A new class `serializer` is introduced to permit incremental
serialization of HTTP messages. Existing free functions are
re-implemented in terms of this new class.
* The BodyReader concept is refined to support a greater variety
of strategies for providing buffers representing the body to
the serialization algorithms.
* Added buffer_body, a new model of Body which allows the caller
to provide a series of owned buffers using their own serialization
loop.
* Added empty_body, a model of Body which is for serialization only,
to represent HTTP messages with no content body.
* Removed overloads of write and async_write which send only
the HTTP header.
* Removed public interfaces for performing low-level chunk encoding.
The concept type traits are renamed for consistency,
and consolidated into a single header file <beast/core/type_traits.hpp>
A new section, Core Concepts, is added to the documentation describing all
of the core utility classes and functions. This also includes a complete
explanation and sample program describing how to write asynchronous initiation
functions and their associated composed operations.
This function converts integers to their decimal
representation as a static string.
In addition, static_string::resize no longer initializes
characters if the new size is larger.
A new function, buffers(), returns an implementation defined object
which wraps a ConstBufferSequence and supports formatting to a
std::ostream.
The function to_string is removed, as the new implementation allows
conversion to string using boost::lexical_cast on the return value
of the call to buffers(). Streaming to an output stream is more
efficient: no dynamic allocations are performed.
Example:
streambuf sb;
std::cout << buffers(sb.data()) << std::endl;
This eliminates beast::write output for dynamic buffers and replaces
it with the function ostream() that wraps a caller provided dynamic
buffer and returns the result as a std::ostream derived object.
Callers may now produce formatted output into any object meeting the
requirements of DynamicBuffer using operator<< and the standard stream
modifiers such as std::endl.
This new technique is more efficient, as implementations of operator<<
can now write directly into the output using std::ostream::write and
std::ostream::put.
Example of use:
beast::streambuf sb;
beast::ostream(sb) << "Hello, world!" << std::endl;
fix#124
The http::header data members "method", "url", and "reason"
are changed from data members, to pairs of get and set
functions which forward the call to the Fields type used
to instantiate the template.
Previously, these data members were implemented using
std::string. With this change, the implementation of the
Fields type used to instantiate the template is now in
control of the representation of those values. This permits
custom memory allocation strategies including uniform use of
the Allocator type already provided to beast::http::basic_fields.
fix#332
This removes the keep_alive option from the WebSocket stream.
Callers who wish to control the behavior of the Connection
header may do so in the decorator and completion handlers
for the handshake and accept functions.
fix#325
This removes unused and misleading handshake error codes.
All semantic handshake failures are now reported using
the same code, error::handshake_failed. Errors originating
from stream operations still use the underlying stream
error codes (for example: boost::asio::error::connection_reset).
fix#195
This function returns `true` when the passed HTTP Request
indicates a WebSocket Upgrade. It does not validate the
contents of the fields: it just trivially accepts requests
which can only be a WebSocket Upgrade message.
Callers who wish to manually read HTTP requests in their
server implementation can use this function to determine if
the request should be routed to an instance of websocket::stream.
fix#80, #212, fix#303, fix#314, fix#317
websocket::stream now provides the following families of
functions for performing handshakes:
When operating in the server role:
* stream::accept
* stream::accept_ex
* stream::async_accept
* stream::async_accept_ex
When operating in the client role:
* stream::handshake
* stream::handshake_ex
* stream::async_handshake
* stream::async_handshake_ex
Member functions ending with "_ex" allow an additional
RequestDecorator parameter (for the accept family of
functions) or ResponseDecorator parameter (for the
handshake family of functions).
The decorator is called to optionally modify the contents
of the HTTP request or HTTP response object generated by
the implementation, before the message is sent. This
permits callers to set the User-Agent or Server fields,
add or modify HTTP fields related to subprotocols, or
perform any required transformation of the HTTP message
for application-specific needs.
The handshake() family of functions now have an additional
set of overloads accepting a parameter of type response_type&,
allowing the caller to receive the HTTP Response to the
Upgrade handshake. This permits inspection of the response
to handle things like subprotocols, authentication, or
other application-specific needs.
The new implementation does not require any state to be
stored in the stream object. Therefore, websocket::stream
objects are now smaller in size.
The overload of set_option for setting a decorator on the
stream is removed. The only way to set decorators now is
with a suitable overload of accept or handshake.
This adds enough functions to the accept and async_accept
overload set to cover all combinations of request, buffers,
and error_code parameters. This also fixes a defect where
providing a complete Upgrade request when there are additional
unprocessed octets remaining in the callers stream buffer
could not be furnished to the WebSocket implementation.
fix#123fix#154fix#265
This completely replaces the HTTP parser used to read and
parse incoming messages. The new version is faster than
the old one, and written in fewer lines. A summary of
changes:
* parse and async_parse renamed to read and async_read
* basic_parser is optimized for linear buffers,
use flat_streambuf for the best performance with these
functions:
- http::read
- http::read_some
- http::async_read
- http::async_read_some
* The overloads of read() and async_read() which take
just a header have been removed, since they would
throw away important parse metadata.
* The derived class callbacks for basic_parser have
been streamlined. All strings passed to callbacks
are presented in their entirety, instead of being
provided in pieces.
These changes allow use-cases that were previously
difficult or impossible, such as:
- Efficient relaying
- Late body type commitment
- Expect: 100-continue handling
Objects of this type meet the requirements of DynamicBuffer
and offer an additional invariant: buffer sequences returned
by data() and prepare() are always of length one.
Vinnie Falco