happn-primus/transformers/engine.io/library.js

Primus is a simple abstraction around real-time frameworks. It allows you to easily switch between different frameworks without any code changes.

(function(f){var g;if(typeof window!=='undefined'){g=window}else if(typeof self!=='undefined'){g=self}g.eio=f()})(function(){var define,module,exports;return (function e(t,n,r){function s(o,u){if(!n[o]){if(!t[o]){var a=typeof require=="function"&&require;if(!u&&a)return a(o,!0);if(i)return i(o,!0);var f=new Error("Cannot find module '"+o+"'");throw f.code="MODULE_NOT_FOUND",f}var l=n[o]={exports:{}};t[o][0].call(l.exports,function(e){var n=t[o][1][e];return s(n?n:e)},l,l.exports,e,t,n,r)}return n[o].exports}var i=typeof require=="function"&&require;for(var o=0;o<r.length;o++)s(r[o]);return s})({1:[function(_dereq_,module,exports){

module.exports = _dereq_('./socket');

/**
 * Exports parser
 *
 * @api public
 *
 */
module.exports.parser = _dereq_('engine.io-parser');

},{"./socket":2,"engine.io-parser":18}],2:[function(_dereq_,module,exports){
(function (global){
/**
 * Module dependencies.
 */

var transports = _dereq_('./transports');
var Emitter = _dereq_('component-emitter');
var debug = _dereq_('debug')('engine.io-client:socket');
var index = _dereq_('indexof');
var parser = _dereq_('engine.io-parser');
var parseuri = _dereq_('parseuri');
var parsejson = _dereq_('parsejson');
var parseqs = _dereq_('parseqs');

/**
 * Module exports.
 */

module.exports = Socket;

/**
 * Noop function.
 *
 * @api private
 */

function noop(){}

/**
 * Socket constructor.
 *
 * @param {String|Object} uri or options
 * @param {Object} options
 * @api public
 */

function Socket(uri, opts){
  if (!(this instanceof Socket)) return new Socket(uri, opts);

  opts = opts || {};

  if (uri && 'object' == typeof uri) {
    opts = uri;
    uri = null;
  }

  if (uri) {
    uri = parseuri(uri);
    opts.hostname = uri.host;
    opts.secure = uri.protocol == 'https' || uri.protocol == 'wss';
    opts.port = uri.port;
    if (uri.query) opts.query = uri.query;
  } else if (opts.host) {
    opts.hostname = parseuri(opts.host).host;
  }

  this.secure = null != opts.secure ? opts.secure :
    (global.location && 'https:' == location.protocol);

  if (opts.hostname && !opts.port) {
    // if no port is specified manually, use the protocol default
    opts.port = this.secure ? '443' : '80';
  }

  this.agent = opts.agent || false;
  this.hostname = opts.hostname ||
    (global.location ? location.hostname : 'localhost');
  this.port = opts.port || (global.location && location.port ?
       location.port :
       (this.secure ? 443 : 80));
  this.query = opts.query || {};
  if ('string' == typeof this.query) this.query = parseqs.decode(this.query);
  this.upgrade = false !== opts.upgrade;
  this.path = (opts.path || '/engine.io').replace(/\/$/, '') + '/';
  this.forceJSONP = !!opts.forceJSONP;
  this.jsonp = false !== opts.jsonp;
  this.forceBase64 = !!opts.forceBase64;
  this.enablesXDR = !!opts.enablesXDR;
  this.timestampParam = opts.timestampParam || 't';
  this.timestampRequests = opts.timestampRequests;
  this.transports = opts.transports || ['polling', 'websocket'];
  this.readyState = '';
  this.writeBuffer = [];
  this.policyPort = opts.policyPort || 843;
  this.rememberUpgrade = opts.rememberUpgrade || false;
  this.binaryType = null;
  this.onlyBinaryUpgrades = opts.onlyBinaryUpgrades;
  this.perMessageDeflate = false !== opts.perMessageDeflate ? (opts.perMessageDeflate || {}) : false;

  if (true === this.perMessageDeflate) this.perMessageDeflate = {};
  if (this.perMessageDeflate && null == this.perMessageDeflate.threshold) {
    this.perMessageDeflate.threshold = 1024;
  }

  // SSL options for Node.js client
  this.pfx = opts.pfx || null;
  this.key = opts.key || null;
  this.passphrase = opts.passphrase || null;
  this.cert = opts.cert || null;
  this.ca = opts.ca || null;
  this.ciphers = opts.ciphers || null;
  this.rejectUnauthorized = opts.rejectUnauthorized === undefined ? true : opts.rejectUnauthorized;

  // other options for Node.js client
  var freeGlobal = typeof global == 'object' && global;
  if (freeGlobal.global === freeGlobal) {
    if (opts.extraHeaders && Object.keys(opts.extraHeaders).length > 0) {
      this.extraHeaders = opts.extraHeaders;
    }
  }

  this.open();
}

Socket.priorWebsocketSuccess = false;

/**
 * Mix in `Emitter`.
 */

Emitter(Socket.prototype);

/**
 * Protocol version.
 *
 * @api public
 */

Socket.protocol = parser.protocol; // this is an int

/**
 * Expose deps for legacy compatibility
 * and standalone browser access.
 */

Socket.Socket = Socket;
Socket.Transport = _dereq_('./transport');
Socket.transports = _dereq_('./transports');
Socket.parser = _dereq_('engine.io-parser');

/**
 * Creates transport of the given type.
 *
 * @param {String} transport name
 * @return {Transport}
 * @api private
 */

Socket.prototype.createTransport = function (name) {
  debug('creating transport "%s"', name);
  var query = clone(this.query);

  // append engine.io protocol identifier
  query.EIO = parser.protocol;

  // transport name
  query.transport = name;

  // session id if we already have one
  if (this.id) query.sid = this.id;

  var transport = new transports[name]({
    agent: this.agent,
    hostname: this.hostname,
    port: this.port,
    secure: this.secure,
    path: this.path,
    query: query,
    forceJSONP: this.forceJSONP,
    jsonp: this.jsonp,
    forceBase64: this.forceBase64,
    enablesXDR: this.enablesXDR,
    timestampRequests: this.timestampRequests,
    timestampParam: this.timestampParam,
    policyPort: this.policyPort,
    socket: this,
    pfx: this.pfx,
    key: this.key,
    passphrase: this.passphrase,
    cert: this.cert,
    ca: this.ca,
    ciphers: this.ciphers,
    rejectUnauthorized: this.rejectUnauthorized,
    perMessageDeflate: this.perMessageDeflate,
    extraHeaders: this.extraHeaders
  });

  return transport;
};

function clone (obj) {
  var o = {};
  for (var i in obj) {
    if (obj.hasOwnProperty(i)) {
      o[i] = obj[i];
    }
  }
  return o;
}

