More code review changes.

Moves read_buffer memory reservation to the connection's constructor
Makes read_buffer memory reservation size be a power of 2

.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 +131,159 @@ 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: ''
+
+          - toolset: gcc-11
+            install: g++-11
+            container: ubuntu:22.04
+            cxxstd: '20'
+            build-type: 'Release'
+            ldflags: ''
+
+          - toolset: clang-11
+            install: clang-11
+            container: ubuntu:22.04
+            cxxstd: '17'
+            build-type: 'Debug'
+            ldflags: ''
+
+          - toolset: clang-11
+            install: clang-11
+            container: ubuntu:22.04
+            cxxstd: '20'
+            build-type: 'Debug'
+            ldflags: ''
+
+          - toolset: clang-13
+            install: clang-13
+            container: ubuntu:22.04
+            cxxstd: '17'
+            build-type: 'Release'
+            ldflags: ''
+
+          - toolset: clang-13
+            install: clang-13
+            container: ubuntu:22.04
+            cxxstd: '20'
+            build-type: 'Release'
+            ldflags: ''
+
+          - 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++'
+
+          - 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++'
+          
+          - 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'
+
+          - 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
+          
+          - 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'
+
+    runs-on: ubuntu-latest
     env:
       CXXFLAGS: ${{matrix.cxxflags}} -Wall -Wextra
       LDFLAGS:  ${{matrix.ldflags}}
       CMAKE_BUILD_PARALLEL_LEVEL: 4
+    
     steps:
     - name: Checkout
-      uses: actions/checkout@v3
-
+      uses: actions/checkout@v4
+    
+    - name: Set up the required containers
+      run: |
+        IMAGE=${{ matrix.container }} 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 +298,32 @@ 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 +334,24 @@ 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 +19,76 @@ 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
+  )
+
+  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

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 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 +1,10 @@
+* xref:index.adoc[Introduction]
+* xref:requests_responses.adoc[]
+* xref:serialization.adoc[]
+* xref:logging.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/changelog.adoc

@@ -0,0 +1,397 @@
+//
+// 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 1.88
+
+* (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_resolve_with_sentinel.cpp[cpp20_resolve_with_sentinel.cpp]: Shows how to resolve a master address using sentinels.
+* {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 +1,143 @@
+//
+// 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] 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 (must support RESP3).
+* 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_receive`] 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) -> net::awaitable<void>
+{
+   request req;
+   req.push("SUBSCRIBE", "channel");
+
+   generic_response resp;
+   conn->set_receive_response(resp);
+
+   // Loop while reconnection is enabled
+   while (conn->will_reconnect()) {
+
+      // Reconnect to channels.
+      co_await conn->async_exec(req, ignore);
+
+      // Loop reading Redis pushes.
+      for (;;) {
+         error_code ec;
+         co_await conn->async_receive(resp, net::redirect_error(net::use_awaitable, ec));
+         if (ec)
+            break; // Connection lost, break so we can reconnect to channels.
+
+         // Use the response resp in some way and then clear it.
+         ...
+
+         consume_one(resp);
+      }
+   }
+}
+----
+
+== Further reading
+
+Here is a list of topics that you might be interested in:
+
+* 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 +1,90 @@
+//
+// 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/config.adoc[`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/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[`basic_node`]
+
+xref:reference:boost/redis/resp3/node.adoc[`node`]
+
+xref:reference:boost/redis/resp3/node_view.adoc[`node_view`]
+
+xref:reference:boost/redis/resp3/boost_redis_to_bulk-08.adoc[`boost_redis_to_bulk`]
+
+xref:reference:boost/redis/resp3/type.adoc[`type`]
+
+xref:reference:boost/redis/resp3/is_aggregate.adoc[`is_aggregate`]
+
+
+|
+
+xref:reference:boost/redis/adapter/adapt2.adoc[`adapter::adapt2`]
+
+xref:reference:boost/redis/resp3/parser.adoc[`parser`]
+
+xref:reference:boost/redis/resp3/parse.adoc[`parse`]
+
+|===

doc/modules/ROOT/pages/requests_responses.adoc

@@ -0,0 +1,302 @@
+//
+// 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[`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.push("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].
+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`: 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/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

@@ -10,6 +10,9 @@ 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)
@@ -26,6 +29,7 @@ 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_example(cpp20_subscriber 20)
 make_example(cpp20_streams 20)
@@ -46,4 +50,13 @@ 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 +1,102 @@
+//
+// 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
+{
+   if (argc != 3) {
+      std::cerr << "Usage: " << argv[0] << " <server-host> <server-port>\n";
+      exit(1);
+   }
+
+   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
+      redis::config cfg;
+      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

@@ -5,26 +5,26 @@
  */
 
 #include <boost/redis/connection.hpp>
-#include <boost/asio/deferred.hpp>
-#include <boost/asio/signal_set.hpp>
+
 #include <boost/asio/co_spawn.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/redirect_error.hpp>
+#include <boost/asio/signal_set.hpp>
+
 #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;
@@ -40,8 +40,7 @@ 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>
+auto receiver(std::shared_ptr<connection> conn) -> awaitable<void>
 {
    request req;
    req.push("SUBSCRIBE", "channel");
@@ -50,33 +49,30 @@ receiver(std::shared_ptr<connection> conn) -> awaitable<void>
    conn->set_receive_response(resp);
 
    while (conn->will_reconnect()) {
-
       // Subscribe to channels.
-      co_await conn->async_exec(req, ignore, deferred);
+      co_await conn->async_exec(req, ignore);
 
       // 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;
+            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();
       }
    }
 }
 
 // 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, ignore);
       msg.erase(0, n);
    }
 }
@@ -90,7 +86,7 @@ auto co_main(config cfg) -> awaitable<void>
 
    co_spawn(ex, receiver(conn), detached);
    co_spawn(ex, publisher(stream, conn), detached);
-   conn->async_run(cfg, {}, consign(detached, conn));
+   conn->async_run(cfg, consign(detached, conn));
 
    signal_set sig_set{ex, SIGINT, SIGTERM};
    co_await sig_set.async_wait();
@@ -98,11 +94,11 @@ 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 +1,17 @@
-/* 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/detached.hpp>
+
+#include <iostream>
 #include <map>
 #include <vector>
-#include <iostream>
 
 #if defined(BOOST_ASIO_HAS_CO_AWAIT)
 
@@ -22,36 +23,51 @@ 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 +80,22 @@ 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 +105,41 @@ 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 +5,18 @@
  */
 
 #include <boost/redis/connection.hpp>
-#include <boost/asio/deferred.hpp>
-#include <boost/asio/signal_set.hpp>
+
+#include <boost/asio/co_spawn.hpp>
 #include <boost/asio/detached.hpp>
 #include <boost/asio/redirect_error.hpp>
-#include <boost/asio/co_spawn.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 +24,8 @@ 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 +33,7 @@ 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 +46,7 @@ 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 +60,11 @@ 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

@@ -5,9 +5,11 @@
  */
 
 #include <boost/redis/connection.hpp>
-#include <boost/asio/use_awaitable.hpp>
-#include <boost/asio/redirect_error.hpp>
+
 #include <boost/asio/detached.hpp>
+#include <boost/asio/redirect_error.hpp>
+#include <boost/asio/use_awaitable.hpp>
+
 #include <iostream>
 
 #if defined(BOOST_ASIO_HAS_CO_AWAIT)
@@ -21,8 +23,7 @@ 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); }
+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.
@@ -43,12 +44,13 @@ auto resolve_master_address(std::vector<address> const& addresses) -> asio::awai
       // 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));
+      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{
+            std::get<0>(resp).value().value().at(0),
+            std::get<0>(resp).value().value().at(1)};
    }
 
    co_return address{};
@@ -58,18 +60,17 @@ 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
+   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;
+   std::clog << "Host: " << ep.host << "\n"
+             << "Port: " << ep.port << "\n"
+             << std::flush;
 }
 
-#endif // defined(BOOST_ASIO_HAS_CO_AWAIT)
+#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

@@ -6,14 +6,15 @@
 
 #include <boost/redis/connection.hpp>
 #include <boost/redis/logger.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/detached.hpp>
 #include <boost/asio/redirect_error.hpp>
 #include <boost/asio/signal_set.hpp>
+#include <boost/asio/use_awaitable.hpp>
+
 #include <iostream>
 
 #if defined(BOOST_ASIO_HAS_CO_AWAIT)
@@ -29,7 +30,7 @@ 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.
  *
@@ -48,8 +49,7 @@ 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");
@@ -59,9 +59,8 @@ receiver(std::shared_ptr<connection> conn) -> asio::awaitable<void>
 
    // Loop while reconnection is enabled
    while (conn->will_reconnect()) {
-
       // Reconnect to the channels.
-      co_await conn->async_exec(req, ignore, asio::deferred);
+      co_await conn->async_exec(req, ignore);
 
       // Loop reading Redis pushs messages.
       for (error_code ec;;) {
@@ -73,13 +72,10 @@ receiver(std::shared_ptr<connection> conn) -> asio::awaitable<void>
          }
 
          if (ec)
-            break; // Connection lost, break so we can reconnect to channels.
+            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;
+         std::cout << resp.value().at(1).value << " " << resp.value().at(2).value << " "
+                   << resp.value().at(3).value << std::endl;
 
          consume_one(resp);
       }
@@ -91,7 +87,7 @@ 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 +95,4 @@ 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_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 +1,114 @@
+/* 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 <cstddef>
+#include <functional>
+#include <string_view>
+#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
+   {
+      using namespace boost::redis::adapter;
+      return [adapter2 = boost_redis_adapt(resp)](
+                  any_adapter::parse_event ev,
+                  resp3::node_view const& nd,
+                  system::error_code& ec) mutable {
+         switch (ev) {
+            case parse_event::init: adapter2.on_init(); break;
+            case parse_event::node: adapter2.on_node(nd, ec); break;
+            case parse_event::done: adapter2.on_done(); break;
+         }
+      };
+   }
+
+   /// 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 boost::redis
+
+#endif

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

@@ -1,4 +1,4 @@
-/* Copyright (c) 2018-2023 Marcelo Zimbres Silva (mzimbres@gmail.com)
+/* Copyright (c) 2018-2024 Marcelo Zimbres Silva (mzimbres@gmail.com)
  *
  * Distributed under the Boost Software License, Version 1.0. (See
  * accompanying file LICENSE.txt)
@@ -7,80 +7,133 @@
 #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/node.hpp>
+#include <boost/redis/resp3/serialization.hpp>
+#include <boost/redis/resp3/type.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);
 }
 
 //================================================
@@ -91,18 +144,32 @@ 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)}});
+            result_->value().push_back({
+               nd.data_type,
+               nd.aggregate_size,
+               nd.depth,
+               std::string{std::cbegin(nd.value), std::cend(nd.value)}
+            });
       }
    }
 };
@@ -113,16 +180,24 @@ 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 +211,20 @@ 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 +234,13 @@ 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 +251,12 @@ 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 +268,34 @@ 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 +306,20 @@ 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 +330,16 @@ 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 +355,7 @@ 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 +364,23 @@ 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 +388,84 @@ 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 +474,41 @@ 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 +520,7 @@ 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 +528,25 @@ 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 +556,18 @@ 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 +78,35 @@ 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>;
+   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... 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 +7,21 @@
 #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/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 +30,7 @@ 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}; }
 };
 
@@ -65,27 +65,29 @@ struct result_traits<result<std::vector<resp3::basic_node<String>, Allocator>>>
 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 +96,16 @@ 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 +119,73 @@ 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 +8,16 @@
 #ifndef BOOST_REDIS_ADAPTER_RESULT_HPP
 #define BOOST_REDIS_ADAPTER_RESULT_HPP
 
-#include <boost/redis/resp3/type.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 +43,30 @@ 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.");
+      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);
 }
 
-} // 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 +7,14 @@
 #ifndef BOOST_REDIS_CONFIG_HPP
 #define BOOST_REDIS_CONFIG_HPP
 
-#include <string>
 #include <chrono>
+#include <limits>
 #include <optional>
+#include <string>
 
-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 +22,89 @@ struct address {
    std::string port = "6379";
 };
 
-/** @brief Configure parameters used by the connection classes
- *  @ingroup high-level-api
- */
+/// Configure parameters used by the connection classes.
 struct config {
    /// Uses SSL instead of a plain connection.
    bool use_ssl = false;
 
-   /// Address of the Redis server.
+   /// For TCP connections, hostname and port of the Redis server.
    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`.
     */
-   std::string username;
+   std::string unix_socket;
+
+   /** @brief Username passed to the `HELLO` command.
+    * If left empty `HELLO` will be sent without authentication parameters.
+    */
+   std::string username = "default";
 
    /** @brief Password passed to the
-    * [HELLO](https://redis.io/commands/hello/) command.  If left
+    * `HELLO` command.  If left
     * empty `HELLO` will be sent without authentication parameters.
     */
    std::string password;
 
-   /// Client name parameter of the [HELLO](https://redis.io/commands/hello/) command.
+   /// Client name parameter of the `HELLO` command.
    std::string clientname = "Boost.Redis";
 
-   /// Database that will be passed to the [SELECT](https://redis.io/commands/hello/) command.
+   /// Database that will be passed to the `SELECT` command.
    std::optional<int> database_index = 0;
 
