sockjs-client/dist/sockjs.js

SockJS-client is a browser JavaScript library that provides a WebSocket-like object.

/* sockjs-client v1.5.1 | http://sockjs.org | MIT license */
(function(f){if(typeof exports==="object"&&typeof module!=="undefined"){module.exports=f()}else if(typeof define==="function"&&define.amd){define([],f)}else{var g;if(typeof window!=="undefined"){g=window}else if(typeof global!=="undefined"){g=global}else if(typeof self!=="undefined"){g=self}else{g=this}g.SockJS = f()}})(function(){var define,module,exports;return (function(){function r(e,n,t){function o(i,f){if(!n[i]){if(!e[i]){var c="function"==typeof require&&require;if(!f&&c)return c(i,!0);if(u)return u(i,!0);var a=new Error("Cannot find module '"+i+"'");throw a.code="MODULE_NOT_FOUND",a}var p=n[i]={exports:{}};e[i][0].call(p.exports,function(r){var n=e[i][1][r];return o(n||r)},p,p.exports,r,e,n,t)}return n[i].exports}for(var u="function"==typeof require&&require,i=0;i<t.length;i++)o(t[i]);return o}return r})()({1:[function(require,module,exports){
(function (global){
'use strict';

var transportList = require('./transport-list');

module.exports = require('./main')(transportList);

// TODO can't get rid of this until all servers do
if ('_sockjs_onload' in global) {
  setTimeout(global._sockjs_onload, 1);
}

}).call(this,typeof global !== "undefined" ? global : typeof self !== "undefined" ? self : typeof window !== "undefined" ? window : {})

},{"./main":14,"./transport-list":16}],2:[function(require,module,exports){
'use strict';

var inherits = require('inherits')
  , Event = require('./event')
  ;

function CloseEvent() {
  Event.call(this);
  this.initEvent('close', false, false);
  this.wasClean = false;
  this.code = 0;
  this.reason = '';
}

inherits(CloseEvent, Event);

module.exports = CloseEvent;

},{"./event":4,"inherits":57}],3:[function(require,module,exports){
'use strict';

var inherits = require('inherits')
  , EventTarget = require('./eventtarget')
  ;

function EventEmitter() {
  EventTarget.call(this);
}

inherits(EventEmitter, EventTarget);

EventEmitter.prototype.removeAllListeners = function(type) {
  if (type) {
    delete this._listeners[type];
  } else {
    this._listeners = {};
  }
};

EventEmitter.prototype.once = function(type, listener) {
  var self = this
    , fired = false;

  function g() {
    self.removeListener(type, g);

    if (!fired) {
      fired = true;
      listener.apply(this, arguments);
    }
  }

  this.on(type, g);
};

EventEmitter.prototype.emit = function() {
  var type = arguments[0];
  var listeners = this._listeners[type];
  if (!listeners) {
    return;
  }
  // equivalent of Array.prototype.slice.call(arguments, 1);
  var l = arguments.length;
  var args = new Array(l - 1);
  for (var ai = 1; ai < l; ai++) {
    args[ai - 1] = arguments[ai];
  }
  for (var i = 0; i < listeners.length; i++) {
    listeners[i].apply(this, args);
  }
};

EventEmitter.prototype.on = EventEmitter.prototype.addListener = EventTarget.prototype.addEventListener;
EventEmitter.prototype.removeListener = EventTarget.prototype.removeEventListener;

module.exports.EventEmitter = EventEmitter;

},{"./eventtarget":5,"inherits":57}],4:[function(require,module,exports){
'use strict';

function Event(eventType) {
  this.type = eventType;
}

Event.prototype.initEvent = function(eventType, canBubble, cancelable) {
  this.type = eventType;
  this.bubbles = canBubble;
  this.cancelable = cancelable;
  this.timeStamp = +new Date();
  return this;
};

Event.prototype.stopPropagation = function() {};
Event.prototype.preventDefault = function() {};

Event.CAPTURING_PHASE = 1;
Event.AT_TARGET = 2;
Event.BUBBLING_PHASE = 3;

module.exports = Event;

},{}],5:[function(require,module,exports){
'use strict';

