Files
xahaud/examples/http_stream.ipp
Vinnie Falco 8b62c23ab6 Beast.HTTP:
New classes are introduced to represent HTTP messages and their
associated bodies. The parser interface is reworked to use CRTP,
error codes, and trait checks.

New classes:

* basic_headers

  Models field/value pairs in a HTTP message.

* message

  Models a HTTP message, body behavior defined by template argument.
  Parsed message carries metadata generated during parsing.

* parser

  Produces parsed messages.

* empty_body, string_body, basic_streambuf_body

  Classes used to represent content bodies in various ways.

New functions:

* read, async_read, write, async_write

  Read and write HTTP messages on a socket.

New concepts:

* Body: Represents the HTTP Content-Body.
* Field: A HTTP header field.
* FieldSequence: A forward sequence of fields.
* Reader: Parses a Body from a stream of bytes.
* Writer: Serializes a Body to buffers.

basic_parser changes:

* add write methods which throw exceptions instead
* error_code passed via parameter instead of return value
* fold private member calls into existing callbacks
* basic_parser uses CRTP instead of virtual members
* add documentation on Derived requirements for CRTP

impl/http-parser changes:

* joyent renamed to nodejs to reflect upstream changes
2016-04-20 12:01:15 -04:00

420 lines
11 KiB
C++

//------------------------------------------------------------------------------
/*
This file is part of Beast: https://github.com/vinniefalco/Beast
Copyright 2013, Vinnie Falco <vinnie.falco@gmail.com>
Permission to use, copy, modify, and/or distribute this software for any
purpose with or without fee is hereby granted, provided that the above
copyright notice and this permission notice appear in all copies.
THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
ANY SPECIAL , DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*/
//==============================================================================
#ifndef BEAST_HTTP_STREAM_IPP_INCLUDED
#define BEAST_HTTP_STREAM_IPP_INCLUDED
#include <beast/asio/async_completion.h>
#include <beast/asio/bind_handler.h>
#include <beast/asio/handler_alloc.h>
#include <beast/http/read.h>
#include <beast/http/type_check.h>
#include <beast/http/write.h>
#include <cassert>
namespace beast {
namespace http {
template<class NextLayer, class Allocator>
template<bool isRequest, class Body, class Headers,
class Handler>
class stream<NextLayer, Allocator>::read_op
{
using alloc_type =
handler_alloc<char, Handler>;
struct data
{
stream<NextLayer>& s;
message<isRequest, Body, Headers>& m;
Handler h;
bool cont;
int state = 0;
template<class DeducedHandler>
data(DeducedHandler&& h_, stream<NextLayer>& s_,
message<isRequest, Body, Headers>& m_)
: s(s_)
, m(m_)
, h(std::forward<DeducedHandler>(h_))
, cont(boost_asio_handler_cont_helpers::
is_continuation(h))
{
}
};
std::shared_ptr<data> d_;
public:
read_op(read_op&&) = default;
read_op(read_op const&) = default;
template<class DeducedHandler, class... Args>
read_op(DeducedHandler&& h,
stream<NextLayer>& s, Args&&... args)
: d_(std::allocate_shared<data>(alloc_type{h},
std::forward<DeducedHandler>(h), s,
std::forward<Args>(args)...))
{
(*this)(error_code{}, false);
}
void operator()(error_code const& ec, bool again = true);
friend
auto asio_handler_allocate(
std::size_t size, read_op* op)
{
return boost_asio_handler_alloc_helpers::
allocate(size, op->d_->h);
}
friend
auto asio_handler_deallocate(
void* p, std::size_t size, read_op* op)
{
return boost_asio_handler_alloc_helpers::
deallocate(p, size, op->d_->h);
}
friend
auto asio_handler_is_continuation(read_op* op)
{
return op->d_->cont;
}
template <class Function>
friend
auto asio_handler_invoke(Function&& f, read_op* op)
{
return boost_asio_handler_invoke_helpers::
invoke(f, op->d_->h);
}
};
template<class NextLayer, class Allocator>
template<bool isRequest, class Body, class Headers, class Handler>
void
stream<NextLayer, Allocator>::
read_op<isRequest, Body, Headers, Handler>::
operator()(error_code const& ec, bool again)
{
auto& d = *d_;
d.cont = d.cont || again;
while(! ec && d.state != 99)
{
switch(d.state)
{
case 0:
d.state = 99;
beast::http::async_read(d.s.next_layer_,
d.s.rd_buf_, d.m, std::move(*this));
return;
}
}
d.h(ec);
}
//------------------------------------------------------------------------------
template<class NextLayer, class Allocator>
template<bool isRequest, class Body, class Headers,
class Handler>
class stream<NextLayer, Allocator>::write_op : public op
{
using alloc_type =
handler_alloc<char, Handler>;
struct data
{
stream<NextLayer>& s;
message<isRequest, Body, Headers> m;
Handler h;
bool cont;
int state = 0;
template<class DeducedHandler>
data(DeducedHandler&& h_, stream<NextLayer>& s_,
message<isRequest, Body, Headers> const& m_,
bool cont_)
: s(s_)
, m(m_)
, h(std::forward<DeducedHandler>(h_))
, cont(cont_)
{
}
template<class DeducedHandler>
data(DeducedHandler&& h_, stream<NextLayer>& s_,
message<isRequest, Body, Headers>&& m_,
bool cont_)
: s(s_)
, m(std::move(m_))
, h(std::forward<DeducedHandler>(h_))
, cont(cont_)
{
}
};
std::shared_ptr<data> d_;