-   /// Message used by the health-checker in `boost::redis::connection::async_run`.
+   /// Message used by the health-checker in @ref boost::redis::basic_connection::async_run.
    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.
+   /// Time span that the resolve operation is allowed to elapse.
    std::chrono::steady_clock::duration resolve_timeout = std::chrono::seconds{10};
 
-   /// Time the connect operation is allowed to last.
+   /// Time span that the connect operation is allowed to elapse.
    std::chrono::steady_clock::duration connect_timeout = std::chrono::seconds{10};
 
-   /// Time the SSL handshake operation is allowed to last.
+   /// Time span that the SSL handshake operation is allowed to elapse.
    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 pass zero as duration.
     */
    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.
     */
    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.
+    */
+   std::size_t max_read_size = (std::numeric_limits<std::size_t>::max)();
+
+   /** @brief read_buffer_append_size
+    *
+    * 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.
+    */
+   std::size_t read_buffer_append_size = 4096;
 };
 
-} // boost::redis
+}  // namespace boost::redis
 
-#endif // BOOST_REDIS_CONFIG_HPP
+#endif  // BOOST_REDIS_CONFIG_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_logger.hpp

@@ -0,0 +1,54 @@
+/* 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_CONNECTION_LOGGER_HPP
+#define BOOST_REDIS_CONNECTION_LOGGER_HPP
+
+#include <boost/redis/detail/reader_fsm.hpp>
+#include <boost/redis/logger.hpp>
+#include <boost/redis/response.hpp>
+
+#include <boost/asio/ip/tcp.hpp>
+#include <boost/system/error_code.hpp>
+
+#include <string_view>
+
+namespace boost::redis::detail {
+
+// Wraps a logger and a string buffer for re-use, and provides
+// utility functions to format the log messages that we use.
+// The long-term trend will be moving most of this class to finite state
+// machines as we write them
+class connection_logger {
+   logger logger_;
+   std::string msg_;
+
+public:
+   connection_logger(logger&& logger) noexcept
+   : logger_(std::move(logger))
+   { }
+
+   void reset(logger&& logger) { logger_ = std::move(logger); }
+
+   void on_resolve(system::error_code const& ec, asio::ip::tcp::resolver::results_type const& res);
+   void on_connect(system::error_code const& ec, asio::ip::tcp::endpoint const& ep);
+   void on_connect(system::error_code const& ec, std::string_view unix_socket_ep);
+   void on_ssl_handshake(system::error_code const& ec);
+   void on_write(system::error_code const& ec, std::size_t n);
+   void on_fsm_resume(reader_fsm::action const& action);
+   void on_hello(system::error_code const& ec, generic_response const& resp);
+   void log(logger::level lvl, std::string_view msg);
+   void log(logger::level lvl, std::string_view op, system::error_code const& ec);
+   void trace(std::string_view message) { log(logger::level::debug, message); }
+   void trace(std::string_view op, system::error_code const& ec)
+   {
+      log(logger::level::debug, op, ec);
+   }
+};
+
+}  // namespace boost::redis::detail
+
+#endif  // BOOST_REDIS_LOGGER_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 +1,72 @@
+//
+// 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 {
+
+// 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
+   cancel_run,          // Cancel the connection's run operation
+};
+
+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};
+   multiplexer* mpx_{nullptr};
+   std::shared_ptr<multiplexer::elem> elem_;
+
+public:
+   exec_fsm(multiplexer& mpx, std::shared_ptr<multiplexer::elem> elem) noexcept
+   : mpx_(&mpx)
+   , elem_(std::move(elem))
+   { }
+
+   exec_action resume(bool connection_is_open, 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

@@ -1,4 +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)
@@ -7,94 +7,114 @@
 #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/adapter/any_adapter.hpp>
+#include <boost/redis/config.hpp>
+#include <boost/redis/detail/connection_logger.hpp>
+#include <boost/redis/operation.hpp>
 #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 <boost/asio/steady_timer.hpp>
+
 #include <chrono>
 
 namespace boost::redis::detail {
 
-template <class HealthChecker, class Connection, class Logger>
+template <class HealthChecker, class ConnectionImpl>
 class ping_op {
 public:
    HealthChecker* checker_ = nullptr;
-   Connection* conn_ = nullptr;
-   Logger logger_;
+   ConnectionImpl* conn_ = nullptr;
    asio::coroutine coro_{};
 
    template <class Self>
    void operator()(Self& self, system::error_code ec = {}, std::size_t = 0)
    {
-      BOOST_ASIO_CORO_REENTER (coro_) for (;;)
+      BOOST_ASIO_CORO_REENTER(coro_) for (;;)
       {
+         if (checker_->ping_interval_ == std::chrono::seconds::zero()) {
+            conn_->logger_.trace("ping_op (1): timeout disabled.");
+            BOOST_ASIO_CORO_YIELD
+            asio::post(std::move(self));
+            self.complete({});
+            return;
+         }
+
          if (checker_->checker_has_exited_) {
-            logger_.trace("ping_op: checker has exited. Exiting ...");
+            conn_->logger_.trace("ping_op (2): checker has exited.");
             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).");
+         conn_->async_exec(
+            checker_->req_,
+            any_adapter{checker_->resp_},
+            std::move(self));
+         if (ec) {
+            conn_->logger_.trace("ping_op (3)", ec);
             checker_->wait_timer_.cancel();
-            self.complete(!!ec ? ec : asio::error::operation_aborted);
+            self.complete(ec);
             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);
+         if (ec) {
+            conn_->logger_.trace("ping_op (4)", ec);
+            self.complete(ec);
             return;
          }
       }
    }
 };
 
-template <class HealthChecker, class Connection, class Logger>
+template <class HealthChecker, class Connection>
 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 (;;)
+      BOOST_ASIO_CORO_REENTER(coro_) for (;;)
       {
+         if (checker_->ping_interval_ == std::chrono::seconds::zero()) {
+            conn_->logger_.trace("check_timeout_op (1): timeout disabled.");
+            BOOST_ASIO_CORO_YIELD
+            asio::post(std::move(self));
+            self.complete({});
+            return;
+         }
+
          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);
+         if (ec) {
+            conn_->logger_.trace("check_timeout_op (2)", ec);
+            self.complete(ec);
             return;
          }
 
          if (checker_->resp_.has_error()) {
-            logger_.trace("check-timeout-op: Response error. Exiting ...");
+            // TODO: Log the error.
+            conn_->logger_.trace("check_timeout_op (3): Response error.");
             self.complete({});
             return;
          }
 
          if (checker_->resp_.value().empty()) {
-            logger_.trace("check-timeout-op: Response has no value. Exiting ...");
+            conn_->logger_.trace("check_timeout_op (4): pong timeout.");
             checker_->ping_timer_.cancel();
             conn_->cancel(operation::run);
             checker_->checker_has_exited_ = true;
@@ -109,65 +129,13 @@ public:
    }
 };
 
-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>;
+   using timer_type = asio::basic_waitable_timer<
+      std::chrono::steady_clock,
+      asio::wait_traits<std::chrono::steady_clock>,
+      Executor>;
 
 public:
    health_checker(Executor ex)
@@ -184,60 +152,36 @@ public:
       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{})
+   void cancel()
    {
-      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);
+      ping_timer_.cancel();
+      wait_timer_.cancel();
    }
 
-   std::size_t cancel(operation op)
+   template <class ConnectionImpl, class CompletionToken>
+   auto async_ping(ConnectionImpl& conn, CompletionToken token)
    {
-      switch (op) {
-         case operation::health_check:
-         case operation::all:
-            ping_timer_.cancel();
-            wait_timer_.cancel();
-            break;
-         default: /* ignore */;
-      }
+      return asio::async_compose<CompletionToken, void(system::error_code)>(
+         ping_op<health_checker, ConnectionImpl>{this, &conn},
+         token,
+         conn,
+         ping_timer_);
+   }
 
-      return 0;
+   template <class Connection, class CompletionToken>
+   auto async_check_timeout(Connection& conn, CompletionToken token)
+   {
+      checker_has_exited_ = false;
+      return asio::async_compose<CompletionToken, void(system::error_code)>(
+         check_timeout_op<health_checker, Connection>{this, &conn},
+         token,
+         conn,
+         wait_timer_);
    }
 
 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;
+   template <class, class> friend class ping_op;
+   template <class, class> friend class check_timeout_op;
 
    timer_type ping_timer_;
    timer_type wait_timer_;
@@ -247,6 +191,6 @@ private:
    bool checker_has_exited_ = false;
 };
 
-} // boost::redis::detail
+}  // namespace boost::redis::detail
 
-#endif // BOOST_REDIS_HEALTH_CHECKER_HPP
+#endif  // BOOST_REDIS_HEALTH_CHECKER_HPP

include/boost/redis/detail/helper.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)
@@ -9,8 +9,7 @@
 
 #include <boost/asio/cancellation_type.hpp>
 
-namespace boost::redis::detail
-{
+namespace boost::redis::detail {
 
 template <class T>
 auto is_cancelled(T const& self)
@@ -18,20 +17,18 @@ 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_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;\
+#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
+}  // namespace boost::redis::detail
 
-#endif // BOOST_REDIS_HELPER_HPP
+#endif  // BOOST_REDIS_HELPER_HPP

include/boost/redis/detail/multiplexer.hpp

@@ -0,0 +1,198 @@
+/* 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/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 <algorithm>
+#include <deque>
+#include <functional>
+#include <memory>
+#include <optional>
+#include <string_view>
+#include <utility>
+
+namespace boost::redis {
+
+class request;
+
+namespace detail {
+
+using tribool = std::optional<bool>;
+
+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_; }
+
+   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_;
+   };
+
+   auto remove(std::shared_ptr<elem> const& ptr) -> bool;
+
+   [[nodiscard]]
+   auto prepare_write() -> std::size_t;
+
+   // Returns the number of requests that have been released because
+   // they don't have a response e.g. SUBSCRIBE.
+   auto commit_write() -> std::size_t;
+
+   // If the tribool contains no value more data is needed, otherwise
+   // if the value is true the message consumed is a push.
+   [[nodiscard]]
+   auto consume_next(std::string_view data, system::error_code& ec)
+      -> std::pair<tribool, std::size_t>;
+
+   auto add(std::shared_ptr<elem> const& ptr) -> void;
+   auto reset() -> void;
+
+   [[nodiscard]]
+   auto const& get_parser() const noexcept
+   {
+      return parser_;
+   }
+
+   //[[nodiscard]]
+   auto cancel_waiting() -> std::size_t;
+
+   //[[nodiscard]]
+   auto cancel_on_conn_lost() -> std::size_t;
+
+   [[nodiscard]]
+   auto get_cancel_run_state() const noexcept -> bool
+   {
+      return cancel_run_called_;
+   }
+
+   [[nodiscard]]
+   auto get_write_buffer() noexcept -> std::string_view
+   {
+      return std::string_view{write_buffer_};
+   }
+
+   void set_receive_adapter(any_adapter adapter);
+
+   [[nodiscard]]
+   auto get_usage() const noexcept -> usage
+   {
+      return usage_;
+   }
+
+   [[nodiscard]]
+   auto is_writing() const noexcept -> bool;
+
+private:
+   [[nodiscard]]
+   auto is_waiting_response() const noexcept -> bool;
+
+   void commit_usage(bool is_push, std::size_t size);
+
+   [[nodiscard]]
+   auto is_next_push(std::string_view data) const noexcept -> bool;
+
+   // Releases the number of requests that have been released.
+   [[nodiscard]]
+   auto release_push_requests() -> std::size_t;
+
+   [[nodiscard]]
+   tribool consume_next_impl(std::string_view data, system::error_code& ec);
+
+   std::string write_buffer_;
+   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 +1,65 @@
+/* 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>;
+
+   // 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);
+   };
+
+   [[nodiscard]]
+   auto prepare_append() -> system::error_code;
+
+   [[nodiscard]]
+   auto get_append_buffer() noexcept -> span_type;
+
+   void commit_append(std::size_t read_size);
+
+   [[nodiscard]]
+   auto get_committed_buffer() const noexcept -> std::string_view;
+
+   [[nodiscard]]
+   auto get_committed_size() const noexcept -> std::size_t;
+
+   void clear();
+
+   // Consume committed data.
+   auto consume_committed(std::size_t size) -> std::size_t;
+
+   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 +1,56 @@
+/* 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/multiplexer.hpp>
+
+#include <boost/asio/cancellation_type.hpp>
+#include <boost/system/error_code.hpp>
+
+#include <cstddef>
+
+namespace boost::redis::detail {
+
+class read_buffer;
+
+class reader_fsm {
+public:
+   struct action {
+      enum class type
+      {
+         setup_cancellation,
+         append_some,
+         needs_more,
+         notify_push_receiver,
+         cancel_run,
+         done,
+      };
+
+      type type_ = type::setup_cancellation;
+      std::size_t push_size_ = 0u;
+      system::error_code ec_ = {};
+   };
+
+   explicit reader_fsm(read_buffer& rbuf, multiplexer& mpx) noexcept;
+
+   action resume(
+      std::size_t bytes_read,
+      system::error_code ec,
+      asio::cancellation_type_t /*cancel_state*/);
+
+private:
+   int resume_point_{0};
+   read_buffer* read_buffer_ = nullptr;
+   action action_after_resume_;
+   action::type next_read_type_ = action::type::append_some;
+   multiplexer* mpx_ = nullptr;
+   std::pair<tribool, std::size_t> res_{std::make_pair(std::nullopt, 0)};
+};
+
+}  // namespace boost::redis::detail
+
+#endif  // BOOST_REDIS_READER_FSM_HPP