/**
 * Initializes transport to use and starts probe.
 *
 * @api private
 */
Socket.prototype.open = function () {
  var transport;
  if (this.rememberUpgrade && Socket.priorWebsocketSuccess && this.transports.indexOf('websocket') != -1) {
    transport = 'websocket';
  } else if (0 === this.transports.length) {
    // Emit error on next tick so it can be listened to
    var self = this;
    setTimeout(function() {
      self.emit('error', 'No transports available');
    }, 0);
    return;
  } else {
    transport = this.transports[0];
  }
  this.readyState = 'opening';

  // Retry with the next transport if the transport is disabled (jsonp: false)
  try {
    transport = this.createTransport(transport);
  } catch (e) {
    this.transports.shift();
    this.open();
    return;
  }

  transport.open();
  this.setTransport(transport);
};

/**
 * Sets the current transport. Disables the existing one (if any).
 *
 * @api private
 */

Socket.prototype.setTransport = function(transport){
  debug('setting transport %s', transport.name);
  var self = this;

  if (this.transport) {
    debug('clearing existing transport %s', this.transport.name);
    this.transport.removeAllListeners();
  }

  // set up transport
  this.transport = transport;

  // set up transport listeners
  transport
  .on('drain', function(){
    self.onDrain();
  })
  .on('packet', function(packet){
    self.onPacket(packet);
  })
  .on('error', function(e){
    self.onError(e);
  })
  .on('close', function(){
    self.onClose('transport close');
  });
};

/**
 * Probes a transport.
 *
 * @param {String} transport name
 * @api private
 */

Socket.prototype.probe = function (name) {
  debug('probing transport "%s"', name);
  var transport = this.createTransport(name, { probe: 1 })
    , failed = false
    , self = this;

  Socket.priorWebsocketSuccess = false;

  function onTransportOpen(){
    if (self.onlyBinaryUpgrades) {
      var upgradeLosesBinary = !this.supportsBinary && self.transport.supportsBinary;
      failed = failed || upgradeLosesBinary;
    }
    if (failed) return;

    debug('probe transport "%s" opened', name);
    transport.send([{ type: 'ping', data: 'probe' }]);
    transport.once('packet', function (msg) {
      if (failed) return;
      if ('pong' == msg.type && 'probe' == msg.data) {
        debug('probe transport "%s" pong', name);
        self.upgrading = true;
        self.emit('upgrading', transport);
        if (!transport) return;
        Socket.priorWebsocketSuccess = 'websocket' == transport.name;

        debug('pausing current transport "%s"', self.transport.name);
        self.transport.pause(function () {
          if (failed) return;
          if ('closed' == self.readyState) return;
          debug('changing transport and sending upgrade packet');

          cleanup();

          self.setTransport(transport);
          transport.send([{ type: 'upgrade' }]);
          self.emit('upgrade', transport);
          transport = null;
          self.upgrading = false;
          self.flush();
        });
      } else {
        debug('probe transport "%s" failed', name);
        var err = new Error('probe error');
        err.transport = transport.name;
        self.emit('upgradeError', err);
      }
    });
  }

  function freezeTransport() {
    if (failed) return;

    // Any callback called by transport should be ignored since now
    failed = true;

    cleanup();

    transport.close();
    transport = null;
  }

  //Handle any error that happens while probing
  function onerror(err) {
    var error = new Error('probe error: ' + err);
    error.transport = transport.name;

    freezeTransport();

    debug('probe transport "%s" failed because of error: %s', name, err);

    self.emit('upgradeError', error);
  }

  function onTransportClose(){
    onerror("transport closed");
  }

  //When the socket is closed while we're probing
  function onclose(){
    onerror("socket closed");
  }

  //When the socket is upgraded while we're probing
  function onupgrade(to){
    if (transport && to.name != transport.name) {
      debug('"%s" works - aborting "%s"', to.name, transport.name);
      freezeTransport();
    }
  }

  //Remove all listeners on the transport and on self
  function cleanup(){
    transport.removeListener('open', onTransportOpen);
    transport.removeListener('error', onerror);
    transport.removeListener('close', onTransportClose);
    self.removeListener('close', onclose);
    self.removeListener('upgrading', onupgrade);
  }

  transport.once('open', onTransportOpen);
  transport.once('error', onerror);
  transport.once('close', onTransportClose);

  this.once('close', onclose);
  this.once('upgrading', onupgrade);

  transport.open();

};

/**
 * Called when connection is deemed open.
 *
 * @api public
 */

Socket.prototype.onOpen = function () {
  debug('socket open');
  this.readyState = 'open';
  Socket.priorWebsocketSuccess = 'websocket' == this.transport.name;
  this.emit('open');
  this.flush();

  // we check for `readyState` in case an `open`
  // listener already closed the socket
  if ('open' == this.readyState && this.upgrade && this.transport.pause) {
    debug('starting upgrade probes');
    for (var i = 0, l = this.upgrades.length; i < l; i++) {
      this.probe(this.upgrades[i]);
    }
  }
};

/**
 * Handles a packet.
 *
 * @api private
 */

Socket.prototype.onPacket = function (packet) {
  if ('opening' == this.readyState || 'open' == this.readyState) {
    debug('socket receive: type "%s", data "%s"', packet.type, packet.data);

    this.emit('packet', packet);

    // Socket is live - any packet counts
    this.emit('heartbeat');

    switch (packet.type) {
      case 'open':
        this.onHandshake(parsejson(packet.data));
        break;

      case 'pong':
        this.setPing();
        this.emit('pong');
        break;

      case 'error':
        var err = new Error('server error');
        err.code = packet.data;
        this.onError(err);
        break;

      case 'message':
        this.emit('data', packet.data);
        this.emit('message', packet.data);
        break;
    }
  } else {
    debug('packet received with socket readyState "%s"', this.readyState);
  }
};

/**
 * Called upon handshake completion.
 *
 * @param {Object} handshake obj
 * @api private
 */

Socket.prototype.onHandshake = function (data) {
  this.emit('handshake', data);
  this.id = data.sid;
  this.transport.query.sid = data.sid;
  this.upgrades = this.filterUpgrades(data.upgrades);
  this.pingInterval = data.pingInterval;
  this.pingTimeout = data.pingTimeout;
  this.onOpen();
  // In case open handler closes socket
  if  ('closed' == this.readyState) return;
  this.setPing();

