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//
// Copyright (c) 2016-2019 Vinnie Falco (vinnie dot falco at gmail dot com)
//
// Distributed under the Boost Software License, Version 1.0. (See accompanying
// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
//
// Official repository: https://github.com/boostorg/beast
//
//------------------------------------------------------------------------------
//
// Example: HTTP client, synchronous
//
//------------------------------------------------------------------------------
//[example_http_client
#include <boost/beast/core.hpp>
#include <boost/beast/http.hpp>
#include <boost/beast/version.hpp>
#include <boost/asio/connect.hpp>
#include <boost/asio/ip/tcp.hpp>
#include <cstdlib>
#include <iostream>
#include <string>
namespace beast = boost::beast; // from <boost/beast.hpp>
namespace http = beast::http; // from <boost/beast/http.hpp>
namespace net = boost::asio; // from <boost/asio.hpp>
using tcp = net::ip::tcp; // from <boost/asio/ip/tcp.hpp>
// Performs an HTTP GET and prints the response
int main(int argc, char** argv)
{
try
{
// Check command line arguments.
if(argc != 4 && argc != 5)
{
std::cerr <<
"Usage: http-client-sync <host> <port> <target> [<HTTP version: 1.0 or 1.1(default)>]\n" <<
"Example:\n" <<
" http-client-sync www.example.com 80 /\n" <<
" http-client-sync www.example.com 80 / 1.0\n";
return EXIT_FAILURE;
}
auto const host = argv[1];
auto const port = argv[2];
auto const target = argv[3];
int version = argc == 5 && !std::strcmp("1.0", argv[4]) ? 10 : 11;
// The io_context is required for all I/O
net::io_context ioc;
// These objects perform our I/O
tcp::resolver resolver(ioc);
beast::tcp_stream stream(ioc);
// Look up the domain name
auto const results = resolver.resolve(host, port);
// Make the connection on the IP address we get from a lookup
stream.connect(results);
// Set up an HTTP GET request message
http::request<http::string_body> req{http::verb::get, target, version};
req.set(http::field::host, host);
req.set(http::field::user_agent, BOOST_BEAST_VERSION_STRING);
// Send the HTTP request to the remote host
http::write(stream, req);
// This buffer is used for reading and must be persisted
beast::flat_buffer buffer;
// Declare a container to hold the response
http::response<http::dynamic_body> res;
// Receive the HTTP response
http::read(stream, buffer, res);
// Write the message to standard out
std::cout << res << std::endl;
// Gracefully close the socket
beast::error_code ec;
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)
throw beast::system_error{ec};
// If we get here then the connection is closed gracefully
}
catch(std::exception const& e)
{
std::cerr << "Error: " << e.what() << std::endl;
return EXIT_FAILURE;
}
return EXIT_SUCCESS;
}
//]
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