include/boost/redis/detail/redis_stream.hpp

@@ -0,0 +1,291 @@
+/* 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/connection_logger.hpp>
+#include <boost/redis/error.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/system/error_code.hpp>
+
+#include <utility>
+
+namespace boost {
+namespace redis {
+namespace detail {
+
+// What transport is redis_stream using?
+enum class transport_type
+{
+   tcp,          // plaintext TCP
+   tcp_tls,      // TLS over TCP
+   unix_socket,  // UNIX domain sockets
+};
+
+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_;
+
+   transport_type transport_{transport_type::tcp};
+   bool ssl_stream_used_{false};
+
+   void reset_stream() { stream_ = {resolv_.get_executor(), ssl_ctx_}; }
+
+   static transport_type transport_from_config(const config& cfg)
+   {
+      if (cfg.unix_socket.empty()) {
+         if (cfg.use_ssl) {
+            return transport_type::tcp_tls;
+         } else {
+            return transport_type::tcp;
+         }
+      } else {
+         BOOST_ASSERT(!cfg.use_ssl);
+         return transport_type::unix_socket;
+      }
+   }
+
+   struct connect_op {
+      redis_stream& obj;
+      const config* cfg;
+      connection_logger* lgr;
+      asio::coroutine coro{};
+
+      // This overload will be used for connects. We only need the endpoint
+      // for logging, so log it and call the coroutine
+      template <class Self>
+      void operator()(
+         Self& self,
+         system::error_code ec,
+         const asio::ip::tcp::endpoint& selected_endpoint)
+      {
+         lgr->on_connect(ec, selected_endpoint);
+         (*this)(self, ec);
+      }
+
+      template <class Self>
+      void operator()(
+         Self& self,
+         system::error_code ec = {},
+         asio::ip::tcp::resolver::results_type resolver_results = {})
+      {
+         BOOST_ASIO_CORO_REENTER(coro)
+         {
+            // Record the transport that we will be using
+            obj.transport_ = transport_from_config(*cfg);
+
+            if (obj.transport_ == transport_type::unix_socket) {
+#ifdef BOOST_ASIO_HAS_LOCAL_SOCKETS
+               // Directly connect to the socket
+               BOOST_ASIO_CORO_YIELD
+               obj.unix_socket_.async_connect(
+                  cfg->unix_socket,
+                  asio::cancel_after(obj.timer_, cfg->connect_timeout, std::move(self)));
+
+               // Log it
+               lgr->on_connect(ec, cfg->unix_socket);
+
+               // If this failed, we can't continue
+               if (ec) {
+                  self.complete(ec == asio::error::operation_aborted ? error::connect_timeout : ec);
+                  return;
+               }
+#else
+               BOOST_ASSERT(false);
+#endif
+            } 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
+               if (cfg->use_ssl && obj.ssl_stream_used_)
+                  obj.reset_stream();
+
+               BOOST_ASIO_CORO_YIELD
+               obj.resolv_.async_resolve(
+                  cfg->addr.host,
+                  cfg->addr.port,
+                  asio::cancel_after(obj.timer_, cfg->resolve_timeout, std::move(self)));
+
+               // Log it
+               lgr->on_resolve(ec, resolver_results);
+
+               // If this failed, we can't continue
+               if (ec) {
+                  self.complete(ec == asio::error::operation_aborted ? error::resolve_timeout : ec);
+                  return;
+               }
+
+               // Connect to the address that the resolver provided us
+               BOOST_ASIO_CORO_YIELD
+               asio::async_connect(
+                  obj.stream_.next_layer(),
+                  std::move(resolver_results),
+                  asio::cancel_after(obj.timer_, cfg->connect_timeout, std::move(self)));
+
+               // Note: logging is performed in the specialized operator() function.
+               // If this failed, we can't continue
+               if (ec) {
+                  self.complete(ec == asio::error::operation_aborted ? error::connect_timeout : ec);
+                  return;
+               }
+
+               if (cfg->use_ssl) {
+                  // Mark the SSL stream as used
+                  obj.ssl_stream_used_ = true;
+
+                  // If we were configured to use TLS, perform the handshake
+                  BOOST_ASIO_CORO_YIELD
+                  obj.stream_.async_handshake(
+                     asio::ssl::stream_base::client,
+                     asio::cancel_after(obj.timer_, cfg->ssl_handshake_timeout, std::move(self)));
+
+                  lgr->on_ssl_handshake(ec);
+
+                  // If this failed, we can't continue
+                  if (ec) {
+                     self.complete(
+                        ec == asio::error::operation_aborted ? error::ssl_handshake_timeout : ec);
+                     return;
+                  }
+               }
+            }
+
+            // Done
+            self.complete(system::error_code());
+         }
+      }
+   };
+
+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 (transport_ == 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 config* cfg, connection_logger* l, CompletionToken&& token)
+   {
+      return asio::async_compose<CompletionToken, void(system::error_code)>(
+         connect_op{*this, cfg, l},
+         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 (transport_) {
+         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 (transport_) {
+         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);
+      }
+   }
+
+   // Cleanup
+   void cancel_resolve() { resolv_.cancel(); }
+
+   void close()
+   {
+      system::error_code ec;
+      if (stream_.next_layer().is_open())
+         stream_.next_layer().close(ec);
+#ifdef BOOST_ASIO_HAS_LOCAL_SOCKETS
+      if (unix_socket_.is_open())
+         unix_socket_.close(ec);
+#endif
+   }
+};
+
+}  // 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_handshaker.hpp

@@ -0,0 +1,115 @@
+/* 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_REDIS_RUNNER_HPP
+#define BOOST_REDIS_RUNNER_HPP
+
+#include <boost/redis/config.hpp>
+#include <boost/redis/detail/connection_logger.hpp>
+#include <boost/redis/error.hpp>
+#include <boost/redis/operation.hpp>
+#include <boost/redis/request.hpp>
+#include <boost/redis/response.hpp>
+
+#include <boost/asio/compose.hpp>
+#include <boost/asio/coroutine.hpp>
+
+#include <string>
+
+namespace boost::redis::detail {
+
+void push_hello(config const& cfg, request& req);
+
+// TODO: Can we avoid this whole function whose only purpose is to
+// check for an error in the hello response and complete with an error
+// so that the parallel group that starts it can exit?
+template <class Handshaker, class ConnectionImpl>
+struct hello_op {
+   Handshaker* handshaker_ = nullptr;
+   ConnectionImpl* conn_ = nullptr;
+   asio::coroutine coro_{};
+
+   template <class Self>
+   void operator()(Self& self, system::error_code ec = {}, std::size_t = 0)
+   {
+      BOOST_ASIO_CORO_REENTER(coro_)
+      {
+         handshaker_->add_hello();
+
+         BOOST_ASIO_CORO_YIELD
+         conn_->async_exec(
+            handshaker_->hello_req_,
+            any_adapter{handshaker_->hello_resp_},
+            std::move(self));
+
+         conn_->logger_.on_hello(ec, handshaker_->hello_resp_);
+
+         if (ec) {
+            conn_->cancel(operation::run);
+            self.complete(ec);
+            return;
+         }
+
+         if (handshaker_->has_error_in_response()) {
+            conn_->cancel(operation::run);
+            self.complete(error::resp3_hello);
+            return;
+         }
+
+         self.complete({});
+      }
+   }
+};
+
+template <class Executor>
+class resp3_handshaker {
+public:
+   void set_config(config const& cfg) { cfg_ = cfg; }
+
+   template <class ConnectionImpl, class CompletionToken>
+   auto async_hello(ConnectionImpl& conn, CompletionToken token)
+   {
+      return asio::async_compose<CompletionToken, void(system::error_code)>(
+         hello_op<resp3_handshaker, ConnectionImpl>{this, &conn},
+         token,
+         conn);
+   }
+
+private:
+   template <class, class> friend struct hello_op;
+
+   void add_hello()
+   {
+      hello_req_.clear();
+      if (hello_resp_.has_value())
+         hello_resp_.value().clear();
+      push_hello(cfg_, hello_req_);
+   }
+
+   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);
+   }
+
+   request hello_req_;
+   generic_response hello_resp_;
+   config cfg_;
+};
+
+}  // namespace boost::redis::detail
+
+#endif  // BOOST_REDIS_RUNNER_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/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/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.
@@ -81,22 +79,34 @@ enum class error
 
    /// Incompatible node depth.
    incompatible_node_depth,
+
+   /// Resp3 hello command error
+   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,
 };
 
-/** \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/connection.ipp

@@ -1,39 +1,56 @@
-/* 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::cancel(operation op) { impl_.cancel(op); }
+
+}  // namespace boost::redis

include/boost/redis/impl/connection_logger.ipp

@@ -0,0 +1,216 @@
+/* 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/detail/connection_logger.hpp>
+#include <boost/redis/logger.hpp>
+
+#include <boost/asio/ip/tcp.hpp>
+#include <boost/system/error_code.hpp>
+
+#include <string>
+
+namespace boost::redis::detail {
+
+#define BOOST_REDIS_READER_SWITCH_CASE(elem) \
+   case reader_fsm::action::type::elem: return "reader_fsm::action::type::" #elem
+
+#define BOOST_REDIS_EXEC_SWITCH_CASE(elem) \
+   case exec_action_type::elem: return "exec_action_type::" #elem
+
+auto to_string(reader_fsm::action::type t) noexcept -> char const*
+{
+   switch (t) {
+      BOOST_REDIS_READER_SWITCH_CASE(setup_cancellation);
+      BOOST_REDIS_READER_SWITCH_CASE(append_some);
+      BOOST_REDIS_READER_SWITCH_CASE(needs_more);
+      BOOST_REDIS_READER_SWITCH_CASE(notify_push_receiver);
+      BOOST_REDIS_READER_SWITCH_CASE(cancel_run);
+      BOOST_REDIS_READER_SWITCH_CASE(done);
+      default: return "action::type::<invalid type>";
+   }
+}
+
+auto to_string(exec_action_type t) noexcept -> char const*
+{
+   switch (t) {
+      BOOST_REDIS_EXEC_SWITCH_CASE(setup_cancellation);
+      BOOST_REDIS_EXEC_SWITCH_CASE(immediate);
+      BOOST_REDIS_EXEC_SWITCH_CASE(done);
+      BOOST_REDIS_EXEC_SWITCH_CASE(notify_writer);
+      BOOST_REDIS_EXEC_SWITCH_CASE(wait_for_response);
+      BOOST_REDIS_EXEC_SWITCH_CASE(cancel_run);
+      default: return "exec_action_type::<invalid type>";
+   }
+}
+
+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());
+}
+
+inline void format_error_code(system::error_code ec, std::string& to)
+{
+   // 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 += ec.message();
+   to += " [";
+   to += ec.to_string();
+   to += ']';
+}
+
+void connection_logger::on_resolve(
+   system::error_code const& ec,
+   asio::ip::tcp::resolver::results_type const& res)
+{
+   if (logger_.lvl < logger::level::info)
+      return;
+
+   if (ec) {
+      msg_ = "Error resolving the server hostname: ";
+      format_error_code(ec, msg_);
+   } else {
+      msg_ = "Resolve results: ";
+      auto iter = res.cbegin();
+      auto end = res.cend();
+
+      if (iter != end) {
+         format_tcp_endpoint(iter->endpoint(), msg_);
+         ++iter;
+         for (; iter != end; ++iter) {
+            msg_ += ", ";
+            format_tcp_endpoint(iter->endpoint(), msg_);
+         }
+      }
+   }
+
+   logger_.fn(logger::level::info, msg_);
+}
+
+void connection_logger::on_connect(system::error_code const& ec, asio::ip::tcp::endpoint const& ep)
+{
+   if (logger_.lvl < logger::level::info)
+      return;
+
+   if (ec) {
+      msg_ = "Failed connecting to the server: ";
+      format_error_code(ec, msg_);
+   } else {
+      msg_ = "Connected to ";
+      format_tcp_endpoint(ep, msg_);
+   }
+
+   logger_.fn(logger::level::info, msg_);
+}
+
+void connection_logger::on_connect(system::error_code const& ec, std::string_view unix_socket_ep)
+{
+   if (logger_.lvl < logger::level::info)
+      return;
+
+   if (ec) {
+      msg_ = "Failed connecting to the server: ";
+      format_error_code(ec, msg_);
+   } else {
+      msg_ = "Connected to ";
+      msg_ += unix_socket_ep;
+   }
+
+   logger_.fn(logger::level::info, msg_);
+}
+
+void connection_logger::on_ssl_handshake(system::error_code const& ec)
+{
+   if (logger_.lvl < logger::level::info)
+      return;
+
+   msg_ = "SSL handshake: ";
+   format_error_code(ec, msg_);
+
+   logger_.fn(logger::level::info, msg_);
+}
+
+void connection_logger::on_write(system::error_code const& ec, std::size_t n)
+{
+   if (logger_.lvl < logger::level::info)
+      return;
+
+   msg_ = "writer_op: ";
+   if (ec) {
+      format_error_code(ec, msg_);
+   } else {
+      msg_ += std::to_string(n);
+      msg_ += " bytes written.";
+   }
+
+   logger_.fn(logger::level::info, msg_);
+}
+
+void connection_logger::on_fsm_resume(reader_fsm::action const& action)
+{
+   if (logger_.lvl < logger::level::debug)
+      return;
+
+   std::string msg;
+   msg += "(";
+   msg += to_string(action.type_);
+   msg += ", ";
+   msg += std::to_string(action.push_size_);
+   msg += ", ";
+   msg += action.ec_.message();
+   msg += ")";
+
+   logger_.fn(logger::level::debug, msg);
+}
+
+void connection_logger::on_hello(system::error_code const& ec, generic_response const& resp)
+{
+   if (logger_.lvl < logger::level::info)
+      return;
+
+   msg_ = "hello_op: ";
+   if (ec) {
+      format_error_code(ec, msg_);
+      if (resp.has_error()) {
+         msg_ += " (";
+         msg_ += resp.error().diagnostic;
+         msg_ += ')';
+      }
+   } else {
+      msg_ += "success";
+   }
+
+   logger_.fn(logger::level::info, msg_);
+}
+
+void connection_logger::log(logger::level lvl, std::string_view message)
+{
+   if (logger_.lvl < lvl)
+      return;
+   logger_.fn(lvl, message);
+}
+
+void connection_logger::log(logger::level lvl, std::string_view op, system::error_code const& ec)
+{
+   if (logger_.lvl < lvl)
+      return;
+
+   msg_ = op;
+   msg_ += ": ";
+   format_error_code(ec, msg_);
+
+   logger_.fn(lvl, msg_);
+}
+
+}  // namespace boost::redis::detail