public:
write_op(write_op&&) = default;
write_op(write_op const&) = default;
template<class DeducedHandler, class... Args>
write_op(DeducedHandler&& h,
stream<NextLayer>& s, Args&&... args)
: d_(std::allocate_shared<data>(alloc_type{h},
std::forward<DeducedHandler>(h), s,
std::forward<Args>(args)...))
{
}
void
operator()() override
{
(*this)(error_code{}, false);
}
void cancel() override;
void operator()(error_code const& ec, bool again = true);
friend
auto asio_handler_allocate(
std::size_t size, write_op* op)
{
return boost_asio_handler_alloc_helpers::
allocate(size, op->d_->h);
}
friend
auto asio_handler_deallocate(
void* p, std::size_t size, write_op* op)
{
return boost_asio_handler_alloc_helpers::
deallocate(p, size, op->d_->h);
}
friend
auto asio_handler_is_continuation(write_op* op)
{
return op->d_->cont;
}
template <class Function>
friend
auto asio_handler_invoke(Function&& f, write_op* op)
{
return boost_asio_handler_invoke_helpers::
invoke(f, op->d_->h);
}
};
template<class NextLayer, class Allocator>
template<bool isRequest, class Body, class Headers, class Handler>
void
stream<NextLayer, Allocator>::
write_op<isRequest, Body, Headers, Handler>::
cancel()
{
auto& d = *d_;
d.s.get_io_service().post(
bind_handler(std::move(*this),
boost::asio::error::operation_aborted));
}
template<class NextLayer, class Allocator>
template<bool isRequest, class Body, class Headers, class Handler>
void
stream<NextLayer, Allocator>::
write_op<isRequest, Body, Headers, Handler>::
operator()(error_code const& ec, bool again)
{
auto& d = *d_;
d.cont = d.cont || again;
while(! ec && d.state != 99)
{
switch(d.state)
{
case 0:
d.state = 99;
beast::http::async_write(d.s.next_layer_,
d.m, std::move(*this));
return;
}
}
d.h(ec);
if(! d.s.wr_q_.empty())
{
auto& op = d.s.wr_q_.front();
op();
// VFALCO Use allocator
delete &op;
d.s.wr_q_.pop_front();
}
else
{
d.s.wr_active_ = false;
}
}
//------------------------------------------------------------------------------
template<class NextLayer, class Allocator>
stream<NextLayer, Allocator>::
~stream()
{
// Can't destroy with pending operations!
assert(wr_q_.empty());
}
template<class NextLayer, class Allocator>
template<class... Args>
stream<NextLayer, Allocator>::
stream(Args&&... args)
: next_layer_(std::forward<Args>(args)...)
{
}
template<class NextLayer, class Allocator>
void
stream<NextLayer, Allocator>::
cancel(error_code& ec)
{
cancel_all();
lowest_layer().cancel(ec);
}
template<class NextLayer, class Allocator>
template<bool isRequest, class Body, class Headers>
void
stream<NextLayer, Allocator>::
read(message<isRequest, Body, Headers>& msg,
error_code& ec)
{
beast::http::read(next_layer_, rd_buf_, msg, ec);
}
template<class NextLayer, class Allocator>
template<bool isRequest, class Body, class Headers,
class ReadHandler>
auto
stream<NextLayer, Allocator>::
async_read(message<isRequest, Body, Headers>& msg,
ReadHandler&& handler)
{
async_completion<
ReadHandler, void(error_code)
> completion(handler);
read_op<isRequest, Body, Headers,
decltype(completion.handler)>{
completion.handler, *this, msg};
return completion.result.get();
}
template<class NextLayer, class Allocator>
template<bool isRequest, class Body, class Headers>
void
stream<NextLayer, Allocator>::
write(message<isRequest, Body, Headers> const& msg,
error_code& ec)
{
beast::http::write(next_layer_, msg, ec);
}
template<class NextLayer, class Allocator>
template<bool isRequest, class Body, class Headers,
class WriteHandler>
auto
stream<NextLayer, Allocator>::
async_write(message<isRequest, Body, Headers> const& msg,
WriteHandler&& handler)
{
async_completion<
WriteHandler, void(error_code)> completion(handler);
auto const cont = wr_active_ ||
boost_asio_handler_cont_helpers::is_continuation(handler);
if(! wr_active_)
{
wr_active_ = true;
write_op<isRequest, Body, Headers,
decltype(completion.handler)>{
completion.handler, *this, msg, cont }();
}
else
{
// VFALCO Use allocator
wr_q_.push_back(*new write_op<isRequest, Body, Headers,
decltype(completion.handler)>(
completion.handler, *this, msg, cont));
}
return completion.result.get();
}
template<class NextLayer, class Allocator>
template<bool isRequest, class Body, class Headers,
class WriteHandler>
auto
stream<NextLayer, Allocator>::
async_write(message<isRequest, Body, Headers>&& msg,
WriteHandler&& handler)
{
async_completion<
WriteHandler, void(error_code)> completion(handler);
auto const cont = wr_active_ ||
boost_asio_handler_cont_helpers::is_continuation(handler);
if(! wr_active_)
{
wr_active_ = true;
write_op<isRequest, Body, Headers,
decltype(completion.handler)>{completion.handler,
*this, std::move(msg), cont}();
}
else
{
// VFALCO Use allocator
wr_q_.push_back(*new write_op<isRequest, Body, Headers,
decltype(completion.handler)>(completion.handler,
*this, std::move(msg), cont));
}
return completion.result.get();
}
template<class NextLayer, class Allocator>
void
stream<NextLayer, Allocator>::
cancel_all()
{
for(auto it = wr_q_.begin(); it != wr_q_.end();)
{
auto& op = *it++;
op.cancel();
// VFALCO Use allocator
delete &op;
}
wr_q_.clear();
}
} // http
} // beast
#endif