  // Prolong liveness of socket on heartbeat
  this.removeListener('heartbeat', this.onHeartbeat);
  this.on('heartbeat', this.onHeartbeat);
};

/**
 * Resets ping timeout.
 *
 * @api private
 */

Socket.prototype.onHeartbeat = function (timeout) {
  clearTimeout(this.pingTimeoutTimer);
  var self = this;
  self.pingTimeoutTimer = setTimeout(function () {
    if ('closed' == self.readyState) return;
    self.onClose('ping timeout');
  }, timeout || (self.pingInterval + self.pingTimeout));
};

/**
 * Pings server every `this.pingInterval` and expects response
 * within `this.pingTimeout` or closes connection.
 *
 * @api private
 */

Socket.prototype.setPing = function () {
  var self = this;
  clearTimeout(self.pingIntervalTimer);
  self.pingIntervalTimer = setTimeout(function () {
    debug('writing ping packet - expecting pong within %sms', self.pingTimeout);
    self.ping();
    self.onHeartbeat(self.pingTimeout);
  }, self.pingInterval);
};

/**
* Sends a ping packet.
*
* @api private
*/

Socket.prototype.ping = function () {
  var self = this;
  this.sendPacket('ping', function(){
    self.emit('ping');
  });
};

/**
 * Called on `drain` event
 *
 * @api private
 */

Socket.prototype.onDrain = function() {
  this.writeBuffer.splice(0, this.prevBufferLen);

  // setting prevBufferLen = 0 is very important
  // for example, when upgrading, upgrade packet is sent over,
  // and a nonzero prevBufferLen could cause problems on `drain`
  this.prevBufferLen = 0;

  if (0 === this.writeBuffer.length) {
    this.emit('drain');
  } else {
    this.flush();
  }
};

/**
 * Flush write buffers.
 *
 * @api private
 */

Socket.prototype.flush = function () {
  if ('closed' != this.readyState && this.transport.writable &&
    !this.upgrading && this.writeBuffer.length) {
    debug('flushing %d packets in socket', this.writeBuffer.length);
    this.transport.send(this.writeBuffer);
    // keep track of current length of writeBuffer
    // splice writeBuffer and callbackBuffer on `drain`
    this.prevBufferLen = this.writeBuffer.length;
    this.emit('flush');
  }
};

/**
 * Sends a message.
 *
 * @param {String} message.
 * @param {Function} callback function.
 * @param {Object} options.
 * @return {Socket} for chaining.
 * @api public
 */

Socket.prototype.write =
Socket.prototype.send = function (msg, options, fn) {
  this.sendPacket('message', msg, options, fn);
  return this;
};

/**
 * Sends a packet.
 *
 * @param {String} packet type.
 * @param {String} data.
 * @param {Object} options.
 * @param {Function} callback function.
 * @api private
 */

Socket.prototype.sendPacket = function (type, data, options, fn) {
  if('function' == typeof data) {
    fn = data;
    data = undefined;
  }

  if ('function' == typeof options) {
    fn = options;
    options = null;
  }

  if ('closing' == this.readyState || 'closed' == this.readyState) {
    return;
  }

  options = options || {};
  options.compress = false !== options.compress;

  var packet = {
    type: type,
    data: data,
    options: options
  };
  this.emit('packetCreate', packet);
  this.writeBuffer.push(packet);
  if (fn) this.once('flush', fn);
  this.flush();
};

/**
 * Closes the connection.
 *
 * @api private
 */

Socket.prototype.close = function () {
  if ('opening' == this.readyState || 'open' == this.readyState) {
    this.readyState = 'closing';

    var self = this;

    if (this.writeBuffer.length) {
      this.once('drain', function() {
        if (this.upgrading) {
          waitForUpgrade();
        } else {
          close();
        }
      });
    } else if (this.upgrading) {
      waitForUpgrade();
    } else {
      close();
    }
  }

  function close() {
    self.onClose('forced close');
    debug('socket closing - telling transport to close');
    self.transport.close();
  }

  function cleanupAndClose() {
    self.removeListener('upgrade', cleanupAndClose);
    self.removeListener('upgradeError', cleanupAndClose);
    close();
  }

  function waitForUpgrade() {
    // wait for upgrade to finish since we can't send packets while pausing a transport
    self.once('upgrade', cleanupAndClose);
    self.once('upgradeError', cleanupAndClose);
  }

  return this;
};

/**
 * Called upon transport error
 *
 * @api private
 */

Socket.prototype.onError = function (err) {
  debug('socket error %j', err);
  Socket.priorWebsocketSuccess = false;
  this.emit('error', err);
  this.onClose('transport error', err);
};

/**
 * Called upon transport close.
 *
 * @api private
 */

Socket.prototype.onClose = function (reason, desc) {
  if ('opening' == this.readyState || 'open' == this.readyState || 'closing' == this.readyState) {
    debug('socket close with reason: "%s"', reason);
    var self = this;

    // clear timers
    clearTimeout(this.pingIntervalTimer);
    clearTimeout(this.pingTimeoutTimer);

    // stop event from firing again for transport
    this.transport.removeAllListeners('close');

    // ensure transport won't stay open
    this.transport.close();

    // ignore further transport communication
    this.transport.removeAllListeners();

    // set ready state
    this.readyState = 'closed';

    // clear session id
    this.id = null;

    // emit close event
    this.emit('close', reason, desc);

    // clean buffers after, so users can still
    // grab the buffers on `close` event
    self.writeBuffer = [];
    self.prevBufferLen = 0;
  }
};

/**
 * Filters upgrades, returning only those matching client transports.
 *
 * @param {Array} server upgrades
 * @api private
 *
 */

Socket.prototype.filterUpgrades = function (upgrades) {
  var filteredUpgrades = [];
  for (var i = 0, j = upgrades.length; i<j; i++) {
    if (~index(this.transports, upgrades[i])) filteredUpgrades.push(upgrades[i]);
  }
  return filteredUpgrades;
};

}).call(this,typeof self !== "undefined" ? self : typeof window !== "undefined" ? window : {})
},{"./transport":3,"./transports":4,"component-emitter":14,"debug":16,"engine.io-parser":18,"indexof":22,"parsejson":25,"parseqs":26,"parseuri":27}],3:[function(_dereq_,module,exports){
/**
 * Module dependencies.
 */

var parser = _dereq_('engine.io-parser');
var Emitter = _dereq_('component-emitter');

/**
 * Module exports.
 */

module.exports = Transport;