include/boost/redis/impl/error.ipp

@@ -1,65 +1,74 @@
-/* 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 "RESP3 handshake error (hello command).";
+         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.";
+         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 +1,92 @@
+//
+// 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_EXEC_FSM_IPP
+#define BOOST_REDIS_EXEC_FSM_IPP
+
+#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_cancellation(asio::cancellation_type_t type)
+{
+   return !!(
+      type & (asio::cancellation_type_t::total | asio::cancellation_type_t::partial |
+              asio::cancellation_type_t::terminal));
+}
+
+exec_action exec_fsm::resume(bool connection_is_open, 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
+      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()) {
+            exec_action act{elem_->get_error(), elem_->get_read_size()};
+            elem_.reset();  // Deallocate memory before finalizing
+            return act;
+         }
+
+         // If we're cancelled, try to remove the request from the queue. This will only
+         // succeed if the request is waiting (wasn't written yet)
+         if (is_cancellation(cancel_state) && mpx_->remove(elem_)) {
+            elem_.reset();  // Deallocate memory before finalizing
+            return exec_action{asio::error::operation_aborted};
+         }
+
+         // If we hit a terminal cancellation, tear down the connection.
+         // Otherwise, go back to waiting.
+         // TODO: we could likely do better here and mark the request as cancelled, removing
+         // the done callback and the adapter. But this requires further exploration
+         if (!!(cancel_state & asio::cancellation_type_t::terminal)) {
+            BOOST_REDIS_YIELD(resume_point_, 5, exec_action_type::cancel_run)
+            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/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/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/logger.ipp

@@ -1,203 +1,24 @@
-/* Copyright (c) 2018-2023 Marcelo Zimbres Silva (mzimbres@gmail.com)
- *
- * Distributed under the Boost Software License, Version 1.0. (See
- * accompanying file LICENSE.txt)
- */
+//
+// 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/impl/log_to_file.hpp>
 #include <boost/redis/logger.hpp>
-#include <boost/system/error_code.hpp>
-#include <iostream>
-#include <iterator>
 
-namespace boost::redis
-{
+#include <cstdio>
+#include <string_view>
 
-void logger::write_prefix()
-{
-   if (!std::empty(prefix_))
-      std::clog << prefix_;
-}
+namespace boost::redis {
 
-void logger::on_resolve(system::error_code const& ec, asio::ip::tcp::resolver::results_type const& res)
-{
-   if (level_ < level::info)
-      return;
+logger::logger(level l)
+: lvl{l}
+, fn{[](level, std::string_view msg) {
+   detail::log_to_file(stderr, msg);
+}}
+{ }
 
-   write_prefix();
-
-   std::clog << "run-all-op: resolve addresses ";
-
-   if (ec) {
-      std::clog << ec.message() << std::endl;
-   } else {
-      auto begin = std::cbegin(res);
-      auto end = std::cend(res);
-
-      if (begin == end)
-         return;
-
-      std::clog << begin->endpoint();
-      for (auto iter = std::next(begin); iter != end; ++iter)
-         std::clog << ", " << iter->endpoint();
-   }
-
-   std::clog << std::endl;
-}
-
-void logger::on_connect(system::error_code const& ec, asio::ip::tcp::endpoint const& ep)
-{
-   if (level_ < level::info)
-      return;
-
-   write_prefix();
-
-   std::clog << "run-all-op: connected to endpoint ";
-
-   if (ec)
-      std::clog << ec.message() << std::endl;
-   else
-      std::clog << ep;
-
-   std::clog << std::endl;
-}
-
-void logger::on_ssl_handshake(system::error_code const& ec)
-{
-   if (level_ < level::info)
-      return;
-
-   write_prefix();
-
-   std::clog << "Runner: SSL handshake " << ec.message() << std::endl;
-}
-
-void logger::on_connection_lost(system::error_code const& ec)
-{
-   if (level_ < level::info)
-      return;
-
-   write_prefix();
-
-   if (ec)
-      std::clog << "Connection lost: " << ec.message();
-   else
-      std::clog << "Connection lost.";
-
-   std::clog << std::endl;
-}
-
-void
-logger::on_write(
-   system::error_code const& ec,
-   std::string const& payload)
-{
-   if (level_ < level::info)
-      return;
-
-   write_prefix();
-
-   if (ec)
-      std::clog << "writer-op: " << ec.message();
-   else
-      std::clog << "writer-op: " << std::size(payload) << " bytes written.";
-
-   std::clog << std::endl;
-}
-
-void logger::on_read(system::error_code const& ec, std::size_t n)
-{
-   if (level_ < level::info)
-      return;
-
-   write_prefix();
-
-   if (ec)
-      std::clog << "reader-op: " << ec.message();
-   else
-      std::clog << "reader-op: " << n << " bytes read.";
-
-   std::clog << std::endl;
-}
-
-void logger::on_run(system::error_code const& reader_ec, system::error_code const& writer_ec)
-{
-   if (level_ < level::info)
-      return;
-
-   write_prefix();
-
-   std::clog << "run-op: "
-      << reader_ec.message() << " (reader), "
-      << writer_ec.message() << " (writer)";
-
-   std::clog << std::endl;
-}
-
-void
-logger::on_hello(
-   system::error_code const& ec,
-   generic_response const& resp)
-{
-   if (level_ < level::info)
-      return;
-
-   write_prefix();
-
-   if (ec) {
-      std::clog << "hello-op: " << ec.message();
-      if (resp.has_error())
-         std::clog << " (" << resp.error().diagnostic << ")";
-   } else {
-      std::clog << "hello-op: Success";
-   }
-
-   std::clog << std::endl;
-}
-
-void
-   logger::on_runner(
-      system::error_code const& run_all_ec,
-      system::error_code const& health_check_ec,
-      system::error_code const& hello_ec)
-{
-   if (level_ < level::info)
-      return;
-
-   write_prefix();
-
-   std::clog << "runner-op: "
-      << run_all_ec.message() << " (async_run_all), "
-      << health_check_ec.message() << " (async_health_check) " 
-      << hello_ec.message() << " (async_hello).";
-
-   std::clog << std::endl;
-}
-
-void
-   logger::on_check_health(
-      system::error_code const& ping_ec,
-      system::error_code const& timeout_ec)
-{
-   if (level_ < level::info)
-      return;
-
-   write_prefix();
-
-   std::clog << "check-health-op: "
-      << ping_ec.message() << " (async_ping), "
-      << timeout_ec.message() << " (async_check_timeout).";
-
-   std::clog << std::endl;
-}
-
-void logger::trace(std::string_view reason)
-{
-   if (level_ < level::debug)
-      return;
-
-   write_prefix();
-
-   std::clog << reason << std::endl;
-}
-
-} // boost::redis
+}  // namespace boost::redis

include/boost/redis/impl/multiplexer.ipp

@@ -0,0 +1,322 @@
+/* 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/detail/multiplexer.hpp>
+#include <boost/redis/request.hpp>
+
+#include <memory>
+
+namespace boost::redis::detail {
+
+multiplexer::elem::elem(request const& req, any_adapter adapter)
+: req_{&req}
+, adapter_{std::move(adapter)}
+, remaining_responses_{req.get_expected_responses()}
+, status_{status::waiting}
+, ec_{}
+, read_size_{0}
+{ }
+
+auto multiplexer::elem::notify_error(system::error_code ec) noexcept -> void
+{
+   if (!ec_) {
+      ec_ = ec;
+   }
+
+   notify_done();
+}
+
+auto multiplexer::elem::commit_response(std::size_t read_size) -> void
+{
+   read_size_ += read_size;
+   --remaining_responses_;
+}
+
+bool multiplexer::remove(std::shared_ptr<elem> const& ptr)
+{
+   if (ptr->is_waiting()) {
+      reqs_.erase(std::remove(std::begin(reqs_), std::end(reqs_), ptr));
+      return true;
+   }
+
+   return false;
+}
+
+std::size_t multiplexer::commit_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();
+
+   // 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();
+      }
+   });
+
+   return release_push_requests();
+}
+
+void multiplexer::add(std::shared_ptr<elem> const& info)
+{
+   reqs_.push_back(info);
+
+   if (info->get_request().has_hello_priority()) {
+      auto rend = std::partition_point(std::rbegin(reqs_), std::rend(reqs_), [](auto const& e) {
+         return e->is_waiting();
+      });
+
+      std::rotate(std::rbegin(reqs_), std::rbegin(reqs_) + 1, rend);
+   }
+}
+
+tribool multiplexer::consume_next_impl(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.
+   //
+
+   BOOST_ASSERT(!data.empty());
+   if (!on_push_)  // Prepare for new message.
+      on_push_ = is_next_push(data);
+
+   if (on_push_) {
+      if (!resp3::parse(parser_, data, receive_adapter_, ec))
+         return std::nullopt;
+
+      return std::make_optional(true);
+   }
+
+   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()->get_remaining_responses() != 0);
+
+   if (!resp3::parse(parser_, data, reqs_.front()->get_adapter(), ec))
+      return std::nullopt;
+
+   if (ec) {
+      reqs_.front()->notify_error(ec);
+      reqs_.pop_front();
+      return std::make_optional(false);
+   }
+
+   reqs_.front()->commit_response(parser_.get_consumed());
+   if (reqs_.front()->get_remaining_responses() == 0) {
+      // Done with this request.
+      reqs_.front()->notify_done();
+      reqs_.pop_front();
+   }
+
+   return std::make_optional(false);
+}
+
+std::pair<tribool, std::size_t> multiplexer::consume_next(
+   std::string_view data,
+   system::error_code& ec)
+{
+   auto const ret = consume_next_impl(data, ec);
+   auto const consumed = parser_.get_consumed();
+   if (ec) {
+      return std::make_pair(ret, consumed);
+   }
+
+   if (ret.has_value()) {
+      parser_.reset();
+      commit_usage(ret.value(), consumed);
+      return std::make_pair(ret, consumed);
+   }
+
+   return std::make_pair(std::nullopt, consumed);
+}
+
+void multiplexer::reset()
+{
+   write_buffer_.clear();
+   parser_.reset();
+   on_push_ = false;
+   cancel_run_called_ = false;
+}
+
+std::size_t multiplexer::prepare_write()
+{
+   // 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();
+      });
+
+   std::for_each(point, std::cend(reqs_), [this](auto const& ri) {
+      // Stage the request.
+      write_buffer_ += ri->get_request().payload();
+      ri->mark_staged();
+      usage_.commands_sent += ri->get_request().get_commands();
+   });
+
+   usage_.bytes_sent += std::size(write_buffer_);
+
+   auto const d = std::distance(point, std::cend(reqs_));
+   return static_cast<std::size_t>(d);
+}
+
+std::size_t multiplexer::cancel_waiting()
+{
+   auto f = [](auto const& ptr) {
+      BOOST_ASSERT(ptr != nullptr);
+      return !ptr->is_waiting();
+   };
+
+   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->notify_error({asio::error::operation_aborted});
+   });
+
+   reqs_.erase(point, std::end(reqs_));
+   return ret;
+}
+
+auto multiplexer::cancel_on_conn_lost() -> std::size_t
+{
+   // Protects the code below from being called more than
+   // once, see https://github.com/boostorg/redis/issues/181
+   if (std::exchange(cancel_run_called_, true)) {
+      return 0;
+   }
+
+   // Must return false if the request should be removed.
+   auto cond = [](auto const& ptr) {
+      BOOST_ASSERT(ptr != nullptr);
+
+      if (ptr->is_waiting()) {
+         return !ptr->get_request().get_config().cancel_on_connection_lost;
+      } else {
+         return !ptr->get_request().get_config().cancel_if_unresponded;
+      }
+   };
+
+   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->notify_error({asio::error::operation_aborted});
+   });
+
+   reqs_.erase(point, std::end(reqs_));
+
+   std::for_each(std::begin(reqs_), std::end(reqs_), [](auto const& ptr) {
+      return ptr->mark_waiting();
+   });
+
+   return ret;
+}
+
+void multiplexer::commit_usage(bool is_push, std::size_t size)
+{
+   if (is_push) {
+      usage_.pushes_received += 1;
+      usage_.push_bytes_received += size;
+      on_push_ = false;
+   } else {
+      usage_.responses_received += 1;
+      usage_.response_bytes_received += size;
+   }
+}
+
+bool multiplexer::is_next_push(std::string_view data) const noexcept
+{
+   // Useful links to understand the heuristics below.
+   //
+   // - https://github.com/redis/redis/issues/11784
+   // - https://github.com/redis/redis/issues/6426
+   // - https://github.com/boostorg/redis/issues/170
+
+   // Test if the message resp3 type is a push.
+   BOOST_ASSERT(!data.empty());
+   if (resp3::to_type(data.front()) == resp3::type::push)
+      return true;
+
+   // This is non-push type and the requests queue is empty. I have
+   // noticed this is possible, for example with -MISCONF. I don't
+   // know why they are not sent with a push type so we can
+   // distinguish them from responses to commands. If we are lucky
+   // enough to receive them when the command queue is empty they
+   // can be treated as server pushes, otherwise it is impossible
+   // to handle them properly
+   if (reqs_.empty())
+      return true;
+
+   // The request does not expect any response but we got one. This
+   // may happen if for example, subscribe with wrong syntax.
+   if (reqs_.front()->get_remaining_responses() == 0)
+      return true;
+
+   // Added to deal with MONITOR and also to fix PR170 which
+   // happens under load and on low-latency networks, where we
+   // might start receiving responses before the write operation
+   // completed and the request is still maked as staged and not
+   // written.
+   return reqs_.front()->is_waiting();
+}
+
+std::size_t multiplexer::release_push_requests()
+{
+   auto point = std::stable_partition(std::begin(reqs_), std::end(reqs_), [](auto const& ptr) {
+      return !(ptr->is_written() && ptr->get_request().get_expected_responses() == 0);
+   });
+
+   std::for_each(point, std::end(reqs_), [](auto const& ptr) {
+      ptr->notify_done();
+   });
+
+   auto const d = std::distance(point, std::end(reqs_));
+   reqs_.erase(point, std::end(reqs_));
+   return static_cast<std::size_t>(d);
+}
+
+bool multiplexer::is_waiting_response() const noexcept
+{
+   if (std::empty(reqs_))
+      return false;
+
+   // Under load and on low-latency networks we might start
+   // receiving responses before the write operation completed and
+   // the request is still maked as staged and not written.  See
+   // https://github.com/boostorg/redis/issues/170
+   return !reqs_.front()->is_waiting();
+}
+
+bool multiplexer::is_writing() const noexcept { return !write_buffer_.empty(); }
+
+void multiplexer::set_receive_adapter(any_adapter adapter)
+{
+   receive_adapter_ = std::move(adapter);
+}
+
+auto make_elem(request const& req, any_adapter adapter) -> std::shared_ptr<multiplexer::elem>
+{
+   return std::make_shared<multiplexer::elem>(req, std::move(adapter));
+}
+
+}  // namespace boost::redis::detail

