Add C++20 module support

CMakeLists.txt

@@ -37,6 +37,7 @@ if (BOOST_BEAST_IS_ROOT)
 endif ()
 option(BOOST_BEAST_BUILD_TESTS "Build boost::beast tests" ${BUILD_TESTING})
 option(BOOST_BEAST_BUILD_FUZZERS "Build boost::beast fuzzers" OFF)
+option(BOOST_BEAST_BUILD_MODULES "Build boost::beast modules (requires C++20)" OFF)
 option(BOOST_BEAST_BUILD_EXAMPLES "Build boost::beast examples" ${BOOST_BEAST_IS_ROOT})
 option(BOOST_BEAST_WARNINGS_AS_ERRORS "Treat warnings as errors" OFF)
 
@@ -163,6 +164,15 @@ if (BOOST_BEAST_BUILD_TESTS)
     add_subdirectory(test)
 endif ()
 
+#-------------------------------------------------
+#
+# Modules
+#
+#-------------------------------------------------
+if (BOOST_BEAST_BUILD_MODULES)
+    add_subdirectory(modules)
+endif ()
+
 #-------------------------------------------------
 #
 # Examples

module/CMakeLists.txt

@@ -0,0 +1,27 @@
+cmake_minimum_required(VERSION 3.28)
+
+add_library(boost_beast_module)
+
+target_sources(boost_beast_module
+    PUBLIC
+        FILE_SET CXX_MODULES FILES
+            boost.cppm
+)
+
+target_compile_features(boost_beast_module PUBLIC cxx_std_20)
+
+target_include_directories(boost_beast_module PUBLIC
+    $<BUILD_INTERFACE:${PROJECT_SOURCE_DIR}/include>
+    $<INSTALL_INTERFACE:include>
+)
+
+add_library(Boost::beast::module ALIAS boost_beast_module)
+
+# Installation
+install(TARGETS boost_beast_module
+    EXPORT ${PROJECT_NAME}Targets
+    LIBRARY DESTINATION ${CMAKE_INSTALL_LIBDIR}
+    ARCHIVE DESTINATION ${CMAKE_INSTALL_LIBDIR}
+    RUNTIME DESTINATION ${CMAKE_INSTALL_BINDIR}
+    FILE_SET CXX_MODULES DESTINATION ${CMAKE_INSTALL_INCLUDEDIR}/module
+)

