
+|        |                                              |       |
+|        | <-------- "+PONG\r\n:42\r\n_\r\n"  <-------- |       |
++--------+            |<------>|<---->|<-->|            +-------+
+                      |                    |
+                      |     Responses      |
+```
+
+Messages that use delimiters are so common in networking that a
+facility called `async_read_until` for reading them incrementally from
+a socket is already part of Boost.Asio. The coroutine below uses it to
+print message contents to the screen
+
+```cpp
+awaitable<void> parse_resp3_simple_msgs(tcp::socket socket)
+{
+  for (std::string buffer;;) {
+     auto n = co_await async_read_until(socket, dynamic_buffer(buffer), "\r\n");
+
+     std::cout << buffer.substr(1, n - 3) << std::endl;
+
+     // Consume the buffer.
+     buffer.erase(0, n);
+  }
+}
+```
+
+If we pay attention to the buffer content as it is parsed by the code
+above we can see it is rotated fairly often, for example
+
+```
+   "+PONG\r\n:100\r\n+OK\r\n_\r\n"
+   ":100\r\n+OK\r\n_\r\n"
+   "+OK\r\n_\r\n"
+   "_\r\n"
+   ""
+```
+
+When I first realized these, apparently excessive, buffer rotations I
+was concerned they would impact the performance of Boost.Redis in a
+severe way.  To measure the magnitude of this impact I came up with an
+experimental implementation of Asio's `dynamic_buffer` that consumed
+the buffer less eagerly than the `std::string::erase` function used
+above. For that, the implementation increased a buffer offset up
+to a certain threshold and only then triggered a (larger) rotation.
+This is illustrated in the diagram below
+
+```
+    |<---- offset threshold ---->|
+    |                            |
+   "+PONG\r\n:100\r\n+OK\r\n_\r\n+PONG\r\n"
+    |                                       # Initial offset
+
+   "+PONG\r\n:100\r\n+OK\r\n_\r\n+PONG\r\n"
+    |<------>|                              # After 1st message
+
+   "+PONG\r\n:100\r\n+OK\r\n_\r\n+PONG\r\n"
+    |<-------------->|                      # After 2nd message
+
+   "+PONG\r\n:100\r\n+OK\r\n_\r\n+PONG\r\n"
+    |<--------------------->|               # After 3rd message
+
+   "+PONG\r\n:100\r\n+OK\r\n_\r\n+PONG\r\n"
+    |<-------------------------->|          # Threshold crossed after the 4th message
+
+   "+PONG\r\n"
+    |                                       # After rotation
+```
+
+After comparing the performance differences between the two versions I
+was surprised there wasn't any! But that was also very suspicious
+since some RESP3 aggregate types contain a considerable number of
+separators.  For example, a map with two pairs `[(key1, value1),
+(key2, value2)]` encoded in RESP3 requires ten rotations in total
+
+```
+   "%2\r\n$4\r\nkey1\r\n$6\r\nvalue1\r\n$4\r\nkey2\r\n$6\r\nvalue2\r\n"
+   "$4\r\nkey1\r\n$6\r\nvalue1\r\n$4\r\nkey2\r\n$6\r\nvalue2\r\n"
+   "key1\r\n$6\r\nvalue1\r\n$4\r\nkey2\r\n$6\r\nvalue2\r\n"
+   "$6\r\nvalue1\r\n$4\r\nkey2\r\n$6\r\nvalue2\r\n"
+   ...
+```
+
+It was evident something more costly was shadowing the buffer
+rotations. But it couldn't be the search for the separator since it
+performs equivalently to rotations. It is also easy to show that the
+overhead is not related to any IO operation since the problem persists
+if the buffer is never consumed (which causes the function to be
+called with the same string repeatedly).  Once these two factors
+are removed from the table, we are driven into the conclusion that
+calling `async_read_until` has an intrinsic cost, let us see what
+that is.
+
+### Async operations that complete synchronously considered harmful
+
+Assume the scenario described earlier where `async_read_until` is used
+to parse multiple `\r\n`-delimited messages. The following is a
+detailed description of what happens behind the scenes
+
+   1. `async_read_until` calls `socket.async_read_some` repeatedly
+      until the separator `\r\n` shows up in the buffer
+
+```
+   "<read1>"                                # Read 1: needs more data.
+   "<read1><read2>"                         # Read 2: needs more data.
+   "<read1><read2>"                         # Read 3: needs more data.
+   "<read1><read2><read3>"                  # Read 4: needs more data.
+   "<read1><read2><read3>\r\n<bonus bytes>" # separator found, done.
+```
+
+   2. The last call to `socket.async_read_some` happens to read past
+      the separator `\r\n` (depicted as `<bonus bytes>` above),
+      resulting in bonus (maybe incomplete) messages in the buffer
+
+```
+    | 1st async_read_some  |         2nd async_read_some            |
+    |                      |                                        |
+    "+message content here \r\n:100\r\n+OK\r\n_\r\n+incomplete respo"
+    |                          |                   |                |
+    |      Message wanted      |<-- bonus msgs --->|<--incomplete-->|
+    |                          |                         msg        |
+    |                          |                                    |
+    |                          |<---------- bonus bytes ----------->|
+```
+
+   3. The buffer is consumed and `async_read_until` is called again.
+      However, since the buffer already contains the next message this
+      is an IO-less call
+
+```
+   ":100\r\n+OK\r\n_\r\n+not enough byt"
+    |                   |              |
+    |  No IO required   | Need more    |
+    |  to parse these   | data         |   
+    |  messages.        |              |
+```
+
+The fact that step 3. doesn't perform any IO implies the operation can
+complete synchronously, but because this is an asynchronous function
+Boost.Asio by default won't call the continuation before the
+function returns. The implementation must therefore enqueue it for
+execution, as depicted below
+
+```
+   OP5 ---> OP4 ---> OP3 ---> OP2 ---> OP1    # Reschedules the continuation
+                                        |
+       OP1 schedules its continuation   |
+    +-----------------------------------+
+    |
+    |
+   OP6 ---> OP5 ---> OP4 ---> OP3 ---> OP2    # Reschedules the continuation
+                                        |
+       OP2 schedules its continuation   |
+    +-----------------------------------+
+    |
+    |
+   OP7 ---> OP6 ---> OP5 ---> OP4 ---> OP3    
+```
+
+When summed up, the excessive rescheduling of continuations lead to
+performance degradation at scale. But since this is an event-loop
+there is no way around rescheduling as doing otherwise would mean
+allowing a task to monopolize the event-loop, preventing other tasks
+from making progress. The best that can be done is to avoid
+_overscheduling_, so let us determine how much rescheduling is too
+much.
+
+## The intrinsic latency of an event-loop 
+
+An event-loop is a design pattern originally used to handle events
+external to the application, such as GUIs, networking and other forms
+of IO.  If we take this literally, it becomes evident that the way
+`async_read_until` works is incompatible with an event-loop since
+_searching for the separator_ is not an external event and as such
+should not have to be enqueued for execution.
+
+Once we constrain ourselves to events that have an external origin,
+such as anything related to IO and including any form of IPC, the
+scheduling overhead is reduced considerably since the latency
+of the transport layer eclipses whatever time it takes to schedule the
+continuation, for example, according to
+[these](https://www.boost.org/doc/libs/develop/libs/cobalt/doc/html/index.html#posting_to_an_executor)
+benchmarks, the time it takes to schedule a task in the
+`asio::io_context ` is approximately `50ns`.
+
+To give the reader an idea about the magnitude of this number, if
+rescheduling alone were to account for 1% of the runtime of an app
+that uses asynchronous IO to move around data in chunks of size 128kb,
+then this app would have a throughput of approximately 24Gbs.  At such
+high throughput multiple other factors kick in before any scheduling
+overhead even starts to manifest.
+
+It is therefore safe to say that only asynchronous operations that
+don't perform or are not bound to any IO are ever likely to
+overschedule in the sense described above. Those cases can be usually
+avoided, this is what worked for Boost.Redis
+
+  1. `async_read_until` was replaced with calls to
+     `socket.async_read_some` and an incremental parser that does not
+     do any IO.
+
+  2. Channel `try_` functions are used to check if send and receive
+     operations can be called without suspension. For example,
+     `try_send` before `async_send` and `try_receive` before
+     `async_receive` ([see also](https://github.com/chriskohlhoff/asio/commit/fe4fd7acf145335eeefdd19708483c46caeb45e5)
+     `try_send_via_dispatch` for a more aggressive optimization).
+
+  3. Coalescing of individual requests into a single payload to reduce
+     the number of necessary writes on the socket, this is only
+     possible because Redis supports pipelining (good protocols
+     help!).
+
+  4. Increased the socket read sizes to 4kb to reduce the number of
+     reads (which is outweighed by the costs of rotating data in the
+     buffer).
+
+  5. Dropped the `resp3::async_read` abstraction. When I started
+     developing Boost.Redis there was convincing precedent for having
+     a `resp3::async_read` function to read complete RESP3 messages
+     from a socket
+
+     Name                                   | Description
+     ---------------------------------------|-------------------
+     `asio::ip::tcp::async_read`            | Reads `n` bytes from a stream.
+     `beast::http::async_read`              | Reads a complete HTTP message.
+     `beast::websocket::stream::async_read` | Reads a complete Websocket message.
+     `redis::async_read`                    | Reads a complete RESP3 message.
+
+     It turns out however that this function is also vulnerable to
+     immediate completions since in command pipelines multiple
+     responses show up in the buffer after a call to
+     `socket.async_read_some`. When that happens each call to
+     `resp3::async_read` is IO-less.
+   
+Sometimes it is not possible to avoid asynchronous operations that
+complete synchronously, in the following sections we will see how to
+favor throughput over fairness in Boost.Asio.
+
+### Calling the continuation inline
+
+In Boost.Asio it is possible to customize how an algorithm executes
+the continuation when an immediate completion occurs, this includes
+the ability of calling it inline, thereby avoiding the costs of
+excessive rescheduling.  Here is how it works
+
+```cpp
+// (default) The continuation is enqueued for execution, regardless of
+// whether it is immediate or not.
+async_read_until(socket, buffer, "\r\n", continuation);
+
+// Immediate completions are executed in exec2 (otherwise equal to the
+// version above). The completion is called inline if exec2 is the
+// same executor that is running the operation.
+async_read_until(socket, buffer, "\r\n", bind_immediate_executor(exec2, completion));
+```
+
+To compare the performance of both cases I have written a small
+function that calls `async_read_until` in a loop with a buffer that is
+never consumed so that all completions are immediate.  The version
+below uses the default behaviour
+
+```cpp
+void read_safe(tcp::socket& s, std::string& buffer)
+{
+   auto continuation = [&s, &buffer](auto ec, auto n)
+   {
+      read_safe(s, buffer); // Recursive call
+   };
+
+   // This won't cause stack exhaustion because the continuation is 
+   // not called inline but posted in the event loop.
+   async_read_until(s, dynamic_buffer(buffer), "\r\n", continuation);
+}
+```
+
+To optimize away some of the rescheduling the version below uses the
+`bind_immediate_executor` customization to call the continuation
+reentrantly and then breaks the stack from time to time to avoid
+exhausting it
+
+```cpp
+void read_reentrant(tcp::socket& s, std::string& buffer)
+{
+   auto cont = [&](auto, auto)
+   {
+      read_reentrant(s, buffer); // Recursive call
+   };
+
+   // Breaks the callstack after 16 inline calls.
+   if (counter % 16 == 0) {
+      post(s.get_executor(), [cont](){cont({}, 0);});
+      return;
+   }
+
+   // Continuation called reentrantly.
+   async_read_until(s, dynamic_buffer(buffer), "\r\n",
+      bind_immediate_executor(s.get_executor(), cont));
+}
+```
+
+The diagram below shows what the reentrant chain of calls in the code
+above look like from the event-loop point of view
+
+```
+   OP5 ---> OP4 ---> OP3 ---> OP2 ---> OP1a    # Completes immediately
+                                        |
+                                        |      
+                 ...                    |
+                                       OP1b    # Completes immediately
+                                        |
+           Waiting for OP5 to           |      
+             reschedule its             |
+             continuation              OP1c    # Completes immediately
+                                        |
+                                        |      
+                 ...                    |
+                                       OP1d    # Break the call-stack
+                                        |
+    +-----------------------------------+     
+    |
+   OP6 ---> OP5 ---> OP4 ---> OP3 ---> OP2
+```
+
+Unsurprisingly, the reentrant code is 3x faster than the one that
+relies on the default behaviour (don't forget that this is a best case
+scenario, in the general case not all completions are immediate).
+Although faster, this strategy has some downsides
+
+   - The overall operation is not as fast as possible since it still
+     has to reschedule from time to time to break the call stack.  The
+     less it reschedules the higher the risk of exhausting it.
+
+   - It is too easy to forget to break the stack. For example, the
+     programmer might decide to branch somewhere into another chain of
+     asynchronous calls that also use this strategy.  To avoid
+     exhaustion all such branches would have to be safeguarded with a
+     manual rescheduling i.e. `post`.
+
+   - Requires additional layers of complexity such as
+     `bind_immediate_executor` in addition to `bind_executor`.
+   
+  - Non-compliat with more strict
+    [guidelines](https://en.wikipedia.org/wiki/The_Power_of_10:_Rules_for_Developing_Safety-Critical_Code)
+    that prohibits reentrat code.
+
+   - There is no simple way of choosing the maximum allowed number of
+     reentrant calls for each function in a way that covers different
+     use cases and users. Library writers and users would be tempted
+     into using a small value reducing the performance advantage.
+
+   - If the socket is always ready for reading the task will
+     monopolize IO for up to `16` interactions which might cause
+     stutter in unrelated tasks as depicted below
+
+```
+                                 Unfairness
+
+          +----+----+----+    +----+----+----+    +----+----+----+
+Socket-1  |    |    |    |    |    |    |    |    |    |    |    |
+          +----+----+----+----+----+----+----+----+----+----+----+----+     
+Socket-2                 |    |              |    |              |    | 
+                         +----+              +----+              +----+
+```
+
+From the aesthetic point of view the code above is also unpleasant as
+it breaks the function asynchronous contract by injecting a reentrant
+behaviour. It gives me the same kind of feeling I have about
+[recursive
+mutexes](http://www.zaval.org/resources/library/butenhof1.html).
+
+Note: It is worth mentioning here that a similar
+[strategy](https://github.com/NVIDIA/stdexec/blob/6f23dd5b1d523541ce28af32fc2603403ebd36ed/include/exec/trampoline_scheduler.hpp#L52)
+is used to break the call stack of repeating algorithms in
+[stdexec](https://github.com/NVIDIA/stdexec), but in this time
+based on
+[P2300](https://www.open-std.org/jtc1/sc22/wg21/docs/papers/2023/p2300r7.html)
+and not on Boost.Asio.
+
+### Coroutine tail-calls
+
+In the previous section we have seen how to avoid overscheduling by
+instructing the asynchronous operation to call the completion inline
+on immediate completion.  It turns out however that coroutine support
+for _tail-calls_ provide a way to completely sidestep this problem.
+This feature is described by
+[Lewis Baker](https://lewissbaker.github.io/2020/05/11/understanding_symmetric_transfer)
+as follows
+
+> A tail-call is one where the current stack-frame is popped before
+> the call and the current function’s return address becomes the
+> return-address for the callee. ie. the callee will return directly
+> the the [sic] caller of this function.
+
+This means (at least in principle) that a library capable of using
+tail-calls when an immediate completion occurs neither has to
+reschedule the continuation nor call it inline. To test how this
+feature compares to the other styles I have used Boost.Cobalt. The
+code looks as follows
+
+```cpp
+// Warning: risks unfairness and starvation of other tasks.
+task<void> read_until_unfair()
+{
+    for (int i = 0; i != repeat; ++i) {
+        co_await async_read_until(s, dynamic_buffer(buffer), "\r\n", cobalt::use_op);
+    }
+}
+```
+
+The result of this comparison as listed in the table below
+
+Time/s | Style     | Configuration               | Library     
+-------|-----------|-----------------------------|-------------
+ 1,0   | Coroutine | `await_ready` optimization  | Boost.Cobalt
+ 4.8   | Callback  | Reentant                    | Boost.Asio  
+10.3   | Coroutine | `use_op`                    | Boost.Cobalt
+14.9   | Callback  | Regular                     | Boost.Asio  
+15.6   | Coroutine | `asio::deferred`            | Boost.Asio  
+
+As the reader can see, `cobalt::use_op` ranks 3rd and is considerably
+faster (10.3 vs 15.6) than the Asio equivalent that uses
+default-rescheduling. However, by trading rescheduling with tail-calls
+the code above can now monopolize the event-loop, resulting in
+unfairness if the socket happens to receive data at a higher rate
+than other tasks. If by chance data is received continuously
+on a socket that is always ready for reading, other tasks will starve
+
+```
+                                 Starvation
+
+          +----+----+----+----+----+----+----+----+----+----+----+----+
+Socket-1  |    |    |    |    |    |    |    |    |    |    |    |    |
+          +----+----+----+----+----+----+----+----+----+----+----+----+     
+
+Socket-2          Starving ...                                          
+                                                                       
+```
+
+To avoid this problem the programmer is forced to reschedule from time
+to time, in the same way we did for the reentrant calls
+
+```cpp
+task<void> read_until_fair()
+{
+    for (int i = 0; i != repeat; ++i) {
+        if (repeat % 16 == 0) {
+            // Reschedules to address unfairness and starvation of 
+            // other tasks.
+            co_await post(cobalt::use_op);
+            continue;
+        }
+        
+        co_await async_read_until(s, dynamic_buffer(buffer), "\r\n", cobalt::use_op);
+    }
+}
+```
+
+Delegating fairness-safety to applications is a dangerous game.
+This is a
+[problem](https://tokio.rs/blog/2020-04-preemption) the Tokio
+community had to deal with before Tokio runtime started enforcing
+rescheduling (after 256 successful operations)
+
+> If data is received faster than it can be processed, it is possible
+> that more data will have already been received by the time the
+> processing of a data chunk completes. In this case, .await will
+> never yield control back to the scheduler, other tasks will not be
+> scheduled, resulting in starvation and large latency variance.
+
+> Currently, the answer to this problem is that the user of Tokio is
+> responsible for adding yield points in both the application and
+> libraries. In practice, very few actually do this and end up being
+> vulnerable to this sort of problem.
+
+### Safety in P2300 (Senders and Receivers)
+
+As of this writing, the C++ standards committee (WG21) has been
+pursuing the standardization of a networking library for almost 20
+years. One of the biggest obstacles that prevented it from happening
+was a disagreement on what the _asynchronous model_ that underlies
+networking should look like. Until 2021 that model was basically
+Boost.Asio _executors_,  but in this
+[poll](https://www.reddit.com/r/cpp/comments/q6tgod/c_committee_polling_results_for_asynchronous/)
+the committee decided to abandon that front and concentrate efforts on
+the new [P2300](https://www.open-std.org/jtc1/sc22/wg21/docs/papers/2023/p2300r7.html)
+proposal, also known as _senders and receivers_. The decision was
+quite [abrupt](https://isocpp.org/files/papers/P2464R0.html)
+
+> The original plan about a week earlier than the actual writing of
+> this paper was to write a paper that makes a case for standardizing
+> the Networking TS.
+
+and opinions turned out to be very strong against Boost.Asio (see
+[this](https://api.csswg.org/bikeshed/?force=1&url=https://raw.githubusercontent.com/brycelelbach/wg21_p2459_2022_january_library_evolution_poll_outcomes/main/2022_january_library_evolution_poll_outcomes.bs)
+for how each voter backed their vote)
+
+> The whole concept is completely useless, there's no composed code
+> you can write with it.
+
+The part of that debate that interests us most here is stated in
+[P2471](https://www.open-std.org/jtc1/sc22/wg21/docs/papers/2021/p2471r1.pdf),
+that compares Boost.Asio with P2300
+
+> Yes, default rescheduling each operation and default not
+> rescheduling each operation, is a poor trade off. IMO both options
+> are poor. The one good option that I know of that can prevent stack
+> exhaustion is first-class tail-recursion in library or language
+
+> ASIO has chosen to require that every async operation must schedule
+> the completion on a scheduler (every read, every write, etc..).
+
+> sender/receiver has not decided to
+> require that the completion be scheduled. 
+
+> This is why I consider tail-call the only good solution. Scheduling
+> solutions are all inferior (give thanks to Lewis for this shift in
+> my understanding :) ).
+
+Although tail-calls solve the problem of stack-exhaustion as we have
+seen above, it makes the code vulnerable to unfairness and starvation
+and therefore it is not an alternative to default-rescheduling as the
+quotation above is implying.  To deal with the lack of
+default-rescheduling, libraries and applications built on top of P2300
+have to address the aforementioned problems, layer after layer. For
+example,
+[stdexec](https://github.com/NVIDIA/stdexec) has invented something
+called
+_[trampoline-scheduler](https://github.com/NVIDIA/stdexec/blob/e7cd275273525dbc693f4bf5f6dc4d4181b639e4/include/exec/trampoline_scheduler.hpp)_
+to protect repeating algorithms such as `repeat_effect_until` from
+exhausting the stack. This construct however is built around
+reentracy, allowing
+[sixteen](https://github.com/NVIDIA/stdexec/blob/83cdb92d316e8b3bca1357e2cf49fc39e9bed403/include/exec/trampoline_scheduler.hpp#L52)
+levels of inline calls by default. While in Boost.Asio it is possible to use
+reentracy as an optimization for a corner cases, here it is made its
+_modus operandi_, the downsides of this approach have already been stated in a
+previous section so I won't repeat it here.
+
+Also the fact that a special scheduler is needed by specific
+algorithms is a problem on its own since it contradicts one of the
+main selling points of P2300 which is that of being _generic_. For
+example, [P2464R0](https://isocpp.org/files/papers/P2464R0.html) uses
+the code below as an example
+
+```cpp
+void
+run_that_io_operation(
+    scheduler auto sched,
+    sender_of<network_buffer> auto wrapping_continuation)
+{
+   // snip
+}
+```
+
+and states
+
+> I have no idea what the sched's concrete type is. I have no idea
+> what the wrapping_continuation's concrete type is. They're none of
+> my business, ...
+
+Hence, by being generic, the algorithms built on top of P2300 are also
+unsafe (against stack-exhaustion, unfairness and starvation).  Otherwise,
+if library writers require a specific scheduler to ensure safety, then
+the algorithms become automatically non-generic, pick your poison!
+
+The proposers of P2300 claim that it doesn't address safety because it
+should be seen as the low-level building blocks of asynchronous
+programming and that its the role of higher-level libraries, to deal
+with that. This claim however does not hold since, as we have just
+seen, Boost.Asio also provides those building blocks but does so in a
+safe way.  In fact during the whole development of Boost.Redis I never
+had to think about these kinds of problems because safety is built
+from the ground up.
+
+### Avoiding coroutine suspension with `await_ready`
+
+Now let us get back to the first place in the table above, which uses
+the `await_ready` optimization from Boost.Cobalt. This API provides
+users with the ability to avoid coroutine suspension altogether in
+case the separator is already present in the buffer.  It works by
+defining a `struct` with the following interface
+
+```cpp
+struct read_until : cobalt::op<error_code, std::size_t> {
+   ...
+
+   void ready(cobalt::handler<error_code, std::size_t> handler) override
+   {
+      // Search for the separator in buffer and call the handler if found
+   }
+
+   void initiate(cobalt::completion_handler<error_code, std::size_t> complete) override
+   {
+      // Regular call to async_read_until.
+      async_read_until(socket, buffer, delim, std::move(complete));
+   }
+};
+```
+
+and the code that uses it
+
+```cpp
+for (int i = 0; i != repeat; ++i) {
+    co_await read_until(socket, dynamic_buffer(buffer));
+}
+```
+
+In essence, what the code above does is to skip a call to
+`async_read_unil` by first checking with the ready function whether
+the forthcoming operation is going to complete immediately.  The
+nice thing about it is that the programmer can use this optimization
+only when a performance bottleneck is detected, without planing for it
+in advance.  The drawback however is that it requires reimplementing
+the search for the separator in the body of the `ready` function,
+defeating the purpose of using `async_read_until` in first place as
+(again) it would have been simpler to reformulate the operation in
+terms of `socket.async_read_some` directly.
+
+## Acknowledgements
+
+Thanks to Klemens Morgenstern for answering questions about
+Boost.Cobalt.
+

doc/package.json

@@ -0,0 +1,6 @@
+{
+  "dependencies": {
+    "@cppalliance/antora-cpp-reference-extension": "^0.0.6",
+    "antora": "^3.1.10"
+  }
+}

doc/redis-playbook.yml

@@ -0,0 +1,45 @@
+#
+# Copyright (c) 2025 Ruben Perez Hidalgo (rubenperez038 at gmail dot com)
+#
+# Distributed under the Boost Software License, Version 1.0. (See accompanying
+# file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+#
+
+site:
+  url: https://github.com/boostorg/redis/blob/master
+  title: Boost.Redis
+  robots: allow
+  start_page: redis::index.adoc
+
+antora:
+  extensions:
+    - require: '@cppalliance/antora-cpp-reference-extension'
+      dependencies:
+        - name: 'boost'
+          repo: 'https://github.com/boostorg/boost.git'
+          tag: 'develop'
+          variable: 'BOOST_SRC_DIR'
+          system-env: 'BOOST_SRC_DIR'
+
+asciidoc:
+  attributes:
+    # Scrolling problems appear without this
+    page-pagination: ''
+
+content:
+  sources:
+    - url: ..
+      start_path: doc
+
+ui: 
+  bundle:
+    url: https://github.com/boostorg/website-v2-docs/releases/download/ui-master/ui-bundle.zip
+    snapshot: true
+  output_dir: _
+
+output:
+  dir: html
+
+runtime:
+  log:
+    failure_level: error

example/CMakeLists.txt

@@ -10,13 +10,14 @@ macro(make_example EXAMPLE_NAME STANDARD)
   if (${STANDARD} STREQUAL "20")
     target_link_libraries(${EXAMPLE_NAME} PRIVATE examples_main)
   endif()
+  if (${EXAMPLE_NAME} STREQUAL "cpp20_json")
+    target_link_libraries(${EXAMPLE_NAME} PRIVATE Boost::json Boost::container_hash)
+  endif()
 endmacro()
 
 macro(make_testable_example EXAMPLE_NAME STANDARD)
   make_example(${EXAMPLE_NAME} ${STANDARD})
-  if (BOOST_REDIS_INTEGRATION_TESTS)
-    add_test(${EXAMPLE_NAME} ${EXAMPLE_NAME})
-  endif()
+  add_test(${EXAMPLE_NAME} ${EXAMPLE_NAME} $ENV{BOOST_REDIS_TEST_SERVER} 6379)
 endmacro()
 
 make_testable_example(cpp17_intro 17)
@@ -25,12 +26,14 @@ make_testable_example(cpp17_intro_sync 17)
 make_testable_example(cpp20_intro 20)
 make_testable_example(cpp20_containers 20)
 make_testable_example(cpp20_json 20)
-make_testable_example(cpp20_intro_tls 20)
+make_testable_example(cpp20_unix_sockets 20)
+make_testable_example(cpp20_timeouts 20)
+make_testable_example(cpp20_sentinel 20)
 
 make_example(cpp20_subscriber 20)
 make_example(cpp20_streams 20)
 make_example(cpp20_echo_server 20)
-make_example(cpp20_resolve_with_sentinel 20)
+make_example(cpp20_intro_tls 20)
 
 # We test the protobuf example only on gcc.
 if (CMAKE_CXX_COMPILER_ID STREQUAL "GNU")
@@ -46,4 +49,13 @@ endif()
 
 if (NOT MSVC)
   make_example(cpp20_chat_room 20)
-endif()
+endif()
+
+# We build and test the spdlog integration example only if the library is found
+find_package(spdlog)
+if (spdlog_FOUND)
+  make_testable_example(cpp17_spdlog 17)
+  target_link_libraries(cpp17_spdlog PRIVATE spdlog::spdlog)
+else()
+  message(STATUS "Skipping the spdlog example because the spdlog package couldn't be found")
+endif()

example/cpp17_intro.cpp

@@ -5,7 +5,9 @@
  */
 
 #include <boost/redis/connection.hpp>
+
 #include <boost/asio/detached.hpp>
+
 #include <iostream>
 
 namespace asio = boost::asio;
@@ -14,7 +16,7 @@ using boost::redis::request;
 using boost::redis::response;
 using boost::redis::config;
 
-auto main(int argc, char * argv[]) -> int
+auto main(int argc, char* argv[]) -> int
 {
    try {
       config cfg;
@@ -32,7 +34,7 @@ auto main(int argc, char * argv[]) -> int
       asio::io_context ioc;
       connection conn{ioc};
 
-      conn.async_run(cfg, {}, asio::detached);
+      conn.async_run(cfg, asio::detached);
 
       conn.async_exec(req, resp, [&](auto ec, auto) {
          if (!ec)
@@ -47,4 +49,3 @@ auto main(int argc, char * argv[]) -> int
       return 1;
    }
 }
-

example/cpp17_intro_sync.cpp

@@ -6,15 +6,15 @@
 
 #include "sync_connection.hpp"
 
-#include <string>
 #include <iostream>
+#include <string>
 
 using boost::redis::sync_connection;
 using boost::redis::request;
 using boost::redis::response;
 using boost::redis::config;
 
-auto main(int argc, char * argv[]) -> int
+auto main(int argc, char* argv[]) -> int
 {
    try {
       config cfg;

example/cpp17_spdlog.cpp

@@ -0,0 +1,99 @@
+//
+// Copyright (c) 2025 Marcelo Zimbres Silva (mzimbres@gmail.com),
+// Ruben Perez Hidalgo (rubenperez038 at gmail dot com)
+//
+// Distributed under the Boost Software License, Version 1.0. (See accompanying
+// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+//
+
+#include <boost/redis/connection.hpp>
+#include <boost/redis/logger.hpp>
+
+#include <boost/asio/detached.hpp>
+#include <boost/system/error_code.hpp>
+
+#include <cstddef>
+#include <iostream>
+#include <spdlog/spdlog.h>
+#include <string_view>
+
+namespace asio = boost::asio;
+namespace redis = boost::redis;
+
+// Maps a Boost.Redis log level to a spdlog log level
+static spdlog::level::level_enum to_spdlog_level(redis::logger::level lvl)
+{
+   switch (lvl) {
+      // spdlog doesn't include the emerg and alert syslog levels,
+      // so we convert them to the highest supported level.
+      // Similarly, notice is similar to info
+      case redis::logger::level::emerg:
+      case redis::logger::level::alert:
+      case redis::logger::level::crit:    return spdlog::level::critical;
+      case redis::logger::level::err:     return spdlog::level::err;
+      case redis::logger::level::warning: return spdlog::level::warn;
+      case redis::logger::level::notice:
+      case redis::logger::level::info:    return spdlog::level::info;
+      case redis::logger::level::debug:
+      default:                            return spdlog::level::debug;
+   }
+}
+
+// This function glues Boost.Redis logging and spdlog.
+// It should have the signature shown here. It will be invoked
+// by Boost.Redis whenever a message is to be logged.
+static void do_log(redis::logger::level level, std::string_view msg)
+{
+   spdlog::log(to_spdlog_level(level), "(Boost.Redis) {}", msg);
+}
+
+auto main(int argc, char** argv) -> int
+{
+   try {
+      // Create an execution context, required to create any I/O objects
+      asio::io_context ioc;
+
+      // Create a connection to connect to Redis, and pass it a custom logger.
+      // Boost.Redis will call do_log whenever it needs to log a message.
+      // Note that the function will only be called for messages with level >= info
+      // (i.e. filtering is done by Boost.Redis).
+      redis::connection conn{
+         ioc,
+         redis::logger{redis::logger::level::info, do_log}
+      };
+
+      // Configuration to connect to the server. Adjust as required
+      redis::config cfg;
+      if (argc == 3) {
+         cfg.addr.host = argv[1];
+         cfg.addr.port = argv[2];
+      }
+
+      // Run the connection with the specified configuration.
+      // This will establish the connection and keep it healthy
+      conn.async_run(cfg, asio::detached);
+
+      // Execute a request
+      redis::request req;
+      req.push("PING", "Hello world");
+
+      redis::response<std::string> resp;
+
+      conn.async_exec(req, resp, [&](boost::system::error_code ec, std::size_t /* bytes_read*/) {
+         if (ec) {
+            spdlog::error("Request failed: {}", ec.what());
+            exit(1);
+         } else {
+            spdlog::info("PING: {}", std::get<0>(resp).value());
+         }
+         conn.cancel();
+      });
+
+      // Actually run our example. Nothing will happen until we call run()
+      ioc.run();
+
+   } catch (std::exception const& e) {
+      spdlog::error("Error: {}", e.what());
+      return 1;
+   }
+}

example/cpp20_chat_room.cpp

@@ -1,38 +1,38 @@
-/* Copyright (c) 2018-2022 Marcelo Zimbres Silva (mzimbres@gmail.com)
+/* Copyright (c) 2018-2025 Marcelo Zimbres Silva (mzimbres@gmail.com)
  *
  * Distributed under the Boost Software License, Version 1.0. (See
  * accompanying file LICENSE.txt)
  */
 
 #include <boost/redis/connection.hpp>
-#include <boost/asio/deferred.hpp>
-#include <boost/asio/signal_set.hpp>
+
+#include <boost/asio/as_tuple.hpp>
 #include <boost/asio/co_spawn.hpp>
+#include <boost/asio/consign.hpp>
 #include <boost/asio/detached.hpp>
-#include <boost/asio/redirect_error.hpp>
 #include <boost/asio/posix/stream_descriptor.hpp>
-#include <unistd.h>
+#include <boost/asio/read_until.hpp>
+#include <boost/asio/signal_set.hpp>
+
+#include <exception>
 #include <iostream>
+#include <unistd.h>
 
 #if defined(BOOST_ASIO_HAS_CO_AWAIT)
 #if defined(BOOST_ASIO_HAS_POSIX_STREAM_DESCRIPTOR)
 
 namespace asio = boost::asio;
-using stream_descriptor = asio::deferred_t::as_default_on_t<asio::posix::stream_descriptor>;
-using signal_set = asio::deferred_t::as_default_on_t<asio::signal_set>;
+using asio::posix::stream_descriptor;
+using asio::signal_set;
 using boost::asio::async_read_until;
 using boost::asio::awaitable;
 using boost::asio::co_spawn;
 using boost::asio::consign;
-using boost::asio::deferred;
 using boost::asio::detached;
 using boost::asio::dynamic_buffer;
-using boost::asio::redirect_error;
-using boost::asio::use_awaitable;
 using boost::redis::config;
 using boost::redis::connection;
-using boost::redis::generic_response;
-using boost::redis::ignore;
+using boost::redis::generic_flat_response;
 using boost::redis::request;
 using boost::system::error_code;
 using namespace std::chrono_literals;
@@ -40,47 +40,62 @@ using namespace std::chrono_literals;
 // Chat over Redis pubsub. To test, run this program from multiple
 // terminals and type messages to stdin.
 