/**
 * Transport abstract constructor.
 *
 * @param {Object} options.
 * @api private
 */

function Transport (opts) {
  this.path = opts.path;
  this.hostname = opts.hostname;
  this.port = opts.port;
  this.secure = opts.secure;
  this.query = opts.query;
  this.timestampParam = opts.timestampParam;
  this.timestampRequests = opts.timestampRequests;
  this.readyState = '';
  this.agent = opts.agent || false;
  this.socket = opts.socket;
  this.enablesXDR = opts.enablesXDR;

  // SSL options for Node.js client
  this.pfx = opts.pfx;
  this.key = opts.key;
  this.passphrase = opts.passphrase;
  this.cert = opts.cert;
  this.ca = opts.ca;
  this.ciphers = opts.ciphers;
  this.rejectUnauthorized = opts.rejectUnauthorized;

  // other options for Node.js client
  this.extraHeaders = opts.extraHeaders;
}

/**
 * Mix in `Emitter`.
 */

Emitter(Transport.prototype);

/**
 * Emits an error.
 *
 * @param {String} str
 * @return {Transport} for chaining
 * @api public
 */

Transport.prototype.onError = function (msg, desc) {
  var err = new Error(msg);
  err.type = 'TransportError';
  err.description = desc;
  this.emit('error', err);
  return this;
};

/**
 * Opens the transport.
 *
 * @api public
 */

Transport.prototype.open = function () {
  if ('closed' == this.readyState || '' == this.readyState) {
    this.readyState = 'opening';
    this.doOpen();
  }

  return this;
};

/**
 * Closes the transport.
 *
 * @api private
 */

Transport.prototype.close = function () {
  if ('opening' == this.readyState || 'open' == this.readyState) {
    this.doClose();
    this.onClose();
  }

  return this;
};

/**
 * Sends multiple packets.
 *
 * @param {Array} packets
 * @api private
 */

Transport.prototype.send = function(packets){
  if ('open' == this.readyState) {
    this.write(packets);
  } else {
    throw new Error('Transport not open');
  }
};

/**
 * Called upon open
 *
 * @api private
 */

Transport.prototype.onOpen = function () {
  this.readyState = 'open';
  this.writable = true;
  this.emit('open');
};

/**
 * Called with data.
 *
 * @param {String} data
 * @api private
 */

Transport.prototype.onData = function(data){
  var packet = parser.decodePacket(data, this.socket.binaryType);
  this.onPacket(packet);
};

/**
 * Called with a decoded packet.
 */

Transport.prototype.onPacket = function (packet) {
  this.emit('packet', packet);
};

/**
 * Called upon close.
 *
 * @api private
 */

Transport.prototype.onClose = function () {
  this.readyState = 'closed';
  this.emit('close');
};

},{"component-emitter":14,"engine.io-parser":18}],4:[function(_dereq_,module,exports){
(function (global){
/**
 * Module dependencies
 */

var XMLHttpRequest = _dereq_('xmlhttprequest-ssl');
var XHR = _dereq_('./polling-xhr');
var JSONP = _dereq_('./polling-jsonp');
var websocket = _dereq_('./websocket');

/**
 * Export transports.
 */

exports.polling = polling;
exports.websocket = websocket;

/**
 * Polling transport polymorphic constructor.
 * Decides on xhr vs jsonp based on feature detection.
 *
 * @api private
 */

function polling(opts){
  var xhr;
  var xd = false;
  var xs = false;
  var jsonp = false !== opts.jsonp;

  if (global.location) {
    var isSSL = 'https:' == location.protocol;
    var port = location.port;

    // some user agents have empty `location.port`
    if (!port) {
      port = isSSL ? 443 : 80;
    }

    xd = opts.hostname != location.hostname || port != opts.port;
    xs = opts.secure != isSSL;
  }

  opts.xdomain = xd;
  opts.xscheme = xs;
  xhr = new XMLHttpRequest(opts);

  if ('open' in xhr && !opts.forceJSONP) {
    return new XHR(opts);
  } else {
    if (!jsonp) throw new Error('JSONP disabled');
    return new JSONP(opts);
  }
}

}).call(this,typeof self !== "undefined" ? self : typeof window !== "undefined" ? window : {})
},{"./polling-jsonp":5,"./polling-xhr":6,"./websocket":8,"xmlhttprequest-ssl":9}],5:[function(_dereq_,module,exports){
(function (global){

/**
 * Module requirements.
 */

var Polling = _dereq_('./polling');
var inherit = _dereq_('component-inherit');

/**
 * Module exports.
 */

module.exports = JSONPPolling;

/**
 * Cached regular expressions.
 */

var rNewline = /\n/g;
var rEscapedNewline = /\\n/g;

/**
 * Global JSONP callbacks.
 */

var callbacks;

/**
 * Callbacks count.
 */

var index = 0;

/**
 * Noop.
 */

function empty () { }

/**
 * JSONP Polling constructor.
 *
 * @param {Object} opts.
 * @api public
 */

function JSONPPolling (opts) {
  Polling.call(this, opts);

  this.query = this.query || {};

  // define global callbacks array if not present
  // we do this here (lazily) to avoid unneeded global pollution
  if (!callbacks) {
    // we need to consider multiple engines in the same page
    if (!global.___eio) global.___eio = [];
    callbacks = global.___eio;
  }

  // callback identifier
  this.index = callbacks.length;

  // add callback to jsonp global
  var self = this;
  callbacks.push(function (msg) {
    self.onData(msg);
  });

  // append to query string
  this.query.j = this.index;

  // prevent spurious errors from being emitted when the window is unloaded
  if (global.document && global.addEventListener) {
    global.addEventListener('beforeunload', function () {
      if (self.script) self.script.onerror = empty;
    }, false);
  }
}

/**
 * Inherits from Polling.
 */

inherit(JSONPPolling, Polling);

/*
 * JSONP only supports binary as base64 encoded strings
 */

JSONPPolling.prototype.supportsBinary = false;

/**
 * Closes the socket.
 *
 * @api private
 */

JSONPPolling.prototype.doClose = function () {
  if (this.script) {
    this.script.parentNode.removeChild(this.script);
    this.script = null;
  }

  if (this.form) {
    this.form.parentNode.removeChild(this.form);
    this.form = null;
    this.iframe = null;
  }

  Polling.prototype.doClose.call(this);
};