include/boost/redis/impl/read_buffer.ipp

@@ -0,0 +1,79 @@
+/* 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/detail/read_buffer.hpp>
+
+#include <boost/assert.hpp>
+#include <boost/core/make_span.hpp>
+
+#include <utility>
+
+namespace boost::redis::detail {
+
+system::error_code read_buffer::prepare_append()
+{
+   BOOST_ASSERT(append_buf_begin_ == buffer_.size());
+
+   auto const new_size = append_buf_begin_ + cfg_.read_buffer_append_size;
+
+   if (new_size > cfg_.max_read_size) {
+      return error::exceeds_maximum_read_buffer_size;
+   }
+
+   buffer_.resize(new_size);
+   return {};
+}
+
+void read_buffer::commit_append(std::size_t read_size)
+{
+   BOOST_ASSERT(buffer_.size() >= (append_buf_begin_ + read_size));
+   buffer_.resize(append_buf_begin_ + read_size);
+   append_buf_begin_ = buffer_.size();
+}
+
+auto read_buffer::get_append_buffer() noexcept -> span_type
+{
+   auto const size = buffer_.size();
+   return make_span(buffer_.data() + append_buf_begin_, size - append_buf_begin_);
+}
+
+auto read_buffer::get_committed_buffer() const noexcept -> std::string_view
+{
+   BOOST_ASSERT(!buffer_.empty());
+   return {buffer_.data(), append_buf_begin_};
+}
+
+auto read_buffer::get_committed_size() const noexcept -> std::size_t { return append_buf_begin_; }
+
+void read_buffer::clear()
+{
+   buffer_.clear();
+   append_buf_begin_ = 0;
+}
+
+std::size_t read_buffer::consume_committed(std::size_t size)
+{
+   // For convenience, if the requested size is larger than the
+   // committed buffer we cap it to the maximum.
+   if (size > append_buf_begin_)
+      size = append_buf_begin_;
+
+   buffer_.erase(buffer_.begin(), buffer_.begin() + size);
+   BOOST_ASSERT(append_buf_begin_ >= size);
+   append_buf_begin_ -= size;
+   return size;
+}
+
+void read_buffer::reserve(std::size_t n) { buffer_.reserve(n); }
+
+bool operator==(read_buffer const& lhs, read_buffer const& rhs)
+{
+   return lhs.buffer_ == rhs.buffer_ && lhs.append_buf_begin_ == rhs.append_buf_begin_;
+}
+
+bool operator!=(read_buffer const& lhs, read_buffer const& rhs) { return !(lhs == rhs); }
+
+}  // namespace boost::redis::detail

include/boost/redis/impl/reader_fsm.ipp

@@ -0,0 +1,88 @@
+/* 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/detail/coroutine.hpp>
+#include <boost/redis/detail/multiplexer.hpp>
+#include <boost/redis/detail/read_buffer.hpp>
+#include <boost/redis/detail/reader_fsm.hpp>
+
+namespace boost::redis::detail {
+
+reader_fsm::reader_fsm(read_buffer& rbuf, multiplexer& mpx) noexcept
+: read_buffer_{&rbuf}
+, mpx_{&mpx}
+{ }
+
+reader_fsm::action reader_fsm::resume(
+   std::size_t bytes_read,
+   system::error_code ec,
+   asio::cancellation_type_t /*cancel_state*/)
+{
+   switch (resume_point_) {
+      BOOST_REDIS_CORO_INITIAL
+      BOOST_REDIS_YIELD(resume_point_, 1, action::type::setup_cancellation)
+
+      for (;;) {
+         ec = read_buffer_->prepare_append();
+         if (ec) {
+            action_after_resume_ = {action::type::done, 0, ec};
+            BOOST_REDIS_YIELD(resume_point_, 2, action::type::cancel_run)
+            return action_after_resume_;
+         }
+
+         BOOST_REDIS_YIELD(resume_point_, 3, next_read_type_)
+         read_buffer_->commit_append(bytes_read);
+         if (ec) {
+            // TODO: If an error occurred but data was read (i.e.
+            // bytes_read != 0) we should try to process that data and
+            // deliver it to the user before calling cancel_run.
+            action_after_resume_ = {action::type::done, bytes_read, ec};
+            BOOST_REDIS_YIELD(resume_point_, 4, action::type::cancel_run)
+            return action_after_resume_;
+         }
+
+         next_read_type_ = action::type::append_some;
+         while (read_buffer_->get_committed_size() != 0) {
+            res_ = mpx_->consume_next(read_buffer_->get_committed_buffer(), ec);
+            if (ec) {
+               // TODO: Perhaps log what has not been consumed to aid
+               // debugging.
+               action_after_resume_ = {action::type::done, res_.second, ec};
+               BOOST_REDIS_YIELD(resume_point_, 5, action::type::cancel_run)
+               return action_after_resume_;
+            }
+
+            if (!res_.first.has_value()) {
+               next_read_type_ = action::type::needs_more;
+               break;
+            }
+
+            read_buffer_->consume_committed(res_.second);
+
+            if (res_.first.value()) {
+               BOOST_REDIS_YIELD(resume_point_, 6, action::type::notify_push_receiver, res_.second)
+               if (ec) {
+                  action_after_resume_ = {action::type::done, 0u, ec};
+                  BOOST_REDIS_YIELD(resume_point_, 7, action::type::cancel_run)
+                  return action_after_resume_;
+               }
+            } else {
+               // TODO: Here we should notify the exec operation that
+               // it can be completed. This will improve log clarity
+               // and will make this code symmetrical in how it
+               // handles pushes and other messages. The new action
+               // type can be named notify_exec. To do that we need to
+               // refactor the multiplexer.
+            }
+         }
+      }
+   }
+
+   BOOST_ASSERT(false);
+   return {action::type::done, 0, system::error_code()};
+}
+
+}  // namespace boost::redis::detail

include/boost/redis/impl/request.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)
@@ -12,10 +12,13 @@ namespace boost::redis::detail {
 
 auto has_response(std::string_view cmd) -> bool
 {
-   if (cmd == "SUBSCRIBE") return true;
-   if (cmd == "PSUBSCRIBE") return true;
-   if (cmd == "UNSUBSCRIBE") return true;
+   if (cmd == "SUBSCRIBE")
+      return true;
+   if (cmd == "PSUBSCRIBE")
+      return true;
+   if (cmd == "UNSUBSCRIBE")
+      return true;
    return false;
 }
 
-} // boost:redis::detail
+}  // namespace boost::redis::detail

include/boost/redis/impl/resp3_handshaker.ipp

@@ -0,0 +1,26 @@
+/* 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/detail/resp3_handshaker.hpp>
+
+namespace boost::redis::detail {
+
+void push_hello(config const& cfg, request& req)
+{
+   if (!cfg.username.empty() && !cfg.password.empty() && !cfg.clientname.empty())
+      req.push("HELLO", "3", "AUTH", cfg.username, cfg.password, "SETNAME", cfg.clientname);
+   else if (cfg.password.empty() && cfg.clientname.empty())
+      req.push("HELLO", "3");
+   else if (cfg.clientname.empty())
+      req.push("HELLO", "3", "AUTH", cfg.username, cfg.password);
+   else
+      req.push("HELLO", "3", "SETNAME", cfg.clientname);
+
+   if (cfg.database_index && cfg.database_index.value() != 0)
+      req.push("SELECT", cfg.database_index.value());
+}
+
+}  // namespace boost::redis::detail

include/boost/redis/impl/response.ipp

@@ -1,23 +1,23 @@
-/* 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/response.hpp>
 #include <boost/redis/error.hpp>
+#include <boost/redis/response.hpp>
+
 #include <boost/assert.hpp>
 
-namespace boost::redis
-{
+namespace boost::redis {
 
 void consume_one(generic_response& r, system::error_code& ec)
 {
    if (r.has_error())
-      return; // Nothing to consume.
+      return;  // Nothing to consume.
 
    if (std::empty(r.value()))
-      return; // Nothing to consume.
+      return;  // Nothing to consume.
 
    auto const depth = r.value().front().depth;
 
@@ -29,8 +29,9 @@ void consume_one(generic_response& r, system::error_code& ec)
       return;
    }
 
-   auto f = [depth](auto const& e)
-      { return e.depth == depth; };
+   auto f = [depth](auto const& e) {
+      return e.depth == depth;
+   };
 
    auto match = std::find_if(std::next(std::cbegin(r.value())), std::cend(r.value()), f);
 
@@ -45,4 +46,4 @@ void consume_one(generic_response& r)
       throw system::system_error(ec);
 }
 
-} // boost::redis::resp3
+}  // namespace boost::redis

include/boost/redis/logger.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)
@@ -7,28 +7,17 @@
 #ifndef BOOST_REDIS_LOGGER_HPP
 #define BOOST_REDIS_LOGGER_HPP
 
-#include <boost/redis/response.hpp>
-#include <boost/asio/ip/tcp.hpp>
-#include <string>
-
-namespace boost::system {class error_code;}
+#include <functional>
+#include <string_view>
 
 namespace boost::redis {
 
-/** @brief Logger class
- *  @ingroup high-level-api
+/** @brief Defines logging configuration.
  *
- *  The class can be passed to the connection objects to log to `std::clog`
- *
- *  Notice that currently this class has no stable interface. Users
- *  that don't want any logging can disable it by contructing a logger
- *  with logger::level::emerg to the connection.
+ *  See the member descriptions for more info.
  */
-class logger {
-public:
-   /** @brief Syslog-like log levels
-    *  @ingroup high-level-api
-    */
+struct logger {
+   /// Syslog-like log levels.
    enum class level
    {
       /// Disabled
@@ -56,116 +45,53 @@ public:
       info,
 
       /// Debug
-      debug
+      debug,
    };
 
-   /** @brief Constructor
-    *  @ingroup high-level-api
+   /** @brief Constructor from a level.
     *
-    *  @param l Log level.
-    */
-   logger(level l = level::disabled)
-   : level_{l}
-   {}
-
-   /** @brief Called when the resolve operation completes.
-    *  @ingroup high-level-api
+    * Constructs a logger with the specified level
+    * and a logging function that prints messages to `stderr`.
     *
-    *  @param ec Error returned by the resolve operation.
-    *  @param res Resolve results.
-    */
-   void on_resolve(system::error_code const& ec, asio::ip::tcp::resolver::results_type const& res);
-
-   /** @brief Called when the connect operation completes.
-    *  @ingroup high-level-api
+    * @param l The value to set @ref lvl to.
     *
-    *  @param ec Error returned by the connect operation.
-    *  @param ep Endpoint to which the connection connected.
+    * @par Exceptions
+    * No-throw guarantee.
     */
-   void on_connect(system::error_code const& ec, asio::ip::tcp::endpoint const& ep);
+   logger(level l = level::info);
 