-auto
-receiver(std::shared_ptr<connection> conn) -> awaitable<void>
-{
-   request req;
-   req.push("SUBSCRIBE", "channel");
+namespace {
 
-   generic_response resp;
+auto rethrow_on_error = [](std::exception_ptr exc) {
+   if (exc)
+      std::rethrow_exception(exc);
+};
+
+auto receiver(std::shared_ptr<connection> conn) -> awaitable<void>
+{
+   // Set the receive response, so pushes are stored in resp
+   generic_flat_response resp;
    conn->set_receive_response(resp);
 
+   // Subscribe to the channel 'channel'. Using request::subscribe()
+   // (instead of request::push()) makes the connection re-subscribe
+   // to 'channel' whenever it re-connects to the server.
+   request req;
+   req.subscribe({"channel"});
+   co_await conn->async_exec(req);
+
    while (conn->will_reconnect()) {
+      // Wait for pushes
+      auto [ec] = co_await conn->async_receive2(asio::as_tuple);
 
-      // Subscribe to channels.
-      co_await conn->async_exec(req, ignore, deferred);
-
-      // Loop reading Redis push messages.
-      for (error_code ec;;) {
-         co_await conn->async_receive(redirect_error(use_awaitable, ec));
-         if (ec)
-            break; // Connection lost, break so we can reconnect to channels.
-         std::cout
-            << resp.value().at(1).value
-            << " " << resp.value().at(2).value
-            << " " << resp.value().at(3).value
-            << std::endl;
-         resp.value().clear();
+      // Check for errors and cancellations
+      if (ec) {
+         std::cerr << "Error during receive: " << ec << std::endl;
+         break;
       }
+
+      // The response must be consumed without suspending the
+      // coroutine i.e. without the use of async operations.
+      for (auto const& elem : resp.value())
+         std::cout << elem.value << "\n";
+
+      std::cout << std::endl;
+
+      resp.value().clear();
    }
 }
 
 // Publishes stdin messages to a Redis channel.
-auto publisher(std::shared_ptr<stream_descriptor> in, std::shared_ptr<connection> conn) -> awaitable<void>
+auto publisher(std::shared_ptr<stream_descriptor> in, std::shared_ptr<connection> conn)
+   -> awaitable<void>
 {
    for (std::string msg;;) {
       auto n = co_await async_read_until(*in, dynamic_buffer(msg, 1024), "\n");
       request req;
       req.push("PUBLISH", "channel", msg);
-      co_await conn->async_exec(req, ignore, deferred);
+      co_await conn->async_exec(req);
       msg.erase(0, n);
    }
 }
 
+}  // namespace
+
 // Called from the main function (see main.cpp)
 auto co_main(config cfg) -> awaitable<void>
 {
@@ -88,9 +103,9 @@ auto co_main(config cfg) -> awaitable<void>
    auto conn = std::make_shared<connection>(ex);
    auto stream = std::make_shared<stream_descriptor>(ex, ::dup(STDIN_FILENO));
 
-   co_spawn(ex, receiver(conn), detached);
-   co_spawn(ex, publisher(stream, conn), detached);
-   conn->async_run(cfg, {}, consign(detached, conn));
+   co_spawn(ex, receiver(conn), rethrow_on_error);
+   co_spawn(ex, publisher(stream, conn), rethrow_on_error);
+   conn->async_run(cfg, consign(detached, conn));
 
    signal_set sig_set{ex, SIGINT, SIGTERM};
    co_await sig_set.async_wait();
@@ -98,11 +113,11 @@ auto co_main(config cfg) -> awaitable<void>
    stream->cancel();
 }
 
-#else // defined(BOOST_ASIO_HAS_POSIX_STREAM_DESCRIPTOR)
+#else   // defined(BOOST_ASIO_HAS_POSIX_STREAM_DESCRIPTOR)
 auto co_main(config const&) -> awaitable<void>
 {
    std::cout << "Requires support for posix streams." << std::endl;
    co_return;
 }
-#endif // defined(BOOST_ASIO_HAS_POSIX_STREAM_DESCRIPTOR)
-#endif // defined(BOOST_ASIO_HAS_CO_AWAIT)
+#endif  // defined(BOOST_ASIO_HAS_POSIX_STREAM_DESCRIPTOR)
+#endif  // defined(BOOST_ASIO_HAS_CO_AWAIT)

example/cpp20_containers.cpp

@@ -1,16 +1,18 @@
-/* Copyright (c) 2018-2022 Marcelo Zimbres Silva (mzimbres@gmail.com)
+/* Copyright (c) 2018-2025 Marcelo Zimbres Silva (mzimbres@gmail.com)
  *
  * Distributed under the Boost Software License, Version 1.0. (See
  * accompanying file LICENSE.txt)
  */
 
 #include <boost/redis/connection.hpp>
-#include <boost/asio/deferred.hpp>
-#include <boost/asio/detached.hpp>
+
 #include <boost/asio/co_spawn.hpp>
+#include <boost/asio/consign.hpp>
+#include <boost/asio/detached.hpp>
+
+#include <iostream>
 #include <map>
 #include <vector>
-#include <iostream>
 
 #if defined(BOOST_ASIO_HAS_CO_AWAIT)
 
@@ -22,36 +24,51 @@ using boost::redis::ignore;
 using boost::redis::config;
 using boost::redis::connection;
 using boost::asio::awaitable;
-using boost::asio::deferred;
 using boost::asio::detached;
 using boost::asio::consign;
 
+template <class T>
+std::ostream& operator<<(std::ostream& os, std::optional<T> const& opt)
+{
+   if (opt.has_value())
+      std::cout << opt.value();
+   else
+      std::cout << "null";
+
+   return os;
+}
+
 void print(std::map<std::string, std::string> const& cont)
 {
-   for (auto const& e: cont)
+   for (auto const& e : cont)
       std::cout << e.first << ": " << e.second << "\n";
 }
 
-void print(std::vector<int> const& cont)
+template <class T>
+void print(std::vector<T> const& cont)
 {
-   for (auto const& e: cont) std::cout << e << " ";
+   for (auto const& e : cont)
+      std::cout << e << " ";
    std::cout << "\n";
 }
 
 // Stores the content of some STL containers in Redis.
 auto store(std::shared_ptr<connection> conn) -> awaitable<void>
 {
-   std::vector<int> vec
-      {1, 2, 3, 4, 5, 6};
+   std::vector<int> vec{1, 2, 3, 4, 5, 6};
 
-   std::map<std::string, std::string> map
-      {{"key1", "value1"}, {"key2", "value2"}, {"key3", "value3"}};
+   std::map<std::string, std::string> map{
+      {"key1", "value1"},
+      {"key2", "value2"},
+      {"key3", "value3"}
+   };
 
    request req;
    req.push_range("RPUSH", "rpush-key", vec);
    req.push_range("HSET", "hset-key", map);
+   req.push("SET", "key", "value");
 
-   co_await conn->async_exec(req, ignore, deferred);
+   co_await conn->async_exec(req, ignore);
 }
 
 auto hgetall(std::shared_ptr<connection> conn) -> awaitable<void>
@@ -64,7 +81,22 @@ auto hgetall(std::shared_ptr<connection> conn) -> awaitable<void>
    response<std::map<std::string, std::string>> resp;
 
    // Executes the request and reads the response.
-   co_await conn->async_exec(req, resp, deferred);
+   co_await conn->async_exec(req, resp);
+
+   print(std::get<0>(resp).value());
+}
+
+auto mget(std::shared_ptr<connection> conn) -> awaitable<void>
+{
+   // A request contains multiple commands.
+   request req;
+   req.push("MGET", "key", "non-existing-key");
+
+   // Responses as tuple elements.
+   response<std::vector<std::optional<std::string>>> resp;
+
+   // Executes the request and reads the response.
+   co_await conn->async_exec(req, resp);
 
    print(std::get<0>(resp).value());
 }
@@ -74,33 +106,41 @@ auto transaction(std::shared_ptr<connection> conn) -> awaitable<void>
 {
    request req;
    req.push("MULTI");
-   req.push("LRANGE", "rpush-key", 0, -1); // Retrieves
-   req.push("HGETALL", "hset-key"); // Retrieves
+   req.push("LRANGE", "rpush-key", 0, -1);  // Retrieves
+   req.push("HGETALL", "hset-key");         // Retrieves
+   req.push("MGET", "key", "non-existing-key");
    req.push("EXEC");
 
    response<
-      ignore_t, // multi
-      ignore_t, // lrange
-      ignore_t, // hgetall
-      response<std::optional<std::vector<int>>, std::optional<std::map<std::string, std::string>>> // exec
-   > resp;
+      ignore_t,  // multi
+      ignore_t,  // lrange
+      ignore_t,  // hgetall
+      ignore_t,  // mget
+      response<
+         std::optional<std::vector<int>>,
+         std::optional<std::map<std::string, std::string>>,
+         std::optional<std::vector<std::optional<std::string>>>>  // exec
+      >
+      resp;
 
-   co_await conn->async_exec(req, resp, deferred);
+   co_await conn->async_exec(req, resp);
 
-   print(std::get<0>(std::get<3>(resp).value()).value().value());
-   print(std::get<1>(std::get<3>(resp).value()).value().value());
+   print(std::get<0>(std::get<4>(resp).value()).value().value());
+   print(std::get<1>(std::get<4>(resp).value()).value().value());
+   print(std::get<2>(std::get<4>(resp).value()).value().value());
 }
 
 // Called from the main function (see main.cpp)
 awaitable<void> co_main(config cfg)
 {
    auto conn = std::make_shared<connection>(co_await asio::this_coro::executor);
-   conn->async_run(cfg, {}, consign(detached, conn));
+   conn->async_run(cfg, consign(detached, conn));
 
    co_await store(conn);
    co_await transaction(conn);
    co_await hgetall(conn);
+   co_await mget(conn);
    conn->cancel();
 }
 
-#endif // defined(BOOST_ASIO_HAS_CO_AWAIT)
+#endif  // defined(BOOST_ASIO_HAS_CO_AWAIT)

example/cpp20_echo_server.cpp

@@ -5,19 +5,20 @@
  */
 
 #include <boost/redis/connection.hpp>
-#include <boost/asio/deferred.hpp>
-#include <boost/asio/signal_set.hpp>
-#include <boost/asio/detached.hpp>
-#include <boost/asio/redirect_error.hpp>
+
 #include <boost/asio/co_spawn.hpp>
+#include <boost/asio/consign.hpp>
+#include <boost/asio/detached.hpp>
+#include <boost/asio/read_until.hpp>
+#include <boost/asio/redirect_error.hpp>
+#include <boost/asio/signal_set.hpp>
+
 #include <iostream>
 
 #if defined(BOOST_ASIO_HAS_CO_AWAIT)
 
 namespace asio = boost::asio;
-using tcp_socket = asio::deferred_t::as_default_on_t<asio::ip::tcp::socket>;
-using tcp_acceptor = asio::deferred_t::as_default_on_t<asio::ip::tcp::acceptor>;
-using signal_set = asio::deferred_t::as_default_on_t<asio::signal_set>;
+using boost::asio::signal_set;
 using boost::redis::request;
 using boost::redis::response;
 using boost::redis::config;
@@ -25,7 +26,8 @@ using boost::system::error_code;
 using boost::redis::connection;
 using namespace std::chrono_literals;
 
-auto echo_server_session(tcp_socket socket, std::shared_ptr<connection> conn) -> asio::awaitable<void>
+auto echo_server_session(asio::ip::tcp::socket socket, std::shared_ptr<connection> conn)
+   -> asio::awaitable<void>
 {
    request req;
    response<std::string> resp;
@@ -33,7 +35,7 @@ auto echo_server_session(tcp_socket socket, std::shared_ptr<connection> conn) ->
    for (std::string buffer;;) {
       auto n = co_await asio::async_read_until(socket, asio::dynamic_buffer(buffer, 1024), "\n");
       req.push("PING", buffer);
-      co_await conn->async_exec(req, resp, asio::deferred);
+      co_await conn->async_exec(req, resp);
       co_await asio::async_write(socket, asio::buffer(std::get<0>(resp).value()));
       std::get<0>(resp).value().clear();
       req.clear();
@@ -46,7 +48,7 @@ auto listener(std::shared_ptr<connection> conn) -> asio::awaitable<void>
 {
    try {
       auto ex = co_await asio::this_coro::executor;
-      tcp_acceptor acc(ex, {asio::ip::tcp::v4(), 55555});
+      asio::ip::tcp::acceptor acc(ex, {asio::ip::tcp::v4(), 55555});
       for (;;)
          asio::co_spawn(ex, echo_server_session(co_await acc.async_accept(), conn), asio::detached);
    } catch (std::exception const& e) {
@@ -60,11 +62,11 @@ auto co_main(config cfg) -> asio::awaitable<void>
    auto ex = co_await asio::this_coro::executor;
    auto conn = std::make_shared<connection>(ex);
    asio::co_spawn(ex, listener(conn), asio::detached);
-   conn->async_run(cfg, {}, asio::consign(asio::detached, conn));
+   conn->async_run(cfg, asio::consign(asio::detached, conn));
 
    signal_set sig_set(ex, SIGINT, SIGTERM);
    co_await sig_set.async_wait();
    conn->cancel();
 }
 
-#endif // defined(BOOST_ASIO_HAS_CO_AWAIT)
+#endif  // defined(BOOST_ASIO_HAS_CO_AWAIT)

example/cpp20_intro.cpp

@@ -5,10 +5,11 @@
  */
 
 #include <boost/redis/connection.hpp>
-#include <boost/asio/deferred.hpp>
+
 #include <boost/asio/co_spawn.hpp>
-#include <boost/asio/detached.hpp>
 #include <boost/asio/consign.hpp>
+#include <boost/asio/detached.hpp>
+
 #include <iostream>
 
 #if defined(BOOST_ASIO_HAS_CO_AWAIT)
@@ -23,7 +24,7 @@ using boost::redis::connection;
 auto co_main(config cfg) -> asio::awaitable<void>
 {
    auto conn = std::make_shared<connection>(co_await asio::this_coro::executor);
-   conn->async_run(cfg, {}, asio::consign(asio::detached, conn));
+   conn->async_run(cfg, asio::consign(asio::detached, conn));
 
    // A request containing only a ping command.
    request req;
@@ -33,10 +34,10 @@ auto co_main(config cfg) -> asio::awaitable<void>
    response<std::string> resp;
 
    // Executes the request.
-   co_await conn->async_exec(req, resp, asio::deferred);
+   co_await conn->async_exec(req, resp);
    conn->cancel();
 
    std::cout << "PING: " << std::get<0>(resp).value() << std::endl;
 }
 
-#endif // defined(BOOST_ASIO_HAS_CO_AWAIT)
+#endif  // defined(BOOST_ASIO_HAS_CO_AWAIT)

example/cpp20_intro_tls.cpp

@@ -5,10 +5,12 @@
  */
 
 #include <boost/redis/connection.hpp>
-#include <boost/asio/deferred.hpp>
-#include <boost/asio/use_awaitable.hpp>
-#include <boost/asio/detached.hpp>
+
 #include <boost/asio/consign.hpp>
+#include <boost/asio/detached.hpp>
+#include <boost/asio/ssl/context.hpp>
+#include <boost/asio/use_awaitable.hpp>
+
 #include <iostream>
 
 #if defined(BOOST_ASIO_HAS_CO_AWAIT)
@@ -34,21 +36,22 @@ auto co_main(config cfg) -> asio::awaitable<void>
    cfg.addr.host = "db.occase.de";
    cfg.addr.port = "6380";
 
-   auto conn = std::make_shared<connection>(co_await asio::this_coro::executor);
-   conn->async_run(cfg, {}, asio::consign(asio::detached, conn));
+   asio::ssl::context ctx{asio::ssl::context::tlsv12_client};
+   ctx.set_verify_mode(asio::ssl::verify_peer);
+   ctx.set_verify_callback(verify_certificate);
+
+   auto conn = std::make_shared<connection>(co_await asio::this_coro::executor, std::move(ctx));
+   conn->async_run(cfg, asio::consign(asio::detached, conn));
 
    request req;
    req.push("PING");
 
    response<std::string> resp;
 
-   conn->next_layer().set_verify_mode(asio::ssl::verify_peer);
-   conn->next_layer().set_verify_callback(verify_certificate);
-
-   co_await conn->async_exec(req, resp, asio::deferred);
+   co_await conn->async_exec(req, resp);
    conn->cancel();
 
    std::cout << "Response: " << std::get<0>(resp).value() << std::endl;
 }
 
-#endif // defined(BOOST_ASIO_HAS_CO_AWAIT)
+#endif  // defined(BOOST_ASIO_HAS_CO_AWAIT)

example/cpp20_json.cpp

@@ -5,33 +5,35 @@
  */
 
 #include <boost/redis/connection.hpp>
-#include <boost/asio/deferred.hpp>
-#include <boost/asio/detached.hpp>
-#include <boost/describe.hpp>
+
 #include <boost/asio/consign.hpp>
+#include <boost/asio/detached.hpp>
 #include <boost/asio/use_awaitable.hpp>
-#include <string>
+#include <boost/describe.hpp>
+
 #include <iostream>
+#include <string>
 
 #if defined(BOOST_ASIO_HAS_CO_AWAIT)
 
-#define BOOST_JSON_NO_LIB
-#define BOOST_CONTAINER_NO_LIB
-#include <boost/json/serialize.hpp>
-#include <boost/json/parse.hpp>
-#include <boost/json/value_from.hpp>
 #include <boost/redis/resp3/serialization.hpp>
-#include <boost/json/src.hpp>
+
+#include <boost/json/parse.hpp>
+#include <boost/json/serialize.hpp>
+#include <boost/json/value_from.hpp>
+#include <boost/json/value_to.hpp>
 
 namespace asio = boost::asio;
+namespace resp3 = boost::redis::resp3;
 using namespace boost::describe;
 using boost::redis::request;
 using boost::redis::response;
 using boost::redis::ignore_t;
 using boost::redis::config;
 using boost::redis::connection;
+using boost::redis::resp3::node_view;
 
-// Struct that will be stored in Redis using json serialization. 
+// Struct that will be stored in Redis using json serialization.
 struct user {
    std::string name;
    std::string age;
@@ -43,35 +45,38 @@ BOOST_DESCRIBE_STRUCT(user, (), (name, age, country))
 
 // Boost.Redis customization points (example/json.hpp)
 void boost_redis_to_bulk(std::string& to, user const& u)
-   { boost::redis::resp3::boost_redis_to_bulk(to, boost::json::serialize(boost::json::value_from(u))); }
+{
+   resp3::boost_redis_to_bulk(to, boost::json::serialize(boost::json::value_from(u)));
+}
 
-void boost_redis_from_bulk(user& u, std::string_view sv, boost::system::error_code&)
-   { u = boost::json::value_to<user>(boost::json::parse(sv)); }
+void boost_redis_from_bulk(user& u, node_view const& node, boost::system::error_code&)
+{
+   u = boost::json::value_to<user>(boost::json::parse(node.value));
+}
 
 auto co_main(config cfg) -> asio::awaitable<void>
 {
    auto ex = co_await asio::this_coro::executor;
    auto conn = std::make_shared<connection>(ex);
-   conn->async_run(cfg, {}, asio::consign(asio::detached, conn));
+   conn->async_run(cfg, asio::consign(asio::detached, conn));
 
    // user object that will be stored in Redis in json format.
    user const u{"Joao", "58", "Brazil"};
 
    // Stores and retrieves in the same request.
    request req;
-   req.push("SET", "json-key", u); // Stores in Redis.
-   req.push("GET", "json-key"); // Retrieves from Redis.
+   req.push("SET", "json-key", u);  // Stores in Redis.
+   req.push("GET", "json-key");     // Retrieves from Redis.
 
    response<ignore_t, user> resp;
 
-   co_await conn->async_exec(req, resp, asio::deferred);
+   co_await conn->async_exec(req, resp);
    conn->cancel();
 
    // Prints the first ping
-   std::cout
-      << "Name: " << std::get<1>(resp).value().name << "\n"
-      << "Age: " << std::get<1>(resp).value().age << "\n"
-      << "Country: " << std::get<1>(resp).value().country << "\n";
+   std::cout << "Name: " << std::get<1>(resp).value().name << "\n"
+             << "Age: " << std::get<1>(resp).value().age << "\n"
+             << "Country: " << std::get<1>(resp).value().country << "\n";
 }
 
-#endif // defined(BOOST_ASIO_HAS_CO_AWAIT)
+#endif  // defined(BOOST_ASIO_HAS_CO_AWAIT)

example/cpp20_protobuf.cpp

@@ -6,11 +6,12 @@
 
 #include <boost/redis/connection.hpp>
 #include <boost/redis/resp3/serialization.hpp>
-#include <boost/asio/deferred.hpp>
+
 #include <boost/asio/co_spawn.hpp>
-#include <boost/asio/detached.hpp>
 #include <boost/asio/consign.hpp>
+#include <boost/asio/detached.hpp>
 #include <boost/system/errc.hpp>
+
 #include <iostream>
 
 // See the definition in person.proto. This header is automatically
@@ -20,19 +21,20 @@
 #if defined(BOOST_ASIO_HAS_CO_AWAIT)
 
 namespace asio = boost::asio;
+namespace resp3 = boost::redis::resp3;
 using boost::redis::request;
 using boost::redis::response;
 using boost::redis::operation;
 using boost::redis::ignore_t;
 using boost::redis::config;
 using boost::redis::connection;
+using boost::redis::resp3::node_view;
 
 // The protobuf type described in example/person.proto
 using tutorial::person;
 
 // Boost.Redis customization points (example/protobuf.hpp)
-namespace tutorial
-{
+namespace tutorial {
 
 // Below I am using a Boost.Redis to indicate a protobuf error, this
 // is ok for an example, users however might want to define their own
@@ -43,17 +45,17 @@ void boost_redis_to_bulk(std::string& to, person const& u)
    if (!u.SerializeToString(&tmp))
       throw boost::system::system_error(boost::redis::error::invalid_data_type);
 
-   boost::redis::resp3::boost_redis_to_bulk(to, tmp);
+   resp3::boost_redis_to_bulk(to, tmp);
 }
 
-void boost_redis_from_bulk(person& u, std::string_view sv, boost::system::error_code& ec)
+void boost_redis_from_bulk(person& u, node_view const& node, boost::system::error_code& ec)
 {
-   std::string const tmp {sv};
+   std::string const tmp{node.value};
    if (!u.ParseFromString(tmp))
       ec = boost::redis::error::invalid_data_type;
 }
 
-} // tutorial
+}  // namespace tutorial
 
 using tutorial::boost_redis_to_bulk;
 using tutorial::boost_redis_from_bulk;
@@ -62,7 +64,7 @@ asio::awaitable<void> co_main(config cfg)
 {
    auto ex = co_await asio::this_coro::executor;
    auto conn = std::make_shared<connection>(ex);
-   conn->async_run(cfg, {}, asio::consign(asio::detached, conn));
+   conn->async_run(cfg, asio::consign(asio::detached, conn));
 
    person p;
    p.set_name("Louis");
@@ -76,13 +78,12 @@ asio::awaitable<void> co_main(config cfg)
    response<ignore_t, person> resp;
 
    // Sends the request and receives the response.
-   co_await conn->async_exec(req, resp, asio::deferred);
+   co_await conn->async_exec(req, resp);
    conn->cancel();
 
-   std::cout
-      << "Name: " << std::get<1>(resp).value().name() << "\n"
-      << "Age: " << std::get<1>(resp).value().id() << "\n"
-      << "Email: " << std::get<1>(resp).value().email() << "\n";
+   std::cout << "Name: " << std::get<1>(resp).value().name() << "\n"
+             << "Age: " << std::get<1>(resp).value().id() << "\n"
+             << "Email: " << std::get<1>(resp).value().email() << "\n";
 }
 
-#endif // defined(BOOST_ASIO_HAS_CO_AWAIT)
+#endif  // defined(BOOST_ASIO_HAS_CO_AWAIT)

example/cpp20_resolve_with_sentinel.cpp

@@ -1,75 +0,0 @@
-/* Copyright (c) 2018-2022 Marcelo Zimbres Silva (mzimbres@gmail.com)
- *
- * Distributed under the Boost Software License, Version 1.0. (See
- * accompanying file LICENSE.txt)
- */
-
-#include <boost/redis/connection.hpp>
-#include <boost/asio/use_awaitable.hpp>
-#include <boost/asio/redirect_error.hpp>
-#include <boost/asio/detached.hpp>
-#include <iostream>
-
-#if defined(BOOST_ASIO_HAS_CO_AWAIT)
-
-namespace asio = boost::asio;
-using endpoints = asio::ip::tcp::resolver::results_type;
-using boost::redis::request;
-using boost::redis::response;
-using boost::redis::ignore_t;
-using boost::redis::config;
-using boost::redis::address;
-using boost::redis::connection;
-
-auto redir(boost::system::error_code& ec)
-   { return asio::redirect_error(asio::use_awaitable, ec); }
-
-// For more info see
-// - https://redis.io/docs/manual/sentinel.
-// - https://redis.io/docs/reference/sentinel-clients.
-auto resolve_master_address(std::vector<address> const& addresses) -> asio::awaitable<address>
-{
-   request req;
-   req.push("SENTINEL", "get-master-addr-by-name", "mymaster");
-   req.push("QUIT");
-
-   auto conn = std::make_shared<connection>(co_await asio::this_coro::executor);
-
-   response<std::optional<std::array<std::string, 2>>, ignore_t> resp;
-   for (auto addr : addresses) {
-      boost::system::error_code ec;
-      config cfg;
-      cfg.addr = addr;
-      // TODO: async_run and async_exec should be lauched in
-      // parallel here so we can wait for async_run completion
-      // before eventually calling it again.
-      conn->async_run(cfg, {}, asio::consign(asio::detached, conn));
-      co_await conn->async_exec(req, resp, redir(ec));
-      conn->cancel();
-      conn->reset_stream();
-      if (!ec && std::get<0>(resp))
-         co_return address{std::get<0>(resp).value().value().at(0), std::get<0>(resp).value().value().at(1)};
-   }
-
-   co_return address{};
-}
-
-auto co_main(config cfg) -> asio::awaitable<void>
-{
-   // A list of sentinel addresses from which only one is responsive.
-   // This simulates sentinels that are down.
-   std::vector<address> const addresses
-   { address{"foo", "26379"}
-   , address{"bar", "26379"}
-   , cfg.addr
-   };
-
-   auto const ep = co_await resolve_master_address(addresses);
-
-   std::clog
-      << "Host: " << ep.host << "\n"
-      << "Port: " << ep.port << "\n"
-      << std::flush;
-}
-
-#endif // defined(BOOST_ASIO_HAS_CO_AWAIT)

example/cpp20_sentinel.cpp

@@ -0,0 +1,60 @@
+//
+// Copyright (c) 2025 Marcelo Zimbres Silva (mzimbres@gmail.com),
+// Ruben Perez Hidalgo (rubenperez038 at gmail dot com)
+//
+// Distributed under the Boost Software License, Version 1.0. (See accompanying
+// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+//
+
+#include <boost/redis/connection.hpp>
+
+#include <boost/asio/co_spawn.hpp>
+#include <boost/asio/consign.hpp>
+#include <boost/asio/detached.hpp>
+
+#include <iostream>
+
+#if defined(BOOST_ASIO_HAS_CO_AWAIT)
+
+namespace asio = boost::asio;
+using boost::redis::request;
+using boost::redis::response;
+using boost::redis::config;
+using boost::redis::connection;
+
+// Called from the main function (see main.cpp)
+auto co_main(config cfg) -> asio::awaitable<void>
+{
+   // Boost.Redis has built-in support for Sentinel deployments.
+   // To enable it, set the fields in config shown here.
+   // sentinel.addresses should contain a list of (hostname, port) pairs
+   // where Sentinels are listening. IPs can also be used.
+   cfg.sentinel.addresses = {
+      {"localhost", "26379"},
+      {"localhost", "26380"},
+      {"localhost", "26381"},
+   };
+
+   // Set master_name to the identifier that you configured
+   // in the "sentinel monitor" statement of your sentinel.conf file
+   cfg.sentinel.master_name = "mymaster";
+
+   // async_run will contact the Sentinels, obtain the master address,
+   // connect to it and keep the connection healthy. If a failover happens,
+   // the address will be resolved again and the new elected master will be contacted.
+   auto conn = std::make_shared<connection>(co_await asio::this_coro::executor);
+   conn->async_run(cfg, asio::consign(asio::detached, conn));
+
+   // You can now use the connection normally, as you would use a connection to a single master.
+   request req;
+   req.push("PING", "Hello world");
+   response<std::string> resp;
+
+   // Execute the request.
+   co_await conn->async_exec(req, resp);
+   conn->cancel();
+
+   std::cout << "PING: " << std::get<0>(resp).value() << std::endl;
+}
+
+#endif  // defined(BOOST_ASIO_HAS_CO_AWAIT)

example/cpp20_streams.cpp

@@ -5,12 +5,13 @@
  */
 
 #include <boost/redis/connection.hpp>
-#include <boost/asio/deferred.hpp>
-#include <boost/asio/co_spawn.hpp>
-#include <boost/asio/detached.hpp>
-#include <boost/asio/consign.hpp>
-#include <boost/asio/signal_set.hpp>
+
 #include <boost/asio/awaitable.hpp>
+#include <boost/asio/co_spawn.hpp>
+#include <boost/asio/consign.hpp>
+#include <boost/asio/detached.hpp>
+#include <boost/asio/signal_set.hpp>
+
 #include <iostream>
 
 #if defined(BOOST_ASIO_HAS_CO_AWAIT)
@@ -26,57 +27,55 @@ using boost::redis::generic_response;
 using boost::redis::operation;
 using boost::redis::request;
 using boost::redis::connection;
-using signal_set = net::deferred_t::as_default_on_t<net::signal_set>;
+using net::signal_set;
 
 auto stream_reader(std::shared_ptr<connection> conn) -> net::awaitable<void>
 {
-    std::string redisStreamKey_;
-    request req;
-    generic_response resp;
+   std::string redisStreamKey_;
+   request req;
+   generic_response resp;
 
-    std::string stream_id{"$"};
-    std::string const field = "myfield";
+   std::string stream_id{"$"};
+   std::string const field = "myfield";
 
-    for (;;) {
-        req.push("XREAD", "BLOCK", "0", "STREAMS", "test-topic", stream_id);
-        co_await conn->async_exec(req, resp, net::deferred);
+   for (;;) {
+      req.push("XREAD", "BLOCK", "0", "STREAMS", "test-topic", stream_id);
+      co_await conn->async_exec(req, resp);
 
-        //std::cout << "Response: ";
-        //for (auto i = 0UL; i < resp->size(); ++i) {
-        //    std::cout << resp->at(i).value << ", ";
-        //}
-        //std::cout << std::endl;
+      //std::cout << "Response: ";
+      //for (auto i = 0UL; i < resp->size(); ++i) {
+      //    std::cout << resp->at(i).value << ", ";
+      //}
+      //std::cout << std::endl;
 
-        // The following approach was taken in order to be able to
-        // deal with the responses, as generated by redis in the case
-        // that there are multiple stream 'records' within a single
-        // generic_response.  The nesting and number of values in
-        // resp.value() are different, depending on the contents
-        // of the stream in redis.  Uncomment the above commented-out
-        // code for examples while running the XADD command.
+      // The following approach was taken in order to be able to
+      // deal with the responses, as generated by redis in the case
+      // that there are multiple stream 'records' within a single
+      // generic_response.  The nesting and number of values in
+      // resp.value() are different, depending on the contents
+      // of the stream in redis.  Uncomment the above commented-out
+      // code for examples while running the XADD command.
 
-        std::size_t item_index = 0;
-        while (item_index < std::size(resp.value())) {
-           auto const& val = resp.value().at(item_index).value;
+      std::size_t item_index = 0;
+      while (item_index < std::size(resp.value())) {
+         auto const& val = resp.value().at(item_index).value;
 
-           if (field.compare(val) == 0) {
-               // We've hit a myfield field.
-               // The streamId is located at item_index - 2
-               // The payload is located at item_index + 1
-               stream_id = resp.value().at(item_index - 2).value;
-               std::cout
-                  << "StreamId: " << stream_id << ", "
-                  << "MyField: " << resp.value().at(item_index + 1).value
-                  << std::endl;
-               ++item_index; // We can increase so we don't read this again
-           }
+         if (field.compare(val) == 0) {
+            // We've hit a myfield field.
+            // The streamId is located at item_index - 2
+            // The payload is located at item_index + 1
+            stream_id = resp.value().at(item_index - 2).value;
+            std::cout << "StreamId: " << stream_id << ", "
+                      << "MyField: " << resp.value().at(item_index + 1).value << std::endl;
+            ++item_index;  // We can increase so we don't read this again
+         }
 
-           ++item_index;
-        }
+         ++item_index;
+      }
 
-        req.clear();
-        resp.value().clear();
-    }
+      req.clear();
+      resp.value().clear();
+   }
 }
 
 // Run this in another terminal:
@@ -89,10 +88,10 @@ auto co_main(config cfg) -> net::awaitable<void>
 
    // Disable health checks.
    cfg.health_check_interval = std::chrono::seconds::zero();
-   conn->async_run(cfg, {}, net::consign(net::detached, conn));
+   conn->async_run(cfg, net::consign(net::detached, conn));
 
    signal_set sig_set(ex, SIGINT, SIGTERM);
    co_await sig_set.async_wait();
    conn->cancel();
 }
-#endif // defined(BOOST_ASIO_HAS_CO_AWAIT)
+#endif  // defined(BOOST_ASIO_HAS_CO_AWAIT)

example/cpp20_subscriber.cpp

@@ -1,19 +1,18 @@
-/* Copyright (c) 2018-2022 Marcelo Zimbres Silva (mzimbres@gmail.com)
+/* Copyright (c) 2018-2025 Marcelo Zimbres Silva (mzimbres@gmail.com)
  *
  * Distributed under the Boost Software License, Version 1.0. (See
  * accompanying file LICENSE.txt)
  */
 
 #include <boost/redis/connection.hpp>
-#include <boost/redis/logger.hpp>
+
+#include <boost/asio/as_tuple.hpp>
 #include <boost/asio/awaitable.hpp>
-#include <boost/asio/use_awaitable.hpp>
-#include <boost/asio/deferred.hpp>
 #include <boost/asio/co_spawn.hpp>
-#include <boost/asio/detached.hpp>
 #include <boost/asio/consign.hpp>
-#include <boost/asio/redirect_error.hpp>
+#include <boost/asio/detached.hpp>
 #include <boost/asio/signal_set.hpp>
+
 #include <iostream>
 
 #if defined(BOOST_ASIO_HAS_CO_AWAIT)
@@ -21,22 +20,18 @@
 namespace asio = boost::asio;
 using namespace std::chrono_literals;
 using boost::redis::request;
-using boost::redis::generic_response;
-using boost::redis::consume_one;
-using boost::redis::logger;
+using boost::redis::generic_flat_response;
 using boost::redis::config;
-using boost::redis::ignore;
-using boost::redis::error;
 using boost::system::error_code;
 using boost::redis::connection;
-using signal_set = asio::deferred_t::as_default_on_t<asio::signal_set>;
+using asio::signal_set;
 
 /* This example will subscribe and read pushes indefinitely.
  *
  * To test send messages with redis-cli
  *
  *    $ redis-cli -3
- *    127.0.0.1:6379> PUBLISH channel some-message
+ *    127.0.0.1:6379> PUBLISH mychannel some-message
  *    (integer) 3
  *    127.0.0.1:6379>
  *
@@ -48,41 +43,41 @@ using signal_set = asio::deferred_t::as_default_on_t<asio::signal_set>;
  */
 
 // Receives server pushes.
-auto
-receiver(std::shared_ptr<connection> conn) -> asio::awaitable<void>
+auto receiver(std::shared_ptr<connection> conn) -> asio::awaitable<void>
 {
-   request req;
-   req.push("SUBSCRIBE", "channel");
-
-   generic_response resp;
+   generic_flat_response resp;
    conn->set_receive_response(resp);
 
-   // Loop while reconnection is enabled
+   // Subscribe to the channel 'mychannel'. You can add any number of channels here.
+   request req;
+   req.subscribe({"mychannel"});
+   co_await conn->async_exec(req);
+
+   // You're now subscribed to 'mychannel'. Pushes sent over this channel will be stored
+   // in resp. If the connection encounters a network error and reconnects to the server,
+   // it will automatically subscribe to 'mychannel' again. This is transparent to the user.
+   // You need to use specialized request::subscribe() function (instead of request::push)
+   // to enable this behavior.
+
+   // Loop to read Redis push messages.
    while (conn->will_reconnect()) {
+      // Wait for pushes
+      auto [ec] = co_await conn->async_receive2(asio::as_tuple);
 
-      // Reconnect to the channels.
-      co_await conn->async_exec(req, ignore, asio::deferred);
-
-      // Loop reading Redis pushs messages.
-      for (error_code ec;;) {
-         // First tries to read any buffered pushes.
-         conn->receive(ec);
-         if (ec == error::sync_receive_push_failed) {
-            ec = {};
-            co_await conn->async_receive(asio::redirect_error(asio::use_awaitable, ec));
-         }
-
-         if (ec)
-            break; // Connection lost, break so we can reconnect to channels.
-
-         std::cout
-            << resp.value().at(1).value
-            << " " << resp.value().at(2).value
-            << " " << resp.value().at(3).value
-            << std::endl;
-
-         consume_one(resp);
+      // Check for errors and cancellations
+      if (ec) {
+         std::cerr << "Error during receive: " << ec << std::endl;
+         break;
       }
+
+      // The response must be consumed without suspending the
+      // coroutine i.e. without the use of async operations.
+      for (auto const& elem : resp.value())
+         std::cout << elem.value << "\n";
+
+      std::cout << std::endl;
+
+      resp.value().clear();
    }
 }
 
@@ -91,7 +86,7 @@ auto co_main(config cfg) -> asio::awaitable<void>
    auto ex = co_await asio::this_coro::executor;
    auto conn = std::make_shared<connection>(ex);
    asio::co_spawn(ex, receiver(conn), asio::detached);
-   conn->async_run(cfg, {}, asio::consign(asio::detached, conn));
+   conn->async_run(cfg, asio::consign(asio::detached, conn));
 
    signal_set sig_set(ex, SIGINT, SIGTERM);
    co_await sig_set.async_wait();
@@ -99,4 +94,4 @@ auto co_main(config cfg) -> asio::awaitable<void>
    conn->cancel();
 }
 