/**
 * Starts a poll cycle.
 *
 * @api private
 */

JSONPPolling.prototype.doPoll = function () {
  var self = this;
  var script = document.createElement('script');

  if (this.script) {
    this.script.parentNode.removeChild(this.script);
    this.script = null;
  }

  script.async = true;
  script.src = this.uri();
  script.onerror = function(e){
    self.onError('jsonp poll error',e);
  };

  var insertAt = document.getElementsByTagName('script')[0];
  if (insertAt) {
    insertAt.parentNode.insertBefore(script, insertAt);
  }
  else {
    (document.head || document.body).appendChild(script);
  }
  this.script = script;

  var isUAgecko = 'undefined' != typeof navigator && /gecko/i.test(navigator.userAgent);
  
  if (isUAgecko) {
    setTimeout(function () {
      var iframe = document.createElement('iframe');
      document.body.appendChild(iframe);
      document.body.removeChild(iframe);
    }, 100);
  }
};

/**
 * Writes with a hidden iframe.
 *
 * @param {String} data to send
 * @param {Function} called upon flush.
 * @api private
 */

JSONPPolling.prototype.doWrite = function (data, fn) {
  var self = this;

  if (!this.form) {
    var form = document.createElement('form');
    var area = document.createElement('textarea');
    var id = this.iframeId = 'eio_iframe_' + this.index;
    var iframe;

    form.className = 'socketio';
    form.style.position = 'absolute';
    form.style.top = '-1000px';
    form.style.left = '-1000px';
    form.target = id;
    form.method = 'POST';
    form.setAttribute('accept-charset', 'utf-8');
    area.name = 'd';
    form.appendChild(area);
    document.body.appendChild(form);

    this.form = form;
    this.area = area;
  }

  this.form.action = this.uri();

  function complete () {
    initIframe();
    fn();
  }

  function initIframe () {
    if (self.iframe) {
      try {
        self.form.removeChild(self.iframe);
      } catch (e) {
        self.onError('jsonp polling iframe removal error', e);
      }
    }

    try {
      // ie6 dynamic iframes with target="" support (thanks Chris Lambacher)
      var html = '<iframe src="javascript:0" name="'+ self.iframeId +'">';
      iframe = document.createElement(html);
    } catch (e) {
      iframe = document.createElement('iframe');
      iframe.name = self.iframeId;
      iframe.src = 'javascript:0';
    }

    iframe.id = self.iframeId;

    self.form.appendChild(iframe);
    self.iframe = iframe;
  }

  initIframe();

  // escape \n to prevent it from being converted into \r\n by some UAs
  // double escaping is required for escaped new lines because unescaping of new lines can be done safely on server-side
  data = data.replace(rEscapedNewline, '\\\n');
  this.area.value = data.replace(rNewline, '\\n');

  try {
    this.form.submit();
  } catch(e) {}

  if (this.iframe.attachEvent) {
    this.iframe.onreadystatechange = function(){
      if (self.iframe.readyState == 'complete') {
        complete();
      }
    };
  } else {
    this.iframe.onload = complete;
  }
};

}).call(this,typeof self !== "undefined" ? self : typeof window !== "undefined" ? window : {})
},{"./polling":7,"component-inherit":15}],6:[function(_dereq_,module,exports){
(function (global){
/**
 * Module requirements.
 */

var XMLHttpRequest = _dereq_('xmlhttprequest-ssl');
var Polling = _dereq_('./polling');
var Emitter = _dereq_('component-emitter');
var inherit = _dereq_('component-inherit');
var debug = _dereq_('debug')('engine.io-client:polling-xhr');

/**
 * Module exports.
 */

module.exports = XHR;
module.exports.Request = Request;

/**
 * Empty function
 */

function empty(){}

/**
 * XHR Polling constructor.
 *
 * @param {Object} opts
 * @api public
 */

function XHR(opts){
  Polling.call(this, opts);

  if (global.location) {
    var isSSL = 'https:' == location.protocol;
    var port = location.port;

    // some user agents have empty `location.port`
    if (!port) {
      port = isSSL ? 443 : 80;
    }

    this.xd = opts.hostname != global.location.hostname ||
      port != opts.port;
    this.xs = opts.secure != isSSL;
  } else {
    this.extraHeaders = opts.extraHeaders;
  }
}

/**
 * Inherits from Polling.
 */

inherit(XHR, Polling);

/**
 * XHR supports binary
 */

XHR.prototype.supportsBinary = true;

/**
 * Creates a request.
 *
 * @param {String} method
 * @api private
 */

XHR.prototype.request = function(opts){
  opts = opts || {};
  opts.uri = this.uri();
  opts.xd = this.xd;
  opts.xs = this.xs;
  opts.agent = this.agent || false;
  opts.supportsBinary = this.supportsBinary;
  opts.enablesXDR = this.enablesXDR;

  // SSL options for Node.js client
  opts.pfx = this.pfx;
  opts.key = this.key;
  opts.passphrase = this.passphrase;
  opts.cert = this.cert;
  opts.ca = this.ca;
  opts.ciphers = this.ciphers;
  opts.rejectUnauthorized = this.rejectUnauthorized;

  // other options for Node.js client
  opts.extraHeaders = this.extraHeaders;

  return new Request(opts);
};

/**
 * Sends data.
 *
 * @param {String} data to send.
 * @param {Function} called upon flush.
 * @api private
 */

XHR.prototype.doWrite = function(data, fn){
  var isBinary = typeof data !== 'string' && data !== undefined;
  var req = this.request({ method: 'POST', data: data, isBinary: isBinary });
  var self = this;
  req.on('success', fn);
  req.on('error', function(err){
    self.onError('xhr post error', err);
  });
  this.sendXhr = req;
};

/**
 * Starts a poll cycle.
 *
 * @api private
 */

XHR.prototype.doPoll = function(){
  debug('xhr poll');
  var req = this.request();
  var self = this;
  req.on('data', function(data){
    self.onData(data);
  });
  req.on('error', function(err){
    self.onError('xhr poll error', err);
  });
  this.pollXhr = req;
};

/**
 * Request constructor
 *
 * @param {Object} options
 * @api public
 */

function Request(opts){
  this.method = opts.method || 'GET';
  this.uri = opts.uri;
  this.xd = !!opts.xd;
  this.xs = !!opts.xs;
  this.async = false !== opts.async;
  this.data = undefined != opts.data ? opts.data : null;
  this.agent = opts.agent;
  this.isBinary = opts.isBinary;
  this.supportsBinary = opts.supportsBinary;
  this.enablesXDR = opts.enablesXDR;

  // SSL options for Node.js client
  this.pfx = opts.pfx;
  this.key = opts.key;
  this.passphrase = opts.passphrase;
  this.cert = opts.cert;
  this.ca = opts.ca;
  this.ciphers = opts.ciphers;
  this.rejectUnauthorized = opts.rejectUnauthorized;

