RESTinio

sample/websocket_detailed/main.cpp
#include <iostream>
#include <restinio/all.hpp>
#include <restinio/websocket/websocket.hpp>
#include <fmt/format.h>
using namespace std::chrono_literals;
namespace rr = restinio::router;
using router_t = rr::express_router_t<>;
namespace rws = restinio::websocket::basic;
namespace asio_ns = restinio::asio_ns;
using traits_t =
restinio::traits_t<
restinio::asio_timer_manager_t,
restinio::single_threaded_ostream_logger_t,
router_t >;
using http_server_t = restinio::http_server_t< traits_t >;
// Will be defined later, but we have to have that type right now.
class actual_handler_t;
using actual_handler_shptr_t = std::shared_ptr< actual_handler_t >;
// Type of registry with actual handlers.
using ws_registry_t = std::map< std::uint64_t, actual_handler_shptr_t >;
// The definition of the actual websocket handler.
//
// NOTE: this handler is not thread-safe and should be used
// only when RESTinio is run on a single thread!
//
class actual_handler_t final
: public std::enable_shared_from_this< actual_handler_t >
{
private :
// This timer will be used for checking activity of client.
asio_ns::steady_timer m_timer;
// Reference to the registry.
// It is necessary to remove handler from it when close_frame is received.
ws_registry_t & m_registry;
// Will be set manually after successful upgrade.
rws::ws_handle_t m_wsh;
// Timestamp of last activity from a client.
std::chrono::steady_clock::time_point m_last_activity_at;
rws::opcode_t m_continued_frame_opcode;
std::string m_continuation_frame_buffer;
public :
actual_handler_t(
asio_ns::io_context & io_ctx,
ws_registry_t & registry )
: m_timer{ io_ctx }
, m_registry{ registry }
{
std::cout << this << ": actual_handler created!" << std::endl;
}
~actual_handler_t()
{
std::cout << this << ": actual_handler destroyed!" << std::endl;
}
void start( rws::ws_handle_t wsh )
{
m_wsh = std::move(wsh);
activate( *m_wsh );
m_last_activity_at = std::chrono::steady_clock::now();
schedule_next_ping();
}
void on_message( rws::ws_handle_t wsh, rws::message_handle_t m )
{
// Timestamp of last client activity can be updated.
m_last_activity_at = std::chrono::steady_clock::now();
reschedule_timer();
if( m->opcode() == rws::opcode_t::continuation_frame )
{
m_continuation_frame_buffer.append( m->payload() );
if( m->is_final() )
wsh->send_message(
rws::final_frame,
m_continued_frame_opcode,
m_continuation_frame_buffer );
}
else if( m->opcode() == rws::opcode_t::ping_frame )
{
auto pong = *m;
pong.set_opcode( rws::opcode_t::pong_frame );
wsh->send_message( pong );
}
else if( m->opcode() == rws::opcode_t::pong_frame )
{
}
else if( m->opcode() == rws::opcode_t::connection_close_frame )
{
// Have to store ID because it will be invalidated in shutdown().
const auto id = wsh->connection_id();
wsh->send_message( *m );
wsh->shutdown();
// WS-instance and its handler should be removed from registry.
// This will lead to destruction of actual_handler_t instance.
//
// NOTE: the timer will be cancelled automatically in the
// destructor of actual_handler_t.
m_registry.erase( id );
}
else
{
if( m->is_final() )
wsh->send_message( *m );
else
{
m_continued_frame_opcode = m->opcode();
m_continuation_frame_buffer.append( m->payload() );
}
}
}
private :
const std::chrono::steady_clock::duration m_ping_pause{ 5s };
void schedule_next_ping()
{
m_timer.expires_after( m_ping_pause );
m_timer.async_wait( [this]( auto ec ) {
if( ec ) return;
const auto kill_deadline = m_last_activity_at + 2 * m_ping_pause;
const auto now = std::chrono::steady_clock::now();
if( now >= kill_deadline )
{
// It seems that client is dead.
std::cout << this << ": client seems to be dead" << std::endl;
// We can kill the connection.
const auto id = m_wsh->connection_id();
m_wsh->kill();
m_registry.erase( id );
}
else
{
// A new ping message should be sent.
std::cout << this << ": have to send a ping to client" << std::endl;
// Send new ping message.