-#endif // defined(BOOST_ASIO_HAS_CO_AWAIT)
+#endif  // defined(BOOST_ASIO_HAS_CO_AWAIT)

example/cpp20_timeouts.cpp

@@ -0,0 +1,49 @@
+/* Copyright (c) 2018-2022 Marcelo Zimbres Silva (mzimbres@gmail.com)
+ *
+ * Distributed under the Boost Software License, Version 1.0. (See
+ * accompanying file LICENSE.txt)
+ */
+
+#include <boost/redis/connection.hpp>
+
+#include <boost/asio/cancel_after.hpp>
+#include <boost/asio/co_spawn.hpp>
+#include <boost/asio/consign.hpp>
+#include <boost/asio/detached.hpp>
+
+#include <iostream>
+
+#if defined(BOOST_ASIO_HAS_CO_AWAIT)
+
+namespace asio = boost::asio;
+using boost::redis::request;
+using boost::redis::response;
+using boost::redis::config;
+using boost::redis::connection;
+using namespace std::chrono_literals;
+
+// Called from the main function (see main.cpp)
+auto co_main(config cfg) -> asio::awaitable<void>
+{
+   auto conn = std::make_shared<connection>(co_await asio::this_coro::executor);
+   conn->async_run(cfg, asio::consign(asio::detached, conn));
+
+   // A request containing only a ping command.
+   request req;
+   req.push("PING", "Hello world");
+
+   // Response where the PONG response will be stored.
+   response<std::string> resp;
+
+   // Executes the request with a timeout. If the server is down,
+   // async_exec will wait until it's back again, so it,
+   // may suspend for a long time.
+   // For this reason, it's good practice to set a timeout to requests with cancel_after.
+   // If the request hasn't completed after 10 seconds, an exception will be thrown.
+   co_await conn->async_exec(req, resp, asio::cancel_after(10s));
+   conn->cancel();
+
+   std::cout << "PING: " << std::get<0>(resp).value() << std::endl;
+}
+
+#endif  // defined(BOOST_ASIO_HAS_CO_AWAIT)

example/cpp20_unix_sockets.cpp

@@ -0,0 +1,60 @@
+//
+// Copyright (c) 2025 Marcelo Zimbres Silva (mzimbres@gmail.com),
+// Ruben Perez Hidalgo (rubenperez038 at gmail dot com)
+//
+// Distributed under the Boost Software License, Version 1.0. (See accompanying
+// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+//
+#include <boost/asio/awaitable.hpp>
+
+#if defined(BOOST_ASIO_HAS_CO_AWAIT)
+
+#include <boost/redis/connection.hpp>
+
+#include <boost/asio/consign.hpp>
+#include <boost/asio/detached.hpp>
+#include <boost/asio/this_coro.hpp>
+
+#include <iostream>
+
+namespace asio = boost::asio;
+using boost::redis::request;
+using boost::redis::response;
+using boost::redis::config;
+using boost::redis::logger;
+using boost::redis::connection;
+
+#ifdef BOOST_ASIO_HAS_LOCAL_SOCKETS
+
+auto co_main(config cfg) -> asio::awaitable<void>
+{
+   // If unix_socket is set to a non-empty string, UNIX domain sockets will be used
+   // instead of TCP. Set this value to the path where your server is listening.
+   // UNIX domain socket connections work in the same way as TCP connections.
+   cfg.unix_socket = "/tmp/redis-socks/redis.sock";
+
+   auto conn = std::make_shared<connection>(co_await asio::this_coro::executor);
+   conn->async_run(cfg, asio::consign(asio::detached, conn));
+
+   request req;
+   req.push("PING");
+
+   response<std::string> resp;
+
+   co_await conn->async_exec(req, resp);
+   conn->cancel();
+
+   std::cout << "Response: " << std::get<0>(resp).value() << std::endl;
+}
+
+#else
+
+auto co_main(config) -> asio::awaitable<void>
+{
+   std::cout << "Sorry, your system does not support UNIX domain sockets\n";
+   co_return;
+}
+
+#endif
+
+#endif

example/main.cpp

@@ -4,11 +4,13 @@
  * accompanying file LICENSE.txt)
  */
 
-#include <boost/redis/connection.hpp>
 #include <boost/redis/config.hpp>
+#include <boost/redis/connection.hpp>
+
 #include <boost/asio/co_spawn.hpp>
-#include <boost/asio/use_awaitable.hpp>
 #include <boost/asio/io_context.hpp>
+#include <boost/asio/use_awaitable.hpp>
+
 #include <iostream>
 
 namespace asio = boost::asio;
@@ -19,7 +21,7 @@ using boost::redis::logger;
 
 extern asio::awaitable<void> co_main(config);
 
-auto main(int argc, char * argv[]) -> int
+auto main(int argc, char* argv[]) -> int
 {
    try {
       config cfg;
@@ -42,7 +44,7 @@ auto main(int argc, char * argv[]) -> int
    }
 }
 
-#else // defined(BOOST_ASIO_HAS_CO_AWAIT)
+#else  // defined(BOOST_ASIO_HAS_CO_AWAIT)
 
 auto main() -> int
 {
@@ -50,4 +52,4 @@ auto main() -> int
    return 0;
 }
 
-#endif // defined(BOOST_ASIO_HAS_CO_AWAIT)
+#endif  // defined(BOOST_ASIO_HAS_CO_AWAIT)

example/sync_connection.hpp

@@ -1,5 +1,5 @@
 
-/* Copyright (c) 2018-2023 Marcelo Zimbres Silva (mzimbres@gmail.com)
+/* Copyright (c) 2018-2024 Marcelo Zimbres Silva (mzimbres@gmail.com)
  *
  * Distributed under the Boost Software License, Version 1.0. (See
  * accompanying file LICENSE.txt)
@@ -7,16 +7,17 @@
 
 #include <boost/redis/connection.hpp>
 #include <boost/redis/request.hpp>
+
 #include <boost/asio/deferred.hpp>
 #include <boost/asio/detached.hpp>
 #include <boost/asio/use_future.hpp>
-#include <thread>
+
 #include <chrono>
+#include <thread>
 
 using namespace std::chrono_literals;
 
-namespace boost::redis
-{
+namespace boost::redis {
 
 class sync_connection {
 public:
@@ -25,33 +26,32 @@ public:
    , conn_{std::make_shared<connection>(ioc_)}
    { }
 
-   ~sync_connection()
-   {
-      thread_.join();
-   }
+   ~sync_connection() { thread_.join(); }
 
    void run(config cfg)
    {
       // Starts a thread that will can io_context::run on which the
       // connection will run.
       thread_ = std::thread{[this, cfg]() {
-         conn_->async_run(cfg, {}, asio::detached);
+         conn_->async_run(cfg, asio::detached);
          ioc_.run();
       }};
    }
 
    void stop()
    {
-      asio::dispatch(ioc_, [this]() { conn_->cancel(); });
+      asio::dispatch(ioc_, [this]() {
+         conn_->cancel();
+      });
    }
 
    template <class Response>
    auto exec(request const& req, Response& resp)
    {
-      asio::dispatch(
-         conn_->get_executor(),
-         asio::deferred([this, &req, &resp]() { return conn_->async_exec(req, resp, asio::deferred); }))
-         (asio::use_future).get();
+      asio::dispatch(conn_->get_executor(), asio::deferred([this, &req, &resp]() {
+                        return conn_->async_exec(req, resp, asio::deferred);
+                     }))(asio::use_future)
+         .get();
    }
 
 private:
@@ -60,4 +60,4 @@ private:
    std::thread thread_;
 };
 
-}
+}  // namespace boost::redis

include/boost/redis.hpp

@@ -1,4 +1,4 @@
-/* Copyright (c) 2018-2023 Marcelo Zimbres Silva (mzimbres@gmail.com)
+/* Copyright (c) 2018-2024 Marcelo Zimbres Silva (mzimbres@gmail.com)
  *
  * Distributed under the Boost Software License, Version 1.0. (See
  * accompanying file LICENSE.txt)
@@ -8,12 +8,12 @@
 #define BOOST_REDIS_HPP
 
 #include <boost/redis/config.hpp>
-#include <boost/redis/error.hpp>
 #include <boost/redis/connection.hpp>
-#include <boost/redis/request.hpp>
-#include <boost/redis/response.hpp>
+#include <boost/redis/error.hpp>
 #include <boost/redis/ignore.hpp>
 #include <boost/redis/logger.hpp>
+#include <boost/redis/request.hpp>
+#include <boost/redis/response.hpp>
 
 /** @defgroup high-level-api Reference
  *
@@ -25,4 +25,4 @@
  *  This page contains the documentation of the Aedis low-level API.
  */
 
-#endif // BOOST_REDIS_HPP
+#endif  // BOOST_REDIS_HPP

include/boost/redis/adapter/adapt.hpp

@@ -1,4 +1,4 @@
-/* Copyright (c) 2018-2023 Marcelo Zimbres Silva (mzimbres@gmail.com)
+/* Copyright (c) 2018-2024 Marcelo Zimbres Silva (mzimbres@gmail.com)
  *
  * Distributed under the Boost Software License, Version 1.0. (See
  * accompanying file LICENSE.txt)
@@ -7,74 +7,40 @@
 #ifndef BOOST_REDIS_ADAPTER_ADAPT_HPP
 #define BOOST_REDIS_ADAPTER_ADAPT_HPP
 
-#include <boost/redis/resp3/node.hpp>
-#include <boost/redis/response.hpp>
-#include <boost/redis/adapter/detail/result_traits.hpp>
 #include <boost/redis/adapter/detail/response_traits.hpp>
-#include <boost/mp11.hpp>
-#include <boost/system.hpp>
+#include <boost/redis/adapter/detail/result_traits.hpp>
+#include <boost/redis/ignore.hpp>
 
-#include <tuple>
-#include <limits>
-#include <string_view>
-#include <variant>
-
-namespace boost::redis::adapter
-{
+namespace boost::redis::adapter {
 
 /** @brief Adapts a type to be used as a response.
  *
  *  The type T must be either
  *
- *  1. a response<T1, T2, T3, ...> or
- *  2. std::vector<node<String>>
+ *  @li a `response<T1, T2, T3, ...>`
+ *  @li `std::vector<node<String>>`
  *
  *  The types T1, T2, etc can be any STL container, any integer type
  *  and `std::string`.
  *
- *  @param t Tuple containing the responses.
+ *  @tparam T The response type.
  */
-template<class T>
+template <class T>
 auto boost_redis_adapt(T& t) noexcept
 {
    return detail::response_traits<T>::adapt(t);
 }
 
-/** @brief Adapts user data to read operations.
- *  @ingroup low-level-api
+/** @brief Adapts a type to be used as the response to an individual command.
  *
- *  STL containers, \c resp3::response and built-in types are supported and
- *  can be used in conjunction with \c std::optional<T>.
- *
- *  Example usage:
- *
- *  @code
- *  std::unordered_map<std::string, std::string> cont;
- *  co_await async_read(socket, buffer, adapt(cont));
- *  @endcode
- * 
- *  For a transaction
- *
- *  @code
- *  sr.push(command::multi);
- *  sr.push(command::ping, ...);
- *  sr.push(command::incr, ...);
- *  sr.push_range(command::rpush, ...);
- *  sr.push(command::lrange, ...);
- *  sr.push(command::incr, ...);
- *  sr.push(command::exec);
- *
- *  co_await async_write(socket, buffer(request));
- *
- *  // Reads the response to a transaction
- *  resp3::response<std::string, int, int, std::vector<std::string>, int> execs;
- *  co_await resp3::async_read(socket, dynamic_buffer(buffer), adapt(execs));
- *  @endcode
+ * It can be used with low-level APIs, like @ref boost::redis::resp3::parser.
  */
-template<class T>
+template <class T>
 auto adapt2(T& t = redis::ignore) noexcept
-   { return detail::result_traits<T>::adapt(t); }
+{
+   return detail::result_traits<T>::adapt(t);
+}
 
-} // boost::redis::adapter
+}  // namespace boost::redis::adapter
 
-#endif // BOOST_REDIS_ADAPTER_ADAPT_HPP
+#endif  // BOOST_REDIS_ADAPTER_ADAPT_HPP

include/boost/redis/adapter/any_adapter.hpp

@@ -0,0 +1,125 @@
+/* Copyright (c) 2018-2025 Marcelo Zimbres Silva (mzimbres@gmail.com)
+ *
+ * Distributed under the Boost Software License, Version 1.0. (See
+ * accompanying file LICENSE.txt)
+ */
+
+#ifndef BOOST_REDIS_ANY_ADAPTER_HPP
+#define BOOST_REDIS_ANY_ADAPTER_HPP
+
+#include <boost/redis/adapter/adapt.hpp>
+#include <boost/redis/resp3/node.hpp>
+
+#include <boost/system/error_code.hpp>
+
+#include <functional>
+#include <type_traits>
+
+namespace boost::redis {
+
+/** @brief A type-erased reference to a response.
+ *
+ *  A type-erased response adapter. It can be executed using @ref connection::async_exec.
+ *  Using this type instead of raw response references enables separate compilation.
+ *
+ *  Given a response object `resp` that can be passed to `async_exec`, the following two
+ *  statements have the same effect:
+ *
+ *  @code
+ *      co_await conn.async_exec(req, resp);
+ *      co_await conn.async_exec(req, any_response(resp));
+ *  @endcode
+ */
+class any_adapter {
+public:
+   /** @brief Parse events that an adapter must support.
+    */
+   enum class parse_event
+   {
+      /// Called before the parser starts processing data
+      init,
+      /// Called for each and every node of RESP3 data
+      node,
+      /// Called when done processing a complete RESP3 message
+      done
+   };
+
+   /// The type erased implementation type.
+   using impl_t = std::function<void(parse_event, resp3::node_view const&, system::error_code&)>;
+
+   template <class T>
+   static auto create_impl(T& resp) -> impl_t;
+
+   /// Contructs from a type erased adaper
+   any_adapter(impl_t fn = [](parse_event, resp3::node_view const&, system::error_code&) { })
+   : impl_{std::move(fn)}
+   { }
+
+   /**
+     * @brief Constructor.
+     * 
+     * Creates a type-erased response adapter from `resp` by calling
+     * `boost_redis_adapt`. `T` must be a valid Redis response type.
+     * Any type passed to @ref connection::async_exec qualifies.
+     *
+     * This object stores a reference to `resp`, which must be kept alive
+     * while `*this` is being used.
+     */
+   template <class T, class = std::enable_if_t<!std::is_same_v<T, any_adapter>>>
+   explicit any_adapter(T& resp)
+   : impl_(create_impl(resp))
+   { }
+
+   /// Calls the implementation with the arguments `impl_(parse_event::init, ...);`
+   void on_init()
+   {
+      system::error_code ec;
+      impl_(parse_event::init, {}, ec);
+   };
+
+   /// Calls the implementation with the arguments `impl_(parse_event::done, ...);`
+   void on_done()
+   {
+      system::error_code ec;
+      impl_(parse_event::done, {}, ec);
+   };
+
+   /// Calls the implementation with the arguments `impl_(parse_event::node, ...);`
+   void on_node(resp3::node_view const& nd, system::error_code& ec)
+   {
+      impl_(parse_event::node, nd, ec);
+   };
+
+private:
+   impl_t impl_;
+};
+
+namespace detail {
+
+template <class Adapter>
+any_adapter::impl_t make_any_adapter_impl(Adapter&& value)
+{
+   return [adapter = std::move(value)](
+             any_adapter::parse_event ev,
+             resp3::node_view const& nd,
+             system::error_code& ec) mutable {
+      switch (ev) {
+         case any_adapter::parse_event::init: adapter.on_init(); break;
+         case any_adapter::parse_event::node: adapter.on_node(nd, ec); break;
+         case any_adapter::parse_event::done: adapter.on_done(); break;
+      }
+   };
+}
+
+}  // namespace detail
+
+}  // namespace boost::redis
+
+template <class T>
+auto boost::redis::any_adapter::create_impl(T& resp) -> impl_t
+{
+   using adapter::boost_redis_adapt;
+   return detail::make_any_adapter_impl(boost_redis_adapt(resp));
+}
+
+#endif

include/boost/redis/adapter/detail/adapters.hpp

@@ -1,4 +1,4 @@
-/* Copyright (c) 2018-2023 Marcelo Zimbres Silva (mzimbres@gmail.com)
+/* Copyright (c) 2018-2025 Marcelo Zimbres Silva (mzimbres@gmail.com)
  *
  * Distributed under the Boost Software License, Version 1.0. (See
  * accompanying file LICENSE.txt)
@@ -7,80 +7,135 @@
 #ifndef BOOST_REDIS_ADAPTER_ADAPTERS_HPP
 #define BOOST_REDIS_ADAPTER_ADAPTERS_HPP
 
-#include <boost/redis/error.hpp>
-#include <boost/redis/resp3/type.hpp>
-#include <boost/redis/resp3/serialization.hpp>
-#include <boost/redis/resp3/node.hpp>
 #include <boost/redis/adapter/result.hpp>
+#include <boost/redis/error.hpp>
+#include <boost/redis/resp3/flat_tree.hpp>
+#include <boost/redis/resp3/node.hpp>
+#include <boost/redis/resp3/serialization.hpp>
+#include <boost/redis/resp3/type.hpp>
+#include <boost/redis/response.hpp>
+
 #include <boost/assert.hpp>
 
-#include <set>
-#include <optional>
-#include <unordered_set>
-#include <forward_list>
-#include <system_error>
-#include <map>
-#include <unordered_map>
-#include <list>
-#include <deque>
-#include <vector>
 #include <array>
-#include <string_view>
 #include <charconv>
+#include <deque>
+#include <forward_list>
+#include <list>
+#include <map>
+#include <optional>
+#include <set>
+#include <string_view>
+#include <system_error>
+#include <type_traits>
+#include <unordered_map>
+#include <unordered_set>
+#include <vector>
 
 // See https://stackoverflow.com/a/31658120/1077832
-#include<ciso646>
 #ifdef _LIBCPP_VERSION
 #else
 #include <cstdlib>
 #endif
 
-namespace boost::redis::adapter::detail
-{
+namespace boost::redis::adapter::detail {
 
-// Serialization.
+// Exclude bools, char and charXY_t types
+template <class T> struct is_integral_number : std::is_integral<T> { };
+template <> struct is_integral_number<bool> : std::false_type { };
+template <> struct is_integral_number<char> : std::false_type { };
+template <> struct is_integral_number<char16_t> : std::false_type { };
+template <> struct is_integral_number<char32_t> : std::false_type { };
+template <> struct is_integral_number<wchar_t> : std::false_type { };
+#ifdef __cpp_char8_t
+template <> struct is_integral_number<char8_t> : std::false_type { };
+#endif
+
+template <class T, bool = is_integral_number<T>::value>
+struct converter;
 
 template <class T>
-auto boost_redis_from_bulk(T& i, std::string_view sv, system::error_code& ec) -> typename std::enable_if<std::is_integral<T>::value, void>::type
-{
-   auto const res = std::from_chars(sv.data(), sv.data() + std::size(sv), i);
-   if (res.ec != std::errc())
-      ec = redis::error::not_a_number;
-}
+struct converter<T, true> {
+   template <class String>
+   static void apply(T& i, resp3::basic_node<String> const& node, system::error_code& ec)
+   {
+      auto const res = std::from_chars(node.value.data(), node.value.data() + node.value.size(), i);
+      if (res.ec != std::errc())
+         ec = redis::error::not_a_number;
+   }
+};
 
-inline
-void boost_redis_from_bulk(bool& t, std::string_view sv, system::error_code&)
-{
-   t = *sv.data() == 't';
-}
+template <>
+struct converter<bool, false> {
+   template <class String>
+   static void apply(bool& t, resp3::basic_node<String> const& node, system::error_code&)
+   {
+      t = *node.value.data() == 't';
+   }
+};
 
-inline
-void boost_redis_from_bulk(double& d, std::string_view sv, system::error_code& ec)
-{
+template <>
+struct converter<double, false> {
+   template <class String>
+   static void apply(double& d, resp3::basic_node<String> const& node, system::error_code& ec)
+   {
 #ifdef _LIBCPP_VERSION
-   // The string in sv is not null terminated and we also don't know
-   // if there is enough space at the end for a null char. The easiest
-   // thing to do is to create a temporary.
-   std::string const tmp{sv.data(), sv.data() + std::size(sv)};
-   char* end{};
-   d = std::strtod(tmp.data(), &end);
-   if (d == HUGE_VAL || d == 0)
-      ec = redis::error::not_a_double;
+      // The string in node.value is not null terminated and we also
+      // don't know if there is enough space at the end for a null
+      // char. The easiest thing to do is to create a temporary.
+      std::string const tmp{node.value.data(), node.value.data() + node.value.size()};
+      char* end{};
+      d = std::strtod(tmp.data(), &end);
+      if (d == HUGE_VAL || d == 0)
+         ec = redis::error::not_a_double;
 #else
-   auto const res = std::from_chars(sv.data(), sv.data() + std::size(sv), d);
-   if (res.ec != std::errc())
-      ec = redis::error::not_a_double;
-#endif // _LIBCPP_VERSION
-}
+      auto const res = std::from_chars(node.value.data(), node.value.data() + node.value.size(), d);
+      if (res.ec != std::errc())
+         ec = redis::error::not_a_double;
+#endif  // _LIBCPP_VERSION
+   }
+};
 
 template <class CharT, class Traits, class Allocator>
-void
-boost_redis_from_bulk(
-   std::basic_string<CharT, Traits, Allocator>& s,
-   std::string_view sv,
-   system::error_code&)
+struct converter<std::basic_string<CharT, Traits, Allocator>, false> {
+   template <class String>
+   static void apply(
+      std::basic_string<CharT, Traits, Allocator>& s,
+      resp3::basic_node<String> const& node,
+      system::error_code&)
+   {
+      s.append(node.value.data(), node.value.size());
+   }
+};
+
+template <class T>
+struct from_bulk_impl {
+   template <class String>
+   static void apply(T& t, resp3::basic_node<String> const& node, system::error_code& ec)
+   {
+      converter<T>::apply(t, node, ec);
+   }
+};
+
+template <class T>
+struct from_bulk_impl<std::optional<T>> {
+   template <class String>
+   static void apply(
+      std::optional<T>& op,
+      resp3::basic_node<String> const& node,
+      system::error_code& ec)
+   {
+      if (node.data_type != resp3::type::null) {
+         op.emplace(T{});
+         converter<T>::apply(op.value(), node, ec);
+      }
+   }
+};
+
+template <class T, class String>
+void boost_redis_from_bulk(T& t, resp3::basic_node<String> const& node, system::error_code& ec)
 {
-  s.append(sv.data(), sv.size());
+   from_bulk_impl<T>::apply(t, node, ec);
 }
 
 //================================================
@@ -91,38 +146,155 @@ private:
    Result* result_;
 
 public:
-   explicit general_aggregate(Result* c = nullptr): result_(c) {}
+   explicit general_aggregate(Result* c = nullptr)
+   : result_(c)
+   { }
+
+   void on_init() { }
+   void on_done() { }
+
    template <class String>
-   void operator()(resp3::basic_node<String> const& nd, system::error_code&)
+   void on_node(resp3::basic_node<String> const& nd, system::error_code&)
    {
       BOOST_ASSERT_MSG(!!result_, "Unexpected null pointer");
       switch (nd.data_type) {
          case resp3::type::blob_error:
          case resp3::type::simple_error:
-            *result_ = error{nd.data_type, std::string{std::cbegin(nd.value), std::cend(nd.value)}};
+            *result_ = error{
+               nd.data_type,
+               std::string{std::cbegin(nd.value), std::cend(nd.value)}
+            };
             break;
          default:
-            result_->value().push_back({nd.data_type, nd.aggregate_size, nd.depth, std::string{std::cbegin(nd.value), std::cend(nd.value)}});
+            if (result_->has_value()) {
+               (**result_).push_back({
+                  nd.data_type,
+                  nd.aggregate_size,
+                  nd.depth,
+                  std::string{std::cbegin(nd.value), std::cend(nd.value)}
+               });
+            }
       }
    }
 };
 
+template <>
+class general_aggregate<resp3::tree> {
+private:
+   resp3::tree* tree_ = nullptr;
+
+public:
+   explicit general_aggregate(resp3::tree* c = nullptr)
+   : tree_(c)
+   { }
+
+   void on_init() { }
+   void on_done() { }
+
+   template <class String>
+   void on_node(resp3::basic_node<String> const& nd, system::error_code&)
+   {
+      BOOST_ASSERT_MSG(!!tree_, "Unexpected null pointer");
+
+      resp3::node tmp;
+      tmp.data_type = nd.data_type;
+      tmp.aggregate_size = nd.aggregate_size;
+      tmp.depth = nd.depth;
+      tmp.value = std::string{std::cbegin(nd.value), std::cend(nd.value)};
+
+      tree_->push_back(std::move(tmp));
+   }
+};
+
+template <>
+class general_aggregate<generic_flat_response> {
+private:
+   generic_flat_response* tree_ = nullptr;
+
+public:
+   explicit general_aggregate(generic_flat_response* c = nullptr)
+   : tree_(c)
+   { }
+
+   void on_init()
+   {
+      if (tree_->has_value()) {
+         tree_->value().notify_init();
+      }
+   }
+   void on_done()
+   {
+      BOOST_ASSERT_MSG(!!tree_, "Unexpected null pointer");
+      if (tree_->has_value()) {
+         tree_->value().notify_done();
+      }
+   }
+
+   template <class String>
+   void on_node(resp3::basic_node<String> const& nd, system::error_code&)
+   {
+      BOOST_ASSERT_MSG(!!tree_, "Unexpected null pointer");
+      switch (nd.data_type) {
+         case resp3::type::blob_error:
+         case resp3::type::simple_error:
+            *tree_ = error{
+               nd.data_type,
+               std::string{std::cbegin(nd.value), std::cend(nd.value)}
+            };
+            break;
+         default:
+            if (tree_->has_value()) {
+               (**tree_).push(nd);
+            }
+      }
+   }
+};
+
+template <>
+class general_aggregate<resp3::flat_tree> {
+private:
+   resp3::flat_tree* tree_ = nullptr;
+
+public:
+   explicit general_aggregate(resp3::flat_tree* c = nullptr)
+   : tree_(c)
+   { }
+
+   void on_init() { tree_->notify_init(); }
+   void on_done() { tree_->notify_done(); }
+
+   template <class String>
+   void on_node(resp3::basic_node<String> const& nd, system::error_code&)
+   {
+      BOOST_ASSERT_MSG(!!tree_, "Unexpected null pointer");
+      tree_->push(nd);
+   }
+};
+
 template <class Node>
 class general_simple {
 private:
    Node* result_;
 
 public:
-   explicit general_simple(Node* t = nullptr) : result_(t) {}
+   explicit general_simple(Node* t = nullptr)
+   : result_(t)
+   { }
+
+   void on_init() { }
+   void on_done() { }
 
    template <class String>
-   void operator()(resp3::basic_node<String> const& nd, system::error_code&)
+   void on_node(resp3::basic_node<String> const& nd, system::error_code&)
    {
       BOOST_ASSERT_MSG(!!result_, "Unexpected null pointer");
       switch (nd.data_type) {
          case resp3::type::blob_error:
          case resp3::type::simple_error:
-            *result_ = error{nd.data_type, std::string{std::cbegin(nd.value), std::cend(nd.value)}};
+            *result_ = error{
+               nd.data_type,
+               std::string{std::cbegin(nd.value), std::cend(nd.value)}
+            };
             break;
          default:
             result_->value().data_type = nd.data_type;
@@ -136,17 +308,20 @@ public:
 template <class Result>
 class simple_impl {
 public:
-   void on_value_available(Result&) {}
+   void on_value_available(Result&) { }
+
+   void on_init() { }
+   void on_done() { }
 
    template <class String>
-   void operator()(Result& result, resp3::basic_node<String> const& n, system::error_code& ec)
+   void on_node(Result& result, resp3::basic_node<String> const& node, system::error_code& ec)
    {
-      if (is_aggregate(n.data_type)) {
+      if (is_aggregate(node.data_type)) {
          ec = redis::error::expects_resp3_simple_type;
          return;
       }
 
-      boost_redis_from_bulk(result, n.value, ec);
+      boost_redis_from_bulk(result, node, ec);
    }
 };
 
@@ -156,11 +331,13 @@ private:
    typename Result::iterator hint_;
 
 public:
-   void on_value_available(Result& result)
-      { hint_ = std::end(result); }
+   void on_value_available(Result& result) { hint_ = std::end(result); }
+
+   void on_init() { }
+   void on_done() { }
 
    template <class String>
-   void operator()(Result& result, resp3::basic_node<String> const& nd, system::error_code& ec)
+   void on_node(Result& result, resp3::basic_node<String> const& nd, system::error_code& ec)
    {
       if (is_aggregate(nd.data_type)) {
          if (nd.data_type != resp3::type::set)
@@ -171,12 +348,12 @@ public:
       BOOST_ASSERT(nd.aggregate_size == 1);
 
       if (nd.depth < 1) {
-	 ec = redis::error::expects_resp3_set;
-	 return;
+         ec = redis::error::expects_resp3_set;
+         return;
       }
 
       typename Result::key_type obj;
-      boost_redis_from_bulk(obj, nd.value, ec);
+      boost_redis_from_bulk(obj, nd, ec);
       hint_ = result.insert(hint_, std::move(obj));
    }
 };
@@ -188,32 +365,34 @@ private:
    bool on_key_ = true;
 
 public:
-   void on_value_available(Result& result)
-      { current_ = std::end(result); }
+   void on_value_available(Result& result) { current_ = std::end(result); }
+
+   void on_init() { }
+   void on_done() { }
 
    template <class String>
-   void operator()(Result& result, resp3::basic_node<String> const& nd, system::error_code& ec)
+   void on_node(Result& result, resp3::basic_node<String> const& nd, system::error_code& ec)
    {
       if (is_aggregate(nd.data_type)) {
          if (element_multiplicity(nd.data_type) != 2)
-           ec = redis::error::expects_resp3_map;
+            ec = redis::error::expects_resp3_map;
          return;
       }
 
       BOOST_ASSERT(nd.aggregate_size == 1);
 
       if (nd.depth < 1) {
-	 ec = redis::error::expects_resp3_map;
-	 return;
+         ec = redis::error::expects_resp3_map;
+         return;
       }
 
       if (on_key_) {
          typename Result::key_type obj;
-         boost_redis_from_bulk(obj, nd.value, ec);
+         boost_redis_from_bulk(obj, nd, ec);
          current_ = result.insert(current_, {std::move(obj), {}});
       } else {
          typename Result::mapped_type obj;
-         boost_redis_from_bulk(obj, nd.value, ec);
+         boost_redis_from_bulk(obj, nd, ec);
          current_->second = std::move(obj);
       }
 
@@ -224,17 +403,20 @@ public:
 template <class Result>
 class vector_impl {
 public:
-   void on_value_available(Result& ) { }
+   void on_value_available(Result&) { }
+
+   void on_init() { }
+   void on_done() { }
 
    template <class String>
-   void operator()(Result& result, resp3::basic_node<String> const& nd, system::error_code& ec)
+   void on_node(Result& result, resp3::basic_node<String> const& nd, system::error_code& ec)
    {
       if (is_aggregate(nd.data_type)) {
          auto const m = element_multiplicity(nd.data_type);
          result.reserve(result.size() + m * nd.aggregate_size);
       } else {
          result.push_back({});
-         boost_redis_from_bulk(result.back(), nd.value, ec);
+         boost_redis_from_bulk(result.back(), nd, ec);
       }
    }
 };
@@ -245,13 +427,16 @@ private:
    int i_ = -1;
 
 public:
-   void on_value_available(Result& ) { }
+   void on_value_available(Result&) { }
+
+   void on_init() { }
+   void on_done() { }
 
    template <class String>
-   void operator()(Result& result, resp3::basic_node<String> const& nd, system::error_code& ec)
+   void on_node(Result& result, resp3::basic_node<String> const& nd, system::error_code& ec)
    {
       if (is_aggregate(nd.data_type)) {
-	 if (i_ != -1) {
+         if (i_ != -1) {
             ec = redis::error::nested_aggregate_not_supported;
             return;
          }
@@ -267,7 +452,7 @@ public:
          }
 
          BOOST_ASSERT(nd.aggregate_size == 1);
-         boost_redis_from_bulk(result.at(i_), nd.value, ec);
+         boost_redis_from_bulk(result.at(i_), nd, ec);
       }
 
       ++i_;
@@ -276,21 +461,23 @@ public:
 
 template <class Result>
 struct list_impl {
+   void on_value_available(Result&) { }
 
-   void on_value_available(Result& ) { }
+   void on_init() { }
+   void on_done() { }
 
    template <class String>
-   void operator()(Result& result, resp3::basic_node<String> const& nd, system::error_code& ec)
+   void on_node(Result& result, resp3::basic_node<String> const& nd, system::error_code& ec)
    {
       if (!is_aggregate(nd.data_type)) {
-        BOOST_ASSERT(nd.aggregate_size == 1);
-        if (nd.depth < 1) {
-           ec = redis::error::expects_resp3_aggregate;
-           return;
-        }
+         BOOST_ASSERT(nd.aggregate_size == 1);
+         if (nd.depth < 1) {
+            ec = redis::error::expects_resp3_aggregate;
+            return;
+         }
 
-        result.push_back({});
-        boost_redis_from_bulk(result.back(), nd.value, ec);
+         result.push_back({});
+         boost_redis_from_bulk(result.back(), nd, ec);
       }
    }
 };
@@ -298,56 +485,84 @@ struct list_impl {
 //---------------------------------------------------
 
 template <class T>
-struct impl_map { using type = simple_impl<T>; };
+struct impl_map {
+   using type = simple_impl<T>;
+};
 
 template <class Key, class Compare, class Allocator>
-struct impl_map<std::set<Key, Compare, Allocator>> { using type = set_impl<std::set<Key, Compare, Allocator>>; };
+struct impl_map<std::set<Key, Compare, Allocator>> {
+   using type = set_impl<std::set<Key, Compare, Allocator>>;
+};
 
 template <class Key, class Compare, class Allocator>
-struct impl_map<std::multiset<Key, Compare, Allocator>> { using type = set_impl<std::multiset<Key, Compare, Allocator>>; };
+struct impl_map<std::multiset<Key, Compare, Allocator>> {
+   using type = set_impl<std::multiset<Key, Compare, Allocator>>;
+};
 
 template <class Key, class Hash, class KeyEqual, class Allocator>
-struct impl_map<std::unordered_set<Key, Hash, KeyEqual, Allocator>> { using type = set_impl<std::unordered_set<Key, Hash, KeyEqual, Allocator>>; };
+struct impl_map<std::unordered_set<Key, Hash, KeyEqual, Allocator>> {
+   using type = set_impl<std::unordered_set<Key, Hash, KeyEqual, Allocator>>;
+};
 
 template <class Key, class Hash, class KeyEqual, class Allocator>
-struct impl_map<std::unordered_multiset<Key, Hash, KeyEqual, Allocator>> { using type = set_impl<std::unordered_multiset<Key, Hash, KeyEqual, Allocator>>; };
+struct impl_map<std::unordered_multiset<Key, Hash, KeyEqual, Allocator>> {
+   using type = set_impl<std::unordered_multiset<Key, Hash, KeyEqual, Allocator>>;
+};
 
 template <class Key, class T, class Compare, class Allocator>
-struct impl_map<std::map<Key, T, Compare, Allocator>> { using type = map_impl<std::map<Key, T, Compare, Allocator>>; };
+struct impl_map<std::map<Key, T, Compare, Allocator>> {
+   using type = map_impl<std::map<Key, T, Compare, Allocator>>;
+};
 
 template <class Key, class T, class Compare, class Allocator>
-struct impl_map<std::multimap<Key, T, Compare, Allocator>> { using type = map_impl<std::multimap<Key, T, Compare, Allocator>>; };
+struct impl_map<std::multimap<Key, T, Compare, Allocator>> {
+   using type = map_impl<std::multimap<Key, T, Compare, Allocator>>;
+};
 
 template <class Key, class Hash, class KeyEqual, class Allocator>
-struct impl_map<std::unordered_map<Key, Hash, KeyEqual, Allocator>> { using type = map_impl<std::unordered_map<Key, Hash, KeyEqual, Allocator>>; };
+struct impl_map<std::unordered_map<Key, Hash, KeyEqual, Allocator>> {
+   using type = map_impl<std::unordered_map<Key, Hash, KeyEqual, Allocator>>;
+};
 
 template <class Key, class Hash, class KeyEqual, class Allocator>
-struct impl_map<std::unordered_multimap<Key, Hash, KeyEqual, Allocator>> { using type = map_impl<std::unordered_multimap<Key, Hash, KeyEqual, Allocator>>; };
+struct impl_map<std::unordered_multimap<Key, Hash, KeyEqual, Allocator>> {
+   using type = map_impl<std::unordered_multimap<Key, Hash, KeyEqual, Allocator>>;
+};
 
 template <class T, class Allocator>
-struct impl_map<std::vector<T, Allocator>> { using type = vector_impl<std::vector<T, Allocator>>; };
+struct impl_map<std::vector<T, Allocator>> {
+   using type = vector_impl<std::vector<T, Allocator>>;
+};
 
 template <class T, std::size_t N>
-struct impl_map<std::array<T, N>> { using type = array_impl<std::array<T, N>>; };
+struct impl_map<std::array<T, N>> {
+   using type = array_impl<std::array<T, N>>;
+};
 
 template <class T, class Allocator>
-struct impl_map<std::list<T, Allocator>> { using type = list_impl<std::list<T, Allocator>>; };
+struct impl_map<std::list<T, Allocator>> {
+   using type = list_impl<std::list<T, Allocator>>;
+};
 
 template <class T, class Allocator>
-struct impl_map<std::deque<T, Allocator>> { using type = list_impl<std::deque<T, Allocator>>; };
+struct impl_map<std::deque<T, Allocator>> {
+   using type = list_impl<std::deque<T, Allocator>>;
+};
 
 //---------------------------------------------------
 
 template <class>
 class wrapper;
 
-template <class Result>
-class wrapper<result<Result>> {
+template <class T>
+class wrapper<result<T>> {
 public:
-   using response_type = result<Result>;
+   using response_type = result<T>;
+
 private:
    response_type* result_;
-   typename impl_map<Result>::type impl_;
+   typename impl_map<T>::type impl_;
+   bool called_once_ = false;
 
    template <class String>
    bool set_if_resp3_error(resp3::basic_node<String> const& nd) noexcept
@@ -356,35 +571,41 @@ private:
          case resp3::type::null:
          case resp3::type::simple_error:
          case resp3::type::blob_error:
-            *result_ = error{nd.data_type, {std::cbegin(nd.value), std::cend(nd.value)}};
+            *result_ = error{
+               nd.data_type,
+               {std::cbegin(nd.value), std::cend(nd.value)}
+            };
             return true;
-         default:
-            return false;
+         default: return false;
       }
    }
 
 public:
-   explicit wrapper(response_type* t = nullptr) : result_(t)
+   explicit wrapper(response_type* t = nullptr)
+   : result_(t)
    {
       if (result_) {
-         result_->value() = Result{};
+         result_->value() = T{};
          impl_.on_value_available(result_->value());
       }
    }
 
