db-lab1/WebApp/bserv/client.cpp

76 lines
2.9 KiB
C++

#include "pch.h"
#include "bserv/client.hpp"
#include "bserv/logging.hpp"
#include <chrono>
namespace bserv {
// https://www.boost.org/doc/libs/1_75_0/libs/beast/example/http/client/async/http_client_async.cpp
// https://www.boost.org/doc/libs/1_75_0/libs/beast/example/http/client/coro/http_client_coro.cpp
// sends one async request to a remote server
http::response<http::string_body> http_client_send(
asio::io_context& ioc,
asio::yield_context& yield,
const std::string& host,
const std::string& port,
const http::request<http::string_body>& req) {
beast::error_code ec;
tcp::resolver resolver{ ioc };
const auto results = resolver.async_resolve(host, port, yield[ec]);
if (ec) {
throw request_failed_exception{ "http_client_session::resolver resolve: " + ec.message() };
}
beast::tcp_stream stream{ ioc };
// sets a timeout on the operation
stream.expires_after(std::chrono::seconds(EXPIRY_TIME));
// makes the connection on the IP address we get from a lookup
stream.async_connect(results, yield[ec]);
if (ec) {
throw request_failed_exception{ "http_client_session::stream connect: " + ec.message() };
}
// sets a timeout on the operation
stream.expires_after(std::chrono::seconds(EXPIRY_TIME));
// sends the HTTP request to the remote host
http::async_write(stream, req, yield[ec]);
if (ec) {
throw request_failed_exception{ "http_client_session::stream write: " + ec.message() };
}
beast::flat_buffer buffer;
http::response<http::string_body> res;
// receives the HTTP response
http::async_read(stream, buffer, res, yield[ec]);
if (ec) {
throw request_failed_exception{ "http_client_session::stream read: " + ec.message() };
}
// gracefully close the socket
stream.socket().shutdown(tcp::socket::shutdown_both, ec);
// `not_connected` happens sometimes so don't bother reporting it
if (ec && ec != beast::errc::not_connected) {
// reports the error to the log!
fail(ec, "http_client_session::stream::socket shutdown");
// return;
}
// if we get here then the connection is closed gracefully
return res;
}
request_type get_request(
const std::string& host,
const std::string& target,
const http::verb& method,
const boost::json::value& val) {
request_type req;
req.method(method);
req.target(target);
req.set(http::field::host, host);
req.set(http::field::user_agent, NAME);
req.set(http::field::content_type, "application/json");
req.body() = boost::json::serialize(val);
req.prepare_payload();
return req;
}
} // bserv