dvv/connection

WebSocket messaging made easy

In browser

  <script src="conn.js"></script>

Starting communication

  // create new connection
  var conn = new Connection(location.href.replace(/^http/, 'ws'));

  // define handlers
  conn.on('open', function() {
      // opened
  });
  conn.on('close', function() {
      // orderly closed
  });

  // low, transport-level handlers
  conn.on('connecting', function() {
      // transport is (re)connecting
  });
  conn.on('connect', function() {
      // transport connected
  });
  conn.on('disconnect', function() {
      // transport disconnected
  });

  // start communication
  conn.open();

Receive message

  // simple challenge-response id negotiation
  conn.on('auth', function(id, aid) {
      // in handlers `this` is current connection
      this.id = this.id || id;
      // `aid` is for acknowledgement id
      // send id back to the caller
      this.ack(aid, null, this.id);
  });

Send message

  // no ack required
  conn.send('foo', arg1, arg2);

  // ack is required. if ack is not called by remote side,
  // after 2000 ms call ack function with `err === new Error('Exired')`
  conn.expire(2000).send('bar', arg, function(err, result) {
      if (err) {
        // no reply within 2000 ms
        // ...
      } else {
        // all's well
        // ...
      }
  });

In server

var WebSocketServer = require('websocket').server;
// upgrade WebSocketConnection prototype
require('connection/websocket');

// web server
var http = ...;
// WebSocket server on top of web server
var ws = new WebSocketServer({
    httpServer: http,
    fragmentOutgoingMessages: false,
    keepalive: true
});

// WebSocket connection handler
ws.on('request', function(req) {
    //req.reject(403); return;
    var conn = req.accept(null, req.origin);

    // install default handlers
    conn.connect();

    // install custom handlers
    conn.on('you typed', function(val, aid) {
        conn.ack(aid, val);
    });
});

console.log('Listening to http://*:' + port + '. Use Ctrl+C to stop.');