+   void on_init() { impl_.on_init(); }
+   void on_done() { impl_.on_done(); }
+
    template <class String>
-   void operator()(resp3::basic_node<String> const& nd, system::error_code& ec)
+   void on_node(resp3::basic_node<String> const& nd, system::error_code& ec)
    {
       BOOST_ASSERT_MSG(!!result_, "Unexpected null pointer");
 
       if (result_->has_error())
          return;
 
-      if (set_if_resp3_error(nd))
+      if (!std::exchange(called_once_, true) && set_if_resp3_error(nd))
          return;
 
       BOOST_ASSERT(result_);
-      impl_(result_->value(), nd, ec);
+      impl_.on_node(result_->value(), nd, ec);
    }
 };
 
@@ -396,6 +617,7 @@ public:
 private:
    response_type* result_;
    typename impl_map<T>::type impl_{};
+   bool called_once_ = false;
 
    template <class String>
    bool set_if_resp3_error(resp3::basic_node<String> const& nd) noexcept
@@ -403,21 +625,25 @@ private:
       switch (nd.data_type) {
          case resp3::type::blob_error:
          case resp3::type::simple_error:
-            *result_ = error{nd.data_type, {std::cbegin(nd.value), std::cend(nd.value)}};
+            *result_ = error{
+               nd.data_type,
+               {std::cbegin(nd.value), std::cend(nd.value)}
+            };
             return true;
-         default:
-            return false;
+         default: return false;
       }
    }
 
 public:
-   explicit wrapper(response_type* o = nullptr) : result_(o) {}
+   explicit wrapper(response_type* o = nullptr)
+   : result_(o)
+   { }
+
+   void on_init() { impl_.on_init(); }
+   void on_done() { impl_.on_done(); }
 
    template <class String>
-   void
-   operator()(
-      resp3::basic_node<String> const& nd,
-      system::error_code& ec)
+   void on_node(resp3::basic_node<String> const& nd, system::error_code& ec)
    {
       BOOST_ASSERT_MSG(!!result_, "Unexpected null pointer");
 
@@ -427,18 +653,18 @@ public:
       if (set_if_resp3_error(nd))
          return;
 
-      if (nd.data_type == resp3::type::null)
+      if (!std::exchange(called_once_, true) && nd.data_type == resp3::type::null)
          return;
 
       if (!result_->value().has_value()) {
-        result_->value() = T{};
-        impl_.on_value_available(result_->value().value());
+         result_->value() = T{};
+         impl_.on_value_available(result_->value().value());
       }
 
-      impl_(result_->value().value(), nd, ec);
+      impl_.on_node(result_->value().value(), nd, ec);
    }
 };
 
-} // boost::redis::adapter::detail
+}  // namespace boost::redis::adapter::detail
 
-#endif // BOOST_REDIS_ADAPTER_ADAPTERS_HPP
+#endif  // BOOST_REDIS_ADAPTER_ADAPTERS_HPP

include/boost/redis/adapter/detail/response_traits.hpp

@@ -1,4 +1,4 @@
-/* Copyright (c) 2018-2023 Marcelo Zimbres Silva (mzimbres@gmail.com)
+/* Copyright (c) 2018-2025 Marcelo Zimbres Silva (mzimbres@gmail.com)
  *
  * Distributed under the Boost Software License, Version 1.0. (See
  * accompanying file LICENSE.txt)
@@ -7,37 +7,20 @@
 #ifndef BOOST_REDIS_ADAPTER_DETAIL_RESPONSE_TRAITS_HPP
 #define BOOST_REDIS_ADAPTER_DETAIL_RESPONSE_TRAITS_HPP
 
+#include <boost/redis/adapter/detail/result_traits.hpp>
+#include <boost/redis/ignore.hpp>
 #include <boost/redis/resp3/node.hpp>
 #include <boost/redis/response.hpp>
-#include <boost/redis/adapter/detail/result_traits.hpp>
+
 #include <boost/mp11.hpp>
 #include <boost/system.hpp>
 
-#include <tuple>
 #include <limits>
 #include <string_view>
+#include <tuple>
 #include <variant>
 
-namespace boost::redis::adapter::detail
-{
-
-class ignore_adapter {
-public:
-   template <class String>
-   void operator()(std::size_t, resp3::basic_node<String> const& nd, system::error_code& ec)
-   {
-      switch (nd.data_type) {
-         case resp3::type::simple_error: ec = redis::error::resp3_simple_error; break;
-         case resp3::type::blob_error: ec = redis::error::resp3_blob_error; break;
-         case resp3::type::null: ec = redis::error::resp3_null; break;
-         default:;
-      }
-   }
-
-   [[nodiscard]]
-   auto get_supported_response_size() const noexcept
-      { return static_cast<std::size_t>(-1);}
-};
+namespace boost::redis::adapter::detail {
 
 template <class Response>
 class static_adapter {
@@ -48,47 +31,44 @@ private:
    using adapters_array_type = std::array<variant_type, size>;
 
    adapters_array_type adapters_;
+   std::size_t i_ = 0;
 
 public:
-   explicit static_adapter(Response& r)
-   {
-      assigner<size - 1>::assign(adapters_, r);
-   }
+   explicit static_adapter(Response& r) { assigner<size - 1>::assign(adapters_, r); }
 
-   [[nodiscard]]
-   auto get_supported_response_size() const noexcept
-      { return size;}
-
-   template <class String>
-   void operator()(std::size_t i, resp3::basic_node<String> const& nd, system::error_code& ec)
+   void on_init()
    {
       using std::visit;
-      // I am usure whether this should be an error or an assertion.
-      BOOST_ASSERT(i < adapters_.size());
-      visit([&](auto& arg){arg(nd, ec);}, adapters_.at(i));
+      visit(
+         [&](auto& arg) {
+            arg.on_init();
+         },
+         adapters_.at(i_));
    }
-};
 
-template <class Vector>
-class vector_adapter {
-private:
-   using adapter_type = typename result_traits<Vector>::adapter_type;
-   adapter_type adapter_;
-
-public:
-   explicit vector_adapter(Vector& v)
-   : adapter_{internal_adapt(v)}
-   { }
-
-   [[nodiscard]]
-   auto
-   get_supported_response_size() const noexcept
-      { return static_cast<std::size_t>(-1);}
+   void on_done()
+   {
+      using std::visit;
+      visit(
+         [&](auto& arg) {
+            arg.on_done();
+         },
+         adapters_.at(i_));
+      i_ += 1;
+   }
 
    template <class String>
-   void operator()(std::size_t, resp3::basic_node<String> const& nd, system::error_code& ec)
+   void on_node(resp3::basic_node<String> const& nd, system::error_code& ec)
    {
-      adapter_(nd, ec);
+      using std::visit;
+
+      // I am usure whether this should be an error or an assertion.
+      BOOST_ASSERT(i_ < adapters_.size());
+      visit(
+         [&](auto& arg) {
+            arg.on_node(nd, ec);
+         },
+         adapters_.at(i_));
    }
 };
 
@@ -98,62 +78,59 @@ struct response_traits;
 template <>
 struct response_traits<ignore_t> {
    using response_type = ignore_t;
-   using adapter_type = detail::ignore_adapter;
+   using adapter_type = ignore;
 
-   static auto adapt(response_type&) noexcept
-      { return detail::ignore_adapter{}; }
+   static auto adapt(response_type&) noexcept { return ignore{}; }
 };
 
 template <>
 struct response_traits<result<ignore_t>> {
    using response_type = result<ignore_t>;
-   using adapter_type = detail::ignore_adapter;
+   using adapter_type = ignore;
 
-   static auto adapt(response_type&) noexcept
-      { return detail::ignore_adapter{}; }
+   static auto adapt(response_type&) noexcept { return ignore{}; }
 };
 
 template <class String, class Allocator>
-struct response_traits<result<std::vector<resp3::basic_node<String>, Allocator>>> {
-   using response_type = result<std::vector<resp3::basic_node<String>, Allocator>>;
-   using adapter_type = vector_adapter<response_type>;
+struct response_traits<result<resp3::basic_tree<String, Allocator>>> {
+   using response_type = result<resp3::basic_tree<String, Allocator>>;
+   using adapter_type = general_aggregate<response_type>;
 
-   static auto adapt(response_type& v) noexcept
-      { return adapter_type{v}; }
+   static auto adapt(response_type& v) noexcept { return adapter_type{&v}; }
 };
 
-template <class ...Ts>
+template <class String>
+struct response_traits<resp3::basic_tree<String>> {
+   using response_type = resp3::basic_tree<String>;
+   using adapter_type = general_aggregate<response_type>;
+
+   static auto adapt(response_type& v) noexcept { return adapter_type{&v}; }
+};
+
+template <>
+struct response_traits<resp3::flat_tree> {
+   using response_type = resp3::flat_tree;
+   using adapter_type = general_aggregate<response_type>;
+
+   static auto adapt(response_type& v) noexcept { return adapter_type{&v}; }
+};
+
+template <>
+struct response_traits<generic_flat_response> {
+   using response_type = generic_flat_response;
+   using adapter_type = general_aggregate<response_type>;
+
+   static auto adapt(response_type& v) noexcept { return adapter_type{&v}; }
+};
+
+template <class... Ts>
 struct response_traits<response<Ts...>> {
    using response_type = response<Ts...>;
    using adapter_type = static_adapter<response_type>;
 
-   static auto adapt(response_type& r) noexcept
-      { return adapter_type{r}; }
+   static auto adapt(response_type& r) noexcept { return adapter_type{r}; }
 };
 
-template <class Adapter>
-class wrapper {
-public:
-   explicit wrapper(Adapter adapter) : adapter_{adapter} {}
+}  // namespace boost::redis::adapter::detail
 
-   template <class String>
-   void operator()(resp3::basic_node<String> const& nd, system::error_code& ec)
-      { return adapter_(0, nd, ec); }
-
-   [[nodiscard]]
-   auto get_supported_response_size() const noexcept
-      { return adapter_.get_supported_response_size();}
-
-private:
-   Adapter adapter_;
-};
-
-template <class Adapter>
-auto make_adapter_wrapper(Adapter adapter)
-{
-   return wrapper{adapter};
-}
-
-} // boost::redis::adapter::detail
-
-#endif // BOOST_REDIS_ADAPTER_DETAIL_RESPONSE_TRAITS_HPP
+#endif  // BOOST_REDIS_ADAPTER_DETAIL_RESPONSE_TRAITS_HPP

include/boost/redis/adapter/detail/result_traits.hpp

@@ -1,4 +1,4 @@
-/* Copyright (c) 2018-2023 Marcelo Zimbres Silva (mzimbres@gmail.com)
+/* Copyright (c) 2018-2024 Marcelo Zimbres Silva (mzimbres@gmail.com)
  *
  * Distributed under the Boost Software License, Version 1.0. (See
  * accompanying file LICENSE.txt)
@@ -7,21 +7,23 @@
 #ifndef BOOST_REDIS_ADAPTER_RESPONSE_TRAITS_HPP
 #define BOOST_REDIS_ADAPTER_RESPONSE_TRAITS_HPP
 
-#include <boost/redis/error.hpp>
-#include <boost/redis/resp3/type.hpp>
-#include <boost/redis/ignore.hpp>
 #include <boost/redis/adapter/detail/adapters.hpp>
-#include <boost/redis/adapter/result.hpp>
 #include <boost/redis/adapter/ignore.hpp>
+#include <boost/redis/adapter/result.hpp>
+#include <boost/redis/error.hpp>
+#include <boost/redis/ignore.hpp>
+#include <boost/redis/resp3/type.hpp>
+#include <boost/redis/resp3/tree.hpp>
+#include <boost/redis/resp3/flat_tree.hpp>
+
 #include <boost/mp11.hpp>
 
-#include <vector>
-#include <tuple>
 #include <string_view>
+#include <tuple>
 #include <variant>
+#include <vector>
 
-namespace boost::redis::adapter::detail
-{
+namespace boost::redis::adapter::detail {
 
 /* Traits class for response objects.
  *
@@ -30,7 +32,7 @@ namespace boost::redis::adapter::detail
  */
 template <class Result>
 struct result_traits {
-   using adapter_type = adapter::detail::wrapper<typename std::decay<Result>::type>;
+   using adapter_type = wrapper<typename std::decay<Result>::type>;
    static auto adapt(Result& r) noexcept { return adapter_type{&r}; }
 };
 
@@ -56,36 +58,59 @@ struct result_traits<result<resp3::basic_node<T>>> {
 };
 
 template <class String, class Allocator>
-struct result_traits<result<std::vector<resp3::basic_node<String>, Allocator>>> {
+struct result_traits<result<resp3::basic_tree<String, Allocator>>> {
    using response_type = result<std::vector<resp3::basic_node<String>, Allocator>>;
    using adapter_type = adapter::detail::general_aggregate<response_type>;
    static auto adapt(response_type& v) noexcept { return adapter_type{&v}; }
 };
 
+template <class String>
+struct result_traits<resp3::basic_tree<String>> {
+   using response_type = resp3::basic_tree<String>;
+   using adapter_type = adapter::detail::general_aggregate<response_type>;
+   static auto adapt(response_type& v) noexcept { return adapter_type{&v}; }
+};
+
+template <>
+struct result_traits<generic_flat_response> {
+   using response_type = generic_flat_response;
+   using adapter_type = general_aggregate<response_type>;
+   static auto adapt(response_type& v) noexcept { return adapter_type{&v}; }
+};
+
+template <>
+struct result_traits<resp3::flat_tree> {
+   using response_type = resp3::flat_tree;
+   using adapter_type = general_aggregate<response_type>;
+   static auto adapt(response_type& v) noexcept { return adapter_type{&v}; }
+};
+
 template <class T>
 using adapter_t = typename result_traits<std::decay_t<T>>::adapter_type;
 
-template<class T>
+template <class T>
 auto internal_adapt(T& t) noexcept
-   { return result_traits<std::decay_t<T>>::adapt(t); }
+{
+   return result_traits<std::decay_t<T>>::adapt(t);
+}
 
 template <std::size_t N>
 struct assigner {
-  template <class T1, class T2>
-  static void assign(T1& dest, T2& from)
-  {
-     dest[N].template emplace<N>(internal_adapt(std::get<N>(from)));
-     assigner<N - 1>::assign(dest, from);
-  }
+   template <class T1, class T2>
+   static void assign(T1& dest, T2& from)
+   {
+      dest[N].template emplace<N>(internal_adapt(std::get<N>(from)));
+      assigner<N - 1>::assign(dest, from);
+   }
 };
 
 template <>
 struct assigner<0> {
-  template <class T1, class T2>
-  static void assign(T1& dest, T2& from)
-  {
-     dest[0].template emplace<0>(internal_adapt(std::get<0>(from)));
-  }
+   template <class T1, class T2>
+   static void assign(T1& dest, T2& from)
+   {
+      dest[0].template emplace<0>(internal_adapt(std::get<0>(from)));
+   }
 };
 
 template <class Tuple>
@@ -94,16 +119,16 @@ class static_aggregate_adapter;
 template <class Tuple>
 class static_aggregate_adapter<result<Tuple>> {
 private:
-   using adapters_array_type = 
-      std::array<
-         mp11::mp_rename<
-            mp11::mp_transform<
-               adapter_t, Tuple>,
-               std::variant>,
-         std::tuple_size<Tuple>::value>;
+   using adapters_array_type = std::array<
+      mp11::mp_rename<mp11::mp_transform<adapter_t, Tuple>, std::variant>,
+      std::tuple_size<Tuple>::value>;
 
+   // Tuple element we are currently on.
    std::size_t i_ = 0;
+
+   // Nested aggregate element counter.
    std::size_t aggregate_size_ = 0;
+
    adapters_array_type adapters_;
    result<Tuple>* res_ = nullptr;
 
@@ -117,47 +142,73 @@ public:
    }
 
    template <class String>
-   void count(resp3::basic_node<String> const& nd)
+   void count(resp3::basic_node<String> const& elem)
    {
-      if (nd.depth == 1) {
-         if (is_aggregate(nd.data_type))
-            aggregate_size_ = element_multiplicity(nd.data_type) * nd.aggregate_size;
-         else
-            ++i_;
-
-         return;
+      if (elem.depth == 1 && is_aggregate(elem.data_type)) {
+         aggregate_size_ = element_multiplicity(elem.data_type) * elem.aggregate_size;
       }
 
-      if (--aggregate_size_ == 0)
-         ++i_;
+      if (aggregate_size_ == 0) {
+         i_ += 1;
+      } else {
+         aggregate_size_ -= 1;
+      }
+   }
+
+   void on_init()
+   {
+      using std::visit;
+      for (auto& adapter : adapters_) {
+         visit(
+            [&](auto& arg) {
+               arg.on_init();
+            },
+            adapter);
+      }
+   }
+
+   void on_done()
+   {
+      using std::visit;
+      for (auto& adapter : adapters_) {
+         visit(
+            [&](auto& arg) {
+               arg.on_done();
+            },
+            adapter);
+      }
    }
 
    template <class String>
-   void operator()(resp3::basic_node<String> const& nd, system::error_code& ec)
+   void on_node(resp3::basic_node<String> const& elem, system::error_code& ec)
    {
       using std::visit;
 
-      if (nd.depth == 0) {
-         auto const real_aggr_size = nd.aggregate_size * element_multiplicity(nd.data_type);
+      if (elem.depth == 0) {
+         auto const multiplicity = element_multiplicity(elem.data_type);
+         auto const real_aggr_size = elem.aggregate_size * multiplicity;
          if (real_aggr_size != std::tuple_size<Tuple>::value)
             ec = redis::error::incompatible_size;
 
          return;
       }
 
-      visit([&](auto& arg){arg(nd, ec);}, adapters_[i_]);
-      count(nd);
+      visit(
+         [&](auto& arg) {
+            arg.on_node(elem, ec);
+         },
+         adapters_.at(i_));
+      count(elem);
    }
 };
 
 template <class... Ts>
-struct result_traits<result<std::tuple<Ts...>>>
-{
+struct result_traits<result<std::tuple<Ts...>>> {
    using response_type = result<std::tuple<Ts...>>;
    using adapter_type = static_aggregate_adapter<response_type>;
    static auto adapt(response_type& r) noexcept { return adapter_type{&r}; }
 };
 
-} // boost::redis::adapter::detail
+}  // namespace boost::redis::adapter::detail
 
-#endif // BOOST_REDIS_ADAPTER_RESPONSE_TRAITS_HPP
+#endif  // BOOST_REDIS_ADAPTER_RESPONSE_TRAITS_HPP

include/boost/redis/adapter/ignore.hpp

@@ -1,4 +1,4 @@
-/* Copyright (c) 2018-2023 Marcelo Zimbres Silva (mzimbres@gmail.com)
+/* Copyright (c) 2018-2025 Marcelo Zimbres Silva (mzimbres@gmail.com)
  *
  * Distributed under the Boost Software License, Version 1.0. (See
  * accompanying file LICENSE.txt)
@@ -7,31 +7,32 @@
 #ifndef BOOST_REDIS_ADAPTER_IGNORE_HPP
 #define BOOST_REDIS_ADAPTER_IGNORE_HPP
 
-#include <boost/redis/resp3/node.hpp>
 #include <boost/redis/error.hpp>
+#include <boost/redis/resp3/node.hpp>
+
 #include <boost/system/error_code.hpp>
-#include <string>
 
-namespace boost::redis::adapter
-{
+namespace boost::redis::adapter {
 
-/** @brief An adapter that ignores responses
- *  @ingroup high-level-api
+/** @brief An adapter that ignores responses.
  *
  *  RESP3 errors won't be ignored.
  */
 struct ignore {
-   void operator()(resp3::basic_node<std::string_view> const& nd, system::error_code& ec)
+   void on_init() { }
+   void on_done() { }
+
+   void on_node(resp3::basic_node<std::string_view> const& nd, system::error_code& ec)
    {
       switch (nd.data_type) {
          case resp3::type::simple_error: ec = redis::error::resp3_simple_error; break;
-         case resp3::type::blob_error: ec = redis::error::resp3_blob_error; break;
-         case resp3::type::null: ec = redis::error::resp3_null; break;
-         default:;
+         case resp3::type::blob_error:   ec = redis::error::resp3_blob_error; break;
+         case resp3::type::null:         ec = redis::error::resp3_null; break;
+         default:                        ;
       }
    }
 };
 
-} // boost::redis::adapter
+}  // namespace boost::redis::adapter
 
-#endif // BOOST_REDIS_ADAPTER_IGNORE_HPP
+#endif  // BOOST_REDIS_ADAPTER_IGNORE_HPP

include/boost/redis/adapter/result.hpp

@@ -1,5 +1,5 @@
 
-/* Copyright (c) 2018-2023 Marcelo Zimbres Silva (mzimbres@gmail.com)
+/* Copyright (c) 2018-2024 Marcelo Zimbres Silva (mzimbres@gmail.com)
  *
  * Distributed under the Boost Software License, Version 1.0. (See
  * accompanying file LICENSE.txt)
@@ -8,17 +8,17 @@
 #ifndef BOOST_REDIS_ADAPTER_RESULT_HPP
 #define BOOST_REDIS_ADAPTER_RESULT_HPP
 
-#include <boost/redis/resp3/type.hpp>
+#include <boost/redis/detail/resp3_type_to_error.hpp>
 #include <boost/redis/error.hpp>
+#include <boost/redis/resp3/type.hpp>
+
 #include <boost/system/result.hpp>
+
 #include <string>
 
-namespace boost::redis::adapter
-{
+namespace boost::redis::adapter {
 
-/** @brief Stores any resp3 error
- *  @ingroup high-level-api
- */
+/// Stores any resp3 error.
 struct error {
    /// RESP3 error data type.
    resp3::type data_type = resp3::type::invalid;
@@ -44,38 +44,24 @@ inline bool operator==(error const& a, error const& b)
  *  @param a Left hand side error object.
  *  @param b Right hand side error object.
  */
-inline bool operator!=(error const& a, error const& b)
-{
-   return !(a == b);
-}
+inline bool operator!=(error const& a, error const& b) { return !(a == b); }
 
-/** @brief Stores response to individual Redis commands
- *  @ingroup high-level-api
- */
+/// Stores response to individual Redis commands.
 template <class Value>
 using result = system::result<Value, error>;
 
-BOOST_NORETURN inline void
-throw_exception_from_error(error const & e, boost::source_location const &)
+/**
+ * @brief Allows using @ref error with `boost::system::result`.
+ * @param e The error to throw.
+ * @relates error
+ */
+BOOST_NORETURN inline void throw_exception_from_error(error const& e, boost::source_location const&)
 {
-   system::error_code ec;
-   switch (e.data_type) {
-      case resp3::type::simple_error:
-         ec = redis::error::resp3_simple_error;
-         break;
-      case resp3::type::blob_error:
-         ec = redis::error::resp3_blob_error;
-         break;
-      case resp3::type::null:
-         ec = redis::error::resp3_null;
-         break;
-      default:
-         BOOST_ASSERT_MSG(false, "Unexpected data type.");
-   }
-
-   throw system::system_error(ec, e.diagnostic);
+   throw system::system_error(
+      system::error_code(detail::resp3_type_to_error(e.data_type)),
+      e.diagnostic);
 }
 
-} // boost::redis::adapter
+}  // namespace boost::redis::adapter
 
-#endif // BOOST_REDIS_ADAPTER_RESULT_HPP
+#endif  // BOOST_REDIS_ADAPTER_RESULT_HPP

include/boost/redis/config.hpp

@@ -1,4 +1,4 @@
-/* Copyright (c) 2018-2023 Marcelo Zimbres Silva (mzimbres@gmail.com)
+/* Copyright (c) 2018-2024 Marcelo Zimbres Silva (mzimbres@gmail.com)
  *
  * Distributed under the Boost Software License, Version 1.0. (See
  * accompanying file LICENSE.txt)
@@ -7,16 +7,17 @@
 #ifndef BOOST_REDIS_CONFIG_HPP
 #define BOOST_REDIS_CONFIG_HPP
 
-#include <string>
+#include <boost/redis/request.hpp>
+
 #include <chrono>
+#include <limits>
 #include <optional>
+#include <string>
+#include <vector>
 
-namespace boost::redis
-{
+namespace boost::redis {
 
-/** @brief Address of a Redis server
- *  @ingroup high-level-api
- */
+/// Address of a Redis server.
 struct address {
    /// Redis host.
    std::string host = "127.0.0.1";
@@ -24,62 +25,328 @@ struct address {
    std::string port = "6379";
 };
 
-/** @brief Configure parameters used by the connection classes
- *  @ingroup high-level-api
+/** @brief Compares two addresses for equality.
+ *  @relates address
+ *
+ *  @param a Left hand side address.
+ *  @param b Right hand side address.
  */
-struct config {
-   /// Uses SSL instead of a plain connection.
+inline bool operator==(address const& a, address const& b)
+{
+   return a.host == b.host && a.port == b.port;
+}
+
+/** @brief Compares two addresses for inequality.
+ *  @relates address
+ *
+ *  @param a Left hand side address.
+ *  @param b Right hand side address.
+ */
+inline bool operator!=(address const& a, address const& b) { return !(a == b); }
+
+/// Identifies the possible roles of a Redis server.
+enum class role
+{
+   /// The server is a master.
+   master,
+
+   /// The server is a replica.
+   replica,
+};
+
+/// Configuration values to use when using Sentinel.
+struct sentinel_config {
+   /**
+    * @brief A list of (hostname, port) pairs where the Sentinels are listening.
+    *
+    * Sentinels in this list will be contacted in order, until a successful
+    * connection is made. At this point, the `SENTINEL SENTINELS` command
+    * will be used to retrieve any additional Sentinels monitoring the configured master.
+    * Thus, it is not required to keep this list comprehensive - if Sentinels are added
+    * later, they will be detected at runtime.
+    *
+    * Sentinel will only be used if this value is not empty.
+    *
+    * Numeric IP addresses are also allowed as hostnames.
+    */
+   std::vector<address> addresses{};
+
+   /**
+    * @brief The name of the master to connect to, as configured in the
+    *        `sentinel monitor` statement in `sentinel.conf`.
+    *
+    * This field is required even when connecting to replicas.
+    */
+   std::string master_name{};
+
+   /**
+    * @brief Whether connections to Sentinels should use TLS or not.
+    *        Does not affect connections to masters.
+    *
+    * When set to `true`, physical connections to Sentinels will be established
+    * using TLS. This setting does *not* influence how masters and replicas are contacted.
+    * To use TLS when connecting to these, set @ref config::use_ssl to `true`.
+    */
    bool use_ssl = false;
 
-   /// Address of the Redis server.
+   /**
+    * @brief A request to be sent to Sentinels upon connection establishment.
+    *
+    * This request is executed every time a Sentinel is contacted, and before
+    * commands like `SENTINEL GET-MASTER-NAME-BY-ADDR` are run.
+    * By default, this field contains a `HELLO 3` command.
+    * You can use this request to set up any authorization required by Sentinels.
+    *
+    * This request should ensure that the connection is upgraded to RESP3
+    * by executing `HELLO 3` or similar. RESP2 is not supported yet.
+    */
+   request setup = detail::make_hello_request();
+
+   /**
+    * @brief Time span that the Sentinel resolve operation is allowed to elapse.
+    *        Does not affect connections to masters and replicas, controlled by @ref config::resolve_timeout.
+    */
+   std::chrono::steady_clock::duration resolve_timeout = std::chrono::milliseconds{500};
+
+   /**
+    * @brief Time span that the Sentinel connect operation is allowed to elapse.
+    *        Does not affect connections to masters and replicas, controlled by @ref config::connect_timeout.
+    */
+   std::chrono::steady_clock::duration connect_timeout = std::chrono::milliseconds{500};
+
+   /**
+    * @brief Time span that the Sentinel TLS handshake operation is allowed to elapse.
+    *        Does not affect connections to masters and replicas, controlled by @ref config::ssl_handshake_timeout.
+    */
+   std::chrono::steady_clock::duration ssl_handshake_timeout = std::chrono::seconds{5};
+
+   /**
+    * @brief Time span that the Sentinel request/response exchange is allowed to elapse.
+    *        Includes executing the commands in @ref setup and the commands required to
+    *        resolve the server's address.
+    */
+   std::chrono::steady_clock::duration request_timeout = std::chrono::seconds{5};
+
+   /**
+    * @brief Whether to connect to a Redis master or to a replica.
+    *
+    * The library resolves and connects to the Redis master, by default.
+    * Set this value to @ref role::replica to connect to one of the replicas
+    * of the master identified by @ref master_name.
+    * The particular replica will be chosen randomly.
+    */
+   role server_role = role::master;
+};
+
+/// Configure parameters used by the connection classes.
+struct config {
+   /**
+    * @brief Whether to use TLS instead of plaintext connections.
+    *
+    * When using Sentinel, configures whether to use TLS when connecting to masters and replicas.
+    * Use @ref sentinel_config::use_ssl to control TLS for Sentinels.
+    */
+   bool use_ssl = false;
+
+   /// For TCP connections, hostname and port of the Redis server. Ignored when using Sentinel.
    address addr = address{"127.0.0.1", "6379"};
 
-   /** @brief Username passed to the
-    * [HELLO](https://redis.io/commands/hello/) command.  If left
-    * empty `HELLO` will be sent without authentication parameters.
+   /**
+    * @brief The UNIX domain socket path where the server is listening.
+    *
+    * If non-empty, communication with the server will happen using
+    * UNIX domain sockets, and @ref addr will be ignored.
+    * 
+    * UNIX domain sockets can't be used with SSL: if `unix_socket` is non-empty,
+    * @ref use_ssl must be `false`. UNIX domain sockets can't be used with Sentinel, either.
+    *
+    * UNIX domain sockets can't be used with Sentinel.
     */
-   std::string username;
+   std::string unix_socket;
 
-   /** @brief Password passed to the
-    * [HELLO](https://redis.io/commands/hello/) command.  If left
-    * empty `HELLO` will be sent without authentication parameters.
+   /** @brief Username used for authentication during connection establishment.
+    * 
+    * If @ref use_setup is false (the default), during connection establishment,
+    * authentication is performed by sending a `HELLO` command.
+    * This field contains the username to employ.
+    *
+    * If the username equals the literal `"default"` (the default)
+    * and no password is specified, the `HELLO` command is sent
+    * without authentication parameters.
+    *
+    * When using Sentinel, this setting applies to masters and replicas.
+    * Use @ref sentinel_config::setup to configure authorization for Sentinels.
+    */
+   std::string username = "default";
+
+   /** @brief Password used for authentication during connection establishment.
+    * 
+    * If @ref use_setup is false (the default), during connection establishment,
+    * authentication is performed by sending a `HELLO` command.
+    * This field contains the password to employ.
+    *
+    * If the username equals the literal `"default"` (the default)
+    * and no password is specified, the `HELLO` command is sent
+    * without authentication parameters.
+    *
+    * When using Sentinel, this setting applies to masters and replicas.
+    * Use @ref sentinel_config::setup to configure authorization for Sentinels.
     */
    std::string password;
 
-   /// Client name parameter of the [HELLO](https://redis.io/commands/hello/) command.
+   /** @brief Client name parameter to use during connection establishment.
+    * 
+    * If @ref use_setup is false (the default), during connection establishment,
+    * a `HELLO` command is sent. If this field is not empty, the `HELLO` command
+    * will contain a `SETNAME` subcommand containing this value.
+    *
+    * When using Sentinel, this setting applies to masters and replicas.
+    * Use @ref sentinel_config::setup to configure this value for Sentinels.
+    */
    std::string clientname = "Boost.Redis";
 
-   /// Database that will be passed to the [SELECT](https://redis.io/commands/hello/) command.
+   /** @brief Database index to pass to the `SELECT` command during connection establishment.
+    * 
+    * If @ref use_setup is false (the default), and this field is set to a
+    * non-empty optional, and its value is different than zero,
+    * a `SELECT` command will be issued during connection establishment to set the logical
+    * database index. By default, no `SELECT` command is sent.
+    *
+    * When using Sentinel, this setting applies to masters and replicas.
+    */
    std::optional<int> database_index = 0;
 
-   /// Message used by the health-checker in `boost::redis::connection::async_run`.
+   /// Message used by `PING` commands sent by the health checker.
    std::string health_check_id = "Boost.Redis";
 
-   /// Logger prefix, see `boost::redis::logger`.
+   /**
+    * @brief (Deprecated) Sets the logger prefix, a string printed before log messages.
+    * 
+    * Setting a prefix in this struct is deprecated. If you need to change how log messages
+    * look like, please construct a logger object passing a formatting function, and use that
+    * logger in connection's constructor. This member will be removed in subsequent releases.
+    */
    std::string log_prefix = "(Boost.Redis) ";
 
-   /// Time the resolve operation is allowed to last.
+   /**
+    * @brief Time span that the resolve operation is allowed to elapse.
+    *        When using Sentinel, this setting applies to masters and replicas.
+    */
    std::chrono::steady_clock::duration resolve_timeout = std::chrono::seconds{10};
 
-   /// Time the connect operation is allowed to last.
+   /**
+    * @brief Time span that the connect operation is allowed to elapse.
+    *        When using Sentinel, this setting applies to masters and replicas.
+    */
    std::chrono::steady_clock::duration connect_timeout = std::chrono::seconds{10};
 
-   /// Time the SSL handshake operation is allowed to last.
+   /**
+    * @brief Time span that the SSL handshake operation is allowed to elapse.
+    *        When using Sentinel, this setting applies to masters and replicas.
+    */
    std::chrono::steady_clock::duration ssl_handshake_timeout = std::chrono::seconds{10};
 
-   /** Health checks interval.  
-    *  
-    *  To disable health-checks pass zero as duration.
+   /** @brief Time span between successive health checks.
+    *  Set to zero to disable health-checks.
+    *
+    * When this value is set to a non-zero duration, @ref basic_connection::async_run
+    * will issue `PING` commands whenever no command is sent to the server for more
+    * than `health_check_interval`. You can configure the message passed to the `PING`
+    * command using @ref health_check_id.
+    *
+    * Enabling health checks also sets timeouts to individual network
+    * operations. The connection is considered dead if:
+    *
+    * @li No byte can be written to the server after `health_check_interval`.
+    * @li No byte is read from the server after `2 * health_check_interval`.
+    *
+    * If the health checker finds that the connection is unresponsive, it will be closed,
+    * and a reconnection will be triggered, as if a network error had occurred.
+    *
+    * The exact timeout values are *not* part of the interface, and might change
+    * in future versions.
+    *
+    * When using Sentinel, this setting applies to masters and replicas.
+    * Sentinels are not health-checked.
     */
    std::chrono::steady_clock::duration health_check_interval = std::chrono::seconds{2};
 
-   /** @brief Time waited before trying a reconnection.
-    *  
-    *  To disable reconnection pass zero as duration.
+   /** @brief Time span to wait between successive connection retries.
+    *         Set to zero to disable reconnection.
+    *
+    * When using Sentinel, this setting applies to masters, replicas and Sentinels.
+    * If none of the configured Sentinels can be contacted, this time span will
+    * be waited before trying again. After a connection error with a master or replica
+    * is encountered, this time span will be waited before contacting Sentinels again.
     */
    std::chrono::steady_clock::duration reconnect_wait_interval = std::chrono::seconds{1};
+
+   /** @brief Maximum size of the socket read-buffer in bytes.
+    *  
+    * Sets a limit on how much data is allowed to be read into the
+    * read buffer. It can be used to prevent DDOS.
+    *
+    * When using Sentinel, this setting applies to masters, replicas and Sentinels.
+    */
+   std::size_t max_read_size = (std::numeric_limits<std::size_t>::max)();
+
+   /** @brief Grow size of the read buffer.
+    *
+    * The size by which the read buffer grows when more space is
+    * needed. This can help avoiding some memory allocations. Once the
+    * maximum size is reached no more memory allocations are made
+    * since the buffer is reused.
+    *
+    * When using Sentinel, this setting applies to masters, replicas and Sentinels.
+    */
+   std::size_t read_buffer_append_size = 4096;
+
+   /** @brief Enables using a custom requests during connection establishment.
+    * 
+    * If set to true, the @ref setup member will be sent to the server immediately after
+    * connection establishment. Every time a reconnection happens, the setup
+    * request will be executed before any other request.
+    * It can be used to perform authentication,
+    * subscribe to channels or select a database index.
+    *
+    * When set to true, *the custom setup request replaces the built-in HELLO
+    * request generated by the library*. The @ref username, @ref password,
+    * @ref clientname and @ref database_index fields *will be ignored*.
+    *
+    * By default, @ref setup contains a `"HELLO 3"` command, which upgrades the
+    * protocol to RESP3. You might modify this request as you like,
+    * but you should ensure that the resulting connection uses RESP3.
+    *
+    * To prevent sending any setup request at all, set this field to true
+    * and @ref setup to an empty request. This can be used to interface with
+    * systems that don't support `HELLO`.
+    *
+    * By default, this field is false, and @ref setup will not be used.
+    *
+    * When using Sentinel, this setting applies to masters and replicas.
+    * Use @ref sentinel_config::setup for Sentinels.
+    */
+   bool use_setup = false;
+
+   /** @brief Request to be executed after connection establishment.
+    *
+    * This member is only used if @ref use_setup is `true`. Please consult
+    * @ref use_setup docs for more info.
+    *
+    * By default, `setup` contains a `"HELLO 3"` command.
+    *
+    * When using Sentinel, this setting applies to masters and replicas.
+    * Use @ref sentinel_config::setup for Sentinels.
+    */
+   request setup = detail::make_hello_request();
+
+   /**
+    * @brief Configuration values for Sentinel. Sentinel is enabled only if
+    *        @ref sentinel_config::addresses is not empty.
+    */
+   sentinel_config sentinel{};
 };
 