-   /** @brief Called when the ssl handshake operation completes.
-    *  @ingroup high-level-api
+   /** @brief Constructor from a level and a function.
     *
-    *  @param ec Error returned by the handshake operation.
-    */
-   void on_ssl_handshake(system::error_code const& ec);
-
-   /** @brief Called when the connection is lost.
-    *  @ingroup high-level-api
+    * Constructs a logger by setting its members to the specified values.
     *
-    *  @param ec Error returned when the connection is lost.
-    */
-   void on_connection_lost(system::error_code const& ec);
-
-   /** @brief Called when the write operation completes.
-    *  @ingroup high-level-api
+    * @param l The value to set @ref lvl to.
+    * @param fn The value to set @ref fn to.
     *
-    *  @param ec Error code returned by the write operation.
-    *  @param payload The payload written to the socket.
+    * @par Exceptions
+    * No-throw guarantee.
     */
-   void on_write(system::error_code const& ec, std::string const& payload);
+   logger(level l, std::function<void(level, std::string_view)> fn)
+   : lvl{l}
+   , fn{std::move(fn)}
+   { }
 
-   /** @brief Called when the read operation completes.
-    *  @ingroup high-level-api
+   /**
+    * @brief Defines a severity filter for messages.
     *
-    *  @param ec Error code returned by the read operation.
-    *  @param n Number of bytes read.
+    * Only messages with a level >= to the one specified by the logger
+    * will be logged.
     */
-   void on_read(system::error_code const& ec, std::size_t n);
+   level lvl;
 
-   /** @brief Called when the run operation completes.
-    *  @ingroup high-level-api
+   /**
+    * @brief Defines a severity filter for messages.
     *
-    *  @param reader_ec Error code returned by the read operation.
-    *  @param writer_ec Error code returned by the write operation.
+    * Only messages with a level >= to the one specified by the logger
+    * will be logged.
     */
-   void on_run(system::error_code const& reader_ec, system::error_code const& writer_ec);
-
-   /** @brief Called when the `HELLO` request completes.
-    *  @ingroup high-level-api
-    *
-    *  @param ec Error code returned by the async_exec operation.
-    *  @param resp Response sent by the Redis server.
-    */
-   void on_hello(system::error_code const& ec, generic_response const& resp);
-
-   /** @brief Sets a prefix to every log message
-    *  @ingroup high-level-api
-    *
-    *  @param prefix The prefix.
-    */
-   void set_prefix(std::string_view prefix)
-   {
-      prefix_ = prefix;
-   }
-
-   /** @brief Called when the runner operation completes.
-    *  @ingroup high-level-api
-    *
-    *  @param run_all_ec Error code returned by the run_all operation.
-    *  @param health_check_ec Error code returned by the health checker operation.
-    *  @param hello_ec Error code returned by the health checker operation.
-    */
-   void
-      on_runner(
-         system::error_code const& run_all_ec,
-         system::error_code const& health_check_ec,
-         system::error_code const& hello_ec);
-
-   void
-      on_check_health(
-         system::error_code const& ping_ec,
-         system::error_code const& check_timeout_ec);
-
-   void trace(std::string_view reason);
-
-private:
-   void write_prefix();
-   level level_;
-   std::string_view prefix_;
+   std::function<void(level, std::string_view)> fn;
 };
 
-} // boost::redis
+}  // namespace boost::redis
 
-#endif // BOOST_REDIS_LOGGER_HPP
+#endif  // BOOST_REDIS_LOGGER_HPP

include/boost/redis/operation.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)
@@ -10,12 +10,12 @@
 namespace boost::redis {
 
 /** @brief Connection operations that can be cancelled.
- *  @ingroup high-level-api
  *  
  *  The operations listed below can be passed to the
- *  `boost::redis::connection::cancel` member function.
+ *  @ref boost::redis::connection::cancel member function.
  */
-enum class operation {
+enum class operation
+{
    /// Resolve operation.
    resolve,
    /// Connect operation.
@@ -36,6 +36,6 @@ enum class operation {
    all,
 };
 
-} // boost::redis
+}  // namespace boost::redis
 
-#endif // BOOST_REDIS_OPERATION_HPP
+#endif  // BOOST_REDIS_OPERATION_HPP

include/boost/redis/request.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)
@@ -7,28 +7,29 @@
 #ifndef BOOST_REDIS_REQUEST_HPP
 #define BOOST_REDIS_REQUEST_HPP
 
-#include <boost/redis/resp3/type.hpp>
 #include <boost/redis/resp3/serialization.hpp>
+#include <boost/redis/resp3/type.hpp>
 
+#include <algorithm>
 #include <string>
 #include <tuple>
-#include <algorithm>
 
 // NOTE: For some commands like hset it would be a good idea to assert
 // the value type is a pair.
 
 namespace boost::redis {
 
-namespace detail{
+namespace detail {
 auto has_response(std::string_view cmd) -> bool;
 }
 
-/** \brief Creates Redis requests.
- *  \ingroup high-level-api
+/** @brief Represents a Redis request.
  *  
  *  A request is composed of one or more Redis commands and is
- *  referred to in the redis documentation as a pipeline, see
- *  https://redis.io/topics/pipelining. For example
+ *  referred to in the redis documentation as a pipeline. See
+ *  <a href="https://redis.io/topics/pipelining"></a> for more info.
+ *
+ *  For example:
  *
  *  @code
  *  request r;
@@ -39,64 +40,64 @@ auto has_response(std::string_view cmd) -> bool;
  *  r.push("QUIT");
  *  @endcode
  *
- *  \remarks
- *
- *  Uses a std::string for internal storage.
+ *  Uses a `std::string` for internal storage.
  */
 class request {
 public:
    /// Request configuration options.
    struct config {
-      /** \brief If `true` 
-       * `boost::redis::connection::async_exec` will complete with error if the
-       * connection is lost. Affects only requests that haven't been
-       * sent yet.
+      /** @brief If `true`, calls to @ref basic_connection::async_exec will
+       * complete with error if the connection is lost while the
+       * request hasn't been sent yet.
        */
       bool cancel_on_connection_lost = true;
 
-      /** \brief If `true` the request will complete with
-       * boost::redis::error::not_connected if `async_exec` is called before
-       * the connection with Redis was established.
+      /** @brief If `true`, @ref basic_connection::async_exec will complete with
+       * @ref boost::redis::error::not_connected if the call happens
+       * before the connection with Redis was established.
        */
       bool cancel_if_not_connected = false;
 
-      /** \brief If `false` `boost::redis::connection::async_exec` will not
+      /** @brief If `false`, @ref basic_connection::async_exec will not
        * automatically cancel this request if the connection is lost.
        * Affects only requests that have been written to the socket
-       * but remained unresponded when `boost::redis::connection::async_run`
-       * completed.
+       * but have not been responded when
+       * @ref boost::redis::connection::async_run completes.
        */
       bool cancel_if_unresponded = true;
 
-      /** \brief If this request has a `HELLO` command and this flag is
-       * `true`, the `boost::redis::connection` will move it to the front of
-       * the queue of awaiting requests. This makes it possible to
-       * send `HELLO` and authenticate before other commands are sent.
+      /** @brief If this request has a `HELLO` command and this flag
+       * is `true`, it will be moved to the
+       * front of the queue of awaiting requests. This makes it
+       * possible to send `HELLO` commands and authenticate before other
+       * commands are sent.
        */
       bool hello_with_priority = true;
    };
 
-   /** \brief Constructor
+   /** @brief Constructor
     *  
-    *  \param cfg Configuration options.
+    *  @param cfg Configuration options.
     */
-    explicit
-    request(config cfg = config{true, false, true, true})
-    : cfg_{cfg} {}
+   explicit request(config cfg = config{true, false, true, true})
+   : cfg_{cfg}
+   { }
 
-    //// Returns the number of responses expected for this request.
+   /// Returns the number of responses expected for this request.
    [[nodiscard]] auto get_expected_responses() const noexcept -> std::size_t
-      { return expected_responses_;};
+   {
+      return expected_responses_;
+   };
 
-    //// Returns the number of commands contained in this request.
-   [[nodiscard]] auto get_commands() const noexcept -> std::size_t
-      { return commands_;};
+   /// Returns the number of commands contained in this request.
+   [[nodiscard]] auto get_commands() const noexcept -> std::size_t { return commands_; };
 
-   [[nodiscard]] auto payload() const noexcept -> std::string_view
-      { return payload_;}
+   [[nodiscard]] auto payload() const noexcept -> std::string_view { return payload_; }
 
    [[nodiscard]] auto has_hello_priority() const noexcept -> auto const&
-      { return has_hello_priority_;}
+   {
+      return has_hello_priority_;
+   }
 
    /// Clears the request preserving allocated memory.
    void clear()
@@ -107,40 +108,43 @@ public:
       has_hello_priority_ = false;
    }
 
-   /// Calls std::string::reserve on the internal storage.
-   void reserve(std::size_t new_cap = 0)
-      { payload_.reserve(new_cap); }
-
-   /// Returns a const reference to the config object.
-   [[nodiscard]] auto get_config() const noexcept -> auto const& {return cfg_; }
+   /// Calls `std::string::reserve` on the internal storage.
+   void reserve(std::size_t new_cap = 0) { payload_.reserve(new_cap); }
 
    /// Returns a reference to the config object.
-   [[nodiscard]] auto get_config() noexcept -> auto& {return cfg_; }
+   [[nodiscard]] auto get_config() const noexcept -> config const& { return cfg_; }
+
+   /// Returns a reference to the config object.
+   [[nodiscard]] auto get_config() noexcept -> config& { return cfg_; }
 
    /** @brief Appends a new command to the end of the request.
     *
-    *  For example
+    *  For example:
     *
-    *  \code
+    *  @code
     *  request req;
     *  req.push("SET", "key", "some string", "EX", "2");
-    *  \endcode
+    *  @endcode
     *
-    *  will add the `set` command with value "some string" and an
+    *  This will add a `SET` command with value `"some string"` and an
     *  expiration of 2 seconds.
     *
-    *  \param cmd The command e.g redis or sentinel command.
-    *  \param args Command arguments.
-    *  \tparam Ts Non-string types will be converted to string by calling `boost_redis_to_bulk` on each argument. This function must be made available over ADL and must have the following signature
+    *  Command arguments should either be convertible to `std::string_view`
+    *  or support the `boost_redis_to_bulk` function.
+    *  This function is a customization point that must be made available
+    *  using ADL and must have the following signature:
     *
     *  @code
     *  void boost_redis_to_bulk(std::string& to, T const& t);
-    *  {
-    *     boost::redis::resp3::boost_redis_to_bulk(to, serialize(t));
-    *  }
     *  @endcode
     *
+    *
     *  See cpp20_serialization.cpp
+    *
+    *  @param cmd The command to execute. It should be a redis or sentinel command, like `"SET"`.
+    *  @param args Command arguments. Non-string types will be converted to string by calling `boost_redis_to_bulk` on each argument.
+    *  @tparam Ts Types of the command arguments.
+    *
     */
    template <class... Ts>
    void push(std::string_view cmd, Ts const&... args)
@@ -156,7 +160,7 @@ public:
    /** @brief Appends a new command to the end of the request.
     *  
     *  This overload is useful for commands that have a key and have a
-    *  dynamic range of arguments. For example
+    *  dynamic range of arguments. For example:
     *
     *  @code
     *  std::map<std::string, std::string> map
@@ -166,32 +170,34 @@ public:
     *     };
     *
     *  request req;
-    *  req.push_range("HSET", "key", std::cbegin(map), std::cend(map));
+    *  req.push_range("HSET", "key", map.cbegin(), map.cend());
     *  @endcode
-    *  
-    *  \param cmd The command e.g. Redis or Sentinel command.
-    *  \param key The command key.
-    *  \param begin Iterator to the begin of the range.
-    *  \param end Iterator to the end of the range.
-    *  \tparam Ts Non-string types will be converted to string by calling `boost_redis_to_bulk` on each argument. This function must be made available over ADL and must have the following signature
+    *
+    *  Command arguments should either be convertible to `std::string_view`
+    *  or support the `boost_redis_to_bulk` function.
+    *  This function is a customization point that must be made available
+    *  using ADL and must have the following signature:
     *
     *  @code
     *  void boost_redis_to_bulk(std::string& to, T const& t);
-    *  {
-    *     boost::redis::resp3::boost_redis_to_bulk(to, serialize(t));
-    *  }
     *  @endcode
+    *  
+    *  @param cmd The command to execute. It should be a redis or sentinel command, like `"SET"`.
+    *  @param key The command key. It will be added as the first argument to the command.
+    *  @param begin Iterator to the begin of the range.
+    *  @param end Iterator to the end of the range.
+    *  @tparam ForwardIterator A forward iterator with an element type that is convertible to `std::string_view`
+    *          or supports `boost_redis_to_bulk`.
     *
     *  See cpp20_serialization.cpp
     */
    template <class ForwardIterator>
-   void
-   push_range(
-      std::string_view const& cmd,
-      std::string_view const& key,
+   void push_range(
+      std::string_view cmd,
+      std::string_view key,
       ForwardIterator begin,
       ForwardIterator end,
-      typename std::iterator_traits<ForwardIterator>::value_type * = nullptr)
+      typename std::iterator_traits<ForwardIterator>::value_type* = nullptr)
    {
       using value_type = typename std::iterator_traits<ForwardIterator>::value_type;
 