/* Simplified implementation of DOM2 EventTarget.
 *   http://www.w3.org/TR/DOM-Level-2-Events/events.html#Events-EventTarget
 */

function EventTarget() {
  this._listeners = {};
}

EventTarget.prototype.addEventListener = function(eventType, listener) {
  if (!(eventType in this._listeners)) {
    this._listeners[eventType] = [];
  }
  var arr = this._listeners[eventType];
  // #4
  if (arr.indexOf(listener) === -1) {
    // Make a copy so as not to interfere with a current dispatchEvent.
    arr = arr.concat([listener]);
  }
  this._listeners[eventType] = arr;
};

EventTarget.prototype.removeEventListener = function(eventType, listener) {
  var arr = this._listeners[eventType];
  if (!arr) {
    return;
  }
  var idx = arr.indexOf(listener);
  if (idx !== -1) {
    if (arr.length > 1) {
      // Make a copy so as not to interfere with a current dispatchEvent.
      this._listeners[eventType] = arr.slice(0, idx).concat(arr.slice(idx + 1));
    } else {
      delete this._listeners[eventType];
    }
    return;
  }
};

EventTarget.prototype.dispatchEvent = function() {
  var event = arguments[0];
  var t = event.type;
  // equivalent of Array.prototype.slice.call(arguments, 0);
  var args = arguments.length === 1 ? [event] : Array.apply(null, arguments);
  // TODO: This doesn't match the real behavior; per spec, onfoo get
  // their place in line from the /first/ time they're set from
  // non-null. Although WebKit bumps it to the end every time it's
  // set.
  if (this['on' + t]) {
    this['on' + t].apply(this, args);
  }
  if (t in this._listeners) {
    // Grab a reference to the listeners list. removeEventListener may alter the list.
    var listeners = this._listeners[t];
    for (var i = 0; i < listeners.length; i++) {
      listeners[i].apply(this, args);
    }
  }
};

module.exports = EventTarget;

},{}],6:[function(require,module,exports){
'use strict';

var inherits = require('inherits')
  , Event = require('./event')
  ;

function TransportMessageEvent(data) {
  Event.call(this);
  this.initEvent('message', false, false);
  this.data = data;
}

inherits(TransportMessageEvent, Event);

module.exports = TransportMessageEvent;

},{"./event":4,"inherits":57}],7:[function(require,module,exports){
'use strict';

var JSON3 = require('json3')
  , iframeUtils = require('./utils/iframe')
  ;

function FacadeJS(transport) {
  this._transport = transport;
  transport.on('message', this._transportMessage.bind(this));
  transport.on('close', this._transportClose.bind(this));
}

FacadeJS.prototype._transportClose = function(code, reason) {
  iframeUtils.postMessage('c', JSON3.stringify([code, reason]));
};
FacadeJS.prototype._transportMessage = function(frame) {
  iframeUtils.postMessage('t', frame);
};
FacadeJS.prototype._send = function(data) {
  this._transport.send(data);
};
FacadeJS.prototype._close = function() {
  this._transport.close();
  this._transport.removeAllListeners();
};

module.exports = FacadeJS;

},{"./utils/iframe":47,"json3":58}],8:[function(require,module,exports){
(function (process){
'use strict';

var urlUtils = require('./utils/url')
  , eventUtils = require('./utils/event')
  , JSON3 = require('json3')
  , FacadeJS = require('./facade')
  , InfoIframeReceiver = require('./info-iframe-receiver')
  , iframeUtils = require('./utils/iframe')
  , loc = require('./location')
  ;

var debug = function() {};
if (process.env.NODE_ENV !== 'production') {
  debug = require('debug')('sockjs-client:iframe-bootstrap');
}

module.exports = function(SockJS, availableTransports) {
  var transportMap = {};
  availableTransports.forEach(function(at) {
    if (at.facadeTransport) {
      transportMap[at.facadeTransport.transportName] = at.facadeTransport;
    }
  });

  // hard-coded for the info iframe
  // TODO see if we can make this more dynamic
  transportMap[InfoIframeReceiver.transportName] = InfoIframeReceiver;
  var parentOrigin;