-} // boost::redis
+}  // namespace boost::redis
 
-#endif // BOOST_REDIS_CONFIG_HPP
+#endif  // BOOST_REDIS_CONFIG_HPP

include/boost/redis/detail/connect_fsm.hpp

@@ -0,0 +1,91 @@
+//
+// Copyright (c) 2025 Marcelo Zimbres Silva (mzimbres@gmail.com),
+// Ruben Perez Hidalgo (rubenperez038 at gmail dot com)
+//
+// Distributed under the Boost Software License, Version 1.0. (See accompanying
+// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+//
+
+#ifndef BOOST_REDIS_CONNECT_FSM_HPP
+#define BOOST_REDIS_CONNECT_FSM_HPP
+
+#include <boost/asio/cancellation_type.hpp>
+#include <boost/asio/ip/tcp.hpp>
+#include <boost/system/error_code.hpp>
+
+// Sans-io algorithm for redis_stream::async_connect, as a finite state machine
+
+namespace boost::redis::detail {
+
+struct buffered_logger;
+
+// What transport is redis_stream using?
+enum class transport_type
+{
+   tcp,          // plaintext TCP
+   tcp_tls,      // TLS over TCP
+   unix_socket,  // UNIX domain sockets
+};
+
+struct redis_stream_state {
+   transport_type type{transport_type::tcp};
+   bool ssl_stream_used{false};
+};
+
+// What should we do next?
+enum class connect_action_type
+{
+   unix_socket_close,    // Close the UNIX socket, to discard state
+   unix_socket_connect,  // Connect to the UNIX socket
+   tcp_resolve,          // Name resolution
+   tcp_connect,          // TCP connect
+   ssl_stream_reset,     // Re-create the SSL stream, to discard state
+   ssl_handshake,        // SSL handshake
+   done,                 // Complete the async op
+};
+
+struct connect_action {
+   connect_action_type type;
+   system::error_code ec;
+
+   connect_action(connect_action_type type) noexcept
+   : type{type}
+   { }
+
+   connect_action(system::error_code ec) noexcept
+   : type{connect_action_type::done}
+   , ec{ec}
+   { }
+};
+
+class connect_fsm {
+   int resume_point_{0};
+   buffered_logger* lgr_{nullptr};
+
+public:
+   connect_fsm(buffered_logger& lgr) noexcept
+   : lgr_(&lgr)
+   { }
+
+   connect_action resume(
+      system::error_code ec,
+      const asio::ip::tcp::resolver::results_type& resolver_results,
+      redis_stream_state& st,
+      asio::cancellation_type_t cancel_state);
+
+   connect_action resume(
+      system::error_code ec,
+      const asio::ip::tcp::endpoint& selected_endpoint,
+      redis_stream_state& st,
+      asio::cancellation_type_t cancel_state);
+
+   connect_action resume(
+      system::error_code ec,
+      redis_stream_state& st,
+      asio::cancellation_type_t cancel_state);
+
+};  // namespace boost::redis::detail
+
+}  // namespace boost::redis::detail
+
+#endif

include/boost/redis/detail/connect_params.hpp

@@ -0,0 +1,65 @@
+//
+// Copyright (c) 2025 Marcelo Zimbres Silva (mzimbres@gmail.com),
+// Ruben Perez Hidalgo (rubenperez038 at gmail dot com)
+//
+// Distributed under the Boost Software License, Version 1.0. (See accompanying
+// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+//
+
+#ifndef BOOST_REDIS_CONNECT_PARAMS_HPP
+#define BOOST_REDIS_CONNECT_PARAMS_HPP
+
+// Parameters used by redis_stream::async_connect
+
+#include <boost/redis/config.hpp>
+#include <boost/redis/detail/connect_fsm.hpp>
+
+#include <chrono>
+#include <string_view>
+
+namespace boost::redis::detail {
+
+// Fully identifies where a server is listening. Reference type.
+class any_address_view {
+   transport_type type_;
+   union {
+      const address* tcp_;
+      std::string_view unix_;
+   };
+
+public:
+   any_address_view(const address& addr, bool use_ssl) noexcept
+   : type_(use_ssl ? transport_type::tcp_tls : transport_type::tcp)
+   , tcp_(&addr)
+   { }
+
+   explicit any_address_view(std::string_view unix_socket) noexcept
+   : type_(transport_type::unix_socket)
+   , unix_(unix_socket)
+   { }
+
+   transport_type type() const { return type_; }
+
+   const address& tcp_address() const
+   {
+      BOOST_ASSERT(type_ == transport_type::tcp || type_ == transport_type::tcp_tls);
+      return *tcp_;
+   }
+
+   std::string_view unix_socket() const
+   {
+      BOOST_ASSERT(type_ == transport_type::unix_socket);
+      return unix_;
+   }
+};
+
+struct connect_params {
+   any_address_view addr;
+   std::chrono::steady_clock::duration resolve_timeout;
+   std::chrono::steady_clock::duration connect_timeout;
+   std::chrono::steady_clock::duration ssl_handshake_timeout;
+};
+
+}  // namespace boost::redis::detail
+
+#endif  // BOOST_REDIS_CONNECTOR_HPP

include/boost/redis/detail/connection_base.hpp

@@ -1,958 +0,0 @@
-/* Copyright (c) 2018-2023 Marcelo Zimbres Silva (mzimbres@gmail.com)
- *
- * Distributed under the Boost Software License, Version 1.0. (See
- * accompanying file LICENSE.txt)
- */
-
-#ifndef BOOST_REDIS_CONNECTION_BASE_HPP
-#define BOOST_REDIS_CONNECTION_BASE_HPP
-
-#include <boost/redis/adapter/adapt.hpp>
-#include <boost/redis/detail/helper.hpp>
-#include <boost/redis/error.hpp>
-#include <boost/redis/operation.hpp>
-#include <boost/redis/request.hpp>
-#include <boost/redis/resp3/type.hpp>
-#include <boost/redis/config.hpp>
-#include <boost/redis/detail/runner.hpp>
-#include <boost/redis/usage.hpp>
-
-#include <boost/system.hpp>
-#include <boost/asio/basic_stream_socket.hpp>
-#include <boost/asio/bind_executor.hpp>
-#include <boost/asio/experimental/parallel_group.hpp>
-#include <boost/asio/ip/tcp.hpp>
-#include <boost/asio/steady_timer.hpp>
-#include <boost/asio/write.hpp>
-#include <boost/assert.hpp>
-#include <boost/core/ignore_unused.hpp>
-#include <boost/asio/ssl/stream.hpp>
-#include <boost/asio/read_until.hpp>
-#include <boost/asio/buffer.hpp>
-#include <boost/asio/experimental/channel.hpp>
-
-#include <algorithm>
-#include <array>
-#include <chrono>
-#include <deque>
-#include <memory>
-#include <string_view>
-#include <type_traits>
-#include <functional>
-
-namespace boost::redis::detail
-{
-
-template <class DynamicBuffer>
-std::string_view buffer_view(DynamicBuffer buf) noexcept
-{
-   char const* start = static_cast<char const*>(buf.data(0, buf.size()).data());
-   return std::string_view{start, std::size(buf)};
-}
-
-template <class AsyncReadStream, class DynamicBuffer>
-class append_some_op {
-private:
-   AsyncReadStream& stream_;
-   DynamicBuffer buf_;
-   std::size_t size_ = 0;
-   std::size_t tmp_ = 0;
-   asio::coroutine coro_{};
-
-public:
-   append_some_op(AsyncReadStream& stream, DynamicBuffer buf, std::size_t size)
-   : stream_ {stream}
-   , buf_ {std::move(buf)}
-   , size_{size}
-   { }
-
-   template <class Self>
-   void operator()( Self& self
-                  , system::error_code ec = {}
-                  , std::size_t n = 0)
-   {
-      BOOST_ASIO_CORO_REENTER (coro_)
-      {
-         tmp_ = buf_.size();
-         buf_.grow(size_);
-
-         BOOST_ASIO_CORO_YIELD
-         stream_.async_read_some(buf_.data(tmp_, size_), std::move(self));
-         if (ec) {
-            self.complete(ec, 0);
-            return;
-         }
-
-         buf_.shrink(buf_.size() - tmp_ - n);
-         self.complete({}, n);
-      }
-   }
-};
-
-template <class AsyncReadStream, class DynamicBuffer, class CompletionToken>
-auto
-async_append_some(
-   AsyncReadStream& stream,
-   DynamicBuffer buffer,
-   std::size_t size,
-   CompletionToken&& token)
-{
-   return asio::async_compose
-      < CompletionToken
-      , void(system::error_code, std::size_t)
-      >(append_some_op<AsyncReadStream, DynamicBuffer> {stream, buffer, size}, token, stream);
-}
-
-template <class Conn>
-struct exec_op {
-   using req_info_type = typename Conn::req_info;
-   using adapter_type = typename Conn::adapter_type;
-
-   Conn* conn_ = nullptr;
-   std::shared_ptr<req_info_type> info_ = nullptr;
-   asio::coroutine coro{};
-
-   template <class Self>
-   void operator()(Self& self , system::error_code ec = {})
-   {
-      BOOST_ASIO_CORO_REENTER (coro)
-      {
-         // Check whether the user wants to wait for the connection to
-         // be stablished.
-         if (info_->req_->get_config().cancel_if_not_connected && !conn_->is_open()) {
-            BOOST_ASIO_CORO_YIELD
-            asio::post(std::move(self));
-            return self.complete(error::not_connected, 0);
-         }
-
-         conn_->add_request_info(info_);
-
-EXEC_OP_WAIT:
-         BOOST_ASIO_CORO_YIELD
-         info_->async_wait(std::move(self));
-         BOOST_ASSERT(ec == asio::error::operation_aborted);
-
-         if (info_->ec_) {
-            self.complete(info_->ec_, 0);
-            return;
-         }
-
-         if (info_->stop_requested()) {
-            // Don't have to call remove_request as it has already
-            // been by cancel(exec).
-            return self.complete(ec, 0);
-         }
-
-         if (is_cancelled(self)) {
-            if (info_->is_written()) {
-               using c_t = asio::cancellation_type;
-               auto const c = self.get_cancellation_state().cancelled();
-               if ((c & c_t::terminal) != c_t::none) {
-                  // Cancellation requires closing the connection
-                  // otherwise it stays in inconsistent state.
-                  conn_->cancel(operation::run);
-                  return self.complete(ec, 0);
-               } else {
-                  // Can't implement other cancelation types, ignoring.
-                  self.get_cancellation_state().clear();
-
-                  // TODO: Find out a better way to ignore
-                  // cancelation.
-                  goto EXEC_OP_WAIT;
-               }
-            } else {
-               // Cancelation can be honored.
-               conn_->remove_request(info_);
-               self.complete(ec, 0);
-               return;
-            }
-         }
-
-         self.complete(info_->ec_, info_->read_size_);
-      }
-   }
-};
-
-template <class Conn, class Logger>
-struct run_op {
-   Conn* conn = nullptr;
-   Logger logger_;
-   asio::coroutine coro{};
-
-   template <class Self>
-   void operator()( Self& self
-                  , std::array<std::size_t, 2> order = {}
-                  , system::error_code ec0 = {}
-                  , system::error_code ec1 = {})
-   {
-      BOOST_ASIO_CORO_REENTER (coro)
-      {
-         conn->reset();
-
-         BOOST_ASIO_CORO_YIELD
-         asio::experimental::make_parallel_group(
-            [this](auto token) { return conn->reader(logger_, token);},
-            [this](auto token) { return conn->writer(logger_, token);}
-         ).async_wait(
-            asio::experimental::wait_for_one(),
-            std::move(self));
-
-         if (is_cancelled(self)) {
-            logger_.trace("run-op: canceled. Exiting ...");
-            self.complete(asio::error::operation_aborted);
-            return;
-         }
-
-         logger_.on_run(ec0, ec1);
-
-         switch (order[0]) {
-           case 0: self.complete(ec0); break;
-           case 1: self.complete(ec1); break;
-           default: BOOST_ASSERT(false);
-         }
-      }
-   }
-};
-
-template <class Conn, class Logger>
-struct writer_op {
-   Conn* conn_;
-   Logger logger_;
-   asio::coroutine coro{};
-
-   template <class Self>
-   void operator()( Self& self
-                  , system::error_code ec = {}
-                  , std::size_t n = 0)
-   {
-      ignore_unused(n);
-
-      BOOST_ASIO_CORO_REENTER (coro) for (;;)
-      {
-         while (conn_->coalesce_requests()) {
-            if (conn_->use_ssl())
-               BOOST_ASIO_CORO_YIELD asio::async_write(conn_->next_layer(), asio::buffer(conn_->write_buffer_), std::move(self));
-            else
-               BOOST_ASIO_CORO_YIELD asio::async_write(conn_->next_layer().next_layer(), asio::buffer(conn_->write_buffer_), std::move(self));
-
-            logger_.on_write(ec, conn_->write_buffer_);
-
-            if (ec) {
-               logger_.trace("writer-op: error. Exiting ...");
-               conn_->cancel(operation::run);
-               self.complete(ec);
-               return;
-            }
-
-            if (is_cancelled(self)) {
-               logger_.trace("writer-op: canceled. Exiting ...");
-               self.complete(asio::error::operation_aborted);
-               return;
-            }
-
-            conn_->on_write();
-
-            // A socket.close() may have been called while a
-            // successful write might had already been queued, so we
-            // have to check here before proceeding.
-            if (!conn_->is_open()) {
-               logger_.trace("writer-op: canceled (2). Exiting ...");
-               self.complete({});
-               return;
-            }
-         }
-
-         BOOST_ASIO_CORO_YIELD
-         conn_->writer_timer_.async_wait(std::move(self));
-         if (!conn_->is_open() || is_cancelled(self)) {
-            logger_.trace("writer-op: canceled (3). Exiting ...");
-            // Notice this is not an error of the op, stoping was
-            // requested from the outside, so we complete with
-            // success.
-            self.complete({});
-            return;
-         }
-      }
-   }
-};
-
-template <class Conn, class Logger>
-struct reader_op {
-   using parse_result = typename Conn::parse_result;
-   using parse_ret_type = typename Conn::parse_ret_type;
-   Conn* conn_;
-   Logger logger_;
-   parse_ret_type res_{parse_result::resp, 0};
-   asio::coroutine coro{};
-
-   template <class Self>
-   void operator()( Self& self
-                  , system::error_code ec = {}
-                  , std::size_t n = 0)
-   {
-      ignore_unused(n);
-
-      BOOST_ASIO_CORO_REENTER (coro) for (;;)
-      {
-         // Appends some data to the buffer if necessary.
-         if ((res_.first == parse_result::needs_more) || std::empty(conn_->read_buffer_)) {
-            if (conn_->use_ssl()) {
-               BOOST_ASIO_CORO_YIELD
-               async_append_some(
-                  conn_->next_layer(),
-                  conn_->dbuf_,
-                  conn_->get_suggested_buffer_growth(),
-                  std::move(self));
-            } else {
-               BOOST_ASIO_CORO_YIELD
-               async_append_some(
-                  conn_->next_layer().next_layer(),
-                  conn_->dbuf_,
-                  conn_->get_suggested_buffer_growth(),
-                  std::move(self));
-            }
-
-            logger_.on_read(ec, n);
-
-            // EOF is not treated as error.
-            if (ec == asio::error::eof) {
-               logger_.trace("reader-op: EOF received. Exiting ...");
-               conn_->cancel(operation::run);
-               return self.complete({}); // EOFINAE: EOF is not an error.
-            }
-
-            // The connection is not viable after an error.
-            if (ec) {
-               logger_.trace("reader-op: error. Exiting ...");
-               conn_->cancel(operation::run);
-               self.complete(ec);
-               return;
-            }
-
-            // Somebody might have canceled implicitly or explicitly
-            // while we were suspended and after queueing so we have to
-            // check.
-            if (!conn_->is_open() || is_cancelled(self)) {
-               logger_.trace("reader-op: canceled. Exiting ...");
-               self.complete(ec);
-               return;
-            }
-         }
-
-         res_ = conn_->on_read(buffer_view(conn_->dbuf_), ec);
-         if (ec) {
-            logger_.trace("reader-op: parse error. Exiting ...");
-            conn_->cancel(operation::run);
-            self.complete(ec);
-            return;
-         }
-
-         if (res_.first == parse_result::push) {
-            if (!conn_->receive_channel_.try_send(ec, res_.second)) {
-               BOOST_ASIO_CORO_YIELD
-               conn_->receive_channel_.async_send(ec, res_.second, std::move(self));
-            }
-
-            if (ec) {
-               logger_.trace("reader-op: error. Exiting ...");
-               conn_->cancel(operation::run);
-               self.complete(ec);
-               return;
-            }
-
-            if (!conn_->is_open() || is_cancelled(self)) {
-               logger_.trace("reader-op: canceled (2). Exiting ...");
-               self.complete(asio::error::operation_aborted);
-               return;
-            }
-
-         }
-      }
-   }
-};
-
-/** @brief Base class for high level Redis asynchronous connections.
- *  @ingroup high-level-api
- *
- *  @tparam Executor The executor type.
- *
- */
-template <class Executor>
-class connection_base {
-public:
-   /// Executor type
-   using executor_type = Executor;
-
-   /// Type of the next layer
-   using next_layer_type = asio::ssl::stream<asio::basic_stream_socket<asio::ip::tcp, Executor>>;
-
-   using clock_type = std::chrono::steady_clock;
-   using clock_traits_type = asio::wait_traits<clock_type>;
-   using timer_type = asio::basic_waitable_timer<clock_type, clock_traits_type, executor_type>;
-
-   using this_type = connection_base<Executor>;
-
-   /// Constructs from an executor.
-   connection_base(
-      executor_type ex,
-      asio::ssl::context::method method,
-      std::size_t max_read_size)
-   : ctx_{method}
-   , stream_{std::make_unique<next_layer_type>(ex, ctx_)}
-   , writer_timer_{ex}
-   , receive_channel_{ex, 256}
-   , runner_{ex, {}}
-   , dbuf_{read_buffer_, max_read_size}
-   {
-      set_receive_response(ignore);
-      writer_timer_.expires_at((std::chrono::steady_clock::time_point::max)());
-   }
-
-   /// Returns the ssl context.
-   auto const& get_ssl_context() const noexcept
-      { return ctx_;}
-
-   /// Returns the ssl context.
-   auto& get_ssl_context() noexcept
-      { return ctx_;}
-
-   /// Resets the underlying stream.
-   void reset_stream()
-   {
-      stream_ = std::make_unique<next_layer_type>(writer_timer_.get_executor(), ctx_);
-   }
-
-   /// Returns a reference to the next layer.
-   auto& next_layer() noexcept { return *stream_; }
-
-   /// Returns a const reference to the next layer.
-   auto const& next_layer() const noexcept { return *stream_; }
-
-   /// Returns the associated executor.
-   auto get_executor() {return writer_timer_.get_executor();}
-
-   /// Cancels specific operations.
-   void cancel(operation op)
-   {
-      runner_.cancel(op);
-      if (op == operation::all) {
-         cancel_impl(operation::run);
-         cancel_impl(operation::receive);
-         cancel_impl(operation::exec);
-         return;
-      } 
-
-      cancel_impl(op);
-   }
-
-   template <class Response, class CompletionToken>
-   auto async_exec(request const& req, Response& resp, CompletionToken token)
-   {
-      using namespace boost::redis::adapter;
-      auto f = boost_redis_adapt(resp);
-      BOOST_ASSERT_MSG(req.get_expected_responses() <= f.get_supported_response_size(), "Request and response have incompatible sizes.");
-
-      auto info = std::make_shared<req_info>(req, f, get_executor());
-
-      return asio::async_compose
-         < CompletionToken
-         , void(system::error_code, std::size_t)
-         >(exec_op<this_type>{this, info}, token, writer_timer_);
-   }
-
-   template <class Response, class CompletionToken>
-   [[deprecated("Set the response with set_receive_response and use the other overload.")]]
-   auto async_receive(Response& response, CompletionToken token)
-   {
-      set_receive_response(response);
-      return receive_channel_.async_receive(std::move(token));
-   }
-
-   template <class CompletionToken>
-   auto async_receive(CompletionToken token)
-      { return receive_channel_.async_receive(std::move(token)); }
-
-   std::size_t receive(system::error_code& ec)
-   {
-      std::size_t size = 0;
-
-      auto f = [&](system::error_code const& ec2, std::size_t n)
-      {
-         ec = ec2;
-         size = n;
-      };
-
-      auto const res = receive_channel_.try_receive(f);
-      if (ec)
-         return 0;
-
-      if (!res)
-         ec = error::sync_receive_push_failed;
-
-      return size;
-   }
-
-   template <class Logger, class CompletionToken>
-   auto async_run(config const& cfg, Logger l, CompletionToken token)
-   {
-      runner_.set_config(cfg);
-      l.set_prefix(runner_.get_config().log_prefix);
-      return runner_.async_run(*this, l, std::move(token));
-   }
-
-   template <class Response>
-   void set_receive_response(Response& response)
-   {
-      using namespace boost::redis::adapter;
-      auto g = boost_redis_adapt(response);
-      receive_adapter_ = adapter::detail::make_adapter_wrapper(g);
-   }
-
-   usage get_usage() const noexcept
-      { return usage_; }
-
-private:
-   using receive_channel_type = asio::experimental::channel<executor_type, void(system::error_code, std::size_t)>;
-   using runner_type = runner<executor_type>;
-   using adapter_type = std::function<void(std::size_t, resp3::basic_node<std::string_view> const&, system::error_code&)>;
-   using receiver_adapter_type = std::function<void(resp3::basic_node<std::string_view> const&, system::error_code&)>;
-
-   auto use_ssl() const noexcept
-      { return runner_.get_config().use_ssl;}
-
-   auto cancel_on_conn_lost() -> std::size_t
-   {
-      // Must return false if the request should be removed.
-      auto cond = [](auto const& ptr)
-      {
-         BOOST_ASSERT(ptr != nullptr);
-
-         if (ptr->is_written()) {
-            return !ptr->req_->get_config().cancel_if_unresponded;
-         } else {
-            return !ptr->req_->get_config().cancel_on_connection_lost;
-         }
-      };
-
-      auto point = std::stable_partition(std::begin(reqs_), std::end(reqs_), cond);
-
-      auto const ret = std::distance(point, std::end(reqs_));
-
-      std::for_each(point, std::end(reqs_), [](auto const& ptr) {
-         ptr->stop();
-      });
-
-      reqs_.erase(point, std::end(reqs_));
-      std::for_each(std::begin(reqs_), std::end(reqs_), [](auto const& ptr) {
-         return ptr->reset_status();
-      });
-
-      return ret;
-   }
-
-   auto cancel_unwritten_requests() -> std::size_t
-   {
-      auto f = [](auto const& ptr)
-      {
-         BOOST_ASSERT(ptr != nullptr);
-         return ptr->is_written();
-      };
-
-      auto point = std::stable_partition(std::begin(reqs_), std::end(reqs_), f);
-
-      auto const ret = std::distance(point, std::end(reqs_));
-
-      std::for_each(point, std::end(reqs_), [](auto const& ptr) {
-         ptr->stop();
-      });
-
-      reqs_.erase(point, std::end(reqs_));
-      return ret;
-   }
-
-   void cancel_impl(operation op)
-   {
-      switch (op) {
-         case operation::exec:
-         {
-            cancel_unwritten_requests();
-         } break;
-         case operation::run:
-         {
-            close();
-            writer_timer_.cancel();
-            receive_channel_.cancel();
-            cancel_on_conn_lost();
-         } break;
-         case operation::receive:
-         {
-            receive_channel_.cancel();
-         } break;
-         default: /* ignore */;
-      }
-   }
-
-   void on_write()
-   {
-      // We have to clear the payload right after writing it to use it
-      // as a flag that informs there is no ongoing write.
-      write_buffer_.clear();
-
-      // Notice this must come before the for-each below.
-      cancel_push_requests();
-
-      // There is small optimization possible here: traverse only the
-      // partition of unwritten requests instead of them all.
-      std::for_each(std::begin(reqs_), std::end(reqs_), [](auto const& ptr) {
-         BOOST_ASSERT_MSG(ptr != nullptr, "Expects non-null pointer.");
-         if (ptr->is_staged())
-            ptr->mark_written();
-      });
-   }
-
-   struct req_info {
-   public:
-      using node_type = resp3::basic_node<std::string_view>;
-      using wrapped_adapter_type = std::function<void(node_type const&, system::error_code&)>;
-
-      enum class action
-      {
-         stop,
-         proceed,
-         none,
-      };
-
-      explicit req_info(request const& req, adapter_type adapter, executor_type ex)
-      : timer_{ex}
-      , action_{action::none}
-      , req_{&req}
-      , adapter_{}
-      , expected_responses_{req.get_expected_responses()}
-      , status_{status::none}
-      , ec_{{}}
-      , read_size_{0}
-      {
-         timer_.expires_at((std::chrono::steady_clock::time_point::max)());
-
-         adapter_ = [this, adapter](node_type const& nd, system::error_code& ec)
-         {
-            auto const i = req_->get_expected_responses() - expected_responses_;
-            adapter(i, nd, ec);
-         };
-      }
-
-      auto proceed()
-      {
-         timer_.cancel();
-         action_ = action::proceed;
-      }
-
-      void stop()
-      {
-         timer_.cancel();
-         action_ = action::stop;
-      }
-
-      [[nodiscard]] auto is_waiting_write() const noexcept
-         { return !is_written() && !is_staged(); }
-
-      [[nodiscard]] auto is_written() const noexcept
-         { return status_ == status::written; }
-
-      [[nodiscard]] auto is_staged() const noexcept
-         { return status_ == status::staged; }
-
-      void mark_written() noexcept
-         { status_ = status::written; }
-
-      void mark_staged() noexcept
-         { status_ = status::staged; }
-
-      void reset_status() noexcept
-         { status_ = status::none; }
-
-      [[nodiscard]] auto stop_requested() const noexcept
-         { return action_ == action::stop;}
-
-      template <class CompletionToken>
-      auto async_wait(CompletionToken token)
-      {
-         return timer_.async_wait(std::move(token));
-      }
-
-   //private:
-      enum class status
-      { none
-      , staged
-      , written
-      };
-
-      timer_type timer_;
-      action action_;
-      request const* req_;
-      wrapped_adapter_type adapter_;
-
-      // Contains the number of commands that haven't been read yet.
-      std::size_t expected_responses_;
-      status status_;
-
-      system::error_code ec_;
-      std::size_t read_size_;
-   };
-
-   void remove_request(std::shared_ptr<req_info> const& info)
-   {
-      reqs_.erase(std::remove(std::begin(reqs_), std::end(reqs_), info));
-   }
-
-   using reqs_type = std::deque<std::shared_ptr<req_info>>;
-
-   template <class, class> friend struct reader_op;
-   template <class, class> friend struct writer_op;
-   template <class, class> friend struct run_op;
-   template <class> friend struct exec_op;
-   template <class, class, class> friend struct run_all_op;
-
-   void cancel_push_requests()
-   {
-      auto point = std::stable_partition(std::begin(reqs_), std::end(reqs_), [](auto const& ptr) {
-         return !(ptr->is_staged() && ptr->req_->get_expected_responses() == 0);
-      });
-
-      std::for_each(point, std::end(reqs_), [](auto const& ptr) {
-         ptr->proceed();
-      });
-
-      reqs_.erase(point, std::end(reqs_));
-   }
-
-   [[nodiscard]] bool is_writing() const noexcept
-   {
-      return !write_buffer_.empty();
-   }
-
-   void add_request_info(std::shared_ptr<req_info> const& info)
-   {
-      reqs_.push_back(info);
-
-      if (info->req_->has_hello_priority()) {
-         auto rend = std::partition_point(std::rbegin(reqs_), std::rend(reqs_), [](auto const& e) {
-               return e->is_waiting_write();
-         });
-
-         std::rotate(std::rbegin(reqs_), std::rbegin(reqs_) + 1, rend);
-      }
-
-      if (is_open() && !is_writing())
-         writer_timer_.cancel();
-   }
-
-   template <class CompletionToken, class Logger>
-   auto reader(Logger l, CompletionToken&& token)
-   {
-      return asio::async_compose
-         < CompletionToken
-         , void(system::error_code)
-         >(reader_op<this_type, Logger>{this, l}, token, writer_timer_);
-   }
-
-   template <class CompletionToken, class Logger>
-   auto writer(Logger l, CompletionToken&& token)
-   {
-      return asio::async_compose
-         < CompletionToken
-         , void(system::error_code)
-         >(writer_op<this_type, Logger>{this, l}, token, writer_timer_);
-   }
-
-   template <class Logger, class CompletionToken>
-   auto async_run_lean(config const& cfg, Logger l, CompletionToken token)
-   {
-      runner_.set_config(cfg);
-      l.set_prefix(runner_.get_config().log_prefix);
-      return asio::async_compose
-         < CompletionToken
-         , void(system::error_code)
-         >(run_op<this_type, Logger>{this, l}, token, writer_timer_);
-   }
-
-   [[nodiscard]] bool coalesce_requests()
-   {
-      // Coalesces the requests and marks them staged. After a
-      // successful write staged requests will be marked as written.
-      auto const point = std::partition_point(std::cbegin(reqs_), std::cend(reqs_), [](auto const& ri) {
-            return !ri->is_waiting_write();
-      });
-
-      std::for_each(point, std::cend(reqs_), [this](auto const& ri) {
-         // Stage the request.
-         write_buffer_ += ri->req_->payload();
-         ri->mark_staged();
-         usage_.commands_sent += ri->expected_responses_;
-      });
-
-      usage_.bytes_sent += std::size(write_buffer_);
-
-      return point != std::cend(reqs_);
-   }
-
-   bool is_waiting_response() const noexcept
-   {
-      return !std::empty(reqs_) && reqs_.front()->is_written();
-   }
-
-   void close()
-   {
-      if (stream_->next_layer().is_open()) {
-         system::error_code ec;
-         stream_->next_layer().close(ec);
-      }
-   }
-
-   auto is_open() const noexcept { return stream_->next_layer().is_open(); }
-   auto& lowest_layer() noexcept { return stream_->lowest_layer(); }
-
-   auto is_next_push()
-   {
-      // We handle unsolicited events in the following way
-      //
-      // 1. Its resp3 type is a push.
-      //
-      // 2. A non-push type is received with an empty requests
-      //    queue. I have noticed this is possible (e.g. -MISCONF).
-      //    I expect them to have type push so we can distinguish
-      //    them from responses to commands, but it is a
-      //    simple-error. If we are lucky enough to receive them
-      //    when the command queue is empty we can treat them as
-      //    server pushes, otherwise it is impossible to handle
-      //    them properly
-      //
-      // 3. The request does not expect any response but we got
-      //    one. This may happen if for example, subscribe with
-      //    wrong syntax.
-      //
-      // Useful links:
-      //
-      // - https://github.com/redis/redis/issues/11784
-      // - https://github.com/redis/redis/issues/6426
-      //
-
-      BOOST_ASSERT(!read_buffer_.empty());
-
-      return
-         (resp3::to_type(read_buffer_.front()) == resp3::type::push)
-          || reqs_.empty()
-          || (!reqs_.empty() && reqs_.front()->expected_responses_ == 0)
-          || !is_waiting_response(); // Added to deal with MONITOR.
-   }
-
-   auto get_suggested_buffer_growth() const noexcept
-   {
-      return parser_.get_suggested_buffer_growth(4096);
-   }
-
-   enum class parse_result { needs_more, push, resp };
-
-   using parse_ret_type = std::pair<parse_result, std::size_t>;
-
-   parse_ret_type on_finish_parsing(parse_result t)
-   {
-      if (t == parse_result::push) {
-         usage_.pushes_received += 1;
-         usage_.push_bytes_received += parser_.get_consumed();
-      } else {
-         usage_.responses_received += 1;
-         usage_.response_bytes_received += parser_.get_consumed();
-      }
-
-      on_push_ = false;
-      dbuf_.consume(parser_.get_consumed());
-      auto const res = std::make_pair(t, parser_.get_consumed());
-      parser_.reset();
-      return res;
-   }
-
-   parse_ret_type on_read(std::string_view data, system::error_code& ec)
-   {
-      // We arrive here in two states:
-      //
-      //    1. While we are parsing a message. In this case we
-      //       don't want to determine the type of the message in the
-      //       buffer (i.e. response vs push) but leave it untouched
-      //       until the parsing of a complete message ends.
-      //
-      //    2. On a new message, in which case we have to determine
-      //       whether the next messag is a push or a response.
-      //
-      if (!on_push_) // Prepare for new message.
-         on_push_ = is_next_push();
-
-      if (on_push_) {
-         if (!resp3::parse(parser_, data, receive_adapter_, ec))
-            return std::make_pair(parse_result::needs_more, 0);
-
-         if (ec)
-            return std::make_pair(parse_result::push, 0);
-
-         return on_finish_parsing(parse_result::push);
-      }
-
-      BOOST_ASSERT_MSG(is_waiting_response(), "Not waiting for a response (using MONITOR command perhaps?)");
-      BOOST_ASSERT(!reqs_.empty());
-      BOOST_ASSERT(reqs_.front() != nullptr);
-      BOOST_ASSERT(reqs_.front()->expected_responses_ != 0);
-
-      if (!resp3::parse(parser_, data, reqs_.front()->adapter_, ec))
-         return std::make_pair(parse_result::needs_more, 0);
-
-      if (ec) {
-         reqs_.front()->ec_ = ec;
-         reqs_.front()->proceed();
-         return std::make_pair(parse_result::resp, 0);
-      }
-
-      reqs_.front()->read_size_ += parser_.get_consumed();
-
-      if (--reqs_.front()->expected_responses_ == 0) {
-         // Done with this request.
-         reqs_.front()->proceed();
-         reqs_.pop_front();
-      }
-
-      return on_finish_parsing(parse_result::resp);
-   }
-
-   void reset()
-   {
-      write_buffer_.clear();
-      read_buffer_.clear();
-      parser_.reset();
-      on_push_ = false;
-   }
-
-   asio::ssl::context ctx_;
-   std::unique_ptr<next_layer_type> stream_;
-
-   // Notice we use a timer to simulate a condition-variable. It is
-   // also more suitable than a channel and the notify operation does
-   // not suspend.
-   timer_type writer_timer_;
-   receive_channel_type receive_channel_;
-   runner_type runner_;
-   receiver_adapter_type receive_adapter_;
-
-   using dyn_buffer_type = asio::dynamic_string_buffer<char, std::char_traits<char>, std::allocator<char>>;
-
-   std::string read_buffer_;
-   dyn_buffer_type dbuf_;
-   std::string write_buffer_;
-   reqs_type reqs_;
-   resp3::parser parser_{};
-   bool on_push_ = false;
-
-   usage usage_;
-};
-
-} // boost::redis::detail
-
-#endif // BOOST_REDIS_CONNECTION_BASE_HPP

include/boost/redis/detail/connection_state.hpp

@@ -0,0 +1,64 @@
+//
+// Copyright (c) 2025 Marcelo Zimbres Silva (mzimbres@gmail.com),
+// Ruben Perez Hidalgo (rubenperez038 at gmail dot com)
+//
+// Distributed under the Boost Software License, Version 1.0. (See accompanying
+// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+//
+
+#ifndef BOOST_REDIS_CONNECTION_STATE_HPP
+#define BOOST_REDIS_CONNECTION_STATE_HPP
+
+#include <boost/redis/config.hpp>
+#include <boost/redis/detail/multiplexer.hpp>
+#include <boost/redis/detail/subscription_tracker.hpp>
+#include <boost/redis/logger.hpp>
+#include <boost/redis/request.hpp>
+#include <boost/redis/resp3/node.hpp>
+#include <boost/redis/response.hpp>
+
+#include <random>
+#include <string>
+#include <vector>
+
+namespace boost::redis::detail {
+
+// A random engine that gets seeded lazily.
+// Seeding with std::random_device is not trivial and might fail.
+class lazy_random_engine {
+   bool seeded_{};
+   std::minstd_rand eng_;
+
+public:
+   lazy_random_engine() = default;
+   std::minstd_rand& get()
+   {
+      if (!seeded_) {
+         eng_.seed(static_cast<std::minstd_rand::result_type>(std::random_device{}()));
+         seeded_ = true;
+      }
+      return eng_;
+   }
+};
+
+// Contains all the members in connection that don't depend on the Executor.
+// Makes implementing sans-io algorithms easier
+struct connection_state {
+   buffered_logger logger;
+   config cfg{};
+   multiplexer mpx{};
+   std::string diagnostic{};  // Used by the setup request and Sentinel
+   request setup_req{};
+   request ping_req{};
+   subscription_tracker tracker{};
+   bool receive2_running{false}, receive2_cancelled{false};
+
+   // Sentinel stuff
+   lazy_random_engine eng{};
+   std::vector<address> sentinels{};
+   std::vector<resp3::node> sentinel_resp_nodes{};  // for parsing
+};
+
+}  // namespace boost::redis::detail
+
+#endif  // BOOST_REDIS_CONNECTOR_HPP