m_wsh->send_message(
rws::final_frame,
rws::opcode_t::ping_frame,
restinio::writable_item_t{} );
// Restart the timer.
this->schedule_next_ping();
}
} );
}
void reschedule_timer()
{
// Old timer is no more needed.
m_timer.cancel();
// New timer should be scheduled.
schedule_next_ping();
}
};
// This proxy will be used by RESTinio for calling actual_handler.
struct handler_proxy_t
{
actual_handler_t & m_handler;
handler_proxy_t(
actual_handler_t & handler )
: m_handler{ handler }
{}
void operator()( rws::ws_handle_t wsh, rws::message_handle_t m )
{
m_handler.on_message( std::move(wsh), std::move(m) );
}
};
auto server_handler( asio_ns::io_context & io_ctx, ws_registry_t & registry )
{
auto router = std::make_unique< router_t >();
router->http_get(
"/",
[&io_ctx, &registry]( auto req, auto ){
if( restinio::http_connection_header_t::upgrade == req->header().connection() )
{
auto handler = std::make_shared< actual_handler_t >(
io_ctx, registry );
// Create a websocket in inactive state.
// It will be activated manually later, after modification
// of the registry.
auto wsh = rws::upgrade< traits_t >(
*req,
rws::activation_t::delayed,
handler_proxy_t{ *handler } );
// The new websocket should be added to the registry.
// Otherwise the websocket will be automatically destroyed
// on exit out of scope.
registry.emplace( wsh->connection_id(), handler );
// Activate the new websocket.
handler->start( wsh );
return restinio::request_accepted();
}
return restinio::request_rejected();
} );
return router;
}
int main()
{
using namespace std::chrono;
try
{
// We have to use external Asio's io_context because
// we should have a reference to it in actual_handler_t.
asio_ns::io_context io_ctx;
ws_registry_t registry;
restinio::run(
io_ctx,
restinio::on_this_thread<traits_t>()
.address( "localhost" )
.port( 9001 )
.request_handler( server_handler( io_ctx, registry ) )
.read_next_http_message_timelimit( 10s )
.write_http_response_timelimit( 1s )
.handle_request_timeout( 1s )
.cleanup_func( [&]{ registry.clear(); } ) );
}
catch( const std::exception & ex )
{
std::cerr << "Error: " << ex.what() << std::endl;
return 1;
}
return 0;
}
all.hpp
restinio::asio_timer_manager_t
Timer factory implementation using asio timers.
Definition: asio_timer_manager.hpp:31
restinio::http_server_t
Class for http-server.
Definition: http_server.hpp:169
restinio::writable_item_t
Class for storing the buffers used for streaming body (request/response).
Definition: buffers.hpp:496
nonstd::optional_lite::std11::move
T & move(T &t)
Definition: optional.hpp:465
restinio::router
Definition: boost_regex_engine.hpp:17
restinio::websocket::basic
Definition: utf8.hpp:19
restinio::websocket::basic::opcode_t
opcode_t
Definition: message.hpp:37
restinio::websocket::basic::message_handle_t
std::shared_ptr< message_t > message_handle_t
Request handler, that is the type for calling request handlers.
Definition: message.hpp:227
restinio::websocket::basic::final_frame
constexpr final_frame_flag_t final_frame
Definition: message.hpp:135
restinio::websocket::basic::ws_handle_t
std::shared_ptr< ws_t > ws_handle_t
Alias for ws_t handle.
Definition: ws_connection_base.hpp:27
restinio::request_rejected
RESTINIO_NODISCARD constexpr request_handling_status_t request_rejected() noexcept
Definition: common_types.hpp:53
restinio::http_connection_header_t::upgrade
@ upgrade
restinio::single_threaded_ostream_logger_t
ostream_logger_t< null_mutex_t > single_threaded_ostream_logger_t
Definition: ostream_logger.hpp:102
restinio::run
void run(asio_ns::io_context &ioctx, run_on_this_thread_settings_t< Traits > &&settings)
Helper function for running http server until ctrl+c is hit.
Definition: http_server_run.hpp:216
restinio::request_accepted
RESTINIO_NODISCARD constexpr request_handling_status_t request_accepted() noexcept
Definition: common_types.hpp:46
restinio::traits_t
Definition: traits.hpp:147
websocket.hpp