  // other options for Node.js client
  this.extraHeaders = opts.extraHeaders;

  this.create();
}

/**
 * Mix in `Emitter`.
 */

Emitter(Request.prototype);

/**
 * Creates the XHR object and sends the request.
 *
 * @api private
 */

Request.prototype.create = function(){
  var opts = { agent: this.agent, xdomain: this.xd, xscheme: this.xs, enablesXDR: this.enablesXDR };

  // SSL options for Node.js client
  opts.pfx = this.pfx;
  opts.key = this.key;
  opts.passphrase = this.passphrase;
  opts.cert = this.cert;
  opts.ca = this.ca;
  opts.ciphers = this.ciphers;
  opts.rejectUnauthorized = this.rejectUnauthorized;

  var xhr = this.xhr = new XMLHttpRequest(opts);
  var self = this;

  try {
    debug('xhr open %s: %s', this.method, this.uri);
    xhr.open(this.method, this.uri, this.async);
    try {
      if (this.extraHeaders) {
        xhr.setDisableHeaderCheck(true);
        for (var i in this.extraHeaders) {
          if (this.extraHeaders.hasOwnProperty(i)) {
            xhr.setRequestHeader(i, this.extraHeaders[i]);
          }
        }
      }
    } catch (e) {}
    if (this.supportsBinary) {
      // This has to be done after open because Firefox is stupid
      // http://stackoverflow.com/questions/13216903/get-binary-data-with-xmlhttprequest-in-a-firefox-extension
      xhr.responseType = 'arraybuffer';
    }

    if ('POST' == this.method) {
      try {
        if (this.isBinary) {
          xhr.setRequestHeader('Content-type', 'application/octet-stream');
        } else {
          xhr.setRequestHeader('Content-type', 'text/plain;charset=UTF-8');
        }
      } catch (e) {}
    }

    // ie6 check
    if ('withCredentials' in xhr) {
      xhr.withCredentials = true;
    }

    if (this.hasXDR()) {
      xhr.onload = function(){
        self.onLoad();
      };
      xhr.onerror = function(){
        self.onError(xhr.responseText);
      };
    } else {
      xhr.onreadystatechange = function(){
        if (4 != xhr.readyState) return;
        if (200 == xhr.status || 1223 == xhr.status) {
          self.onLoad();
        } else {
          // make sure the `error` event handler that's user-set
          // does not throw in the same tick and gets caught here
          setTimeout(function(){
            self.onError(xhr.status);
          }, 0);
        }
      };
    }

    debug('xhr data %s', this.data);
    xhr.send(this.data);
  } catch (e) {
    // Need to defer since .create() is called directly fhrom the constructor
    // and thus the 'error' event can only be only bound *after* this exception
    // occurs.  Therefore, also, we cannot throw here at all.
    setTimeout(function() {
      self.onError(e);
    }, 0);
    return;
  }

  if (global.document) {
    this.index = Request.requestsCount++;
    Request.requests[this.index] = this;
  }
};

/**
 * Called upon successful response.
 *
 * @api private
 */

Request.prototype.onSuccess = function(){
  this.emit('success');
  this.cleanup();
};

/**
 * Called if we have data.
 *
 * @api private
 */

Request.prototype.onData = function(data){
  this.emit('data', data);
  this.onSuccess();
};

/**
 * Called upon error.
 *
 * @api private
 */

Request.prototype.onError = function(err){
  this.emit('error', err);
  this.cleanup(true);
};

/**
 * Cleans up house.
 *
 * @api private
 */

Request.prototype.cleanup = function(fromError){
  if ('undefined' == typeof this.xhr || null === this.xhr) {
    return;
  }
  // xmlhttprequest
  if (this.hasXDR()) {
    this.xhr.onload = this.xhr.onerror = empty;
  } else {
    this.xhr.onreadystatechange = empty;
  }

  if (fromError) {
    try {
      this.xhr.abort();
    } catch(e) {}
  }

  if (global.document) {
    delete Request.requests[this.index];
  }

  this.xhr = null;
};

/**
 * Called upon load.
 *
 * @api private
 */

Request.prototype.onLoad = function(){
  var data;
  try {
    var contentType;
    try {
      contentType = this.xhr.getResponseHeader('Content-Type').split(';')[0];
    } catch (e) {}
    if (contentType === 'application/octet-stream') {
      data = this.xhr.response;
    } else {
      if (!this.supportsBinary) {
        data = this.xhr.responseText;
      } else {
        try {
          data = String.fromCharCode.apply(null, new Uint8Array(this.xhr.response));
        } catch (e) {
          var ui8Arr = new Uint8Array(this.xhr.response);
          var dataArray = [];
          for (var idx = 0, length = ui8Arr.length; idx < length; idx++) {
            dataArray.push(ui8Arr[idx]);
          }

          data = String.fromCharCode.apply(null, dataArray);
        }
      }
    }
  } catch (e) {
    this.onError(e);
  }
  if (null != data) {
    this.onData(data);
  }
};

/**
 * Check if it has XDomainRequest.
 *
 * @api private
 */

Request.prototype.hasXDR = function(){
  return 'undefined' !== typeof global.XDomainRequest && !this.xs && this.enablesXDR;
};

/**
 * Aborts the request.
 *
 * @api public
 */

Request.prototype.abort = function(){
  this.cleanup();
};

/**
 * Aborts pending requests when unloading the window. This is needed to prevent
 * memory leaks (e.g. when using IE) and to ensure that no spurious error is
 * emitted.
 */

if (global.document) {
  Request.requestsCount = 0;
  Request.requests = {};
  if (global.attachEvent) {
    global.attachEvent('onunload', unloadHandler);
  } else if (global.addEventListener) {
    global.addEventListener('beforeunload', unloadHandler, false);
  }
}

function unloadHandler() {
  for (var i in Request.requests) {
    if (Request.requests.hasOwnProperty(i)) {
      Request.requests[i].abort();
    }
  }
}

}).call(this,typeof self !== "undefined" ? self : typeof window !== "undefined" ? window : {})
},{"./polling":7,"component-emitter":14,"component-inherit":15,"debug":16,"xmlhttprequest-ssl":9}],7:[function(_dereq_,module,exports){
/**
 * Module dependencies.
 */

var Transport = _dereq_('../transport');
var parseqs = _dereq_('parseqs');
var parser = _dereq_('engine.io-parser');
var inherit = _dereq_('component-inherit');
var yeast = _dereq_('yeast');
var debug = _dereq_('debug')('engine.io-client:polling');

/**
 * Module exports.
 */

module.exports = Polling;

