You cannot select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
WebCC/webcc/http_async_client_base.h

129 lines
3.8 KiB
C++

#ifndef WEBCC_HTTP_ASYNC_CLIENT_BASE_H_
#define WEBCC_HTTP_ASYNC_CLIENT_BASE_H_
#include <functional>
#include <memory>
#include <vector>
#include "boost/asio/deadline_timer.hpp"
#include "boost/asio/io_context.hpp"
#include "boost/asio/ip/tcp.hpp"
#include "webcc/globals.h"
#include "webcc/http_request.h"
#include "webcc/http_response.h"
#include "webcc/http_response_parser.h"
namespace webcc {
// Response callback.
typedef std::function<void(HttpResponsePtr, Error, bool)> HttpResponseCallback;
// HTTP client session in asynchronous mode.
// A request will return without waiting for the response, the callback handler
// will be invoked when the response is received or timeout occurs.
// Don't use the same HttpAsyncClient object in multiple threads.
class HttpAsyncClientBase
: public std::enable_shared_from_this<HttpAsyncClientBase> {
public:
// The |buffer_size| is the bytes of the buffer for reading response.
// 0 means default value (e.g., 1024) will be used.
explicit HttpAsyncClientBase(boost::asio::io_context& io_context,
std::size_t buffer_size = 0);
WEBCC_DELETE_COPY_ASSIGN(HttpAsyncClientBase);
// Set the timeout seconds for reading response.
// The |seconds| is only effective when greater than 0.
void SetTimeout(int seconds);
// Asynchronously connect to the server, send the request, read the response,
// and call the |response_callback| when all these finish.
void Request(HttpRequestPtr request, HttpResponseCallback response_callback);
// Called by the user to cancel the request.
void Stop();
protected:
using tcp = boost::asio::ip::tcp;
typedef tcp::resolver::results_type Endpoints;
typedef std::function<void(boost::system::error_code, std::size_t)>
ReadHandler;
typedef std::function<void(boost::system::error_code, tcp::endpoint)>
ConnectHandler;
typedef std::function<void(boost::system::error_code, std::size_t)>
WriteHandler;
// To enable_shared_from_this for both parent and derived.
// See https://stackoverflow.com/q/657155/6825348
template <typename Derived>
std::shared_ptr<Derived> shared_from_base() {
return std::static_pointer_cast<Derived>(shared_from_this());
}
protected:
virtual void Resolve() = 0;
void DoResolve(const std::string& default_port);
void OnResolve(boost::system::error_code ec,
tcp::resolver::results_type results);
void DoConnect(const Endpoints& endpoints);
void OnConnect(boost::system::error_code ec, tcp::endpoint endpoint);
virtual void OnConnected() = 0;
void DoWrite();
void OnWrite(boost::system::error_code ec, std::size_t length);
void DoRead();
void OnRead(boost::system::error_code ec, std::size_t length);
void DoWaitDeadline();
void OnDeadline(boost::system::error_code ec);
// Terminate all the actors to shut down the connection.
void DoStop();
virtual void SocketAsyncConnect(const Endpoints& endpoints,
ConnectHandler&& handler) = 0;
virtual void SocketAsyncWrite(WriteHandler&& handler) = 0;
virtual void SocketAsyncReadSome(ReadHandler&& handler) = 0;
virtual void SocketClose(boost::system::error_code* ec) = 0;
tcp::resolver resolver_;
HttpRequestPtr request_;
std::vector<char> buffer_;
HttpResponsePtr response_;
std::unique_ptr<HttpResponseParser> response_parser_;
HttpResponseCallback response_callback_;
// Timer for the timeout control.
boost::asio::deadline_timer deadline_;
// Maximum seconds to wait before the client cancels the operation.
// Only for receiving response from server.
int timeout_seconds_;
// Request stopped due to timeout or socket error.
bool stopped_;
// If the error was caused by timeout or not.
// Will be passed to the response handler/callback.
bool timed_out_;
};
} // namespace webcc
#endif // WEBCC_HTTP_ASYNC_CLIENT_BASE_H_