ceph/src/boost/libs/beast/example/websocket/client/sync/websocket_client_sync.cpp

   1 //
   2 // Copyright (c) 2016-2019 Vinnie Falco (vinnie dot falco at gmail dot com)
   3 //
   4 // Distributed under the Boost Software License, Version 1.0. (See accompanying
   5 // file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
   6 //
   7 // Official repository: https://github.com/boostorg/beast
   8 //
   9
  10 //------------------------------------------------------------------------------
  11 //
  12 // Example: WebSocket client, synchronous
  13 //
  14 //------------------------------------------------------------------------------
  15
  16 //[example_websocket_client
  17
  18 #include <boost/beast/core.hpp>
  19 #include <boost/beast/websocket.hpp>
  20 #include <boost/asio/connect.hpp>
  21 #include <boost/asio/ip/tcp.hpp>
  22 #include <cstdlib>
  23 #include <iostream>
  24 #include <string>
  25
  26 namespace beast = boost::beast;         // from <boost/beast.hpp>
  27 namespace http = beast::http;           // from <boost/beast/http.hpp>
  28 namespace websocket = beast::websocket; // from <boost/beast/websocket.hpp>
  29 namespace net = boost::asio;            // from <boost/asio.hpp>
  30 using tcp = boost::asio::ip::tcp;       // from <boost/asio/ip/tcp.hpp>
  31
  32 // Sends a WebSocket message and prints the response
  33 int main(int argc, char** argv)
  34 {
  35     try
  36     {
  37         // Check command line arguments.
  38         if(argc != 4)
  39         {
  40             std::cerr <<
  41                 "Usage: websocket-client-sync <host> <port> <text>\n" <<
  42                 "Example:\n" <<
  43                 "    websocket-client-sync echo.websocket.org 80 \"Hello, world!\"\n";
  44             return EXIT_FAILURE;
  45         }
  46         std::string host = argv[1];
  47         auto const  port = argv[2];
  48         auto const  text = argv[3];
  49
  50         // The io_context is required for all I/O
  51         net::io_context ioc;
  52
  53         // These objects perform our I/O
  54         tcp::resolver resolver{ioc};
  55         websocket::stream<tcp::socket> ws{ioc};
  56
  57         // Look up the domain name
  58         auto const results = resolver.resolve(host, port);
  59
  60         // Make the connection on the IP address we get from a lookup
  61         auto ep = net::connect(ws.next_layer(), results);
  62
  63         // Update the host_ string. This will provide the value of the
  64         // Host HTTP header during the WebSocket handshake.
  65         // See https://tools.ietf.org/html/rfc7230#section-5.4
  66         host += ':' + std::to_string(ep.port());
  67
  68         // Set a decorator to change the User-Agent of the handshake
  69         ws.set_option(websocket::stream_base::decorator(
  70             [](websocket::request_type& req)
  71             {
  72                 req.set(http::field::user_agent,
  73                     std::string(BOOST_BEAST_VERSION_STRING) +
  74                         " websocket-client-coro");
  75             }));
  76
  77         // Perform the websocket handshake
  78         ws.handshake(host, "/");
  79
  80         // Send the message
  81         ws.write(net::buffer(std::string(text)));
  82
  83         // This buffer will hold the incoming message
  84         beast::flat_buffer buffer;
  85
  86         // Read a message into our buffer
  87         ws.read(buffer);
  88
  89         // Close the WebSocket connection
  90         ws.close(websocket::close_code::normal);
  91
  92         // If we get here then the connection is closed gracefully
  93
  94         // The make_printable() function helps print a ConstBufferSequence
  95         std::cout << beast::make_printable(buffer.data()) << std::endl;
  96     }
  97     catch(std::exception const& e)
  98     {
  99         std::cerr << "Error: " << e.what() << std::endl;
 100         return EXIT_FAILURE;
 101     }
 102     return EXIT_SUCCESS;
 103 }
 104
 105 //]