Add support for modular build structure. (#204)

* Fixes issue 181.

* Refactors add_hello and adds unit tests.

* Adds endian to the list of dependencies

* Make the library modular usable.

* Some fixes in the article about the costs of async abstractions [skip ci]

* Switch to library requirements instead of source. As source puts extra source in install targets.

* Add missing import-search for cconfig/predef checks.

* Add requires-b2 check to top-level build file.

* Bump B2 require to 5.2

* Move inter-lib dependencies to a project variable and into the build targets.

* Update build deps.

* Fix spurious semi-colon.

---------

Co-authored-by: Marcelo Zimbres <mzimbres@gmail.com>

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
+    ;
+

test/Jamfile

@@ -1,5 +1,6 @@
 
-import ../config/checks/config : requires ;
+import-search /boost/config/checks ;
+import config : requires ;
 import ac ;
 
 # Configure openssl if it hasn't been done yet
@@ -7,6 +8,7 @@ using openssl ;
 
 # Use these requirements as both regular and usage requirements across all tests
 local requirements =
+        <library>/boost/redis//boost_redis
         <define>BOOST_ASIO_NO_DEPRECATED=1
         <define>BOOST_ASIO_DISABLE_BOOST_ARRAY=1
         <define>BOOST_ASIO_DISABLE_BOOST_BIND=1
@@ -14,7 +16,6 @@ local requirements =
         <define>BOOST_ASIO_DISABLE_BOOST_REGEX=1
         <toolset>msvc:<cxxflags>"/bigobj"
         <target-os>windows:<define>_WIN32_WINNT=0x0601
-        <include>../include
         [ requires
             cxx14_constexpr
             cxx14_generic_lambdas
@@ -30,6 +31,7 @@ local requirements =
         ]
         [ ac.check-library /openssl//ssl    : <library>/openssl//ssl/<link>shared : <build>no ]
         [ ac.check-library /openssl//crypto : <library>/openssl//crypto/<link>shared : <build>no ]
+        <library>/boost/test//boost_unit_test_framework
     ;