module/beast.cppm

@@ -0,0 +1,254 @@
+//
+// Copyright (c) 2016-2026 Vinnie Falco (vinnie dot falco 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)
+//
+// Official repository: https://github.com/boostorg/beast
+//
+
+module;
+
+#include <boost/beast.hpp>
+#include <boost/beast/core/buffer_traits.hpp>
+#include <boost/beast/_experimental/http/icy_stream.hpp>
+#include <boost/beast/_experimental/test/error.hpp>
+#include <boost/beast/_experimental/test/fail_count.hpp>
+#include <boost/beast/_experimental/test/handler.hpp>
+#include <boost/beast/_experimental/test/stream.hpp>
+
+export module boost.beast;
+
+export namespace boost::beast {
+    using boost::beast::async_base;
+    using boost::beast::basic_stream;
+    using boost::beast::file;
+    using boost::beast::file_mode;
+    #if BOOST_BEAST_USE_POSIX_FILE
+    using boost::beast::file_posix;
+    #endif
+    using boost::beast::file_stdio;
+    #if BOOST_BEAST_USE_WIN32_FILE
+    using boost::beast::file_win32;
+    #endif
+    using boost::beast::flat_stream;
+    using boost::beast::iequal;
+    using boost::beast::iless;
+    using boost::beast::rate_policy_access;
+    using boost::beast::saved_handler;
+    using boost::beast::simple_rate_policy;
+    using boost::beast::static_string;
+    using boost::beast::stable_async_base;
+    using boost::beast::string_view;
+    using boost::beast::tcp_stream;
+    using boost::beast::unlimited_rate_policy;
+
+    using boost::beast::condition;
+    using boost::beast::error;
+    using boost::beast::file_mode;
+    using boost::beast::role_type;
+
+    using boost::beast::allocate_stable;
+    using boost::beast::async_detect_ssl;
+    using boost::beast::beast_close_socket;
+    using boost::beast::bind_front_handler;
+    using boost::beast::bind_handler;
+
+    template <class Socket>
+    inline void close_socket(Socket& sock) {
+        boost::beast::close_socket(sock);
+    }
+
+    using boost::beast::detect_ssl;
+    using boost::beast::generic_category;
+    using boost::beast::get_lowest_layer;
+    using boost::beast::iequals;
+    using boost::beast::to_static_string;
+
+    using boost::beast::executor_type;
+    using boost::beast::has_get_executor;
+    using boost::beast::is_async_read_stream;
+    template <class T>
+    using is_async_stream = std::integral_constant<bool,
+        is_async_read_stream<T>::value && is_async_write_stream<T>::value>;
+    using boost::beast::is_async_write_stream;
+
+    using boost::beast::is_file;
+    using boost::beast::is_sync_read_stream;
+    template <class T>
+    using is_sync_stream = std::integral_constant<bool,
+        is_sync_read_stream<T>::value && is_sync_write_stream<T>::value>;
+    using boost::beast::is_sync_write_stream;
+    // using boost::beast::lowest_layer_type;
+
+    // using boost::beast::ssl_stream;
+
+    namespace errc = boost::beast::errc;
+    using boost::beast::error_category;
+    using boost::beast::error_code;
+    using boost::beast::error_condition;
+    using boost::beast::system_category;
+    using boost::beast::system_error;
+
+    using boost::beast::basic_flat_buffer;
+    using boost::beast::basic_multi_buffer;
+    // using boost::beast::buffer_ref;
+    using boost::beast::buffered_read_stream;
+    using boost::beast::buffers_adaptor;
+    using boost::beast::buffers_cat_view;
+    using boost::beast::buffers_prefix_view;
+    using boost::beast::buffers_prefix_view;
+    using boost::beast::buffers_suffix;
+    using boost::beast::flat_buffer;
+    using boost::beast::flat_static_buffer;
+    using boost::beast::flat_static_buffer_base;
+    using boost::beast::multi_buffer;
+    using boost::beast::static_buffer;
+    using boost::beast::static_buffer_base;
+
+    using boost::beast::async_write;
+
+    template <class BufferSequence>
+    [[nodiscard]]
+    inline std::size_t buffer_bytes(BufferSequence const& buffers) {
+        return boost::beast::buffer_bytes(buffers);
+    }
+
+    using boost::beast::buffers_cat;
+    using boost::beast::buffers_front;
+    using boost::beast::buffers_prefix;
+    using boost::beast::buffers_range;
+    using boost::beast::buffers_range_ref;
+    using boost::beast::buffers_to_string;
+    using boost::beast::make_printable;
+    using boost::beast::ostream;
+    using boost::beast::read_size;
+    using boost::beast::read_size_or_throw;
+    // using boost::beast::ref;
+    using boost::beast::write;
+
+    using boost::beast::buffers_iterator_type;
+    // using boost::beast::buffers_type;
+    using boost::beast::is_buffers_generator;
+    // using boost::beast::is_const_buffer_sequence;
+    // using boost::beast::is_mutable_buffer_sequence;
+
+    namespace http {
+        using boost::beast::http::basic_chunk_extensions;
+        using boost::beast::http::basic_dynamic_body;
