ws_examples.cpp

#include "client_ws.hpp"
#include "server_ws.hpp"
#include <future>

using namespace std;

using WsServer = SimpleWeb::SocketServer<SimpleWeb::WS>;
using WsClient = SimpleWeb::SocketClient<SimpleWeb::WS>;

int main() {
  // WebSocket (WS)-server at port 8080 using 1 thread
  WsServer server;
  server.config.port = 8080;

  // Example 1: echo WebSocket endpoint
  // Added debug messages for example use of the callbacks
  // Test with the following JavaScript:
  //   var ws=new WebSocket("ws://localhost:8080/echo");
  //   ws.onmessage=function(evt){console.log(evt.data);};
  //   ws.send("test");
  auto &echo = server.endpoint["^/echo/?$"];

  echo.on_message = [](shared_ptr<WsServer::Connection> connection, shared_ptr<WsServer::InMessage> in_message) {
    auto out_message = in_message->string();

    cout << "Server: Message received: \"" << out_message << "\" from " << connection.get() << endl;

    cout << "Server: Sending message \"" << out_message << "\" to " << connection.get() << endl;

    // connection->send is an asynchronous function
    connection->send(out_message, [](const SimpleWeb::error_code &ec) {
      if(ec) {
        cout << "Server: Error sending message. " <<
            // See http://www.boost.org/doc/libs/1_55_0/doc/html/boost_asio/reference.html, Error Codes for error code meanings
            "Error: " << ec << ", error message: " << ec.message() << endl;
      }
    });

    // Alternatively use streams:
    // auto out_message = make_shared<WsServer::OutMessage>();
    // *out_message << in_message->string();
    // connection->send(out_message);
  };

  echo.on_open = [](shared_ptr<WsServer::Connection> connection) {
    cout << "Server: Opened connection " << connection.get() << endl;
  };

  // See RFC 6455 7.4.1. for status codes
  echo.on_close = [](shared_ptr<WsServer::Connection> connection, int status, const string & /*reason*/) {
    cout << "Server: Closed connection " << connection.get() << " with status code " << status << endl;
  };

  // Can modify handshake response headers here if needed
  echo.on_handshake = [](shared_ptr<WsServer::Connection> /*connection*/, SimpleWeb::CaseInsensitiveMultimap & /*response_header*/) {
    return SimpleWeb::StatusCode::information_switching_protocols; // Upgrade to websocket
  };

  // See http://www.boost.org/doc/libs/1_55_0/doc/html/boost_asio/reference.html, Error Codes for error code meanings
  echo.on_error = [](shared_ptr<WsServer::Connection> connection, const SimpleWeb::error_code &ec) {
    cout << "Server: Error in connection " << connection.get() << ". "
         << "Error: " << ec << ", error message: " << ec.message() << endl;
  };

  // Example 2: Echo thrice
  // Demonstrating queuing of messages by sending a received message three times back to the client.
  // Concurrent send operations are automatically queued by the library.
  // Test with the following JavaScript:
  //   var ws=new WebSocket("ws://localhost:8080/echo_thrice");
  //   ws.onmessage=function(evt){console.log(evt.data);};
  //   ws.send("test");
  auto &echo_thrice = server.endpoint["^/echo_thrice/?$"];
  echo_thrice.on_message = [](shared_ptr<WsServer::Connection> connection, shared_ptr<WsServer::InMessage> in_message) {
    auto out_message = make_shared<string>(in_message->string());

    connection->send(*out_message, [connection, out_message](const SimpleWeb::error_code &ec) {
      if(!ec)
        connection->send(*out_message); // Sent after the first send operation is finished
    });
    connection->send(*out_message); // Most likely queued. Sent after the first send operation is finished.
  };

  // Example 3: Echo to all WebSocket endpoints
  // Sending received messages to all connected clients
  // Test with the following JavaScript on more than one browser windows:
  //   var ws=new WebSocket("ws://localhost:8080/echo_all");
  //   ws.onmessage=function(evt){console.log(evt.data);};
  //   ws.send("test");
  auto &echo_all = server.endpoint["^/echo_all/?$"];
  echo_all.on_message = [&server](shared_ptr<WsServer::Connection> /*connection*/, shared_ptr<WsServer::InMessage> in_message) {
    auto out_message = in_message->string();

    // echo_all.get_connections() can also be used to solely receive connections on this endpoint
    for(auto &a_connection : server.get_connections())
      a_connection->send(out_message);
  };

  // Start server and receive assigned port when server is listening for requests
  promise<unsigned short> server_port;
  thread server_thread([&server, &server_port]() {
    // Start server
    server.start([&server_port](unsigned short port) {
      server_port.set_value(port);
    });
  });
  cout << "Server listening on port " << server_port.get_future().get() << endl << endl;

  // Example 4: Client communication with server
  // Possible output:
  //   Server: Opened connection 0x7fcf21600380
  //   Client: Opened connection
  //   Client: Sending message: "Hello"
  //   Server: Message received: "Hello" from 0x7fcf21600380
  //   Server: Sending message "Hello" to 0x7fcf21600380
  //   Client: Message received: "Hello"
  //   Client: Sending close connection
  //   Server: Closed connection 0x7fcf21600380 with status code 1000
  //   Client: Closed connection with status code 1000
  WsClient client("localhost:8080/echo");
  client.on_message = [](shared_ptr<WsClient::Connection> connection, shared_ptr<WsClient::InMessage> in_message) {
    cout << "Client: Message received: \"" << in_message->string() << "\"" << endl;

    cout << "Client: Sending close connection" << endl;
    connection->send_close(1000);
  };

  client.on_open = [](shared_ptr<WsClient::Connection> connection) {
    cout << "Client: Opened connection" << endl;

    string out_message("Hello");
    cout << "Client: Sending message: \"" << out_message << "\"" << endl;

    connection->send(out_message);
  };

  client.on_close = [](shared_ptr<WsClient::Connection> /*connection*/, int status, const string & /*reason*/) {
    cout << "Client: Closed connection with status code " << status << endl;
  };

  // See http://www.boost.org/doc/libs/1_55_0/doc/html/boost_asio/reference.html, Error Codes for error code meanings
  client.on_error = [](shared_ptr<WsClient::Connection> /*connection*/, const SimpleWeb::error_code &ec) {
    cout << "Client: Error: " << ec << ", error message: " << ec.message() << endl;
  };

  client.start();

  server_thread.join();
}