/**
 * Is XHR2 supported?
 */

var hasXHR2 = (function() {
  var XMLHttpRequest = _dereq_('xmlhttprequest-ssl');
  var xhr = new XMLHttpRequest({ xdomain: false });
  return null != xhr.responseType;
})();

/**
 * Polling interface.
 *
 * @param {Object} opts
 * @api private
 */

function Polling(opts){
  var forceBase64 = (opts && opts.forceBase64);
  if (!hasXHR2 || forceBase64) {
    this.supportsBinary = false;
  }
  Transport.call(this, opts);
}

/**
 * Inherits from Transport.
 */

inherit(Polling, Transport);

/**
 * Transport name.
 */

Polling.prototype.name = 'polling';

/**
 * Opens the socket (triggers polling). We write a PING message to determine
 * when the transport is open.
 *
 * @api private
 */

Polling.prototype.doOpen = function(){
  this.poll();
};

/**
 * Pauses polling.
 *
 * @param {Function} callback upon buffers are flushed and transport is paused
 * @api private
 */

Polling.prototype.pause = function(onPause){
  var pending = 0;
  var self = this;

  this.readyState = 'pausing';

  function pause(){
    debug('paused');
    self.readyState = 'paused';
    onPause();
  }

  if (this.polling || !this.writable) {
    var total = 0;

    if (this.polling) {
      debug('we are currently polling - waiting to pause');
      total++;
      this.once('pollComplete', function(){
        debug('pre-pause polling complete');
        --total || pause();
      });
    }

    if (!this.writable) {
      debug('we are currently writing - waiting to pause');
      total++;
      this.once('drain', function(){
        debug('pre-pause writing complete');
        --total || pause();
      });
    }
  } else {
    pause();
  }
};

/**
 * Starts polling cycle.
 *
 * @api public
 */

Polling.prototype.poll = function(){
  debug('polling');
  this.polling = true;
  this.doPoll();
  this.emit('poll');
};

/**
 * Overloads onData to detect payloads.
 *
 * @api private
 */

Polling.prototype.onData = function(data){
  var self = this;
  debug('polling got data %s', data);
  var callback = function(packet, index, total) {
    // if its the first message we consider the transport open
    if ('opening' == self.readyState) {
      self.onOpen();
    }

    // if its a close packet, we close the ongoing requests
    if ('close' == packet.type) {
      self.onClose();
      return false;
    }

    // otherwise bypass onData and handle the message
    self.onPacket(packet);
  };

  // decode payload
  parser.decodePayload(data, this.socket.binaryType, callback);

  // if an event did not trigger closing
  if ('closed' != this.readyState) {
    // if we got data we're not polling
    this.polling = false;
    this.emit('pollComplete');

    if ('open' == this.readyState) {
      this.poll();
    } else {
      debug('ignoring poll - transport state "%s"', this.readyState);
    }
  }
};

/**
 * For polling, send a close packet.
 *
 * @api private
 */

Polling.prototype.doClose = function(){
  var self = this;

  function close(){
    debug('writing close packet');
    self.write([{ type: 'close' }]);
  }

  if ('open' == this.readyState) {
    debug('transport open - closing');
    close();
  } else {
    // in case we're trying to close while
    // handshaking is in progress (GH-164)
    debug('transport not open - deferring close');
    this.once('open', close);
  }
};

/**
 * Writes a packets payload.
 *
 * @param {Array} data packets
 * @param {Function} drain callback
 * @api private
 */

Polling.prototype.write = function(packets){
  var self = this;
  this.writable = false;
  var callbackfn = function() {
    self.writable = true;
    self.emit('drain');
  };

  var self = this;
  parser.encodePayload(packets, this.supportsBinary, function(data) {
    self.doWrite(data, callbackfn);
  });
};

/**
 * Generates uri for connection.
 *
 * @api private
 */

Polling.prototype.uri = function(){
  var query = this.query || {};
  var schema = this.secure ? 'https' : 'http';
  var port = '';

  // cache busting is forced
  if (false !== this.timestampRequests) {
    query[this.timestampParam] = yeast();
  }

  if (!this.supportsBinary && !query.sid) {
    query.b64 = 1;
  }

  query = parseqs.encode(query);

  // avoid port if default for schema
  if (this.port && (('https' == schema && this.port != 443) ||
     ('http' == schema && this.port != 80))) {
    port = ':' + this.port;
  }

  // prepend ? to query
  if (query.length) {
    query = '?' + query;
  }

  var ipv6 = this.hostname.indexOf(':') !== -1;
  return schema + '://' + (ipv6 ? '[' + this.hostname + ']' : this.hostname) + port + this.path + query;
};

},{"../transport":3,"component-inherit":15,"debug":16,"engine.io-parser":18,"parseqs":26,"xmlhttprequest-ssl":9,"yeast":29}],8:[function(_dereq_,module,exports){
(function (global){
/**
 * Module dependencies.
 */

var Transport = _dereq_('../transport');
var parser = _dereq_('engine.io-parser');
var parseqs = _dereq_('parseqs');
var inherit = _dereq_('component-inherit');
var yeast = _dereq_('yeast');
var debug = _dereq_('debug')('engine.io-client:websocket');
var BrowserWebSocket = global.WebSocket || global.MozWebSocket;

/**
 * Get either the `WebSocket` or `MozWebSocket` globals
 * in the browser or try to resolve WebSocket-compatible
 * interface exposed by `ws` for Node-like environment.
 */

var WebSocket = BrowserWebSocket;
if (!WebSocket && typeof window === 'undefined') {
  try {
    WebSocket = _dereq_('ws');
  } catch (e) { }
}

/**
 * Module exports.
 */

module.exports = WS;

/**
 * WebSocket transport constructor.
 *
 * @api {Object} connection options
 * @api public
 */

function WS(opts){
  var forceBase64 = (opts && opts.forceBase64);
  if (forceBase64) {
    this.supportsBinary = false;
  }
  this.perMessageDeflate = opts.perMessageDeflate;
  Transport.call(this, opts);
}

/**
 * Inherits from Transport.
 */

inherit(WS, Transport);

/**
 * Transport name.
 *
 * @api public
 */

WS.prototype.name = 'websocket';

/*
 * WebSockets support binary
 */

WS.prototype.supportsBinary = true;

/**
 * Opens socket.
 *
 * @api private
 */

WS.prototype.doOpen = function(){
  if (!this.check()) {
    // let probe timeout
    return;
  }

  var self = this;
  var uri = this.uri();
  var protocols = void(0);
  var opts = {
    agent: this.agent,
    perMessageDeflate: this.perMessageDeflate
  };