include/boost/redis/detail/connector.hpp

@@ -1,133 +0,0 @@
-/* Copyright (c) 2018-2023 Marcelo Zimbres Silva (mzimbres@gmail.com)
- *
- * Distributed under the Boost Software License, Version 1.0. (See
- * accompanying file LICENSE.txt)
- */
-
-#ifndef BOOST_REDIS_CONNECTOR_HPP
-#define BOOST_REDIS_CONNECTOR_HPP
-
-#include <boost/redis/detail/helper.hpp>
-#include <boost/redis/error.hpp>
-#include <boost/asio/compose.hpp>
-#include <boost/asio/connect.hpp>
-#include <boost/asio/coroutine.hpp>
-#include <boost/asio/experimental/parallel_group.hpp>
-#include <boost/asio/ip/tcp.hpp>
-#include <boost/asio/steady_timer.hpp>
-#include <string>
-#include <chrono>
-
-namespace boost::redis::detail
-{
-
-template <class Connector, class Stream>
-struct connect_op {
-   Connector* ctor_ = nullptr;
-   Stream* stream = nullptr;
-   asio::ip::tcp::resolver::results_type const* res_ = nullptr;
-   asio::coroutine coro{};
-
-   template <class Self>
-   void operator()( Self& self
-                  , std::array<std::size_t, 2> const& order = {}
-                  , system::error_code const& ec1 = {}
-                  , asio::ip::tcp::endpoint const& ep= {}
-                  , system::error_code const& ec2 = {})
-   {
-      BOOST_ASIO_CORO_REENTER (coro)
-      {
-         ctor_->timer_.expires_after(ctor_->timeout_);
-
-         BOOST_ASIO_CORO_YIELD
-         asio::experimental::make_parallel_group(
-            [this](auto token)
-            {
-               auto f = [](system::error_code const&, auto const&) { return true; };
-               return asio::async_connect(*stream, *res_, f, token);
-            },
-            [this](auto token) { return ctor_->timer_.async_wait(token);}
-         ).async_wait(
-            asio::experimental::wait_for_one(),
-            std::move(self));
-
-         if (is_cancelled(self)) {
-            self.complete(asio::error::operation_aborted);
-            return;
-         }
-
-         switch (order[0]) {
-            case 0: {
-               ctor_->endpoint_ = ep;
-               self.complete(ec1);
-            } break;
-            case 1:
-            {
-               if (ec2) {
-                  self.complete(ec2);
-               } else {
-                  self.complete(error::connect_timeout);
-               }
-            } break;
-
-            default: BOOST_ASSERT(false);
-         }
-      }
-   }
-};
-
-template <class Executor>
-class connector {
-public:
-   using timer_type =
-      asio::basic_waitable_timer<
-         std::chrono::steady_clock,
-         asio::wait_traits<std::chrono::steady_clock>,
-         Executor>;
-
-   connector(Executor ex)
-   : timer_{ex}
-   {}
-
-   void set_config(config const& cfg)
-      { timeout_ = cfg.connect_timeout; }
-
-   template <class Stream, class CompletionToken>
-   auto
-   async_connect(
-         Stream& stream,
-         asio::ip::tcp::resolver::results_type const& res,
-         CompletionToken&& token)
-   {
-      return asio::async_compose
-         < CompletionToken
-         , void(system::error_code)
-         >(connect_op<connector, Stream>{this, &stream, &res}, token, timer_);
-   }
-
-   std::size_t cancel(operation op)
-   {
-      switch (op) {
-         case operation::connect:
-         case operation::all:
-            timer_.cancel();
-            break;
-         default: /* ignore */;
-      }
-
-      return 0;
-   }
-
-   auto const& endpoint() const noexcept { return endpoint_;}
-
-private:
-   template <class, class> friend struct connect_op;
-
-   timer_type timer_;
-   std::chrono::steady_clock::duration timeout_ = std::chrono::seconds{2};
-   asio::ip::tcp::endpoint endpoint_;
-};
-
-} // boost::redis::detail
-
-#endif // BOOST_REDIS_CONNECTOR_HPP

include/boost/redis/detail/coroutine.hpp

@@ -0,0 +1,36 @@
+//
+// Copyright (c) 2025 Marcelo Zimbres Silva (mzimbres@gmail.com),
+// Ruben Perez Hidalgo (rubenperez038 at gmail dot com)
+//
+// Distributed under the Boost Software License, Version 1.0. (See accompanying
+// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+//
+
+#ifndef BOOST_REDIS_DETAIL_COROUTINE_HPP
+#define BOOST_REDIS_DETAIL_COROUTINE_HPP
+
+// asio::coroutine uses __COUNTER__ internally, which can trigger
+// ODR violations if we use them in header-only code. These manifest as
+// extremely hard-to-debug bugs only present in release builds.
+// Use this instead when doing coroutines in non-template code.
+// Adapted from Boost.MySQL.
+
+// Coroutine state is represented as an integer (resume_point_var).
+// Every yield gets assigned a unique value (resume_point_id).
+// Yielding sets the next resume point, returns, and sets a case label for re-entering.
+// Coroutines need to switch on resume_point_var to re-enter.
+
+// Enclosing this in a scope allows placing the macro inside a brace-less for/while loop
+// The empty scope after the case label is required because labels can't be at the end of a compound statement
+#define BOOST_REDIS_YIELD(resume_point_var, resume_point_id, ...) \
+   {                                                              \
+      resume_point_var = resume_point_id;                         \
+      return {__VA_ARGS__};                                       \
+      case resume_point_id:                                       \
+      {                                                           \
+      }                                                           \
+   }
+
+#define BOOST_REDIS_CORO_INITIAL case 0:
+
+#endif

include/boost/redis/detail/exec_fsm.hpp

@@ -0,0 +1,74 @@
+//
+// Copyright (c) 2025 Marcelo Zimbres Silva (mzimbres@gmail.com),
+// Ruben Perez Hidalgo (rubenperez038 at gmail dot com)
+//
+// Distributed under the Boost Software License, Version 1.0. (See accompanying
+// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+//
+
+#ifndef BOOST_REDIS_EXEC_FSM_HPP
+#define BOOST_REDIS_EXEC_FSM_HPP
+
+#include <boost/redis/detail/multiplexer.hpp>
+
+#include <boost/asio/cancellation_type.hpp>
+#include <boost/system/error_code.hpp>
+
+#include <cstddef>
+#include <memory>
+
+// Sans-io algorithm for async_exec, as a finite state machine
+
+namespace boost::redis::detail {
+
+struct connection_state;
+
+// What should we do next?
+enum class exec_action_type
+{
+   setup_cancellation,  // Set up the cancellation types supported by the composed operation
+   immediate,           // Invoke asio::async_immediate to avoid re-entrancy problems
+   done,                // Call the final handler
+   notify_writer,       // Notify the writer task
+   wait_for_response,   // Wait to be notified
+};
+
+class exec_action {
+   exec_action_type type_;
+   system::error_code ec_;
+   std::size_t bytes_read_;
+
+public:
+   exec_action(exec_action_type type) noexcept
+   : type_{type}
+   { }
+
+   exec_action(system::error_code ec, std::size_t bytes_read = 0u) noexcept
+   : type_{exec_action_type::done}
+   , ec_{ec}
+   , bytes_read_{bytes_read}
+   { }
+
+   exec_action_type type() const { return type_; }
+   system::error_code error() const { return ec_; }
+   std::size_t bytes_read() const { return bytes_read_; }
+};
+
+class exec_fsm {
+   int resume_point_{0};
+   std::shared_ptr<multiplexer::elem> elem_;
+
+public:
+   exec_fsm(std::shared_ptr<multiplexer::elem> elem) noexcept
+   : elem_(std::move(elem))
+   { }
+
+   exec_action resume(
+      bool connection_is_open,
+      connection_state& st,
+      asio::cancellation_type_t cancel_state);
+};
+
+}  // namespace boost::redis::detail
+
+#endif  // BOOST_REDIS_CONNECTOR_HPP

include/boost/redis/detail/exec_one_fsm.hpp

@@ -0,0 +1,69 @@
+//
+// Copyright (c) 2025 Marcelo Zimbres Silva (mzimbres@gmail.com),
+// Ruben Perez Hidalgo (rubenperez038 at gmail dot com)
+//
+// Distributed under the Boost Software License, Version 1.0. (See accompanying
+// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+//
+
+#ifndef BOOST_REDIS_EXEC_ONE_FSM_HPP
+#define BOOST_REDIS_EXEC_ONE_FSM_HPP
+
+#include <boost/redis/adapter/any_adapter.hpp>
+#include <boost/redis/resp3/parser.hpp>
+
+#include <boost/asio/cancellation_type.hpp>
+#include <boost/system/error_code.hpp>
+
+#include <cstddef>
+
+// Sans-io algorithm for async_exec_one, as a finite state machine
+
+namespace boost::redis::detail {
+
+class read_buffer;
+
+// What should we do next?
+enum class exec_one_action_type
+{
+   done,       // Call the final handler
+   write,      // Write the request
+   read_some,  // Read into the read buffer
+};
+
+struct exec_one_action {
+   exec_one_action_type type;
+   system::error_code ec;
+
+   exec_one_action(exec_one_action_type type) noexcept
+   : type{type}
+   { }
+
+   exec_one_action(system::error_code ec) noexcept
+   : type{exec_one_action_type::done}
+   , ec{ec}
+   { }
+};
+
+class exec_one_fsm {
+   int resume_point_{0};
+   any_adapter adapter_;
+   std::size_t remaining_responses_;
+   resp3::parser parser_;
+
+public:
+   exec_one_fsm(any_adapter resp, std::size_t expected_responses)
+   : adapter_(std::move(resp))
+   , remaining_responses_(expected_responses)
+   { }
+
+   exec_one_action resume(
+      read_buffer& buffer,
+      system::error_code ec,
+      std::size_t bytes_transferred,
+      asio::cancellation_type_t cancel_state);
+};
+
+}  // namespace boost::redis::detail
+
+#endif  // BOOST_REDIS_CONNECTOR_HPP

include/boost/redis/detail/handshaker.hpp

@@ -1,124 +0,0 @@
-/* Copyright (c) 2018-2023 Marcelo Zimbres Silva (mzimbres@gmail.com)
- *
- * Distributed under the Boost Software License, Version 1.0. (See
- * accompanying file LICENSE.txt)
- */
-
-#ifndef BOOST_REDIS_SSL_CONNECTOR_HPP
-#define BOOST_REDIS_SSL_CONNECTOR_HPP
-
-#include <boost/redis/detail/helper.hpp>
-#include <boost/redis/error.hpp>
-#include <boost/asio/compose.hpp>
-#include <boost/asio/connect.hpp>
-#include <boost/asio/coroutine.hpp>
-#include <boost/asio/experimental/parallel_group.hpp>
-#include <boost/asio/ip/tcp.hpp>
-#include <boost/asio/steady_timer.hpp>
-#include <boost/asio/ssl.hpp>
-#include <string>
-#include <chrono>
-
-namespace boost::redis::detail
-{
-
-template <class Handshaker, class Stream>
-struct handshake_op {
-   Handshaker* hsher_ = nullptr;
-   Stream* stream_ = nullptr;
-   asio::coroutine coro{};
-
-   template <class Self>
-   void operator()( Self& self
-                  , std::array<std::size_t, 2> const& order = {}
-                  , system::error_code const& ec1 = {}
-                  , system::error_code const& ec2 = {})
-   {
-      BOOST_ASIO_CORO_REENTER (coro)
-      {
-         hsher_->timer_.expires_after(hsher_->timeout_);
-
-         BOOST_ASIO_CORO_YIELD
-         asio::experimental::make_parallel_group(
-            [this](auto token) { return stream_->async_handshake(asio::ssl::stream_base::client, token); },
-            [this](auto token) { return hsher_->timer_.async_wait(token);}
-         ).async_wait(
-            asio::experimental::wait_for_one(),
-            std::move(self));
-
-         if (is_cancelled(self)) {
-            self.complete(asio::error::operation_aborted);
-            return;
-         }
-
-         switch (order[0]) {
-            case 0: {
-               self.complete(ec1);
-            } break;
-            case 1:
-            {
-               if (ec2) {
-                  self.complete(ec2);
-               } else {
-                  self.complete(error::ssl_handshake_timeout);
-               }
-            } break;
-
-            default: BOOST_ASSERT(false);
-         }
-      }
-   }
-};
-
-template <class Executor>
-class handshaker {
-public:
-   using timer_type =
-      asio::basic_waitable_timer<
-         std::chrono::steady_clock,
-         asio::wait_traits<std::chrono::steady_clock>,
-         Executor>;
-
-   handshaker(Executor ex)
-   : timer_{ex}
-   {}
-
-   template <class Stream, class CompletionToken>
-   auto
-   async_handshake(Stream& stream, CompletionToken&& token)
-   {
-      return asio::async_compose
-         < CompletionToken
-         , void(system::error_code)
-         >(handshake_op<handshaker, Stream>{this, &stream}, token, timer_);
-   }
-
-   std::size_t cancel(operation op)
-   {
-      switch (op) {
-         case operation::ssl_handshake:
-         case operation::all:
-            timer_.cancel();
-            break;
-         default: /* ignore */;
-      }
-
-      return 0;
-   }
-
-   constexpr bool is_dummy() const noexcept
-      {return false;}
-
-   void set_config(config const& cfg)
-      { timeout_ = cfg.ssl_handshake_timeout; }
-
-private:
-   template <class, class> friend struct handshake_op;
-
-   timer_type timer_;
-   std::chrono::steady_clock::duration timeout_;
-};
-
-} // boost::redis::detail
-
-#endif // BOOST_REDIS_SSL_CONNECTOR_HPP

include/boost/redis/detail/health_checker.hpp

@@ -1,252 +0,0 @@
-/* Copyright (c) 2018-2023 Marcelo Zimbres Silva (mzimbres@gmail.com)
- *
- * Distributed under the Boost Software License, Version 1.0. (See
- * accompanying file LICENSE.txt)
- */
-
-#ifndef BOOST_REDIS_HEALTH_CHECKER_HPP
-#define BOOST_REDIS_HEALTH_CHECKER_HPP
-
-// Has to included before promise.hpp to build on msvc.
-#include <boost/redis/request.hpp>
-#include <boost/redis/response.hpp>
-#include <boost/redis/operation.hpp>
-#include <boost/redis/detail/helper.hpp>
-#include <boost/redis/config.hpp>
-#include <boost/asio/steady_timer.hpp>
-#include <boost/asio/compose.hpp>
-#include <boost/asio/consign.hpp>
-#include <boost/asio/coroutine.hpp>
-#include <boost/asio/post.hpp>
-#include <boost/asio/experimental/parallel_group.hpp>
-#include <memory>
-#include <chrono>
-
-namespace boost::redis::detail {
-
-template <class HealthChecker, class Connection, class Logger>
-class ping_op {
-public:
-   HealthChecker* checker_ = nullptr;
-   Connection* conn_ = nullptr;
-   Logger logger_;
-   asio::coroutine coro_{};
-
-   template <class Self>
-   void operator()(Self& self, system::error_code ec = {}, std::size_t = 0)
-   {
-      BOOST_ASIO_CORO_REENTER (coro_) for (;;)
-      {
-         if (checker_->checker_has_exited_) {
-            logger_.trace("ping_op: checker has exited. Exiting ...");
-            self.complete({});
-            return;
-         }
-
-         BOOST_ASIO_CORO_YIELD
-         conn_->async_exec(checker_->req_, checker_->resp_, std::move(self));
-         if (ec || is_cancelled(self)) {
-            logger_.trace("ping_op: error/cancelled (1).");
-            checker_->wait_timer_.cancel();
-            self.complete(!!ec ? ec : asio::error::operation_aborted);
-            return;
-         }
-
-         // Wait before pinging again.
-         checker_->ping_timer_.expires_after(checker_->ping_interval_);
-         BOOST_ASIO_CORO_YIELD
-         checker_->ping_timer_.async_wait(std::move(self));
-         if (ec || is_cancelled(self)) {
-            logger_.trace("ping_op: error/cancelled (2).");
-            self.complete(!!ec ? ec : asio::error::operation_aborted);
-            return;
-         }
-      }
-   }
-};
-
-template <class HealthChecker, class Connection, class Logger>
-class check_timeout_op {
-public:
-   HealthChecker* checker_ = nullptr;
-   Connection* conn_ = nullptr;
-   Logger logger_;
-   asio::coroutine coro_{};
-
-   template <class Self>
-   void operator()(Self& self, system::error_code ec = {})
-   {
-      BOOST_ASIO_CORO_REENTER (coro_) for (;;)
-      {
-         checker_->wait_timer_.expires_after(2 * checker_->ping_interval_);
-         BOOST_ASIO_CORO_YIELD
-         checker_->wait_timer_.async_wait(std::move(self));
-         if (ec || is_cancelled(self)) {
-            logger_.trace("check-timeout-op: error/canceled. Exiting ...");
-            self.complete(!!ec ? ec : asio::error::operation_aborted);
-            return;
-         }
-
-         if (checker_->resp_.has_error()) {
-            logger_.trace("check-timeout-op: Response error. Exiting ...");
-            self.complete({});
-            return;
-         }
-
-         if (checker_->resp_.value().empty()) {
-            logger_.trace("check-timeout-op: Response has no value. Exiting ...");
-            checker_->ping_timer_.cancel();
-            conn_->cancel(operation::run);
-            checker_->checker_has_exited_ = true;
-            self.complete(error::pong_timeout);
-            return;
-         }
-
-         if (checker_->resp_.has_value()) {
-            checker_->resp_.value().clear();
-         }
-      }
-   }
-};
-
-template <class HealthChecker, class Connection, class Logger>
-class check_health_op {
-public:
-   HealthChecker* checker_ = nullptr;
-   Connection* conn_ = nullptr;
-   Logger logger_;
-   asio::coroutine coro_{};
-
-   template <class Self>
-   void
-   operator()(
-         Self& self,
-         std::array<std::size_t, 2> order = {},
-         system::error_code ec1 = {},
-         system::error_code ec2 = {})
-   {
-      BOOST_ASIO_CORO_REENTER (coro_)
-      {
-         if (checker_->ping_interval_ == std::chrono::seconds::zero()) {
-            logger_.trace("check-health-op: timeout disabled.");
-            BOOST_ASIO_CORO_YIELD
-            asio::post(std::move(self));
-            self.complete({});
-            return;
-         }
-
-         BOOST_ASIO_CORO_YIELD
-         asio::experimental::make_parallel_group(
-            [this](auto token) { return checker_->async_ping(*conn_, logger_, token); },
-            [this](auto token) { return checker_->async_check_timeout(*conn_, logger_, token);}
-         ).async_wait(
-            asio::experimental::wait_for_one(),
-            std::move(self));
-
-         logger_.on_check_health(ec1, ec2);
-
-         if (is_cancelled(self)) {
-            logger_.trace("check-health-op: canceled. Exiting ...");
-            self.complete(asio::error::operation_aborted);
-            return;
-         }
-
-         switch (order[0]) {
-            case 0: self.complete(ec1); return;
-            case 1: self.complete(ec2); return;
-            default: BOOST_ASSERT(false);
-         }
-      }
-   }
-};
-
-template <class Executor>
-class health_checker {
-private:
-   using timer_type =
-      asio::basic_waitable_timer<
-         std::chrono::steady_clock,
-         asio::wait_traits<std::chrono::steady_clock>,
-         Executor>;
-
-public:
-   health_checker(Executor ex)
-   : ping_timer_{ex}
-   , wait_timer_{ex}
-   {
-      req_.push("PING", "Boost.Redis");
-   }
-
-   void set_config(config const& cfg)
-   {
-      req_.clear();
-      req_.push("PING", cfg.health_check_id);
-      ping_interval_ = cfg.health_check_interval;
-   }
-
-   template <
-      class Connection,
-      class Logger,
-      class CompletionToken = asio::default_completion_token_t<Executor>
-   >
-   auto
-   async_check_health(
-      Connection& conn,
-      Logger l,
-      CompletionToken token = CompletionToken{})
-   {
-      checker_has_exited_ = false;
-      return asio::async_compose
-         < CompletionToken
-         , void(system::error_code)
-         >(check_health_op<health_checker, Connection, Logger>{this, &conn, l}, token, conn);
-   }
-
-   std::size_t cancel(operation op)
-   {
-      switch (op) {
-         case operation::health_check:
-         case operation::all:
-            ping_timer_.cancel();
-            wait_timer_.cancel();
-            break;
-         default: /* ignore */;
-      }
-
-      return 0;
-   }
-
-private:
-   template <class Connection, class Logger, class CompletionToken>
-   auto async_ping(Connection& conn, Logger l, CompletionToken token)
-   {
-      return asio::async_compose
-         < CompletionToken
-         , void(system::error_code)
-         >(ping_op<health_checker, Connection, Logger>{this, &conn, l}, token, conn, ping_timer_);
-   }
-
-   template <class Connection, class Logger, class CompletionToken>
-   auto async_check_timeout(Connection& conn, Logger l, CompletionToken token)
-   {
-      return asio::async_compose
-         < CompletionToken
-         , void(system::error_code)
-         >(check_timeout_op<health_checker, Connection, Logger>{this, &conn, l}, token, conn, wait_timer_);
-   }
-
-   template <class, class, class> friend class ping_op;
-   template <class, class, class> friend class check_timeout_op;
-   template <class, class, class> friend class check_health_op;
-
-   timer_type ping_timer_;
-   timer_type wait_timer_;
-   redis::request req_;
-   redis::generic_response resp_;
-   std::chrono::steady_clock::duration ping_interval_ = std::chrono::seconds{5};
-   bool checker_has_exited_ = false;
-};
-
-} // boost::redis::detail
-
-#endif // BOOST_REDIS_HEALTH_CHECKER_HPP

include/boost/redis/detail/helper.hpp

@@ -1,37 +0,0 @@
-/* Copyright (c) 2018-2023 Marcelo Zimbres Silva (mzimbres@gmail.com)
- *
- * Distributed under the Boost Software License, Version 1.0. (See
- * accompanying file LICENSE.txt)
- */
-
-#ifndef BOOST_REDIS_HELPER_HPP
-#define BOOST_REDIS_HELPER_HPP
-
-#include <boost/asio/cancellation_type.hpp>
-
-namespace boost::redis::detail
-{
-
-template <class T>
-auto is_cancelled(T const& self)
-{
-   return self.get_cancellation_state().cancelled() != asio::cancellation_type_t::none;
-}
-
-#define BOOST_REDIS_CHECK_OP0(X)\
-   if (ec || redis::detail::is_cancelled(self)) {\
-      X\
-      self.complete(!!ec ? ec : asio::error::operation_aborted);\
-      return;\
-   }
-
-#define BOOST_REDIS_CHECK_OP1(X)\
-   if (ec || redis::detail::is_cancelled(self)) {\
-      X\
-      self.complete(!!ec ? ec : asio::error::operation_aborted, {});\
-      return;\
-   }
-
-} // boost::redis::detail
-
-#endif // BOOST_REDIS_HELPER_HPP

include/boost/redis/detail/multiplexer.hpp

@@ -0,0 +1,239 @@
+/* Copyright (c) 2018-2025 Marcelo Zimbres Silva (mzimbres@gmail.com)
+ *
+ * Distributed under the Boost Software License, Version 1.0. (See
+ * accompanying file LICENSE.txt)
+ */
+
+#ifndef BOOST_REDIS_MULTIPLEXER_HPP
+#define BOOST_REDIS_MULTIPLEXER_HPP
+
+#include <boost/redis/adapter/adapt.hpp>
+#include <boost/redis/adapter/any_adapter.hpp>
+#include <boost/redis/config.hpp>
+#include <boost/redis/detail/read_buffer.hpp>
+#include <boost/redis/resp3/node.hpp>
+#include <boost/redis/resp3/parser.hpp>
+#include <boost/redis/resp3/type.hpp>
+#include <boost/redis/usage.hpp>
+
+#include <boost/system/error_code.hpp>
+
+#include <cstddef>
+#include <deque>
+#include <functional>
+#include <memory>
+#include <string_view>
+#include <utility>
+
+namespace boost::redis {
+
+class request;
+
+namespace detail {
+
+// Return type of the multiplexer::consume_next function
+enum class consume_result
+{
+   needs_more,    // consume_next didn't have enough data
+   got_response,  // got a response to a regular command, vs. a push
+   got_push,      // got a response to a push
+};
+
+class multiplexer {
+public:
+   struct elem {
+   public:
+      explicit elem(request const& req, any_adapter adapter);
+
+      void set_done_callback(std::function<void()> f) noexcept { done_ = std::move(f); };
+
+      auto notify_done() noexcept -> void
+      {
+         status_ = status::done;
+         done_();
+      }
+
+      auto notify_error(system::error_code ec) noexcept -> void;
+
+      [[nodiscard]]
+      auto is_waiting() const noexcept
+      {
+         return status_ == status::waiting;
+      }
+
+      [[nodiscard]]
+      auto is_written() const noexcept
+      {
+         return status_ == status::written;
+      }
+
+      [[nodiscard]]
+      auto is_staged() const noexcept
+      {
+         return status_ == status::staged;
+      }
+
+      [[nodiscard]]
+      bool is_done() const noexcept
+      {
+         return status_ == status::done;
+      }
+
+      void mark_written() noexcept { status_ = status::written; }
+
+      void mark_staged() noexcept { status_ = status::staged; }
+
+      void mark_waiting() noexcept { status_ = status::waiting; }
+
+      auto get_error() const -> system::error_code const& { return ec_; }
+
+      auto get_request() const -> request const& { return *req_; }
+
+      auto get_read_size() const -> std::size_t { return read_size_; }
+
+      auto get_remaining_responses() const -> std::size_t { return remaining_responses_; }
+
+      auto commit_response(std::size_t read_size) -> void;
+
+      auto get_adapter() -> any_adapter& { return adapter_; }
+
+      // Marks the element as an abandoned request. An abandoned request
+      // won't cause problems when its response arrives, but that response will be ignored.
+      void mark_abandoned();
+
+      [[nodiscard]]
+      bool is_abandoned() const
+      {
+         return !req_;
+      }
+
+   private:
+      enum class status
+      {
+         waiting,  // the request hasn't been written yet
+         staged,   // we've issued the write for this request, but it hasn't finished yet
+         written,  // the request has been written successfully
+         done,     // the request has completed and the done callback has been invoked
+      };
+
+      request const* req_;
+      any_adapter adapter_;
+      std::function<void()> done_;
+
+      // Contains the number of commands that haven't been read yet.
+      std::size_t remaining_responses_;
+      status status_;
+
+      system::error_code ec_;
+      std::size_t read_size_;
+   };
+
+   multiplexer();
+
+   // To be called before a write operation. Coalesces all available requests
+   // into a single buffer. Returns the number of coalesced requests.
+   // Must be called before cancel_on_conn_lost() because it might change
+   // request status.
+   [[nodiscard]]
+   auto prepare_write() -> std::size_t;
+
+   // To be called after a write operation.
+   // Returns true once all the bytes in the buffer generated by prepare_write
+   // have been written.
+   // Must be called before cancel_on_conn_lost() because it might change
+   // request status.
+   auto commit_write(std::size_t bytes_written) -> bool;
+
+   // To be called after a successful read operation.
+   // Must be called before cancel_on_conn_lost() because it might change
+   // request status.
+   [[nodiscard]]
+   auto consume(system::error_code& ec) -> std::pair<consume_result, std::size_t>;
+
+   auto add(std::shared_ptr<elem> const& ptr) -> void;
+   void cancel(std::shared_ptr<elem> const& ptr);
+   auto reset() -> void;
+
+   [[nodiscard]]
+   auto const& get_parser() const noexcept
+   {
+      return parser_;
+   }
+
+   auto cancel_waiting() -> std::size_t;
+
+   // To be called exactly once to clean up state after a connection becomes unhealthy.
+   // Requests are canceled or returned to the waiting state to be re-sent to the server,
+   // depending on their configuration. After this function is called, prepare_write,
+   // commit_write and consume_next must not be called until a reset() happens.
+   // Otherwise, race conditions like the following might happen
+   // (see https://github.com/boostorg/redis/pull/309 and https://github.com/boostorg/redis/issues/181):
+   //
+   //   - This function runs and cancels a request, then consume_next runs. It tries to access
+   //     a request and adapter that might have been destroyed.
+   //   - This function runs and returns a request to waiting, then prepare_write runs.
+   //     It incorrectly sets the request state to staged, causing de synchronization between requests and responses.
+   void cancel_on_conn_lost();
+
+   [[nodiscard]]
+   auto get_write_buffer() const noexcept -> std::string_view
+   {
+      return std::string_view{write_buffer_}.substr(write_offset_);
+   }
+
+   [[nodiscard]]
+   auto get_read_buffer() noexcept -> read_buffer&
+   {
+      return read_buffer_;
+   }
+
+   [[nodiscard]]
+   auto get_prepared_read_buffer() noexcept -> read_buffer::span_type;
+
+   [[nodiscard]]
+   auto prepare_read() noexcept -> system::error_code;
+
+   void commit_read(std::size_t read_size);
+
+   [[nodiscard]]
+   auto get_read_buffer_size() const noexcept -> std::size_t;
+
+   void set_receive_adapter(any_adapter adapter);
+
+   [[nodiscard]]
+   auto get_usage() const noexcept -> usage
+   {
+      return usage_;
+   }
+
+   void set_config(config const& cfg);
+
+private:
+   void commit_usage(bool is_push, read_buffer::consume_result res);
+
+   [[nodiscard]]
+   auto is_next_push(std::string_view data) const noexcept -> bool;
+
+   // Completes requests that don't expect a response
+   void release_push_requests();
+
+   [[nodiscard]]
+   consume_result consume_impl(system::error_code& ec);
+
+   read_buffer read_buffer_;
+   std::string write_buffer_;
+   std::size_t write_offset_{};  // how many bytes of the write buffer have been written?
+   std::deque<std::shared_ptr<elem>> reqs_;
+   resp3::parser parser_{};
+   bool on_push_ = false;
+   bool cancel_run_called_ = false;
+   usage usage_;
+   any_adapter receive_adapter_;
+};
+
+auto make_elem(request const& req, any_adapter adapter) -> std::shared_ptr<multiplexer::elem>;
+
+}  // namespace detail
+}  // namespace boost::redis
+
+#endif  // BOOST_REDIS_MULTIPLEXER_HPP

include/boost/redis/detail/read_buffer.hpp

@@ -0,0 +1,69 @@
+/* Copyright (c) 2018-2025 Marcelo Zimbres Silva (mzimbres@gmail.com)
+ *
+ * Distributed under the Boost Software License, Version 1.0. (See
+ * accompanying file LICENSE.txt)
+ */
+
+#ifndef BOOST_REDIS_READ_BUFFER_HPP
+#define BOOST_REDIS_READ_BUFFER_HPP
+
+#include <boost/core/span.hpp>
+#include <boost/system/error_code.hpp>
+
+#include <cstddef>
+#include <string_view>
+#include <utility>
+#include <vector>
+
+namespace boost::redis::detail {
+
+class read_buffer {
+public:
+   using span_type = span<char>;
+
+   struct consume_result {
+      std::size_t consumed;
+      std::size_t rotated;
+   };
+
+   // See config.hpp for the meaning of these parameters.
+   struct config {
+      std::size_t read_buffer_append_size = 4096u;
+      std::size_t max_read_size = static_cast<std::size_t>(-1);
+   };
+
+   // Prepare the buffer to receive more data.
+   [[nodiscard]]
+   auto prepare() -> system::error_code;
+
+   [[nodiscard]]
+   auto get_prepared() noexcept -> span_type;
+
+   void commit(std::size_t read_size);
+
+   [[nodiscard]]
+   auto get_commited() const noexcept -> std::string_view;
+
+   void clear();
+
+   // Consumes committed data by rotating the remaining data to the
+   // front of the buffer.
+   auto consume(std::size_t size) -> consume_result;
+
+   void reserve(std::size_t n);
+
+   friend bool operator==(read_buffer const& lhs, read_buffer const& rhs);
+
+   friend bool operator!=(read_buffer const& lhs, read_buffer const& rhs);
+
+   void set_config(config const& cfg) noexcept { cfg_ = cfg; };
+
+private:
+   config cfg_ = config{};
+   std::vector<char> buffer_;
+   std::size_t append_buf_begin_ = 0;
+};
+
+}  // namespace boost::redis::detail
+
+#endif  // BOOST_REDIS_READ_BUFFER_HPP

include/boost/redis/detail/reader_fsm.hpp

@@ -0,0 +1,97 @@
+/* Copyright (c) 2018-2025 Marcelo Zimbres Silva (mzimbres@gmail.com)
+ *
+ * Distributed under the Boost Software License, Version 1.0. (See
+ * accompanying file LICENSE.txt)
+ */
+
+#ifndef BOOST_REDIS_READER_FSM_HPP
+#define BOOST_REDIS_READER_FSM_HPP
+
+#include <boost/redis/detail/connection_state.hpp>
+#include <boost/redis/detail/multiplexer.hpp>
+
+#include <boost/asio/cancellation_type.hpp>
+#include <boost/system/error_code.hpp>
+
+#include <chrono>
+#include <cstddef>
+
+namespace boost::redis::detail {
+
+class read_buffer;
+
+class reader_fsm {
+public:
+   class action {
+   public:
+      enum class type
+      {
+         read_some,
+         notify_push_receiver,
+         done,
+      };
+
+      action(system::error_code ec) noexcept
+      : type_(type::done)
+      , ec_(ec)
+      { }
+
+      static action read_some(std::chrono::steady_clock::duration timeout) { return {timeout}; }
+
+      static action notify_push_receiver(std::size_t bytes) { return {bytes}; }
+
+      type get_type() const { return type_; }
+
+      system::error_code error() const
+      {
+         BOOST_ASSERT(type_ == type::done);
+         return ec_;
+      }
+
+      std::chrono::steady_clock::duration timeout() const
+      {
+         BOOST_ASSERT(type_ == type::read_some);
+         return timeout_;
+      }
+
+      std::size_t push_size() const
+      {
+         BOOST_ASSERT(type_ == type::notify_push_receiver);
+         return push_size_;
+      }
+
+   private:
+      action(std::size_t push_size) noexcept
+      : type_(type::notify_push_receiver)
+      , push_size_(push_size)
+      { }
+
+      action(std::chrono::steady_clock::duration t) noexcept
+      : type_(type::read_some)
+      , timeout_(t)
+      { }
+
+      type type_;
+      union {
+         system::error_code ec_;
+         std::chrono::steady_clock::duration timeout_;
+         std::size_t push_size_{};
+      };
+   };
+
+   action resume(
+      connection_state& st,
+      std::size_t bytes_read,
+      system::error_code ec,
+      asio::cancellation_type_t cancel_state);
+
+   reader_fsm() = default;
+
+private:
+   int resume_point_{0};
+   std::pair<consume_result, std::size_t> res_{consume_result::needs_more, 0u};
+};
+
+}  // namespace boost::redis::detail
+
+#endif  // BOOST_REDIS_READER_FSM_HPP

include/boost/redis/detail/receive_fsm.hpp

@@ -0,0 +1,58 @@
+//
+// Copyright (c) 2018-2026 Marcelo Zimbres Silva (mzimbres@gmail.com),
+// Ruben Perez Hidalgo (rubenperez038 at gmail dot com)
+//
+// Distributed under the Boost Software License, Version 1.0. (See accompanying
+// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+//
+
+#ifndef BOOST_REDIS_RECEIVE_FSM_HPP
+#define BOOST_REDIS_RECEIVE_FSM_HPP
+
+#include <boost/asio/cancellation_type.hpp>
+#include <boost/system/error_code.hpp>
+
+// Sans-io algorithm for async_receive2, as a finite state machine
+
+namespace boost::redis::detail {
+
+struct connection_state;
+
+struct receive_action {
+   enum class action_type
+   {
+      setup_cancellation,  // Set up the cancellation types supported by the composed operation
+      wait,                // Wait for a message to appear in the receive channel
+      drain_channel,       // Empty the receive channel
+      immediate,           // Call async_immediate
+      done,                // Complete
+   };
+
+   action_type type;
+   system::error_code ec;
+
+   receive_action(action_type type) noexcept
+   : type{type}
+   { }
+
+   receive_action(system::error_code ec) noexcept
+   : type{action_type::done}
+   , ec{ec}
+   { }
+};
+
+class receive_fsm {
+   int resume_point_{0};
+
+public:
+   receive_fsm() = default;
+
+   receive_action resume(
+      connection_state& st,
+      system::error_code ec,
+      asio::cancellation_type_t cancel_state);
+};
+
+}  // namespace boost::redis::detail
+
+#endif