@@ -205,7 +211,7 @@ public:
       resp3::add_bulk(payload_, key);
 
       for (; begin != end; ++begin)
-	 resp3::add_bulk(payload_, *begin);
+         resp3::add_bulk(payload_, *begin);
 
       check_cmd(cmd);
    }
@@ -213,37 +219,39 @@ public:
    /** @brief Appends a new command to the end of the request.
     *
     *  This overload is useful for commands that have a dynamic number
-    *  of arguments and don't have a key. For example
+    *  of arguments and don't have a key. For example:
     *
-    *  \code
+    *  @code
     *  std::set<std::string> channels
-    *     { "channel1" , "channel2" , "channel3" }
+    *     { "channel1" , "channel2" , "channel3" };
     *
     *  request req;
     *  req.push("SUBSCRIBE", std::cbegin(channels), std::cend(channels));
-    *  \endcode
+    *  @endcode
     *
-    *  \param cmd The Redis command
-    *  \param begin Iterator to the begin of the range.
-    *  \param end Iterator to the end of the range.
-    *  \tparam ForwardIterator If the value type is not a std::string it will be converted to a string by calling `boost_redis_to_bulk`. This function must be made available over ADL and must have the following signature
+    *  Command arguments should either be convertible to `std::string_view`
+    *  or support the `boost_redis_to_bulk` function.
+    *  This function is a customization point that must be made available
+    *  using ADL and must have the following signature:
     *
     *  @code
     *  void boost_redis_to_bulk(std::string& to, T const& t);
-    *  {
-    *     boost::redis::resp3::boost_redis_to_bulk(to, serialize(t));
-    *  }
     *  @endcode
+    *  
+    *  @param cmd The command to execute. It should be a redis or sentinel command, like `"SET"`.
+    *  @param begin Iterator to the begin of the range.
+    *  @param end Iterator to the end of the range.
+    *  @tparam ForwardIterator A forward iterator with an element type that is convertible to `std::string_view`
+    *          or supports `boost_redis_to_bulk`.
     *
     *  See cpp20_serialization.cpp
     */
    template <class ForwardIterator>
-   void
-   push_range(
-      std::string_view const& cmd,
+   void push_range(
+      std::string_view cmd,
       ForwardIterator begin,
       ForwardIterator end,
-      typename std::iterator_traits<ForwardIterator>::value_type * = nullptr)
+      typename std::iterator_traits<ForwardIterator>::value_type* = nullptr)
    {
       using value_type = typename std::iterator_traits<ForwardIterator>::value_type;
 
@@ -256,7 +264,7 @@ public:
       resp3::add_bulk(payload_, cmd);
 
       for (; begin != end; ++begin)
-	 resp3::add_bulk(payload_, *begin);
+         resp3::add_bulk(payload_, *begin);
 
       check_cmd(cmd);
    }
@@ -265,19 +273,20 @@ public:
     *  
     *  Equivalent to the overload taking a range of begin and end
     *  iterators.
-    *
-    *  \param cmd Redis command.
-    *  \param key Redis key.
-    *  \param range Range to send e.g. `std::map`.
-    *  \tparam A type that can be passed to `std::cbegin()` and `std::cend()`.
+    *  
+    *  @param cmd The command to execute. It should be a redis or sentinel command, like `"SET"`.
+    *  @param key The command key. It will be added as the first argument to the command.
+    *  @param range Range containing the command arguments.
+    *  @tparam Range A type that can be passed to `std::begin()` and `std::end()` to obtain
+    *          iterators. The range elements should be convertible to `std::string_view`
+    *          or support `boost_redis_to_bulk`.
     */
    template <class Range>
-   void
-   push_range(
-      std::string_view const& cmd,
-      std::string_view const& key,
+   void push_range(
+      std::string_view cmd,
+      std::string_view key,
       Range const& range,
-      decltype(std::begin(range)) * = nullptr)
+      decltype(std::begin(range))* = nullptr)
    {
       using std::begin;
       using std::end;
@@ -288,17 +297,18 @@ public:
     *
     *  Equivalent to the overload taking a range of begin and end
     *  iterators.
-    *
-    *  \param cmd Redis command.
-    *  \param range Range to send e.g. `std::map`.
-    *  \tparam A type that can be passed to `std::cbegin()` and `std::cend()`.
+    *  
+    *  @param cmd The command to execute. It should be a redis or sentinel command, like `"SET"`.
+    *  @param range Range containing the command arguments.
+    *  @tparam Range A type that can be passed to `std::begin()` and `std::end()` to obtain
+    *          iterators. The range elements should be convertible to `std::string_view`
+    *          or support `boost_redis_to_bulk`.
     */
    template <class Range>
-   void
-   push_range(
+   void push_range(
       std::string_view cmd,
       Range const& range,
-      decltype(std::cbegin(range)) * = nullptr)
+      decltype(std::cbegin(range))* = nullptr)
    {
       using std::cbegin;
       using std::cend;
@@ -324,6 +334,6 @@ private:
    bool has_hello_priority_ = false;
 };
 
-} // boost::redis::resp3
+}  // namespace boost::redis
 
-#endif // BOOST_REDIS_REQUEST_HPP
+#endif  // BOOST_REDIS_REQUEST_HPP

include/boost/redis/resp3/impl/parser.ipp

@@ -1,66 +1,46 @@
-/* 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/resp3/parser.hpp>
 #include <boost/redis/error.hpp>
+#include <boost/redis/resp3/parser.hpp>
+
 #include <boost/assert.hpp>
 
 #include <charconv>
+#include <cstddef>
 #include <limits>
 
 namespace boost::redis::resp3 {
 
-void to_int(int_type& i, std::string_view sv, system::error_code& ec)
+void to_int(std::size_t& i, std::string_view sv, system::error_code& ec)
 {
    auto const res = std::from_chars(sv.data(), sv.data() + std::size(sv), i);
    if (res.ec != std::errc())
       ec = error::not_a_number;
 }
 
-parser::parser()
-{
-   reset();
-}
+parser::parser() { reset(); }
 
 void parser::reset()
 {
    depth_ = 0;
-   sizes_ = {{1}};
-   bulk_length_ = (std::numeric_limits<unsigned long>::max)();
+   sizes_ = default_sizes;
+   bulk_length_ = default_bulk_length;
    bulk_ = type::invalid;
    consumed_ = 0;
-   sizes_[0] = 2; // The sentinel must be more than 1.
 }
 
-std::size_t
-parser::get_suggested_buffer_growth(std::size_t hint) const noexcept
-{
-   if (!bulk_expected())
-      return hint;
+std::size_t parser::get_consumed() const noexcept { return consumed_; }
 
-   if (hint < bulk_length_ + 2)
-      return bulk_length_ + 2;
-
-   return hint;
-}
-
-std::size_t
-parser::get_consumed() const noexcept
-{
-   return consumed_;
-}
-
-bool
-parser::done() const noexcept
+bool parser::done() const noexcept
 {
    return depth_ == 0 && bulk_ == type::invalid && consumed_ != 0;
 }
 
-void
-parser::commit_elem() noexcept
+void parser::commit_elem() noexcept
 {
    --sizes_[depth_];
    while (sizes_[depth_] == 0) {
@@ -69,15 +49,14 @@ parser::commit_elem() noexcept
    }
 }
 
-auto
-parser::consume(std::string_view view, system::error_code& ec) noexcept -> parser::result
+auto parser::consume(std::string_view view, system::error_code& ec) noexcept -> parser::result
 {
    switch (bulk_) {
       case type::invalid:
       {
          auto const pos = view.find(sep, consumed_);
          if (pos == std::string::npos)
-            return {}; // Needs more data to proceeed.
+            return {};  // Needs more data to proceeed.
 
          auto const t = to_type(view.at(consumed_));
          auto const content = view.substr(consumed_ + 1, pos - 1 - consumed_);
@@ -88,14 +67,14 @@ parser::consume(std::string_view view, system::error_code& ec) noexcept -> parse
          consumed_ = pos + 2;
          if (!bulk_expected())
             return ret;
+      }
+         [[fallthrough]];
 
-      } [[fallthrough]];
-
-      default: // Handles bulk.
+      default:  // Handles bulk.
       {
          auto const span = bulk_length_ + 2;
          if ((std::size(view) - consumed_) < span)
-            return {}; // Needs more data to proceeed.
+            return {};  // Needs more data to proceeed.
 
          auto const bulk_view = view.substr(consumed_, bulk_length_);
          node_type const ret = {bulk_, 1, depth_, bulk_view};
@@ -108,11 +87,8 @@ parser::consume(std::string_view view, system::error_code& ec) noexcept -> parse
    }
 }
 
-auto
-parser::consume_impl(
-   type t,
-   std::string_view elem,
-   system::error_code& ec) -> parser::node_type
+auto parser::consume_impl(type t, std::string_view elem, system::error_code& ec)
+   -> parser::node_type
 {
    BOOST_ASSERT(!bulk_expected());
 
@@ -120,13 +96,13 @@ parser::consume_impl(
    switch (t) {
       case type::streamed_string_part:
       {
-         to_int(bulk_length_ , elem, ec);
+         to_int(bulk_length_, elem, ec);
          if (ec)
             return {};
 
          if (bulk_length_ == 0) {
             ret = {type::streamed_string_part, 1, depth_, {}};
-            sizes_[depth_] = 1; // We are done.
+            sizes_[depth_] = 1;  // We are done.
             bulk_ = type::invalid;
             commit_elem();
          } else {
@@ -145,7 +121,7 @@ parser::consume_impl(
             sizes_[++depth_] = (std::numeric_limits<std::size_t>::max)();
             ret = {type::streamed_string, 0, depth_, {}};
          } else {
-            to_int(bulk_length_ , elem , ec);
+            to_int(bulk_length_, elem, ec);
             if (ec)
                return {};
 
@@ -155,13 +131,13 @@ parser::consume_impl(
       case type::boolean:
       {
          if (std::empty(elem)) {
-             ec = error::empty_field;
-             return {};
+            ec = error::empty_field;
+            return {};
          }
 
          if (elem.at(0) != 'f' && elem.at(0) != 't') {
-             ec = error::unexpected_bool_value;
-             return {};
+            ec = error::unexpected_bool_value;
+            return {};
          }
 
          ret = {t, 1, depth_, elem};
@@ -172,10 +148,11 @@ parser::consume_impl(
       case type::number:
       {
          if (std::empty(elem)) {
-             ec = error::empty_field;
-             return {};
+            ec = error::empty_field;
+            return {};
          }
-      } [[fallthrough]];
+      }
+         [[fallthrough]];
       case type::simple_error:
       case type::simple_string:
       case type::null:
@@ -189,7 +166,7 @@ parser::consume_impl(
       case type::attribute:
       case type::map:
       {
-         int_type l = -1;
+         std::size_t l = static_cast<std::size_t>(-1);
          to_int(l, elem, ec);
          if (ec)
             return {};
@@ -217,4 +194,13 @@ parser::consume_impl(
 
    return ret;
 }
-} // boost::redis::resp3
+
+bool parser::is_parsing() const noexcept
+{
+   auto const v = depth_ == 0 && sizes_ == default_sizes && bulk_length_ == default_bulk_length &&
+                  bulk_ == type::invalid && consumed_ == 0;
+
+   return !v;
+}
+
+}  // namespace boost::redis::resp3

include/boost/redis/resp3/impl/serialization.ipp

@@ -1,11 +1,11 @@
-/* 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/resp3/serialization.hpp>
 #include <boost/redis/resp3/parser.hpp>
+#include <boost/redis/resp3/serialization.hpp>
 
 namespace boost::redis::resp3 {
 
@@ -35,8 +35,5 @@ void add_blob(std::string& payload, std::string_view blob)
    payload += parser::sep;
 }
 
-void add_separator(std::string& payload)
-{
-   payload += parser::sep;
-}
-} // boost::redis::resp3
+void add_separator(std::string& payload) { payload += parser::sep; }
+}  // namespace boost::redis::resp3

include/boost/redis/resp3/impl/type.ipp

@@ -1,10 +1,11 @@
-/* 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/resp3/type.hpp>
+
 #include <boost/assert.hpp>
 
 namespace boost::redis::resp3 {
@@ -12,24 +13,24 @@ namespace boost::redis::resp3 {
 auto to_string(type t) noexcept -> char const*
 {
    switch (t) {
-      case type::array: return "array";
-      case type::push: return "push";
-      case type::set: return "set";
-      case type::map: return "map";
-      case type::attribute: return "attribute";
-      case type::simple_string: return "simple_string";
-      case type::simple_error: return "simple_error";
-      case type::number: return "number";
-      case type::doublean: return "doublean";
-      case type::boolean: return "boolean";
-      case type::big_number: return "big_number";
-      case type::null: return "null";
-      case type::blob_error: return "blob_error";
-      case type::verbatim_string: return "verbatim_string";
-      case type::blob_string: return "blob_string";
-      case type::streamed_string: return "streamed_string";
+      case type::array:                return "array";
+      case type::push:                 return "push";
+      case type::set:                  return "set";
+      case type::map:                  return "map";
+      case type::attribute:            return "attribute";
+      case type::simple_string:        return "simple_string";
+      case type::simple_error:         return "simple_error";
+      case type::number:               return "number";
+      case type::doublean:             return "doublean";
+      case type::boolean:              return "boolean";
+      case type::big_number:           return "big_number";
+      case type::null:                 return "null";
+      case type::blob_error:           return "blob_error";
+      case type::verbatim_string:      return "verbatim_string";
+      case type::blob_string:          return "blob_string";
+      case type::streamed_string:      return "streamed_string";
       case type::streamed_string_part: return "streamed_string_part";
-      default: return "invalid";
+      default:                         return "invalid";
    }
 }
 
