Add Transfer-Encoding compression support and extensible compression API

Release/CMakeLists.txt

@@ -18,6 +18,7 @@ enable_testing()
 set(WERROR ON CACHE BOOL "Treat Warnings as Errors.")
 set(CPPREST_EXCLUDE_WEBSOCKETS OFF CACHE BOOL "Exclude websockets functionality.")
 set(CPPREST_EXCLUDE_COMPRESSION OFF CACHE BOOL "Exclude compression functionality.")
+set(CPPREST_EXCLUDE_BROTLI ON CACHE BOOL "Exclude Brotli compression functionality.")
 set(CPPREST_EXPORT_DIR lib/cpprestsdk CACHE STRING "Directory to install CMake config files.")
 set(CPPREST_INSTALL_HEADERS ON CACHE BOOL "Install header files.")
 set(CPPREST_INSTALL ON CACHE BOOL "Add install commands.")
@@ -62,6 +63,7 @@ include(cmake/cpprest_find_boost.cmake)
 include(cmake/cpprest_find_zlib.cmake)
 include(cmake/cpprest_find_openssl.cmake)
 include(cmake/cpprest_find_websocketpp.cmake)
+include(cmake/cpprest_find_brotli.cmake)
 include(CheckIncludeFiles)
 include(GNUInstallDirs)
 

Release/cmake/cpprest_find_brotli.cmake

@@ -0,0 +1,10 @@
+function(cpprest_find_brotli)
+  if(TARGET cpprestsdk_brotli_internal)
+    return()
+  endif()
+
+  find_package(UNOFFICIAL-BROTLI REQUIRED)
+
+  add_library(cpprestsdk_brotli_internal INTERFACE)
+  target_link_libraries(cpprestsdk_brotli_internal INTERFACE unofficial::brotli::brotlienc unofficial::brotli::brotlidec unofficial::brotli::brotlicommon)
+endfunction()

Release/cmake/cpprestsdk-config.in.cmake

@@ -3,6 +3,10 @@ if(@CPPREST_USES_ZLIB@)
   find_dependency(ZLIB)
 endif()
 
+if(@CPPREST_USES_BROTLI@)
+  find_dependency(UNOFFICIAL-BROTLI)
+endif()
+
 if(@CPPREST_USES_OPENSSL@)
   find_dependency(OpenSSL)
 endif()

Release/include/cpprest/asyncrt_utils.h

@@ -503,7 +503,7 @@ _ASYNCRTIMP const std::error_category & __cdecl linux_category();
 
 /// <summary>
 /// Gets the one global instance of the current platform's error category.
-/// <summary>
+/// </summary>
 _ASYNCRTIMP const std::error_category & __cdecl platform_category();
 
 /// <summary>

Release/include/cpprest/details/http_helpers.h

@@ -41,70 +41,4 @@ namespace details
         _ASYNCRTIMP size_t __cdecl add_chunked_delimiters(_Out_writes_(buffer_size) uint8_t *data, _In_ size_t buffer_size, size_t bytes_read);
     }
 
-    namespace compression
-    {
-        enum class compression_algorithm : int 
-        { 
-            deflate = 15,
-            gzip = 31,
-            invalid = 9999
-        };
-
-        using data_buffer = std::vector<uint8_t>;
-
-        class stream_decompressor
-        {
-        public:
-
-            static compression_algorithm to_compression_algorithm(const utility::string_t& alg)
-            {
-                if (_XPLATSTR("gzip") == alg)
-                {
-                    return compression_algorithm::gzip;
-                }
-                else if (_XPLATSTR("deflate") == alg)
-                {
-                    return compression_algorithm::deflate;
-                }
-
-                return compression_algorithm::invalid;
-            }
-
-            static utility::string_t known_algorithms() { return _XPLATSTR("deflate, gzip"); }
-
-            _ASYNCRTIMP static bool __cdecl is_supported();
-
-            _ASYNCRTIMP stream_decompressor(compression_algorithm alg);
-
-            _ASYNCRTIMP data_buffer decompress(const data_buffer& input);
-
-            _ASYNCRTIMP data_buffer decompress(const uint8_t* input, size_t input_size);
-
-            _ASYNCRTIMP bool has_error() const;
-
-        private:
-            class stream_decompressor_impl;
-            std::shared_ptr<stream_decompressor_impl> m_pimpl;
-        };
-
-        class stream_compressor
-        {
-        public:
-
-            _ASYNCRTIMP static bool __cdecl is_supported();
-
-            _ASYNCRTIMP stream_compressor(compression_algorithm alg);
-
-            _ASYNCRTIMP data_buffer compress(const data_buffer& input, bool finish);
-
-            _ASYNCRTIMP data_buffer compress(const uint8_t* input, size_t input_size, bool finish);
-
-            _ASYNCRTIMP bool has_error() const;
-
-        private:
-            class stream_compressor_impl;
-            std::shared_ptr<stream_compressor_impl> m_pimpl;
-        };
-
-    }
 }}}

Release/include/cpprest/http_client.h

@@ -247,20 +247,22 @@ class http_client_config
     }
 
     /// <summary>
-    /// Checks if requesting a compressed response is turned on, the default is off.
+    /// Checks if requesting a compressed response using Content-Encoding is turned on, the default is off.
     /// </summary>
-    /// <returns>True if compressed response is enabled, false otherwise</returns>
+    /// <returns>True if a content-encoded compressed response is allowed, false otherwise</returns>
     bool request_compressed_response() const
     {
         return m_request_compressed;
     }
 
     /// <summary>
-    /// Request that the server responds with a compressed body.
-    /// If true, in cases where the server does not support compression, this will have no effect.
+    /// Request that the server respond with a compressed body using Content-Encoding; to use Transfer-Encoding, do not
+    /// set this, and specify a vector of <see cref="web::http::details::comporession::decompress_factory" /> pointers
+    /// to the set_decompress_factories method of the <see cref="web::http::http_request" /> object for the request.
+    /// If true and the server does not support compression, this will have no effect.
     /// The response body is internally decompressed before the consumer receives the data.
     /// </summary>
-    /// <param name="request_compressed">True to turn on response body compression, false otherwise.</param>
+    /// <param name="request_compressed">True to turn on content-encoded response body compression, false otherwise.</param>
     /// <remarks>Please note there is a performance cost due to copying the request data. Currently only supported on Windows and OSX.</remarks>
     void set_request_compressed_response(bool request_compressed)
     {