include/boost/redis/detail/redis_stream.hpp

@@ -0,0 +1,251 @@
+/* Copyright (c) 2018-2025 Marcelo Zimbres Silva (mzimbres@gmail.com),
+ * Ruben Perez Hidalgo (rubenperez038 at gmail dot com)
+ *
+ * Distributed under the Boost Software License, Version 1.0. (See
+ * accompanying file LICENSE.txt)
+ */
+#ifndef BOOST_REDIS_REDIS_STREAM_HPP
+#define BOOST_REDIS_REDIS_STREAM_HPP
+
+#include <boost/redis/config.hpp>
+#include <boost/redis/detail/connect_fsm.hpp>
+#include <boost/redis/detail/connect_params.hpp>
+#include <boost/redis/error.hpp>
+#include <boost/redis/logger.hpp>
+
+#include <boost/asio/basic_waitable_timer.hpp>
+#include <boost/asio/cancel_after.hpp>
+#include <boost/asio/compose.hpp>
+#include <boost/asio/connect.hpp>
+#include <boost/asio/coroutine.hpp>
+#include <boost/asio/ip/basic_resolver.hpp>
+#include <boost/asio/ip/tcp.hpp>
+#include <boost/asio/local/stream_protocol.hpp>
+#include <boost/asio/ssl/context.hpp>
+#include <boost/asio/ssl/stream.hpp>
+#include <boost/asio/ssl/stream_base.hpp>
+#include <boost/asio/steady_timer.hpp>
+#include <boost/assert.hpp>
+#include <boost/system/error_code.hpp>
+
+#include <utility>
+
+namespace boost {
+namespace redis {
+namespace detail {
+
+template <class Executor>
+class redis_stream {
+   asio::ssl::context ssl_ctx_;
+   asio::ip::basic_resolver<asio::ip::tcp, Executor> resolv_;
+   asio::ssl::stream<asio::basic_stream_socket<asio::ip::tcp, Executor>> stream_;
+#ifdef BOOST_ASIO_HAS_LOCAL_SOCKETS
+   asio::basic_stream_socket<asio::local::stream_protocol, Executor> unix_socket_;
+#endif
+   typename asio::steady_timer::template rebind_executor<Executor>::other timer_;
+   redis_stream_state st_;
+
+   void reset_stream() { stream_ = {resolv_.get_executor(), ssl_ctx_}; }
+
+   struct connect_op {
+      redis_stream& obj_;
+      connect_fsm fsm_;
+      connect_params params_;
+
+      template <class Self>
+      void execute_action(Self& self, connect_action act)
+      {
+         // Prevent use-after-move errors
+         auto& obj = this->obj_;
+         auto params = this->params_;
+
+         switch (act.type) {
+            case connect_action_type::unix_socket_close:
+#ifdef BOOST_ASIO_HAS_LOCAL_SOCKETS
+            {
+               system::error_code ec;
+               obj.unix_socket_.close(ec);
+               (*this)(self, ec);  // This is a sync action
+            }
+#else
+               BOOST_ASSERT(false);
+#endif
+               return;
+            case connect_action_type::unix_socket_connect:
+#ifdef BOOST_ASIO_HAS_LOCAL_SOCKETS
+               obj.unix_socket_.async_connect(
+                  params.addr.unix_socket(),
+                  asio::cancel_after(obj.timer_, params.connect_timeout, std::move(self)));
+#else
+               BOOST_ASSERT(false);
+#endif
+               return;
+
+            case connect_action_type::tcp_resolve:
+               obj.resolv_.async_resolve(
+                  params.addr.tcp_address().host,
+                  params.addr.tcp_address().port,
+                  asio::cancel_after(obj.timer_, params.resolve_timeout, std::move(self)));
+               return;
+            case connect_action_type::ssl_stream_reset:
+               obj.reset_stream();
+               // this action does not require yielding. Execute the next action immediately
+               (*this)(self);
+               return;
+            case connect_action_type::ssl_handshake:
+               obj.stream_.async_handshake(
+                  asio::ssl::stream_base::client,
+                  asio::cancel_after(obj.timer_, params.ssl_handshake_timeout, std::move(self)));
+               return;
+            case connect_action_type::done:        self.complete(act.ec); break;
+            // Connect should use the specialized handler, where resolver results are available
+            case connect_action_type::tcp_connect:
+            default:                               BOOST_ASSERT(false);
+         }
+      }
+
+      // This overload will be used for connects
+      template <class Self>
+      void operator()(
+         Self& self,
+         system::error_code ec,
+         const asio::ip::tcp::endpoint& selected_endpoint)
+      {
+         auto act = fsm_.resume(
+            ec,
+            selected_endpoint,
+            obj_.st_,
+            self.get_cancellation_state().cancelled());
+         execute_action(self, act);
+      }
+
+      // This overload will be used for resolves
+      template <class Self>
+      void operator()(
+         Self& self,
+         system::error_code ec,
+         asio::ip::tcp::resolver::results_type endpoints)
+      {
+         auto act = fsm_.resume(ec, endpoints, obj_.st_, self.get_cancellation_state().cancelled());
+         if (act.type == connect_action_type::tcp_connect) {
+            auto& obj = this->obj_;  // prevent use-after-move errors
+            asio::async_connect(
+               obj.stream_.next_layer(),
+               std::move(endpoints),
+               asio::cancel_after(obj.timer_, params_.connect_timeout, std::move(self)));
+         } else {
+            execute_action(self, act);
+         }
+      }
+
+      template <class Self>
+      void operator()(Self& self, system::error_code ec = {})
+      {
+         auto act = fsm_.resume(ec, obj_.st_, self.get_cancellation_state().cancelled());
+         execute_action(self, act);
+      }
+   };
+
+public:
+   explicit redis_stream(Executor ex, asio::ssl::context&& ssl_ctx)
+   : ssl_ctx_{std::move(ssl_ctx)}
+   , resolv_{ex}
+   , stream_{ex, ssl_ctx_}
+#ifdef BOOST_ASIO_HAS_LOCAL_SOCKETS
+   , unix_socket_{ex}
+#endif
+   , timer_{std::move(ex)}
+   { }
+
+   // Executor. Required to satisfy the AsyncStream concept
+   using executor_type = Executor;
+   executor_type get_executor() noexcept { return resolv_.get_executor(); }
+
+   // Accessors
+   const auto& get_ssl_context() const noexcept { return ssl_ctx_; }
+   bool is_open() const
+   {
+#ifdef BOOST_ASIO_HAS_LOCAL_SOCKETS
+      if (st_.type == transport_type::unix_socket)
+         return unix_socket_.is_open();
+#endif
+      return stream_.next_layer().is_open();
+   }
+   auto& next_layer() { return stream_; }
+   const auto& next_layer() const { return stream_; }
+
+   // I/O
+   template <class CompletionToken>
+   auto async_connect(const connect_params& params, buffered_logger& l, CompletionToken&& token)
+   {
+      this->st_.type = params.addr.type();
+      return asio::async_compose<CompletionToken, void(system::error_code)>(
+         connect_op{*this, connect_fsm{l}, params},
+         token);
+   }
+
+   // These functions should only be used with callbacks (e.g. within async_compose function bodies)
+   template <class ConstBufferSequence, class CompletionToken>
+   void async_write_some(const ConstBufferSequence& buffers, CompletionToken&& token)
+   {
+      switch (st_.type) {
+         case transport_type::tcp:
+         {
+            stream_.next_layer().async_write_some(buffers, std::forward<CompletionToken>(token));
+            break;
+         }
+         case transport_type::tcp_tls:
+         {
+            stream_.async_write_some(buffers, std::forward<CompletionToken>(token));
+            break;
+         }
+#ifdef BOOST_ASIO_HAS_LOCAL_SOCKETS
+         case transport_type::unix_socket:
+         {
+            unix_socket_.async_write_some(buffers, std::forward<CompletionToken>(token));
+            break;
+         }
+#endif
+         default: BOOST_ASSERT(false);
+      }
+   }
+
+   template <class MutableBufferSequence, class CompletionToken>
+   void async_read_some(const MutableBufferSequence& buffers, CompletionToken&& token)
+   {
+      switch (st_.type) {
+         case transport_type::tcp:
+         {
+            return stream_.next_layer().async_read_some(
+               buffers,
+               std::forward<CompletionToken>(token));
+            break;
+         }
+         case transport_type::tcp_tls:
+         {
+            return stream_.async_read_some(buffers, std::forward<CompletionToken>(token));
+            break;
+         }
+#ifdef BOOST_ASIO_HAS_LOCAL_SOCKETS
+         case transport_type::unix_socket:
+         {
+            unix_socket_.async_read_some(buffers, std::forward<CompletionToken>(token));
+            break;
+         }
+#endif
+         default: BOOST_ASSERT(false);
+      }
+   }
+
+   // Cancels resolve operations. Resolve operations don't support per-operation
+   // cancellation, but resolvers have a cancel() function. Resolve operations are
+   // in general blocking and run in a separate thread. cancel() has effect only
+   // if the operation hasn't started yet. Still, trying is better than nothing
+   void cancel_resolve() { resolv_.cancel(); }
+};
+
+}  // namespace detail
+}  // namespace redis
+}  // namespace boost
+
+#endif

include/boost/redis/detail/resolver.hpp

@@ -1,137 +0,0 @@
-/* Copyright (c) 2018-2023 Marcelo Zimbres Silva (mzimbres@gmail.com)
- *
- * Distributed under the Boost Software License, Version 1.0. (See
- * accompanying file LICENSE.txt)
- */
-
-#ifndef BOOST_REDIS_RESOLVER_HPP
-#define BOOST_REDIS_RESOLVER_HPP
-
-#include <boost/redis/config.hpp>
-#include <boost/redis/detail/helper.hpp>
-#include <boost/redis/error.hpp>
-#include <boost/asio/compose.hpp>
-#include <boost/asio/coroutine.hpp>
-#include <boost/asio/experimental/parallel_group.hpp>
-#include <boost/asio/ip/tcp.hpp>
-#include <boost/asio/steady_timer.hpp>
-#include <string>
-#include <chrono>
-
-namespace boost::redis::detail
-{
-
-template <class Resolver>
-struct resolve_op {
-   Resolver* resv_ = nullptr;
-   asio::coroutine coro{};
-
-   template <class Self>
-   void operator()( Self& self
-                  , std::array<std::size_t, 2> order = {}
-                  , system::error_code ec1 = {}
-                  , asio::ip::tcp::resolver::results_type res = {}
-                  , system::error_code ec2 = {})
-   {
-      BOOST_ASIO_CORO_REENTER (coro)
-      {
-         resv_->timer_.expires_after(resv_->timeout_);
-
-         BOOST_ASIO_CORO_YIELD
-         asio::experimental::make_parallel_group(
-            [this](auto token)
-            {
-               return resv_->resv_.async_resolve(resv_->addr_.host, resv_->addr_.port, token);
-            },
-            [this](auto token) { return resv_->timer_.async_wait(token);}
-         ).async_wait(
-            asio::experimental::wait_for_one(),
-            std::move(self));
-
-         if (is_cancelled(self)) {
-            self.complete(asio::error::operation_aborted);
-            return;
-         }
-
-         switch (order[0]) {
-            case 0: {
-               // Resolver completed first.
-               resv_->results_ = res;
-               self.complete(ec1);
-            } break;
-
-            case 1: {
-               if (ec2) {
-                  // Timer completed first with error, perhaps a
-                  // cancellation going on.
-                  self.complete(ec2);
-               } else {
-                  // Timer completed first without an error, this is a
-                  // resolve timeout.
-                  self.complete(error::resolve_timeout);
-               }
-            } break;
-
-            default: BOOST_ASSERT(false);
-         }
-      }
-   }
-};
-
-template <class Executor>
-class resolver {
-public:
-   using timer_type =
-      asio::basic_waitable_timer<
-         std::chrono::steady_clock,
-         asio::wait_traits<std::chrono::steady_clock>,
-         Executor>;
-
-   resolver(Executor ex) : resv_{ex} , timer_{ex} {}
-
-   template <class CompletionToken>
-   auto async_resolve(CompletionToken&& token)
-   {
-      return asio::async_compose
-         < CompletionToken
-         , void(system::error_code)
-         >(resolve_op<resolver>{this}, token, resv_);
-   }
-
-   std::size_t cancel(operation op)
-   {
-      switch (op) {
-         case operation::resolve:
-         case operation::all:
-            resv_.cancel();
-            timer_.cancel();
-            break;
-         default: /* ignore */;
-      }
-
-      return 0;
-   }
-
-   auto const& results() const noexcept
-      { return results_;}
-
-   void set_config(config const& cfg)
-   {
-      addr_ = cfg.addr;
-      timeout_ = cfg.resolve_timeout;
-   }
-
-private:
-   using resolver_type = asio::ip::basic_resolver<asio::ip::tcp, Executor>;
-   template <class> friend struct resolve_op;
-
-   resolver_type resv_;
-   timer_type timer_;
-   address addr_;
-   std::chrono::steady_clock::duration timeout_;
-   asio::ip::tcp::resolver::results_type results_;
-};
-
-} // boost::redis::detail
-
-#endif // BOOST_REDIS_RESOLVER_HPP

include/boost/redis/detail/resp3_type_to_error.hpp

@@ -0,0 +1,29 @@
+/* Copyright (c) 2018-2024 Marcelo Zimbres Silva (mzimbres@gmail.com)
+ *
+ * Distributed under the Boost Software License, Version 1.0. (See
+ * accompanying file LICENSE.txt)
+ */
+
+#ifndef BOOST_RESP3_TYPE_TO_ERROR_HPP
+#define BOOST_RESP3_TYPE_TO_ERROR_HPP
+
+#include <boost/redis/error.hpp>
+#include <boost/redis/resp3/type.hpp>
+
+#include <boost/assert.hpp>
+
+namespace boost::redis::detail {
+
+inline error resp3_type_to_error(resp3::type t)
+{
+   switch (t) {
+      case resp3::type::simple_error: return error::resp3_simple_error;
+      case resp3::type::blob_error:   return error::resp3_blob_error;
+      case resp3::type::null:         return error::resp3_null;
+      default:                        BOOST_ASSERT_MSG(false, "Unexpected data type."); return error::resp3_simple_error;
+   }
+}
+
+}  // namespace boost::redis::detail
+
+#endif  // BOOST_REDIS_ADAPTER_RESULT_HPP

include/boost/redis/detail/run_fsm.hpp

@@ -0,0 +1,67 @@
+//
+// Copyright (c) 2025 Marcelo Zimbres Silva (mzimbres@gmail.com),
+// Ruben Perez Hidalgo (rubenperez038 at gmail dot com)
+//
+// Distributed under the Boost Software License, Version 1.0. (See accompanying
+// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+//
+
+#ifndef BOOST_REDIS_RUN_FSM_HPP
+#define BOOST_REDIS_RUN_FSM_HPP
+
+#include <boost/redis/detail/connect_params.hpp>
+
+#include <boost/asio/cancellation_type.hpp>
+#include <boost/system/error_code.hpp>
+
+// Sans-io algorithm for async_run, as a finite state machine
+
+namespace boost::redis::detail {
+
+// Forward decls
+struct connection_state;
+
+// What should we do next?
+enum class run_action_type
+{
+   done,                   // Call the final handler
+   immediate,              // Call asio::async_immediate
+   connect,                // Transport connection establishment
+   sentinel_resolve,       // Contact Sentinels to resolve the master's address
+   parallel_group,         // Run the reader, writer and friends
+   cancel_receive,         // Cancel the receiver channel
+   wait_for_reconnection,  // Sleep for the reconnection period
+};
+
+struct run_action {
+   run_action_type type;
+   system::error_code ec;
+
+   run_action(run_action_type type) noexcept
+   : type{type}
+   { }
+
+   run_action(system::error_code ec) noexcept
+   : type{run_action_type::done}
+   , ec{ec}
+   { }
+};
+
+class run_fsm {
+   int resume_point_{0};
+   system::error_code stored_ec_;
+
+public:
+   run_fsm() = default;
+
+   run_action resume(
+      connection_state& st,
+      system::error_code ec,
+      asio::cancellation_type_t cancel_state);
+};
+
+connect_params make_run_connect_params(const connection_state& st);
+
+}  // namespace boost::redis::detail
+
+#endif  // BOOST_REDIS_CONNECTOR_HPP

include/boost/redis/detail/runner.hpp

@@ -1,276 +0,0 @@
-/* Copyright (c) 2018-2023 Marcelo Zimbres Silva (mzimbres@gmail.com)
- *
- * Distributed under the Boost Software License, Version 1.0. (See
- * accompanying file LICENSE.txt)
- */
-
-#ifndef BOOST_REDIS_RUNNER_HPP
-#define BOOST_REDIS_RUNNER_HPP
-
-#include <boost/redis/detail/health_checker.hpp>
-#include <boost/redis/config.hpp>
-#include <boost/redis/response.hpp>
-#include <boost/redis/detail/helper.hpp>
-#include <boost/redis/error.hpp>
-#include <boost/redis/logger.hpp>
-#include <boost/redis/operation.hpp>
-#include <boost/redis/detail/connector.hpp>
-#include <boost/redis/detail/resolver.hpp>
-#include <boost/redis/detail/handshaker.hpp>
-#include <boost/asio/compose.hpp>
-#include <boost/asio/connect.hpp>
-#include <boost/asio/coroutine.hpp>
-#include <boost/asio/experimental/parallel_group.hpp>
-#include <boost/asio/ip/tcp.hpp>
-#include <boost/asio/steady_timer.hpp>
-#include <string>
-#include <memory>
-#include <chrono>
-
-namespace boost::redis::detail
-{
-
-template <class Runner, class Connection, class Logger>
-struct hello_op {
-   Runner* runner_ = nullptr;
-   Connection* conn_ = nullptr;
-   Logger logger_;
-   asio::coroutine coro_{};
-
-   template <class Self>
-   void operator()(Self& self, system::error_code ec = {}, std::size_t = 0)
-   {
-      BOOST_ASIO_CORO_REENTER (coro_)
-      {
-         runner_->hello_req_.clear();
-         if (runner_->hello_resp_.has_value())
-            runner_->hello_resp_.value().clear();
-         runner_->add_hello();
-
-         BOOST_ASIO_CORO_YIELD
-         conn_->async_exec(runner_->hello_req_, runner_->hello_resp_, std::move(self));
-         logger_.on_hello(ec, runner_->hello_resp_);
-
-         if (ec || runner_->has_error_in_response() || is_cancelled(self)) {
-            logger_.trace("hello-op: error/canceled. Exiting ...");
-            conn_->cancel(operation::run);
-            self.complete(!!ec ? ec : asio::error::operation_aborted);
-            return;
-         }
-
-         self.complete({});
-      }
-   }
-};
-
-template <class Runner, class Connection, class Logger>
-class runner_op {
-private:
-   Runner* runner_ = nullptr;
-   Connection* conn_ = nullptr;
-   Logger logger_;
-   asio::coroutine coro_{};
-
-public:
-   runner_op(Runner* runner, Connection* conn, Logger l)
-   : runner_{runner}
-   , conn_{conn}
-   , logger_{l}
-   {}
-
-   template <class Self>
-   void operator()( Self& self
-                  , std::array<std::size_t, 3> order = {}
-                  , system::error_code ec0 = {}
-                  , system::error_code ec1 = {}
-                  , system::error_code ec2 = {}
-                  , std::size_t = 0)
-   {
-      BOOST_ASIO_CORO_REENTER (coro_)
-      {
-         BOOST_ASIO_CORO_YIELD
-         asio::experimental::make_parallel_group(
-            [this](auto token) { return runner_->async_run_all(*conn_, logger_, token); },
-            [this](auto token) { return runner_->health_checker_.async_check_health(*conn_, logger_, token); },
-            [this](auto token) { return runner_->async_hello(*conn_, logger_, token); }
-         ).async_wait(
-            asio::experimental::wait_for_all(),
-            std::move(self));
-
-         logger_.on_runner(ec0, ec1, ec2);
-
-         if (is_cancelled(self)) {
-            self.complete(asio::error::operation_aborted);
-            return;
-         }
-
-         if (ec0 == error::connect_timeout || ec0 == error::resolve_timeout) {
-            self.complete(ec0);
-            return;
-         }
-
-         if (order[0] == 2 && !!ec2) {
-            self.complete(ec2);
-            return;
-         }
-
-         if (order[0] == 1 && ec1 == error::pong_timeout) {
-            self.complete(ec1);
-            return;
-         }
-
-         self.complete(ec0);
-      }
-   }
-};
-
-template <class Runner, class Connection, class Logger>
-struct run_all_op {
-   Runner* runner_ = nullptr;
-   Connection* conn_ = nullptr;
-   Logger logger_;
-   asio::coroutine coro_{};
-
-   template <class Self>
-   void operator()(Self& self, system::error_code ec = {}, std::size_t = 0)
-   {
-      BOOST_ASIO_CORO_REENTER (coro_)
-      {
-         BOOST_ASIO_CORO_YIELD
-         runner_->resv_.async_resolve(std::move(self));
-         logger_.on_resolve(ec, runner_->resv_.results());
-         BOOST_REDIS_CHECK_OP0(conn_->cancel(operation::run);)
-
-         BOOST_ASIO_CORO_YIELD
-         runner_->ctor_.async_connect(conn_->next_layer().next_layer(), runner_->resv_.results(), std::move(self));
-         logger_.on_connect(ec, runner_->ctor_.endpoint());
-         BOOST_REDIS_CHECK_OP0(conn_->cancel(operation::run);)
-
-         if (conn_->use_ssl()) {
-            BOOST_ASIO_CORO_YIELD
-            runner_->hsher_.async_handshake(conn_->next_layer(), std::move(self));
-            logger_.on_ssl_handshake(ec);
-            BOOST_REDIS_CHECK_OP0(conn_->cancel(operation::run);)
-         }
-
-         BOOST_ASIO_CORO_YIELD
-         conn_->async_run_lean(runner_->cfg_, logger_, std::move(self));
-         BOOST_REDIS_CHECK_OP0(;)
-         self.complete(ec);
-      }
-   }
-};
-
-template <class Executor>
-class runner {
-public:
-   runner(Executor ex, config cfg)
-   : resv_{ex}
-   , ctor_{ex}
-   , hsher_{ex}
-   , health_checker_{ex}
-   , cfg_{cfg}
-   { }
-
-   std::size_t cancel(operation op)
-   {
-      resv_.cancel(op);
-      ctor_.cancel(op);
-      hsher_.cancel(op);
-      health_checker_.cancel(op);
-      return 0U;
-   }
-
-   void set_config(config const& cfg)
-   {
-      cfg_ = cfg;
-      resv_.set_config(cfg);
-      ctor_.set_config(cfg);
-      hsher_.set_config(cfg);
-      health_checker_.set_config(cfg);
-   }
-
-   template <class Connection, class Logger, class CompletionToken>
-   auto async_run(Connection& conn, Logger l, CompletionToken token)
-   {
-      return asio::async_compose
-         < CompletionToken
-         , void(system::error_code)
-         >(runner_op<runner, Connection, Logger>{this, &conn, l}, token, conn);
-   }
-
-   config const& get_config() const noexcept {return cfg_;}
-
-private:
-   using resolver_type = resolver<Executor>;
-   using connector_type = connector<Executor>;
-   using handshaker_type = detail::handshaker<Executor>;
-   using health_checker_type = health_checker<Executor>;
-   using timer_type = typename connector_type::timer_type;
-
-   template <class, class, class> friend struct run_all_op;
-   template <class, class, class> friend class runner_op;
-   template <class, class, class> friend struct hello_op;
-
-   template <class Connection, class Logger, class CompletionToken>
-   auto async_run_all(Connection& conn, Logger l, CompletionToken token)
-   {
-      return asio::async_compose
-         < CompletionToken
-         , void(system::error_code)
-         >(run_all_op<runner, Connection, Logger>{this, &conn, l}, token, conn);
-   }
-
-   template <class Connection, class Logger, class CompletionToken>
-   auto async_hello(Connection& conn, Logger l, CompletionToken token)
-   {
-      return asio::async_compose
-         < CompletionToken
-         , void(system::error_code)
-         >(hello_op<runner, Connection, Logger>{this, &conn, l}, token, conn);
-   }
-
-   void add_hello()
-   {
-      if (!cfg_.username.empty() && !cfg_.password.empty() && !cfg_.clientname.empty())
-         hello_req_.push("HELLO", "3", "AUTH", cfg_.username, cfg_.password, "SETNAME", cfg_.clientname);
-      else if (cfg_.username.empty() && cfg_.password.empty() && cfg_.clientname.empty())
-         hello_req_.push("HELLO", "3");
-      else if (cfg_.clientname.empty())
-         hello_req_.push("HELLO", "3", "AUTH", cfg_.username, cfg_.password);
-      else
-         hello_req_.push("HELLO", "3", "SETNAME", cfg_.clientname);
-
-      if (cfg_.database_index && cfg_.database_index.value() != 0)
-         hello_req_.push("SELECT", cfg_.database_index.value());
-   }
-
-   bool has_error_in_response() const noexcept
-   {
-      if (!hello_resp_.has_value())
-         return true;
-
-      auto f = [](auto const& e)
-      {
-         switch (e.data_type) {
-            case resp3::type::simple_error:
-            case resp3::type::blob_error: return true;
-            default: return false;
-         }
-      };
-
-      return std::any_of(std::cbegin(hello_resp_.value()), std::cend(hello_resp_.value()), f);
-   }
-
-   resolver_type resv_;
-   connector_type ctor_;
-   handshaker_type hsher_;
-   health_checker_type health_checker_;
-   request hello_req_;
-   generic_response hello_resp_;
-   config cfg_;
-};
-
-} // boost::redis::detail
-
-#endif // BOOST_REDIS_RUNNER_HPP

include/boost/redis/detail/sentinel_resolve_fsm.hpp

@@ -0,0 +1,93 @@
+//
+// Copyright (c) 2025 Marcelo Zimbres Silva (mzimbres@gmail.com),
+// Ruben Perez Hidalgo (rubenperez038 at gmail dot com)
+//
+// Distributed under the Boost Software License, Version 1.0. (See accompanying
+// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+//
+
+#ifndef BOOST_REDIS_SENTINEL_RESOLVE_FSM_HPP
+#define BOOST_REDIS_SENTINEL_RESOLVE_FSM_HPP
+
+#include <boost/redis/adapter/any_adapter.hpp>
+#include <boost/redis/config.hpp>
+#include <boost/redis/detail/connect_params.hpp>
+
+#include <boost/asio/cancellation_type.hpp>
+#include <boost/assert.hpp>
+#include <boost/system/error_code.hpp>
+
+// Sans-io algorithm for async_sentinel_resolve, as a finite state machine
+
+namespace boost::redis::detail {
+
+// Forward decls
+struct connection_state;
+
+class sentinel_action {
+public:
+   enum class type
+   {
+      done,     // Call the final handler
+      connect,  // Transport connection establishment
+      request,  // Send the Sentinel request
+   };
+
+   sentinel_action(system::error_code ec) noexcept
+   : type_(type::done)
+   , ec_(ec)
+   { }
+
+   sentinel_action(const address& addr) noexcept
+   : type_(type::connect)
+   , connect_(&addr)
+   { }
+
+   static sentinel_action request() { return {type::request}; }
+
+   type get_type() const { return type_; }
+
+   [[nodiscard]]
+   system::error_code error() const
+   {
+      BOOST_ASSERT(type_ == type::done);
+      return ec_;
+   }
+
+   const address& connect_addr() const
+   {
+      BOOST_ASSERT(type_ == type::connect);
+      return *connect_;
+   }
+
+private:
+   type type_;
+   union {
+      system::error_code ec_;
+      const address* connect_;
+   };
+
+   sentinel_action(type type) noexcept
+   : type_(type)
+   { }
+};
+
+class sentinel_resolve_fsm {
+   int resume_point_{0};
+   std::size_t idx_{0u};
+
+public:
+   sentinel_resolve_fsm() = default;
+
+   sentinel_action resume(
+      connection_state& st,
+      system::error_code ec,
+      asio::cancellation_type_t cancel_state);
+};
+
+connect_params make_sentinel_connect_params(const config& cfg, const address& sentinel_addr);
+any_adapter make_sentinel_adapter(connection_state& st);
+
+}  // namespace boost::redis::detail
+
+#endif  // BOOST_REDIS_CONNECTOR_HPP

include/boost/redis/detail/subscription_tracker.hpp

@@ -0,0 +1,35 @@
+//
+// Copyright (c) 2025 Marcelo Zimbres Silva (mzimbres@gmail.com),
+// Ruben Perez Hidalgo (rubenperez038 at gmail dot com)
+//
+// Distributed under the Boost Software License, Version 1.0. (See accompanying
+// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+//
+
+#ifndef BOOST_REDIS_SUBSCRIPTION_TRACKER_HPP
+#define BOOST_REDIS_SUBSCRIPTION_TRACKER_HPP
+
+#include <set>
+#include <string>
+
+namespace boost::redis {
+
+class request;
+
+namespace detail {
+
+class subscription_tracker {
+   std::set<std::string> channels_;
+   std::set<std::string> pchannels_;
+
+public:
+   subscription_tracker() = default;
+   void clear();
+   void commit_changes(const request& req);
+   void compose_subscribe_request(request& to) const;
+};
+
+}  // namespace detail
+}  // namespace boost::redis
+
+#endif

include/boost/redis/detail/write.hpp

@@ -1,4 +1,4 @@
-/* Copyright (c) 2018-2023 Marcelo Zimbres Silva (mzimbres@gmail.com)
+/* Copyright (c) 2018-2024 Marcelo Zimbres Silva (mzimbres@gmail.com)
  *
  * Distributed under the Boost Software License, Version 1.0. (See
  * accompanying file LICENSE.txt)
@@ -7,40 +7,39 @@
 #ifndef BOOST_REDIS_WRITE_HPP
 #define BOOST_REDIS_WRITE_HPP
 
-#include <boost/asio/write.hpp>
 #include <boost/redis/request.hpp>
 
+#include <boost/asio/write.hpp>
+
 namespace boost::redis::detail {
 
-/** \brief Writes a request synchronously.
- *  \ingroup low-level-api
+/** @brief Writes a request synchronously.
  *
- *  \param stream Stream to write the request to.
- *  \param req Request to write.
+ *  @param stream Stream to write the request to.
+ *  @param req Request to write.
  */
-template<class SyncWriteStream>
+template <class SyncWriteStream>
 auto write(SyncWriteStream& stream, request const& req)
 {
    return asio::write(stream, asio::buffer(req.payload()));
 }
 
-template<class SyncWriteStream>
+template <class SyncWriteStream>
 auto write(SyncWriteStream& stream, request const& req, system::error_code& ec)
 {
    return asio::write(stream, asio::buffer(req.payload()), ec);
 }
 
-/** \brief Writes a request asynchronously.
- *  \ingroup low-level-api
+/** @brief Writes a request asynchronously.
  *
- *  \param stream Stream to write the request to.
- *  \param req Request to write.
- *  \param token Asio completion token.
+ *  @param stream Stream to write the request to.
+ *  @param req Request to write.
+ *  @param token Asio completion token.
  */
-template<
+template <
    class AsyncWriteStream,
-   class CompletionToken = asio::default_completion_token_t<typename AsyncWriteStream::executor_type>
-   >
+   class CompletionToken =
+      asio::default_completion_token_t<typename AsyncWriteStream::executor_type> >
 auto async_write(
    AsyncWriteStream& stream,
    request const& req,
@@ -50,6 +49,6 @@ auto async_write(
    return asio::async_write(stream, asio::buffer(req.payload()), token);
 }
 
-} // boost::redis::detail
+}  // namespace boost::redis::detail
 
-#endif // BOOST_REDIS_WRITE_HPP
+#endif  // BOOST_REDIS_WRITE_HPP

include/boost/redis/detail/writer_fsm.hpp

@@ -0,0 +1,92 @@
+//
+// Copyright (c) 2025 Marcelo Zimbres Silva (mzimbres@gmail.com),
+// Ruben Perez Hidalgo (rubenperez038 at gmail dot com)
+//
+// Distributed under the Boost Software License, Version 1.0. (See accompanying
+// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+//
+
+#ifndef BOOST_REDIS_WRITER_FSM_HPP
+#define BOOST_REDIS_WRITER_FSM_HPP
+
+#include <boost/asio/cancellation_type.hpp>
+#include <boost/assert.hpp>
+#include <boost/system/error_code.hpp>
+
+#include <chrono>
+#include <cstddef>
+
+// Sans-io algorithm for the writer task, as a finite state machine
+
+namespace boost::redis::detail {
+
+// Forward decls
+struct connection_state;
+
+// What should we do next?
+enum class writer_action_type
+{
+   done,        // Call the final handler
+   write_some,  // Issue a write on the stream
+   wait,        // Wait until there is data to be written
+};
+
+class writer_action {
+   writer_action_type type_;
+   union {
+      system::error_code ec_;
+      std::chrono::steady_clock::duration timeout_;
+   };
+
+   writer_action(writer_action_type type, std::chrono::steady_clock::duration t) noexcept
+   : type_{type}
+   , timeout_{t}
+   { }
+
+public:
+   writer_action_type type() const { return type_; }
+
+   writer_action(system::error_code ec) noexcept
+   : type_{writer_action_type::done}
+   , ec_{ec}
+   { }
+
+   static writer_action write_some(std::chrono::steady_clock::duration timeout)
+   {
+      return {writer_action_type::write_some, timeout};
+   }
+
+   static writer_action wait(std::chrono::steady_clock::duration timeout)
+   {
+      return {writer_action_type::wait, timeout};
+   }
+
+   system::error_code error() const
+   {
+      BOOST_ASSERT(type_ == writer_action_type::done);
+      return ec_;
+   }
+
+   std::chrono::steady_clock::duration timeout() const
+   {
+      BOOST_ASSERT(type_ == writer_action_type::write_some || type_ == writer_action_type::wait);
+      return timeout_;
+   }
+};
+
+class writer_fsm {
+   int resume_point_{0};
+
+public:
+   writer_fsm() = default;
+
+   writer_action resume(
+      connection_state& st,
+      system::error_code ec,
+      std::size_t bytes_written,
+      asio::cancellation_type_t cancel_state);
+};
+
+}  // namespace boost::redis::detail
+
+#endif  // BOOST_REDIS_CONNECTOR_HPP

include/boost/redis/error.hpp

@@ -1,4 +1,4 @@
-/* Copyright (c) 2018-2023 Marcelo Zimbres Silva (mzimbres@gmail.com)
+/* Copyright (c) 2018-2024 Marcelo Zimbres Silva (mzimbres@gmail.com)
  *
  * Distributed under the Boost Software License, Version 1.0. (See
  * accompanying file LICENSE.txt)
@@ -11,9 +11,7 @@
 
 namespace boost::redis {
 
-/** \brief Generic errors.
- *  \ingroup high-level-api
- */
+/// Generic errors.
 enum class error
 {
    /// Invalid RESP3 type.
@@ -70,33 +68,70 @@ enum class error
    /// Connect timeout
    connect_timeout,
 
-   /// Connect timeout
+   /// The server didn't answer the health checks on time and didn't send any data during the health check period.
    pong_timeout,
 
    /// SSL handshake timeout
    ssl_handshake_timeout,
 
-   /// Can't receive push synchronously without blocking
+   /// (Deprecated) Can't receive push synchronously without blocking
    sync_receive_push_failed,
 
    /// Incompatible node depth.
    incompatible_node_depth,
+
+   /// The setup request sent during connection establishment failed (the name is historical).
+   resp3_hello,
+
+   /// The configuration specified a UNIX socket address, but UNIX sockets are not supported by the system.
+   unix_sockets_unsupported,
+
+   /// The configuration specified UNIX sockets with SSL, which is not supported.
+   unix_sockets_ssl_unsupported,
+
+   /// Reading data from the socket would exceed the maximum size allowed of the read buffer.
+   exceeds_maximum_read_buffer_size,
+
+   /// Timeout while writing data to the server.
+   write_timeout,
+
+   /// The configuration specified UNIX sockets with Sentinel, which is not supported.
+   sentinel_unix_sockets_unsupported,
+
+   /// No Sentinel could be used to obtain the address of the Redis server.
+   /// Sentinels might be unreachable, have authentication misconfigured or may not know about
+   /// the configured master. Turn logging on for details.
+   sentinel_resolve_failed,
+
+   /// The contacted server is not a master as expected.
+   /// This is likely a transient failure caused by a Sentinel failover in progress.
+   role_check_failed,
+
+   /// Expects a RESP3 string, but got a different data type.
+   expects_resp3_string,
+
+   /// Expects a RESP3 array, but got a different data type.
+   expects_resp3_array,
+
+   /// A @ref basic_connection::async_receive2 operation is already running.
+   /// Only one of such operations might be running at any point in time.
+   already_running,
 };
 
-/** \internal
- *  \brief Creates a error_code object from an error.
- *  \param e Error code.
- *  \ingroup any
+/**
+ * @brief Creates a error_code object from an error.
+ *
+ * @param e Error code.
  */
 auto make_error_code(error e) -> system::error_code;
 
-} // boost::redis
+}  // namespace boost::redis
 
 namespace std {
 
-template<>
-struct is_error_code_enum<::boost::redis::error> : std::true_type {};
+template <>
+struct is_error_code_enum<::boost::redis::error> : std::true_type { };
 
-} // std
+}  // namespace std
 
-#endif // BOOST_REDIS_ERROR_HPP
+#endif  // BOOST_REDIS_ERROR_HPP

include/boost/redis/ignore.hpp

@@ -1,5 +1,5 @@
 
-/* Copyright (c) 2018-2023 Marcelo Zimbres Silva (mzimbres@gmail.com)
+/* Copyright (c) 2018-2024 Marcelo Zimbres Silva (mzimbres@gmail.com)
  *
  * Distributed under the Boost Software License, Version 1.0. (See
  * accompanying file LICENSE.txt)
@@ -13,30 +13,27 @@
 #include <tuple>
 #include <type_traits>
 
-namespace boost::redis
-{
+namespace boost::redis {
 
 /** @brief Type used to ignore responses.
- *  @ingroup high-level-api
  *
- *  For example
+ *  For example:
  *
  *  @code
  *  response<ignore_t, std::string, ignore_t> resp;
  *  @endcode
  *
- *  will ignore the first and third responses. RESP3 errors won't be
+ *  This will ignore the first and third responses. RESP3 errors won't be
  *  ignore but will cause `async_exec` to complete with an error.
  */
 using ignore_t = std::decay_t<decltype(std::ignore)>;
 
 /** @brief Global ignore object.
- *  @ingroup high-level-api
  *
- *  Can be used to ignore responses to a request
+ *  Can be used to ignore responses to a request. For example:
  *
  *  @code
- *  conn->async_exec(req, ignore, ...);
+ *  co_await conn.async_exec(req, ignore);
  *  @endcode
  *
  *  RESP3 errors won't be ignore but will cause `async_exec` to
@@ -44,6 +41,6 @@ using ignore_t = std::decay_t<decltype(std::ignore)>;
  */
 extern ignore_t ignore;
 
