1
  2/**
  3 * Module dependencies.
  4 */
  5
  6var Transport = require('../transport')
  7  , parser = require('engine.io-parser')
  8  , debug = require('debug')('engine:ws')
  9
 10/**
 11 * Export the constructor.
 12 */
 13
 14module.exports = WebSocket;
 15
 16/**
 17 * WebSocket transport 
 18 *
 19 * @param {http.ServerRequest}
 20 * @api public
 21 */
 22
 23function WebSocket (req) {
 24  Transport.call(this, req);
 25  var self = this;
 26  this.socket = req.websocket;
 27  this.socket.on('message', this.onData.bind(this));
 28  this.socket.once('close', this.onClose.bind(this));
 29  this.socket.on('error', this.onError.bind(this));
 30  this.socket.on('headers', function (headers) {
 31    self.emit('headers', headers);
 32  });
 33  this.writable = true;
 34};
 35
 36/**
 37 * Inherits from Transport.
 38 */
 39
 40WebSocket.prototype.__proto__ = Transport.prototype;
 41
 42/**
 43 * Transport name
 44 *
 45 * @api public
 46 */
 47
 48WebSocket.prototype.name = 'websocket';
 49
 50/**
 51 * Advertise upgrade support.
 52 *
 53 * @api public
 54 */
 55
 56WebSocket.prototype.handlesUpgrades = true;
 57
 58/**
 59 * Advertise framing support.
 60 *
 61 * @api public
 62 */
 63
 64WebSocket.prototype.supportsFraming = true;
 65
 66/**
 67 * Processes the incoming data.
 68 *
 69 * @param {String} encoded packet
 70 * @api private
 71 */
 72
 73WebSocket.prototype.onData = function (data) {
 74  debug('received "%s"', data);
 75  Transport.prototype.onData.call(this, data);
 76};
 77
 78/**
 79 * Writes a packet payload.
 80 *
 81 * @param {Array} packets
 82 * @api private
 83 */
 84
 85WebSocket.prototype.send = function (packets) {
 86  var self = this;
 87  for (var i = 0, l = packets.length; i < l; i++) {
 88    parser.encodePacket(packets[i], this.supportsBinary, function(data) {
 89      debug('writing "%s"', data);
 90      self.writable = false;
 91      self.socket.send(data, function (err){
 92        if (err) return self.onError('write error', err.stack);
 93        self.writable = true;
 94        self.emit('drain');
 95      });
 96    });
 97  }
 98};
 99
100/**
101 * Closes the transport.
102 *
103 * @api private
104 */
105
106WebSocket.prototype.doClose = function (fn) {
107  debug('closing');
108  this.socket.close();
109  fn && fn();
110};