HTTP WebSocket Classes basic_headers basic_parser_v1 basic_streambuf_body empty_body error_code headers message resume_context streambuf_body string_body Type Traits is_Parser Functions async_read async_write prepare read write Constants connection Concepts Body Field FieldSequence Reader Writer Classes close_reason stream Options auto_fragment_size decorate keep_alive read_buffer_size read_message_max write_buffer_size Functions async_teardown teardown Constants close_code opcode Core Classes async_completion basic_streambuf buffers_adapter consuming_buffers handler_alloc prepared_buffers static_streambuf static_streambuf_n static_string streambuf streambuf_readstream Functions bind_handler buffer_cat consumed_buffers prepare_buffer prepare_buffers to_string write Type Traits is_AsyncReadStream is_AsyncWriteStream is_AsyncStream is_BufferSequence is_CompletionHandler is_ConstBufferSequence is_MutableBufferSequence is_Streambuf is_SyncReadStream is_SyncStream is_SyncWriteStream Concepts BufferSequence AsyncStream Stream Streambuf SyncStream Diagnostic doc_debug nested_doc_debug