fix#1417
* New get_lowest_layer free function works for any object
* New lowest_layer_type trait works for any object
* New examples and documentation on layered streams
API Changes:
* The member function lowest_layer is removed from all
types provided by the library:
Actions Required:
* Call the free function get_lowest_layer instead of
member lowest_layer.
fix#884
* BodyReader and BodyWriter constructors now require the header and
body elements to be passed as distinct header and value_type objects.
This enables the composition of body types, for example:
http::response<compressed_body<http::string_body>> res;
* The previous single-argument constructors are deprecated and will be
removed in a subsequent version.
Actions Required:
* Change user-defined instances of BodyReader or BodyWriter constructor
signatures to the two-argument form.
OR
* Define the macro BOOST_BEAST_ALLOW_DEPRECATED in the project (which
will accept both the new and the deprecated signatures).
Body::reader and Body::writer meanings are reversed, for
consistency with the names of the stream operations:
* Body::reader is used for read, read_some, async_read, async_read_some
* Body::writer is used for write, write_some, async_write, async_write_some
Actions Required:
* Swap the reader and writer names for user defined Body types
* Swap use of is_body_reader and is_body_writer
* Fields::writer replaces Fields::reader
* The FieldsWriter concept is renamed from FieldsReader
Actions Required:
* Rename reader to writer for user defined Fields
* The function has_content_length_impl is added to the
requirements of Fields.
Actions Required:
* Implement has_content_length_impl for user-defined Fields
fix#769
The following classes are removed:
* handler_type
* async_result
* async_completion
* is_dynamic_buffer
* is_const_buffer_sequence
* is_mutable_buffer_sequence
* handler_alloc
Actions Required:
* Use BOOST_ASIO_HANDLER_TYPE instead of handler_type
* Use BOOST_ASIO_INITFN_RESULT_TYPE instead of async_result
* Use boost::asio::async_completion
* Use boost::asio::is_dynamic_buffer
* Use boost::asio::is_const_buffer_sequence
* Use boost::asio::is_mutable_buffer_sequence
* boost::asio::associated_allocator_t replaces handler_alloc
* The drain_buffer dynamic buffer is no longer a public interface.
Actions Required:
* Replace code which uses drain_buffer. For websocket::stream,
it is no longer necessary to manually drain the connection
after closing.
New buffer sequence classes are provided to allow full
control over the serialization of chunk-encoded message
payloads:
* chunk_header
A ConstBufferSequence representing the chunk header.
It includes a hexadecimal-encoded size, an optional
set of chunk extensions, and the trailing CRLF
required to denote the end of the chunk header.
This allows the caller to manually serialize the chunk
body in one or more calls to a stream output function.
The caller must also output an object of type `chunk_crlf`
to the stream to indicate the end of the chunk body.
* chunk_crlf
A small ConstBufferSequence that simply represents
the two character sequence "\r\n" (CRLF). This is needed
for the case where the caller wants to output a chunk
body as a series of buffers (i.e. "chunking a chunk").
* chunk_body
A ConstBufferSequence representing a complete chunk.
This includes the size, an optional set of chunk extensions,
a caller provided buffer containing the body, and the
required CRLF that follows.
* chunk_final
A ConstBufferSequence representing a final chunk. It
includes an optional set of caller-provided field trailers
* chunk_extensions
A container for building a set of chunk extensions to use
during serialization. The use of the container is optional,
callers may provide their own buffer containing a correctly
formatted set of chunk extensions, or they may use their
own convenience container which meets the requirements.
The basic_fields container is modified to allow construction
outside the context of a message. The container can be used
to provide trailers to `chunk_final`.
Actions Required:
* Remove references to ChunkDecorators. Use the new chunk-encoding
buffer sequences to manually produce a chunked payload body in
the case where control over the chunk-extensions and/or trailers
is required.
