libs/beast/example/http/client/methods/http_client_methods.cpp
// // 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 for every method on httpbin // //------------------------------------------------------------------------------ //[example_http_client_methods #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> // perform a get request void do_get(beast::tcp_stream & stream, http::request<http::string_body> & req, beast::flat_buffer buffer, http::response<http::dynamic_body> & res) { req.target("/get"); req.method(beast::http::verb::get); http::write(stream, req); http::read(stream, buffer, res); } // perform a head request void do_head(beast::tcp_stream & stream, http::request<http::string_body> & req, beast::flat_buffer buffer, http::response<http::dynamic_body> & res) { // we reuse the get endpoint req.target("/get"); req.method(beast::http::verb::head); http::write(stream, req); /* the head response will send back a content-length * without a body. The other requests don't set content-length when not * sending a body back. * * the response parser doesn't know that we sent head, * so we need to manually make sure we're only reading the header * otherwise we're waiting forever for data. */ http::response_parser<http::dynamic_body> p; http::read_header(stream, buffer, p); // move the result over res = p.release(); } // perform a patch request void do_patch(beast::tcp_stream & stream, http::request<http::string_body> & req, beast::flat_buffer buffer, http::response<http::dynamic_body> & res) { req.target("/patch"); req.method(beast::http::verb::patch); req.body() = "Some random patch data"; req.prepare_payload(); // set content-length based on the body http::write(stream, req); http::read(stream, buffer, res); } // perform a put request void do_put(beast::tcp_stream & stream, http::request<http::string_body> & req, beast::flat_buffer buffer, http::response<http::dynamic_body> & res) { req.target("/put"); req.method(beast::http::verb::put); req.body() = "Some random put data"; req.prepare_payload(); // set content-length based on the body http::write(stream, req); http::read(stream, buffer, res); } // perform a post request void do_post(beast::tcp_stream & stream, http::request<http::string_body> & req, beast::flat_buffer buffer, http::response<http::dynamic_body> & res) { req.target("/post"); req.method(beast::http::verb::post); req.body() = "Some random post data"; req.prepare_payload(); // set content-length based on the body http::write(stream, req); http::read(stream, buffer, res); } // perform a delete request void do_delete(beast::tcp_stream & stream, http::request<http::string_body> & req, beast::flat_buffer buffer, http::response<http::dynamic_body> & res) { req.target("/delete"); req.method(beast::http::verb::delete_); // NOTE: delete doesn't require a body req.body() = "Some random delete data"; req.prepare_payload(); // set content-length based on the body http::write(stream, req); http::read(stream, buffer, res); } // Performs an HTTP request against httpbin.cpp.al and prints request & response int main(int argc, char** argv) { try { // Check command line arguments. if(argc != 2) { std::cerr << "Usage: http-client-method <method> \n" << "Example:\n" << " http-client-method get\n" << " http-client-method post\n"; return EXIT_FAILURE; } for (char * c = argv[1]; *c != '\0'; c++) *c = static_cast<char>(std::tolower(*c)); beast::string_view method{argv[1]}; // 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("httpbin.cpp.al", "http"); // 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; req.set(http::field::host, "httpbin.cpp.al"); req.set(http::field::user_agent, BOOST_BEAST_VERSION_STRING); // 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; if (method == "get") do_get(stream, req, buffer, res); else if (method == "head") do_head(stream, req, buffer, res); else if (method == "patch") do_patch(stream, req, buffer, res); else if (method == "put") do_put(stream, req, buffer, res); else if (method == "post") do_post(stream, req, buffer, res); else if (method == "delete") do_delete(stream, req, buffer, res); else { std::cerr << "Unknown method: " << method << std::endl; return EXIT_FAILURE; } // Write the message to standard out std::cout << "Request send:\n-----------------------------\n" << req << std::endl; // Write the message to standard out std::cout << "\n\nResponse received:\n-----------------------------\n" << 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; } //]