-} // boost::redis
+}  // namespace boost::redis
 
-#endif // BOOST_REDIS_IGNORE_HPP
+#endif  // BOOST_REDIS_IGNORE_HPP

include/boost/redis/impl/connect_fsm.ipp

@@ -0,0 +1,218 @@
+//
+// Copyright (c) 2025 Marcelo Zimbres Silva (mzimbres@gmail.com),
+// Ruben Perez Hidalgo (rubenperez038 at gmail dot com)
+//
+// Distributed under the Boost Software License, Version 1.0. (See accompanying
+// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+//
+
+#include <boost/redis/config.hpp>
+#include <boost/redis/detail/connect_fsm.hpp>
+#include <boost/redis/detail/coroutine.hpp>
+#include <boost/redis/error.hpp>
+#include <boost/redis/impl/log_utils.hpp>
+
+#include <boost/asio/cancellation_type.hpp>
+#include <boost/asio/error.hpp>
+#include <boost/asio/ip/tcp.hpp>
+#include <boost/assert.hpp>
+
+#include <string>
+
+namespace boost::redis::detail {
+
+// Logging
+inline void format_tcp_endpoint(const asio::ip::tcp::endpoint& ep, std::string& to)
+{
+   // This formatting is inspired by Asio's endpoint operator<<
+   const auto& addr = ep.address();
+   if (addr.is_v6())
+      to += '[';
+   to += addr.to_string();
+   if (addr.is_v6())
+      to += ']';
+   to += ':';
+   to += std::to_string(ep.port());
+}
+
+template <>
+struct log_traits<asio::ip::tcp::endpoint> {
+   static inline void log(std::string& to, const asio::ip::tcp::endpoint& value)
+   {
+      format_tcp_endpoint(value, to);
+   }
+};
+
+template <>
+struct log_traits<asio::ip::tcp::resolver::results_type> {
+   static inline void log(std::string& to, const asio::ip::tcp::resolver::results_type& value)
+   {
+      auto iter = value.cbegin();
+      auto end = value.cend();
+
+      if (iter != end) {
+         format_tcp_endpoint(iter->endpoint(), to);
+         ++iter;
+         for (; iter != end; ++iter) {
+            to += ", ";
+            format_tcp_endpoint(iter->endpoint(), to);
+         }
+      }
+   }
+};
+
+inline system::error_code translate_timeout_error(
+   system::error_code io_ec,
+   asio::cancellation_type_t cancel_state,
+   error code_if_cancelled)
+{
+   // Translates cancellations and timeout errors into a single error_code.
+   //   - Cancellation state set, and an I/O error: the entire operation was cancelled.
+   //     The I/O code (probably operation_aborted) is appropriate.
+   //   - Cancellation state set, and no I/O error: same as above, but the cancellation
+   //     arrived after the operation completed and before the handler was called. Set the code here.
+   //   - No cancellation state set, I/O error set to operation_aborted: since we use cancel_after,
+   //     this means a timeout.
+   //   - Otherwise, respect the I/O error.
+   if ((cancel_state & asio::cancellation_type_t::terminal) != asio::cancellation_type_t::none) {
+      return io_ec ? io_ec : asio::error::operation_aborted;
+   }
+   return io_ec == asio::error::operation_aborted ? code_if_cancelled : io_ec;
+}
+
+connect_action connect_fsm::resume(
+   system::error_code ec,
+   const asio::ip::tcp::resolver::results_type& resolver_results,
+   redis_stream_state& st,
+   asio::cancellation_type_t cancel_state)
+{
+   // Translate error codes
+   ec = translate_timeout_error(ec, cancel_state, error::resolve_timeout);
+
+   // Log it
+   if (ec) {
+      log_info(*lgr_, "Connect: hostname resolution failed: ", ec);
+   } else {
+      log_debug(*lgr_, "Connect: hostname resolution results: ", resolver_results);
+   }
+
+   // Delegate to the regular resume function
+   return resume(ec, st, cancel_state);
+}
+
+connect_action connect_fsm::resume(
+   system::error_code ec,
+   const asio::ip::tcp::endpoint& selected_endpoint,
+   redis_stream_state& st,
+   asio::cancellation_type_t cancel_state)
+{
+   // Translate error codes
+   ec = translate_timeout_error(ec, cancel_state, error::connect_timeout);
+
+   // Log it
+   if (ec) {
+      log_info(*lgr_, "Connect: TCP connect failed: ", ec);
+   } else {
+      log_debug(*lgr_, "Connect: TCP connect succeeded. Selected endpoint: ", selected_endpoint);
+   }
+
+   // Delegate to the regular resume function
+   return resume(ec, st, cancel_state);
+}
+
+connect_action connect_fsm::resume(
+   system::error_code ec,
+   redis_stream_state& st,
+   asio::cancellation_type_t cancel_state)
+{
+   switch (resume_point_) {
+      BOOST_REDIS_CORO_INITIAL
+
+      if (st.type == transport_type::unix_socket) {
+         // Reset the socket, to discard any previous state. Ignore any errors
+         BOOST_REDIS_YIELD(resume_point_, 1, connect_action_type::unix_socket_close)
+
+         // Connect to the socket
+         BOOST_REDIS_YIELD(resume_point_, 2, connect_action_type::unix_socket_connect)
+
+         // Fix error codes. If we were cancelled and the code is operation_aborted,
+         // it is because per-operation cancellation was activated. If we were not cancelled
+         // but the operation failed with operation_aborted, it's a timeout.
+         // Also check for cancellations that didn't cause a failure
+         ec = translate_timeout_error(ec, cancel_state, error::connect_timeout);
+
+         // Log it
+         if (ec) {
+            log_info(*lgr_, "Connect: UNIX socket connect failed: ", ec);
+         } else {
+            log_debug(*lgr_, "Connect: UNIX socket connect succeeded");
+         }
+
+         // If this failed, we can't continue
+         if (ec) {
+            return ec;
+         }
+
+         // Done
+         return system::error_code();
+      } else {
+         // ssl::stream doesn't support being re-used. If we're to use
+         // TLS and the stream has been used, re-create it.
+         // Must be done before anything else is done on the stream.
+         // We don't need to close the TCP socket if using plaintext TCP
+         // because range-connect closes open sockets, while individual connect doesn't
+         if (st.type == transport_type::tcp_tls && st.ssl_stream_used) {
+            BOOST_REDIS_YIELD(resume_point_, 3, connect_action_type::ssl_stream_reset)
+         }
+
+         // Resolve names. The continuation needs access to the returned
+         // endpoints, and is a specialized resume() that will call this function
+         BOOST_REDIS_YIELD(resume_point_, 4, connect_action_type::tcp_resolve)
+
+         // If this failed, we can't continue (error code translation already performed here)
+         if (ec) {
+            return ec;
+         }
+
+         // Now connect to the endpoints returned by the resolver.
+         // This has a specialized resume(), too
+         BOOST_REDIS_YIELD(resume_point_, 5, connect_action_type::tcp_connect)
+
+         // If this failed, we can't continue (error code translation already performed here)
+         if (ec) {
+            return ec;
+         }
+
+         if (st.type == transport_type::tcp_tls) {
+            // Mark the SSL stream as used
+            st.ssl_stream_used = true;
+
+            // Perform the TLS handshake
+            BOOST_REDIS_YIELD(resume_point_, 6, connect_action_type::ssl_handshake)
+
+            // Translate error codes
+            ec = translate_timeout_error(ec, cancel_state, error::ssl_handshake_timeout);
+
+            // Log it
+            if (ec) {
+               log_info(*lgr_, "Connect: SSL handshake failed: ", ec);
+            } else {
+               log_debug(*lgr_, "Connect: SSL handshake succeeded");
+            }
+
+            // If this failed, we can't continue
+            if (ec) {
+               return ec;
+            }
+         }
+
+         // Done
+         return system::error_code();
+      }
+   }
+
+   BOOST_ASSERT(false);
+   return system::error_code();
+}
+
+}  // namespace boost::redis::detail

include/boost/redis/impl/connection.ipp

@@ -1,39 +1,62 @@
-/* Copyright (c) 2018-2023 Marcelo Zimbres Silva (mzimbres@gmail.com)
+/* Copyright (c) 2018-2025 Marcelo Zimbres Silva (mzimbres@gmail.com)
  *
  * Distributed under the Boost Software License, Version 1.0. (See
  * accompanying file LICENSE.txt)
  */
 
 #include <boost/redis/connection.hpp>
+#include <boost/redis/impl/log_to_file.hpp>
+
+#include <cstddef>
+#include <cstdio>
+#include <string_view>
+#include <utility>
 
 namespace boost::redis {
 
-connection::connection(
-   executor_type ex,
-   asio::ssl::context::method method,
-   std::size_t max_read_size)
-: impl_{ex, method, max_read_size}
+logger detail::make_stderr_logger(logger::level lvl, std::string prefix)
+{
+   return logger(lvl, [prefix = std::move(prefix)](logger::level, std::string_view msg) {
+      log_to_file(stderr, msg, prefix.c_str());
+   });
+}
+
+connection::connection(executor_type ex, asio::ssl::context ctx, logger lgr)
+: impl_{std::move(ex), std::move(ctx), std::move(lgr)}
 { }
 
-connection::connection(
-   asio::io_context& ioc,
-   asio::ssl::context::method method,
-   std::size_t max_read_size)
-: impl_{ioc.get_executor(), method, max_read_size}
-{ }
-
-void
-connection::async_run_impl(
+void connection::async_run_impl(
    config const& cfg,
-   logger l,
+   logger&& l,
    asio::any_completion_handler<void(boost::system::error_code)> token)
 {
-   impl_.async_run(cfg, l, std::move(token));
+   // Avoid calling the basic_connection::async_run overload taking a logger
+   // because it generates deprecated messages when building this file
+   impl_.set_stderr_logger(l.lvl, cfg);
+   impl_.async_run(cfg, std::move(token));
 }
 
-void connection::cancel(operation op)
+void connection::async_run_impl(
+   config const& cfg,
+   asio::any_completion_handler<void(boost::system::error_code)> token)
 {
-   impl_.cancel(op);
+   impl_.async_run(cfg, std::move(token));
 }
 
-} // namespace boost::redis
+void connection::async_exec_impl(
+   request const& req,
+   any_adapter&& adapter,
+   asio::any_completion_handler<void(boost::system::error_code, std::size_t)> token)
+{
+   impl_.async_exec(req, std::move(adapter), std::move(token));
+}
+
+void connection::async_receive2_impl(
+   asio::any_completion_handler<void(boost::system::error_code)> token)
+{
+   impl_.async_receive2(std::move(token));
+}
+
+void connection::cancel(operation op) { impl_.cancel(op); }
+
+}  // namespace boost::redis

include/boost/redis/impl/error.ipp

@@ -1,65 +1,92 @@
-/* Copyright (c) 2018-2023 Marcelo Zimbres Silva (mzimbres@gmail.com)
+/* Copyright (c) 2018-2024 Marcelo Zimbres Silva (mzimbres@gmail.com)
  *
  * Distributed under the Boost Software License, Version 1.0. (See
  * accompanying file LICENSE.txt)
  */
 
 #include <boost/redis/error.hpp>
+
 #include <boost/assert.hpp>
 
 namespace boost::redis {
 namespace detail {
 
 struct error_category_impl : system::error_category {
-
    virtual ~error_category_impl() = default;
 
-   auto name() const noexcept -> char const* override
-   {
-      return "boost.redis";
-   }
+   auto name() const noexcept -> char const* override { return "boost.redis"; }
 
    auto message(int ev) const -> std::string override
    {
-      switch(static_cast<error>(ev)) {
-	 case error::invalid_data_type: return "Invalid resp3 type.";
-	 case error::not_a_number: return "Can't convert string to number (maybe forgot to upgrade to RESP3?).";
-	 case error::exceeeds_max_nested_depth: return "Exceeds the maximum number of nested responses.";
-	 case error::unexpected_bool_value: return "Unexpected bool value.";
-	 case error::empty_field: return "Expected field value is empty.";
-	 case error::expects_resp3_simple_type: return "Expects a resp3 simple type.";
-	 case error::expects_resp3_aggregate: return "Expects resp3 aggregate.";
-	 case error::expects_resp3_map: return "Expects resp3 map.";
-	 case error::expects_resp3_set: return "Expects resp3 set.";
-	 case error::nested_aggregate_not_supported: return "Nested aggregate not_supported.";
-	 case error::resp3_simple_error: return "Got RESP3 simple-error.";
-	 case error::resp3_blob_error: return "Got RESP3 blob-error.";
-	 case error::incompatible_size: return "Aggregate container has incompatible size.";
-	 case error::not_a_double: return "Not a double.";
-	 case error::resp3_null: return "Got RESP3 null.";
-	 case error::not_connected: return "Not connected.";
-	 case error::resolve_timeout: return "Resolve timeout.";
-	 case error::connect_timeout: return "Connect timeout.";
-	 case error::pong_timeout: return "Pong timeout.";
-	 case error::ssl_handshake_timeout: return "SSL handshake timeout.";
-	 case error::sync_receive_push_failed: return "Can't receive server push synchronously without blocking.";
-	 case error::incompatible_node_depth: return "Incompatible node depth.";
-	 default: BOOST_ASSERT(false); return "Boost.Redis error.";
+      switch (static_cast<error>(ev)) {
+         case error::invalid_data_type: return "Invalid resp3 type.";
+         case error::not_a_number:
+            return "Can't convert string to number (maybe forgot to upgrade to RESP3?).";
+         case error::exceeeds_max_nested_depth:
+            return "Exceeds the maximum number of nested responses.";
+         case error::unexpected_bool_value:          return "Unexpected bool value.";
+         case error::empty_field:                    return "Expected field value is empty.";
+         case error::expects_resp3_simple_type:      return "Expects a resp3 simple type.";
+         case error::expects_resp3_aggregate:        return "Expects resp3 aggregate.";
+         case error::expects_resp3_map:              return "Expects resp3 map.";
+         case error::expects_resp3_set:              return "Expects resp3 set.";
+         case error::nested_aggregate_not_supported: return "Nested aggregate not_supported.";
+         case error::resp3_simple_error:             return "Got RESP3 simple-error.";
+         case error::resp3_blob_error:               return "Got RESP3 blob-error.";
+         case error::incompatible_size:              return "Aggregate container has incompatible size.";
+         case error::not_a_double:                   return "Not a double.";
+         case error::resp3_null:                     return "Got RESP3 null.";
+         case error::not_connected:                  return "Not connected.";
+         case error::resolve_timeout:                return "Resolve timeout.";
+         case error::connect_timeout:                return "Connect timeout.";
+         case error::pong_timeout:                   return "Pong timeout.";
+         case error::ssl_handshake_timeout:          return "SSL handshake timeout.";
+         case error::sync_receive_push_failed:
+            return "Can't receive server push synchronously without blocking.";
+         case error::incompatible_node_depth: return "Incompatible node depth.";
+         case error::resp3_hello:
+            return "The server response to the setup request sent during connection establishment "
+                   "contains an error.";
+         case error::unix_sockets_unsupported:
+            return "The configuration specified a UNIX socket address, but UNIX sockets are not "
+                   "supported by the system.";
+         case error::unix_sockets_ssl_unsupported:
+            return "The configuration specified UNIX sockets with SSL, which is not supported.";
+         case error::exceeds_maximum_read_buffer_size:
+            return "Reading data from the socket would exceed the maximum size allowed of the read "
+                   "buffer.";
+         case error::write_timeout: return "Timeout while writing data to the server.";
+         case error::sentinel_unix_sockets_unsupported:
+            return "The configuration specified UNIX sockets with Sentinel, which is not "
+                   "supported.";
+         case error::sentinel_resolve_failed:
+            return "No Sentinel could be used to obtain the address of the Redis server.";
+         case error::role_check_failed:
+            return "The contacted server does not have the expected role. "
+                   "This is likely a transient failure caused by a Sentinel failover in progress.";
+         case error::expects_resp3_string:
+            return "Expects a RESP3 string, but got a different data type.";
+         case error::expects_resp3_array:
+            return "Expects a RESP3 array, but got a different data type.";
+         case error::already_running:
+            return "An async_receive2 operation is already running. Only one of such operations "
+                   "might be running at any point in time.";
+         default: BOOST_ASSERT(false); return "Boost.Redis error.";
       }
    }
 };
 
 auto category() -> system::error_category const&
 {
-  static error_category_impl instance;
-  return instance;
+   static error_category_impl instance;
+   return instance;
 }
 
-} // detail
+}  // namespace detail
 
 auto make_error_code(error e) -> system::error_code
 {
-    return system::error_code{static_cast<int>(e), detail::category()};
+   return system::error_code{static_cast<int>(e), detail::category()};
 }
 
-} // boost::redis::detail
+}  // namespace boost::redis

include/boost/redis/impl/exec_fsm.ipp

@@ -0,0 +1,98 @@
+//
+// Copyright (c) 2025 Marcelo Zimbres Silva (mzimbres@gmail.com),
+// Ruben Perez Hidalgo (rubenperez038 at gmail dot com)
+//
+// Distributed under the Boost Software License, Version 1.0. (See accompanying
+// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+//
+
+#ifndef BOOST_REDIS_EXEC_FSM_IPP
+#define BOOST_REDIS_EXEC_FSM_IPP
+
+#include <boost/redis/detail/connection_state.hpp>
+#include <boost/redis/detail/coroutine.hpp>
+#include <boost/redis/detail/exec_fsm.hpp>
+#include <boost/redis/request.hpp>
+
+#include <boost/asio/error.hpp>
+#include <boost/assert.hpp>
+
+namespace boost::redis::detail {
+
+inline bool is_partial_or_terminal_cancel(asio::cancellation_type_t type)
+{
+   return !!(type & (asio::cancellation_type_t::partial | asio::cancellation_type_t::terminal));
+}
+
+inline bool is_total_cancel(asio::cancellation_type_t type)
+{
+   return !!(type & asio::cancellation_type_t::total);
+}
+
+exec_action exec_fsm::resume(
+   bool connection_is_open,
+   connection_state& st,
+   asio::cancellation_type_t cancel_state)
+{
+   switch (resume_point_) {
+      BOOST_REDIS_CORO_INITIAL
+
+      // Check whether the user wants to wait for the connection to
+      // be established.
+      if (elem_->get_request().get_config().cancel_if_not_connected && !connection_is_open) {
+         BOOST_REDIS_YIELD(resume_point_, 1, exec_action_type::immediate)
+         elem_.reset();  // Deallocate memory before finalizing
+         return system::error_code(error::not_connected);
+      }
+
+      // No more immediate errors. Set up the supported cancellation types.
+      // This is required to get partial and total cancellations.
+      // This is a potentially allocating operation, so do it as late as we can.
+      BOOST_REDIS_YIELD(resume_point_, 2, exec_action_type::setup_cancellation)
+
+      // Add the request to the multiplexer
+      st.mpx.add(elem_);
+
+      // Notify the writer task that there is work to do. If the task is not
+      // listening (e.g. it's already writing or the connection is not healthy),
+      // this is a no-op. Since this is sync, no cancellation can happen here.
+      BOOST_REDIS_YIELD(resume_point_, 3, exec_action_type::notify_writer)
+
+      while (true) {
+         // Wait until we get notified. This will return once the request completes,
+         // or upon any kind of cancellation
+         BOOST_REDIS_YIELD(resume_point_, 4, exec_action_type::wait_for_response)
+
+         // If the request has completed (with error or not), we're done
+         if (elem_->is_done()) {
+            // If the request completed successfully and we were configured to do so,
+            // record the changes applied to the pubsub state
+            if (!elem_->get_error())
+               st.tracker.commit_changes(elem_->get_request());
+
+            // Deallocate memory before finalizing
+            exec_action act{elem_->get_error(), elem_->get_read_size()};
+            elem_.reset();
+            return act;
+         }
+
+         // Total cancellation can only be handled if the request hasn't been sent yet.
+         // Partial and terminal cancellation can always be served
+         if (
+            (is_total_cancel(cancel_state) && elem_->is_waiting()) ||
+            is_partial_or_terminal_cancel(cancel_state)) {
+            st.mpx.cancel(elem_);
+            elem_.reset();  // Deallocate memory before finalizing
+            return exec_action{asio::error::operation_aborted};
+         }
+      }
+   }
+
+   // We should never get here
+   BOOST_ASSERT(false);
+   return exec_action{system::error_code()};
+}
+
+}  // namespace boost::redis::detail
+
+#endif

include/boost/redis/impl/exec_one_fsm.ipp

@@ -0,0 +1,95 @@
+//
+// Copyright (c) 2025 Marcelo Zimbres Silva (mzimbres@gmail.com),
+// Ruben Perez Hidalgo (rubenperez038 at gmail dot com)
+//
+// Distributed under the Boost Software License, Version 1.0. (See accompanying
+// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+//
+
+#ifndef BOOST_REDIS_EXEC_ONE_FSM_IPP
+#define BOOST_REDIS_EXEC_ONE_FSM_IPP
+
+#include <boost/redis/adapter/any_adapter.hpp>
+#include <boost/redis/detail/coroutine.hpp>
+#include <boost/redis/detail/exec_one_fsm.hpp>
+#include <boost/redis/detail/read_buffer.hpp>
+#include <boost/redis/impl/is_terminal_cancel.hpp>
+#include <boost/redis/resp3/node.hpp>
+#include <boost/redis/resp3/parser.hpp>
+
+#include <boost/asio/cancellation_type.hpp>
+#include <boost/asio/error.hpp>
+#include <boost/assert.hpp>
+#include <boost/system/error_code.hpp>
+
+#include <cstddef>
+
+namespace boost::redis::detail {
+
+exec_one_action exec_one_fsm::resume(
+   read_buffer& buffer,
+   system::error_code ec,
+   std::size_t bytes_transferred,
+   asio::cancellation_type_t cancel_state)
+{
+   switch (resume_point_) {
+      BOOST_REDIS_CORO_INITIAL
+
+      // Send the request to the server
+      BOOST_REDIS_YIELD(resume_point_, 1, exec_one_action_type::write)
+
+      // Errors and cancellations
+      if (is_terminal_cancel(cancel_state))
+         return system::error_code{asio::error::operation_aborted};
+      if (ec)
+         return ec;
+
+      // If the request didn't expect any response, we're done
+      if (remaining_responses_ == 0u)
+         return system::error_code{};
+
+      // Read responses until we're done
+      buffer.clear();
+      while (true) {
+         // Prepare the buffer to read some data
+         ec = buffer.prepare();
+         if (ec)
+            return ec;
+
+         // Read data
+         BOOST_REDIS_YIELD(resume_point_, 2, exec_one_action_type::read_some)
+
+         // Errors and cancellations
+         if (is_terminal_cancel(cancel_state))
+            return system::error_code{asio::error::operation_aborted};
+         if (ec)
+            return ec;
+
+         // Commit the data into the buffer
+         buffer.commit(bytes_transferred);
+
+         // Consume the data until we run out or all the responses have been read
+         while (resp3::parse(parser_, buffer.get_commited(), adapter_, ec)) {
+            // Check for errors
+            if (ec)
+               return ec;
+
+            // We've finished parsing a response
+            buffer.consume(parser_.get_consumed());
+            parser_.reset();
+
+            // When no more responses remain, we're done.
+            // Don't read ahead, even if more data is available
+            if (--remaining_responses_ == 0u)
+               return system::error_code{};
+         }
+      }
+   }
+
+   BOOST_ASSERT(false);
+   return system::error_code();
+}
+
+}  // namespace boost::redis::detail
+
+#endif

include/boost/redis/impl/flat_tree.ipp

@@ -0,0 +1,248 @@
+//
+// Copyright (c) 2025 Marcelo Zimbres Silva (mzimbres@gmail.com),
+// Nikolai Vladimirov (nvladimirov.work@gmail.com)
+//
+// Distributed under the Boost Software License, Version 1.0. (See accompanying
+// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+//
+
+#include <boost/redis/resp3/flat_tree.hpp>
+#include <boost/redis/resp3/node.hpp>
+#include <boost/redis/resp3/tree.hpp>
+
+#include <boost/assert.hpp>
+#include <boost/throw_exception.hpp>
+
+#include <algorithm>
+#include <cstddef>
+#include <cstring>
+#include <stdexcept>
+#include <string_view>
+
+namespace boost::redis::resp3 {
+
+namespace detail {
+
+// Updates string views by performing pointer arithmetic
+inline void rebase_strings(view_tree& nodes, const char* old_base, const char* new_base)
+{
+   for (auto& nd : nodes) {
+      if (!nd.value.empty()) {
+         const auto offset = nd.value.data() - old_base;
+         BOOST_ASSERT(offset >= 0);
+         nd.value = {new_base + offset, nd.value.size()};
+      }
+   }
+}
+
+// --- Operations in flat_buffer ---
+
+// Compute the new capacity upon reallocation. We always use powers of 2,
+// starting in 512, to prevent many small allocations
+inline std::size_t compute_capacity(std::size_t current, std::size_t requested)
+{
+   std::size_t res = (std::max)(current, static_cast<std::size_t>(512u));
+   while (res < requested)
+      res *= 2u;
+   return res;
+}
+
+// Copy construction
+inline flat_buffer copy_construct(const flat_buffer& other)
+{
+   flat_buffer res{{}, other.size, 0u, 0u};
+
+   if (other.size > 0u) {
+      const std::size_t capacity = compute_capacity(0u, other.size);
+      res.data.reset(new char[capacity]);
+      res.capacity = capacity;
+      res.reallocs = 1u;
+      std::copy(other.data.get(), other.data.get() + other.size, res.data.get());
+   }
+
+   return res;
+}
+
+// Copy assignment
+inline void copy_assign(flat_buffer& buff, const flat_buffer& other)
+{
+   // Make space if required
+   if (buff.capacity < other.size) {
+      const std::size_t capacity = compute_capacity(buff.capacity, other.size);
+      buff.data.reset(new char[capacity]);
+      buff.capacity = capacity;
+      ++buff.reallocs;
+   }
+
+   // Copy the contents
+   std::copy(other.data.get(), other.data.get() + other.size, buff.data.get());
+   buff.size = other.size;
+}
+
+// Grows the buffer until reaching a target size.
+// Might rebase the strings in nodes
+inline void grow(flat_buffer& buff, std::size_t new_capacity, view_tree& nodes)
+{
+   if (new_capacity <= buff.capacity)
+      return;
+
+   // Compute the actual capacity that we will be using
+   new_capacity = compute_capacity(buff.capacity, new_capacity);
+
+   // Allocate space
+   std::unique_ptr<char[]> new_buffer{new char[new_capacity]};
+
+   // Copy any data into the newly allocated space
+   const char* data_before = buff.data.get();
+   char* data_after = new_buffer.get();
+   std::copy(data_before, data_before + buff.size, data_after);
+
+   // Update the string views so they don't dangle
+   rebase_strings(nodes, data_before, data_after);
+
+   // Replace the buffer. Note that size hasn't changed here
+   buff.data = std::move(new_buffer);
+   buff.capacity = new_capacity;
+   ++buff.reallocs;
+}
+
+// Erases the first num_bytes bytes from the buffer by moving
+// the remaining bytes forward. Rebases the strings in nodes as required.
+inline void erase_first(flat_buffer& buff, std::size_t num_bytes, view_tree& nodes)
+{
+   BOOST_ASSERT(num_bytes <= buff.size);
+   if (num_bytes > 0u) {
+      // If we have any data to move, we should always have a buffer
+      BOOST_ASSERT(buff.data.get() != nullptr);
+
+      // Record the old base
+      const char* old_base = buff.data.get() + num_bytes;
+
+      // Move all that we're gonna keep to the start of the buffer
+      auto bytes_left = buff.size - num_bytes;
+      std::memmove(buff.data.get(), old_base, bytes_left);
+
+      // Rebase strings
+      rebase_strings(nodes, old_base, buff.data.get());
+   }
+}
+
+// Appends a string to the buffer.
+// Might rebase the string in nodes, but doesn't append any new node.
+inline std::string_view append(flat_buffer& buff, std::string_view value, view_tree& nodes)
+{
+   // If there is nothing to copy, do nothing
+   if (value.empty())
+      return value;
+
+   // Make space for the new string
+   const std::size_t new_size = buff.size + value.size();
+   grow(buff, new_size, nodes);
+
+   // Copy the new value
+   const std::size_t offset = buff.size;
+   std::copy(value.data(), value.data() + value.size(), buff.data.get() + offset);
+   buff.size = new_size;
+   return {buff.data.get() + offset, value.size()};
+}
+
+}  // namespace detail
+
+flat_tree::flat_tree(flat_tree const& other)
+: data_{detail::copy_construct(other.data_)}
+, view_tree_{other.view_tree_}
+, total_msgs_{other.total_msgs_}
+, node_tmp_offset_{other.node_tmp_offset_}
+, data_tmp_offset_{other.data_tmp_offset_}
+{
+   detail::rebase_strings(view_tree_, other.data_.data.get(), data_.data.get());
+}
+
+flat_tree& flat_tree::operator=(const flat_tree& other)
+{
+   if (this != &other) {
+      // Copy the data
+      detail::copy_assign(data_, other.data_);
+
+      // Copy the nodes
+      view_tree_ = other.view_tree_;
+      detail::rebase_strings(view_tree_, other.data_.data.get(), data_.data.get());
+
+      // Copy the other fields
+      total_msgs_ = other.total_msgs_;
+      node_tmp_offset_ = other.node_tmp_offset_;
+      data_tmp_offset_ = other.data_tmp_offset_;
+   }
+
+   return *this;
+}
+
+void flat_tree::reserve(std::size_t bytes, std::size_t nodes)
+{
+   // Space for the strings
+   detail::grow(data_, bytes, view_tree_);
+
+   // Space for the nodes
+   view_tree_.reserve(nodes);
+}
+
+void flat_tree::clear() noexcept
+{
+   // Discard everything except for the tmp area
+   view_tree_.erase(view_tree_.begin(), view_tree_.begin() + node_tmp_offset_);
+   node_tmp_offset_ = 0u;
+
+   // Do the same for the data area
+   detail::erase_first(data_, data_tmp_offset_, view_tree_);
+   data_tmp_offset_ = 0u;
+
+   // We now have no messages
+   total_msgs_ = 0u;
+}
+
+void flat_tree::push(node_view const& nd)
+{
+   // Add the string
+   const std::string_view str = detail::append(data_, nd.value, view_tree_);
+
+   // Add the node
+   view_tree_.push_back({
+      nd.data_type,
+      nd.aggregate_size,
+      nd.depth,
+      str,
+   });
+}
+
+void flat_tree::notify_init()
+{
+   // Discard any data in the tmp area, as it belongs to an operation that never finished
+   BOOST_ASSERT(node_tmp_offset_ <= view_tree_.size());
+   BOOST_ASSERT(data_tmp_offset_ <= data_.size);
+   view_tree_.resize(node_tmp_offset_);
+   data_.size = data_tmp_offset_;
+}
+
+void flat_tree::notify_done()
+{
+   ++total_msgs_;
+   node_tmp_offset_ = view_tree_.size();
+   data_tmp_offset_ = data_.size;
+}
+
+const node_view& flat_tree::at(std::size_t i) const
+{
+   if (i >= size())
+      BOOST_THROW_EXCEPTION(std::out_of_range("flat_tree::at"));
+   return view_tree_[i];
+}
+
+bool operator==(flat_tree const& a, flat_tree const& b)
+{
+   // data is already taken into account by comparing the nodes.
+   // Only committed nodes should be taken into account.
+   return a.size() == b.size() && std::equal(a.begin(), a.end(), b.begin()) &&
+          a.get_total_msgs() == b.get_total_msgs();
+}
+
+}  // namespace boost::redis::resp3

include/boost/redis/impl/ignore.ipp

@@ -1,4 +1,4 @@
-/* Copyright (c) 2018-2023 Marcelo Zimbres Silva (mzimbres@gmail.com)
+/* Copyright (c) 2018-2024 Marcelo Zimbres Silva (mzimbres@gmail.com)
  *
  * Distributed under the Boost Software License, Version 1.0. (See
  * accompanying file LICENSE.txt)
@@ -6,7 +6,6 @@
 
 #include <boost/redis/ignore.hpp>
 
-namespace boost::redis
-{
+namespace boost::redis {
 ignore_t ignore;
 }

include/boost/redis/impl/is_terminal_cancel.hpp

@@ -0,0 +1,23 @@
+//
+// Copyright (c) 2025 Marcelo Zimbres Silva (mzimbres@gmail.com),
+// Ruben Perez Hidalgo (rubenperez038 at gmail dot com)
+//
+// Distributed under the Boost Software License, Version 1.0. (See accompanying
+// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+//
+
+#ifndef BOOST_REDIS_IS_TERMINAL_CANCEL_HPP
+#define BOOST_REDIS_IS_TERMINAL_CANCEL_HPP
+
+#include <boost/asio/cancellation_type.hpp>
+
+namespace boost::redis::detail {
+
+constexpr bool is_terminal_cancel(asio::cancellation_type_t cancel_state)
+{
+   return (cancel_state & asio::cancellation_type_t::terminal) != asio::cancellation_type_t::none;
+}
+
+}  // namespace boost::redis::detail
+
+#endif

include/boost/redis/impl/log_to_file.hpp

@@ -0,0 +1,37 @@
+//
+// Copyright (c) 2025 Marcelo Zimbres Silva (mzimbres@gmail.com),
+// Ruben Perez Hidalgo (rubenperez038 at gmail dot com)
+//
+// Distributed under the Boost Software License, Version 1.0. (See accompanying
+// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+//
+
+#ifndef BOOST_REDIS_LOG_TO_STDERR_HPP
+#define BOOST_REDIS_LOG_TO_STDERR_HPP
+
+#include <algorithm>
+#include <cstddef>
+#include <cstdio>
+#include <string_view>
+
+namespace boost::redis::detail {
+
+// Shared by several ipp files
+inline void log_to_file(FILE* f, std::string_view msg, const char* prefix = "(Boost.Redis) ")
+{
+   // If the message is empty, data() might return a null pointer
+   const char* msg_ptr = msg.empty() ? "" : msg.data();
+
+   // Precision should be an int when passed to fprintf. Technically,
+   // message could be larger than INT_MAX. Impose a sane limit on message sizes
+   // to prevent memory problems
+   auto precision = static_cast<int>((std::min)(msg.size(), static_cast<std::size_t>(0xffffu)));
+
+   // Log the message. None of our messages should contain NULL bytes, so this should be OK.
+   // We choose fprintf over std::clog because it's safe in multi-threaded environments.
+   std::fprintf(f, "%s%.*s\n", prefix, precision, msg_ptr);
+}
+
+}  // namespace boost::redis::detail
+
+#endif

include/boost/redis/impl/log_utils.hpp

@@ -0,0 +1,110 @@
+/* Copyright (c) 2018-2025 Marcelo Zimbres Silva (mzimbres@gmail.com)
+ *
+ * Distributed under the Boost Software License, Version 1.0. (See
+ * accompanying file LICENSE.txt)
+ */
+
+#ifndef BOOST_REDIS_LOG_UTILS_HPP
+#define BOOST_REDIS_LOG_UTILS_HPP
+
+#include <boost/redis/config.hpp>
+#include <boost/redis/logger.hpp>
+
+#include <boost/core/ignore_unused.hpp>
+#include <boost/system/error_code.hpp>
+
+#include <cstddef>
+#include <string>
+#include <string_view>
+#include <type_traits>
+
+namespace boost::redis::detail {
+
+// Internal trait that defines how to log different types.
+// The base template applies to types convertible to string_view
+template <class T>
+struct log_traits {
+   // log should convert the input value to string and append it to the supplied buffer
+   static inline void log(std::string& to, std::string_view value) { to += value; }
+};
+
+// Formatting size_t and error codes is shared between almost all FSMs, so it's defined here.
+// Support for types used only in one FSM should be added in the relevant FSM file.
+template <>
+struct log_traits<std::size_t> {
+   static inline void log(std::string& to, std::size_t value) { to += std::to_string(value); }
+};
+
+template <>
+struct log_traits<system::error_code> {
+   static inline void log(std::string& to, system::error_code value)
+   {
+      // Using error_code::what() includes any source code info
+      // that the error may contain, making the messages too long.
+      // This implementation was taken from error_code::what()
+      to += value.message();
+      to += " [";
+      to += value.to_string();
+      to += ']';
+   }
+};
+
+template <>
+struct log_traits<address> {
+   static inline void log(std::string& to, const address& value)
+   {
+      to += value.host;
+      to += ':';
+      to += value.port;
+   }
+};
+
+template <class... Args>
+void format_log_args(std::string& to, const Args&... args)
+{
+   auto dummy = {(log_traits<Args>::log(to, args), 0)...};
+   ignore_unused(dummy);
+}
+
+// Logs a message with the specified severity to the logger.
+// Formatting won't be performed if the logger's level is inferior to lvl.
+// args are stringized using log_traits, and concatenated.
+template <class Arg0, class... Rest>
+void log(buffered_logger& to, logger::level lvl, const Arg0& arg0, const Rest&... arg_rest)
+{
+   // Severity check
+   if (to.lgr.lvl < lvl)
+      return;
+
+   // Optimization: if we get passed a single string, don't copy it to the buffer
+   if constexpr (sizeof...(Rest) == 0u && std::is_convertible_v<Arg0, std::string_view>) {
+      to.lgr.fn(lvl, arg0);
+   } else {
+      to.buffer.clear();
+      format_log_args(to.buffer, arg0, arg_rest...);
+      to.lgr.fn(lvl, to.buffer);
+   }
+}
+
+// Shorthand for each log level we use
+template <class... Args>
+void log_debug(buffered_logger& to, const Args&... args)
+{
+   log(to, logger::level::debug, args...);
+}
+
+template <class... Args>
+void log_info(buffered_logger& to, const Args&... args)
+{
+   log(to, logger::level::info, args...);
+}
+
+template <class... Args>
+void log_err(buffered_logger& to, const Args&... args)
+{
+   log(to, logger::level::err, args...);
+}
+
+}  // namespace boost::redis::detail
+
+#endif  // BOOST_REDIS_LOGGER_HPP