@@ -39,4 +40,4 @@ auto operator<<(std::ostream& os, type t) -> std::ostream&
    return os;
 }
 
-} // boost::redis::resp3
+}  // namespace boost::redis::resp3

include/boost/redis/resp3/node.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)
@@ -11,16 +11,13 @@
 
 namespace boost::redis::resp3 {
 
-/** \brief A node in the response tree.
- *  \ingroup high-level-api
+/** @brief A node in the response tree.
  *
- *  RESP3 can contain recursive data structures: A map of sets of
- *  vector of etc. As it is parsed each element is passed to user
- *  callbacks (push parser). The signature of this
- *  callback is `f(resp3::node<std::string_view)`. This class is called a node
+ *  RESP3 can contain recursive data structures, like a map of sets of
+ *  vectors. This class is called a node
  *  because it can be seen as the element of the response tree. It
- *  is a template so that users can use it with owing strings e.g.
- *  `std::string` or `boost::static_string` etc.
+ *  is a template so that users can use it with any string type, like
+ *  `std::string` or `boost::static_string`.
  *
  *  @tparam String A `std::string`-like type.
  */
@@ -48,17 +45,20 @@ struct basic_node {
 template <class String>
 auto operator==(basic_node<String> const& a, basic_node<String> const& b)
 {
+   // clang-format off
    return a.aggregate_size == b.aggregate_size
        && a.depth == b.depth
        && a.data_type == b.data_type
        && a.value == b.value;
+   // clang-format on
 };
 
-/** @brief A node in the response tree.
- *  @ingroup high-level-api
- */
+/// A node in the response tree that owns its data.
 using node = basic_node<std::string>;
 
-} // boost::redis::resp3
+/// A node in the response tree that does not own its data.
+using node_view = basic_node<std::string_view>;
 
-#endif // BOOST_REDIS_RESP3_NODE_HPP
+}  // namespace boost::redis::resp3
+
+#endif  // BOOST_REDIS_RESP3_NODE_HPP

include/boost/redis/resp3/parser.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)
@@ -8,16 +8,16 @@
 #define BOOST_REDIS_RESP3_PARSER_HPP
 
 #include <boost/redis/resp3/node.hpp>
+
 #include <boost/system/error_code.hpp>
+
 #include <array>
-#include <string_view>
 #include <cstdint>
 #include <optional>
+#include <string_view>
 
 namespace boost::redis::resp3 {
 
-using int_type = std::uint64_t;
-
 class parser {
 public:
    using node_type = basic_node<std::string_view>;
@@ -27,6 +27,14 @@ public:
    static constexpr std::string_view sep = "\r\n";
 
 private:
+   using sizes_type = std::array<std::size_t, max_embedded_depth + 1>;
+
+   // sizes_[0] = 2 because the sentinel must be more than 1.
+   static constexpr sizes_type default_sizes = {
+      {2, 1, 1, 1, 1, 1}
+   };
+   static constexpr auto default_bulk_length = static_cast<std::size_t>(-1);
+
    // The current depth. Simple data types will have depth 0, whereas
    // the elements of aggregates will have depth 1. Embedded types
    // will have increasing depth.
@@ -35,10 +43,10 @@ private:
    // The parser supports up to 5 levels of nested structures. The
    // first element in the sizes stack is a sentinel and must be
    // different from 1.
-   std::array<std::size_t, max_embedded_depth + 1> sizes_;
+   sizes_type sizes_;
 
    // Contains the length expected in the next bulk read.
-   int_type bulk_length_;
+   std::size_t bulk_length_;
 
    // The type of the next bulk. Contains type::invalid if no bulk is
    // expected.
@@ -56,7 +64,9 @@ private:
    // returns type::invalid.
    [[nodiscard]]
    auto bulk_expected() const noexcept -> bool
-      { return bulk_ != type::invalid; }
+   {
+      return bulk_ != type::invalid;
+   }
 
 public:
    parser();
@@ -65,26 +75,26 @@ public:
    [[nodiscard]]
    auto done() const noexcept -> bool;
 
-   auto get_suggested_buffer_growth(std::size_t hint) const noexcept -> std::size_t;
-
    auto get_consumed() const noexcept -> std::size_t;
 
    auto consume(std::string_view view, system::error_code& ec) noexcept -> result;
 
    void reset();
+
+   bool is_parsing() const noexcept;
 };
 
 // Returns false if more data is needed. If true is returned the
 // parser is either done or an error occured, that can be checked on
 // ec.
 template <class Adapter>
-bool
-parse(
-   resp3::parser& p,
-   std::string_view const& msg,
-   Adapter& adapter,
-   system::error_code& ec)
+bool parse(parser& p, std::string_view const& msg, Adapter& adapter, system::error_code& ec)
 {
+   // This if could be avoid with a state machine that jumps into the
+   // correct position.
+   if (!p.is_parsing())
+      adapter.on_init();
+
    while (!p.done()) {
       auto const res = p.consume(msg, ec);
       if (ec)
@@ -93,14 +103,15 @@ parse(
       if (!res)
          return false;
 
-      adapter(res.value(), ec);
+      adapter.on_node(res.value(), ec);
       if (ec)
          return true;
    }
 
+   adapter.on_done();
    return true;
 }
 
-} // boost::redis::resp3
+}  // namespace boost::redis::resp3
 
-#endif // BOOST_REDIS_RESP3_PARSER_HPP
+#endif  // BOOST_REDIS_RESP3_PARSER_HPP

include/boost/redis/resp3/serialization.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)
@@ -7,10 +7,11 @@
 #ifndef BOOST_REDIS_RESP3_SERIALIZATION_HPP
 #define BOOST_REDIS_RESP3_SERIALIZATION_HPP
 
+#include <boost/redis/resp3/parser.hpp>
 #include <boost/redis/resp3/type.hpp>
+
 #include <boost/system/system_error.hpp>
 #include <boost/throw_exception.hpp>
-#include <boost/redis/resp3/parser.hpp>
 
 #include <string>
 #include <tuple>
@@ -36,8 +37,6 @@ namespace boost::redis::resp3 {
  *
  *  @param payload Storage on which data will be copied into.
  *  @param data Data that will be serialized and stored in `payload`.
- *
- *  See more in @ref serialization.
  */
 void boost_redis_to_bulk(std::string& payload, std::string_view data);
 
@@ -57,12 +56,11 @@ struct add_bulk_impl {
    }
 };
 
-template <class ...Ts>
+template <class... Ts>
 struct add_bulk_impl<std::tuple<Ts...>> {
    static void add(std::string& payload, std::tuple<Ts...> const& t)
    {
-      auto f = [&](auto const&... vs)
-      {
+      auto f = [&](auto const&... vs) {
          using namespace boost::redis::resp3;
          (boost_redis_to_bulk(payload, vs), ...);
       };
@@ -94,23 +92,24 @@ struct bulk_counter;
 
 template <class>
 struct bulk_counter {
-  static constexpr auto size = 1U;
+   static constexpr auto size = 1U;
 };
 
 template <class T, class U>
 struct bulk_counter<std::pair<T, U>> {
-  static constexpr auto size = 2U;
+   static constexpr auto size = 2U;
 };
 
 void add_blob(std::string& payload, std::string_view blob);
 void add_separator(std::string& payload);
 
-namespace detail
-{
+namespace detail {
 
 template <class Adapter>
 void deserialize(std::string_view const& data, Adapter adapter, system::error_code& ec)
 {
+   adapter.on_init();
+
    parser parser;
    while (!parser.done()) {
       auto const res = parser.consume(data, ec);
@@ -119,12 +118,14 @@ void deserialize(std::string_view const& data, Adapter adapter, system::error_co
 
       BOOST_ASSERT(res.has_value());
 
-      adapter(res.value(), ec);
+      adapter.on_node(res.value(), ec);
       if (ec)
          return;
    }
 
    BOOST_ASSERT(parser.get_consumed() == std::size(data));
+
+   adapter.on_done();
 }
 
 template <class Adapter>
@@ -134,11 +135,11 @@ void deserialize(std::string_view const& data, Adapter adapter)
    deserialize(data, adapter, ec);
 
    if (ec)
-       BOOST_THROW_EXCEPTION(system::system_error{ec});
+      BOOST_THROW_EXCEPTION(system::system_error{ec});
 }
 
-}
+}  // namespace detail
 
-} // boost::redis::resp3
+}  // namespace boost::redis::resp3
 
-#endif // BOOST_REDIS_RESP3_SERIALIZATION_HPP
+#endif  // BOOST_REDIS_RESP3_SERIALIZATION_HPP

include/boost/redis/resp3/type.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)
@@ -8,70 +8,77 @@
 #define BOOST_REDIS_RESP3_TYPE_HPP
 
 #include <boost/assert.hpp>
+
 #include <ostream>
-#include <vector>
 #include <string>
+#include <vector>
 
 namespace boost::redis::resp3 {
 
-/** \brief RESP3 data types.
-    \ingroup high-level-api
+/** @brief RESP3 data types.
   
-    The RESP3 specification can be found at https://github.com/redis/redis-specifications/blob/master/protocol/RESP3.md.
+    The RESP3 specification can be found at
+    <a href="https://github.com/redis/redis-specifications/blob/master/protocol/RESP3.md"></a>
  */
 enum class type
-{ /// Aggregate
-  array,
-  /// Aaggregate
-  push,
-  /// Aggregate
-  set,
-  /// Aggregate
-  map,
-  /// Aggregate
-  attribute,
-  /// Simple
-  simple_string,
-  /// Simple
-  simple_error,
-  /// Simple
-  number,
-  /// Simple
-  doublean,
-  /// Simple
-  boolean,
-  /// Simple
-  big_number,
-  /// Simple
-  null,
-  /// Simple
-  blob_error,
-  /// Simple
-  verbatim_string,
-  /// Simple
-  blob_string,
-  /// Simple
-  streamed_string,
-  /// Simple
-  streamed_string_part,
-  /// Invalid
-  invalid
+{  /// Aggregate
+   array,
+   /// Aaggregate
+   push,
+   /// Aggregate
+   set,
+   /// Aggregate
+   map,
+   /// Aggregate
+   attribute,
+   /// Simple
+   simple_string,
+   /// Simple
+   simple_error,
+   /// Simple
+   number,
+   /// Simple
+   doublean,
+   /// Simple
+   boolean,
+   /// Simple
+   big_number,
+   /// Simple
+   null,
+   /// Simple
+   blob_error,
+   /// Simple
+   verbatim_string,
+   /// Simple
+   blob_string,
+   /// Simple
+   streamed_string,
+   /// Simple
+   streamed_string_part,
+   /// Invalid
+   invalid
 };
 
-/** \brief Converts the data type to a string.
- *  \ingroup high-level-api
- *  \param t RESP3 type.
+/** @brief Converts the data type to a string.
+ *
+ *  @relates type
+ *  @param t The type to convert.
  */
 auto to_string(type t) noexcept -> char const*;
 
-/** \brief Writes the type to the output stream.
- *  \ingroup high-level-api
- *  \param os Output stream.
- *  \param t RESP3 type.
+/** @brief Writes the type to the output stream.
+ *
+ *  @relates type
+ *  @param os Output stream.
+ *  @param t The type to stream.
  */
 auto operator<<(std::ostream& os, type t) -> std::ostream&;
 
-/* Checks whether the data type is an aggregate.
+/** @brief Checks whether the data type is an aggregate.
+ *  
+ *  @relates type
+ *  @param t The type to check.
+ *  @returns True if the given type is an aggregate.
  */
 constexpr auto is_aggregate(type t) noexcept -> bool
 {
@@ -81,7 +88,7 @@ constexpr auto is_aggregate(type t) noexcept -> bool
       case type::set:
       case type::map:
       case type::attribute: return true;
-      default: return false;
+      default:              return false;
    }
 }
 
@@ -92,7 +99,7 @@ constexpr auto element_multiplicity(type t) noexcept -> std::size_t
    switch (t) {
       case type::map:
       case type::attribute: return 2ULL;
-      default: return 1ULL;
+      default:              return 1ULL;
    }
 }
 
@@ -141,10 +148,10 @@ constexpr auto to_type(char c) noexcept -> type
       case '*': return type::array;
       case '|': return type::attribute;
       case '%': return type::map;
-      default: return type::invalid;
+      default:  return type::invalid;
    }
 }
 
-} // boost::redis::resp3
+}  // namespace boost::redis::resp3
 
-#endif // BOOST_REDIS_RESP3_TYPE_HPP
+#endif  // BOOST_REDIS_RESP3_TYPE_HPP