+        using boost::beast::http::basic_fields;
+        using boost::beast::http::basic_file_body;
+        using boost::beast::http::basic_parser;
+        using boost::beast::http::basic_string_body;
+        using boost::beast::http::buffer_body;
+        using boost::beast::http::chunk_body;
+        using boost::beast::http::chunk_crlf;
+        using boost::beast::http::chunk_extensions;
+        using boost::beast::http::chunk_header;
+        using boost::beast::http::chunk_last;
+        using boost::beast::http::dynamic_body;
+        using boost::beast::http::empty_body;
+        using boost::beast::http::fields;
+        using boost::beast::http::file_body;
+        using boost::beast::http::header;
+        using boost::beast::http::message;
+        using boost::beast::http::message_generator;
+        using boost::beast::http::parser;
+        using boost::beast::http::request;
+        using boost::beast::http::request_header;
+        using boost::beast::http::request_serializer;
+        using boost::beast::http::response;
+        using boost::beast::http::response_header;
+        using boost::beast::http::response_parser;
+        using boost::beast::http::response_serializer;
+        using boost::beast::http::serializer;
+        using boost::beast::http::span_body;
+        using string_body = boost::beast::http::basic_string_body<char>;
+        using boost::beast::http::vector_body;
+
+        using boost::beast::http::async_read;
+        using boost::beast::http::async_read_header;
+        using boost::beast::http::async_read_some;
+        using boost::beast::http::async_write;
+        using boost::beast::http::async_write_header;
+        using boost::beast::http::async_write_some;
+        using boost::beast::http::int_to_status;
+        using boost::beast::http::make_chunk;
+        using boost::beast::http::make_chunk_last;
+        using boost::beast::http::obsolete_reason;
+        using boost::beast::http::operator<<;
+        using boost::beast::http::read;
+        using boost::beast::http::read_header;
+        using boost::beast::http::read_some;
+        using boost::beast::http::string_to_field;
+        using boost::beast::http::string_to_verb;
+        using boost::beast::http::swap;
+        using boost::beast::http::to_string;
+        using boost::beast::http::to_status_class;
+        using boost::beast::http::write;
+        using boost::beast::http::write_header;
+        using boost::beast::http::write_some;
+
+        using boost::beast::http::error;
+        using boost::beast::http::field;
+        using boost::beast::http::status;
+        using boost::beast::http::status_class;
+        using boost::beast::http::verb;
+
+        // using boost::beast::http::is_body;
+        using boost::beast::http::is_body_reader;
+        using boost::beast::http::is_body_writer;
+        using boost::beast::http::is_fields;
+        using boost::beast::http::is_mutable_body_writer;
+
+        using boost::beast::http::ext_list;
+        using boost::beast::http::opt_token_list;
+        using boost::beast::http::param_list;
+        using boost::beast::http::token_list;
+    }
+
+    namespace websocket {
+        using boost::beast::websocket::close_reason;
+        using ping_data = boost::beast::static_string<125, char>;
+        using boost::beast::websocket::stream;
+        using boost::beast::websocket::stream_base;
+        using reason_string = boost::beast::static_string<123, char>;
+
+        using boost::beast::websocket::async_teardown;
+        using boost::beast::websocket::is_upgrade;
+        using boost::beast::websocket::seed_prng;
+        using boost::beast::websocket::teardown;
+
+        using boost::beast::websocket::permessage_deflate;
+
+        using boost::beast::websocket::close_code;
+        using boost::beast::websocket::condition;
+        using boost::beast::websocket::error;
+        using boost::beast::websocket::frame_type;
+    }
+
+    namespace zlib {
+        using boost::beast::zlib::deflate_stream;
+        using boost::beast::zlib::inflate_stream;
+        using boost::beast::zlib::z_params;
+        using boost::beast::zlib::deflate_upper_bound;
+        using boost::beast::zlib::error;
+        using boost::beast::zlib::Flush;
+        using boost::beast::zlib::Strategy;
+    }
+
+    namespace http {
+        using boost::beast::http::icy_stream;
+    }
+
+    namespace test {
+        using boost::beast::test::fail_count;
+        using boost::beast::test::handler;
+        // using boost::beast::test::stream;
+        using boost::beast::test::connect;
+        using boost::beast::test::any_handler;
+        using boost::beast::test::fail_handler;
+        using boost::beast::test::success_handler;
+        using boost::beast::test::error;
+    }
+}