  // SSL options for Node.js client
  opts.pfx = this.pfx;
  opts.key = this.key;
  opts.passphrase = this.passphrase;
  opts.cert = this.cert;
  opts.ca = this.ca;
  opts.ciphers = this.ciphers;
  opts.rejectUnauthorized = this.rejectUnauthorized;
  if (this.extraHeaders) {
    opts.headers = this.extraHeaders;
  }

  this.ws = BrowserWebSocket ? new WebSocket(uri) : new WebSocket(uri, protocols, opts);

  if (this.ws.binaryType === undefined) {
    this.supportsBinary = false;
  }

  if (this.ws.supports && this.ws.supports.binary) {
    this.supportsBinary = true;
    this.ws.binaryType = 'buffer';
  } else {
    this.ws.binaryType = 'arraybuffer';
  }

  this.addEventListeners();
};

/**
 * Adds event listeners to the socket
 *
 * @api private
 */

WS.prototype.addEventListeners = function(){
  var self = this;

  this.ws.onopen = function(){
    self.onOpen();
  };
  this.ws.onclose = function(){
    self.onClose();
  };
  this.ws.onmessage = function(ev){
    self.onData(ev.data);
  };
  this.ws.onerror = function(e){
    self.onError('websocket error', e);
  };
};

/**
 * Writes data to socket.
 *
 * @param {Array} array of packets.
 * @api private
 */

WS.prototype.write = function(packets){
  var self = this;
  this.writable = false;

  // encodePacket efficient as it uses WS framing
  // no need for encodePayload
  var total = packets.length;
  for (var i = 0, l = total; i < l; i++) {
    (function(packet) {
      parser.encodePacket(packet, self.supportsBinary, function(data) {
        if (!BrowserWebSocket) {
          // always create a new object (GH-437)
          var opts = {};
          if (packet.options) {
            opts.compress = packet.options.compress;
          }

          if (self.perMessageDeflate) {
            var len = 'string' == typeof data ? global.Buffer.byteLength(data) : data.length;
            if (len < self.perMessageDeflate.threshold) {
              opts.compress = false;
            }
          }
        }

        //Sometimes the websocket has already been closed but the browser didn't
        //have a chance of informing us about it yet, in that case send will
        //throw an error
        try {
          if (BrowserWebSocket) {
            // TypeError is thrown when passing the second argument on Safari
            self.ws.send(data);
          } else {
            self.ws.send(data, opts);
          }
        } catch (e){
          debug('websocket closed before onclose event');
        }

        --total || done();
      });
    })(packets[i]);
  }

  function done(){
    self.emit('flush');

    // fake drain
    // defer to next tick to allow Socket to clear writeBuffer
    setTimeout(function(){
      self.writable = true;
      self.emit('drain');
    }, 0);
  }
};

/**
 * Called upon close
 *
 * @api private
 */

WS.prototype.onClose = function(){
  Transport.prototype.onClose.call(this);
};

/**
 * Closes socket.
 *
 * @api private
 */

WS.prototype.doClose = function(){
  if (typeof this.ws !== 'undefined') {
    this.ws.close();
  }
};

/**
 * Generates uri for connection.
 *
 * @api private
 */

WS.prototype.uri = function(){
  var query = this.query || {};
  var schema = this.secure ? 'wss' : 'ws';
  var port = '';

  // avoid port if default for schema
  if (this.port && (('wss' == schema && this.port != 443)
    || ('ws' == schema && this.port != 80))) {
    port = ':' + this.port;
  }

  // append timestamp to URI
  if (this.timestampRequests) {
    query[this.timestampParam] = yeast();
  }

  // communicate binary support capabilities
  if (!this.supportsBinary) {
    query.b64 = 1;
  }

  query = parseqs.encode(query);

  // prepend ? to query
  if (query.length) {
    query = '?' + query;
  }

  var ipv6 = this.hostname.indexOf(':') !== -1;
  return schema + '://' + (ipv6 ? '[' + this.hostname + ']' : this.hostname) + port + this.path + query;
};

/**
 * Feature detection for WebSocket.
 *
 * @return {Boolean} whether this transport is available.
 * @api public
 */

WS.prototype.check = function(){
  return !!WebSocket && !('__initialize' in WebSocket && this.name === WS.prototype.name);
};

}).call(this,typeof self !== "undefined" ? self : typeof window !== "undefined" ? window : {})
},{"../transport":3,"component-inherit":15,"debug":16,"engine.io-parser":18,"parseqs":26,"ws":undefined,"yeast":29}],9:[function(_dereq_,module,exports){
// browser shim for xmlhttprequest module
var hasCORS = _dereq_('has-cors');

module.exports = function(opts) {
  var xdomain = opts.xdomain;

  // scheme must be same when usign XDomainRequest
  // http://blogs.msdn.com/b/ieinternals/archive/2010/05/13/xdomainrequest-restrictions-limitations-and-workarounds.aspx
  var xscheme = opts.xscheme;

  // XDomainRequest has a flow of not sending cookie, therefore it should be disabled as a default.
  // https://github.com/Automattic/engine.io-client/pull/217
  var enablesXDR = opts.enablesXDR;

  // XMLHttpRequest can be disabled on IE
  try {
    if ('undefined' != typeof XMLHttpRequest && (!xdomain || hasCORS)) {
      return new XMLHttpRequest();
    }
  } catch (e) { }

  // Use XDomainRequest for IE8 if enablesXDR is true
  // because loading bar keeps flashing when using jsonp-polling
  // https://github.com/yujiosaka/socke.io-ie8-loading-example
  try {
    if ('undefined' != typeof XDomainRequest && !xscheme && enablesXDR) {
      return new XDomainRequest();
    }
  } catch (e) { }

  if (!xdomain) {
    try {
      return new window[(['Active'].concat('Object').join('X'))]('Microsoft.XMLHTTP');
    } catch(e) { }
  }
}

},{"has-cors":21}],10:[function(_dereq_,module,exports){
module.exports = after

function after(count, callback, err_cb) {
    var bail = false
    err_cb = err_cb || noop
    proxy.count = count

    return (count === 0) ? callback() : proxy

    function proxy(err, result) {
        if (proxy.count <= 0) {
            throw new Error('after called too many times')
        }
        --proxy.count

        // after first error, rest are passed to err_cb
        if (err) {
            bail = true
            callback(err)
            // future error callbacks will go to error handler
            callback = err_cb
        } else if (proxy.count === 0 && !bail) {
            callback(null, result)
        }
    }
}

function noop() {}

},