  /* eslint-disable camelcase */
  SockJS.bootstrap_iframe = function() {
    /* eslint-enable camelcase */
    var facade;
    iframeUtils.currentWindowId = loc.hash.slice(1);
    var onMessage = function(e) {
      if (e.source !== parent) {
        return;
      }
      if (typeof parentOrigin === 'undefined') {
        parentOrigin = e.origin;
      }
      if (e.origin !== parentOrigin) {
        return;
      }

      var iframeMessage;
      try {
        iframeMessage = JSON3.parse(e.data);
      } catch (ignored) {
        debug('bad json', e.data);
        return;
      }

      if (iframeMessage.windowId !== iframeUtils.currentWindowId) {
        return;
      }
      switch (iframeMessage.type) {
      case 's':
        var p;
        try {
          p = JSON3.parse(iframeMessage.data);
        } catch (ignored) {
          debug('bad json', iframeMessage.data);
          break;
        }
        var version = p[0];
        var transport = p[1];
        var transUrl = p[2];
        var baseUrl = p[3];
        debug(version, transport, transUrl, baseUrl);
        // change this to semver logic
        if (version !== SockJS.version) {
          throw new Error('Incompatible SockJS! Main site uses:' +
                    ' "' + version + '", the iframe:' +
                    ' "' + SockJS.version + '".');
        }

        if (!urlUtils.isOriginEqual(transUrl, loc.href) ||
            !urlUtils.isOriginEqual(baseUrl, loc.href)) {
          throw new Error('Can\'t connect to different domain from within an ' +
                    'iframe. (' + loc.href + ', ' + transUrl + ', ' + baseUrl + ')');
        }
        facade = new FacadeJS(new transportMap[transport](transUrl, baseUrl));
        break;
      case 'm':
        facade._send(iframeMessage.data);
        break;
      case 'c':
        if (facade) {
          facade._close();
        }
        facade = null;
        break;
      }
    };

    eventUtils.attachEvent('message', onMessage);

    // Start
    iframeUtils.postMessage('s');
  };
};

}).call(this,{ env: {} })

},{"./facade":7,"./info-iframe-receiver":10,"./location":13,"./utils/event":46,"./utils/iframe":47,"./utils/url":52,"debug":55,"json3":58}],9:[function(require,module,exports){
(function (process){
'use strict';

var EventEmitter = require('events').EventEmitter
  , inherits = require('inherits')
  , JSON3 = require('json3')
  , objectUtils = require('./utils/object')
  ;

var debug = function() {};
if (process.env.NODE_ENV !== 'production') {
  debug = require('debug')('sockjs-client:info-ajax');
}

function InfoAjax(url, AjaxObject) {
  EventEmitter.call(this);

  var self = this;
  var t0 = +new Date();
  this.xo = new AjaxObject('GET', url);

  this.xo.once('finish', function(status, text) {
    var info, rtt;
    if (status === 200) {
      rtt = (+new Date()) - t0;
      if (text) {
        try {
          info = JSON3.parse(text);
        } catch (e) {
          debug('bad json', text);
        }
      }

      if (!objectUtils.isObject(info)) {
        info = {};
      }
    }
    self.emit('finish', info, rtt);
    self.removeAllListeners();
  });
}

inherits(InfoAjax, EventEmitter);

InfoAjax.prototype.close = function() {
  this.removeAllListeners();
  this.xo.close();
};

module.exports = InfoAjax;

}).call(this,{ env: {} })

},{"./utils/object":49,"debug":55,"events":3,"inherits":57,"json3":58}],10:[function(require,module,exports){
'use strict';

var inherits = require('inherits')
  , EventEmitter = require('events').EventEmitter
  , JSON3 = require('json3')
  , XHRLocalObject = require('./transport/sender/xhr-local')
  , InfoAjax = require('./info-ajax')
  ;

function InfoReceiverIframe(transUrl) {
  var self = this;
  EventEmitter.call(this);

  this.ir = new InfoAjax(transUrl, XHRLocalObject);
  this.ir.once('finish', function(info, rtt) {
    self.ir = null;
    self.emit('message', JSON3.stringify([info, rtt]));
  });
}

inherits(InfoReceiverIframe, EventEmitter);

InfoReceiverIframe.transportName = 'iframe-info-receiver';

InfoReceiverIframe.prototype.close = function() {
  if (this.ir) {
    this.ir.close();
    this.ir = null;
  }
  this.removeAllListeners();
};

module.exports = InfoReceiverIframe;

},{"./info-ajax":9,"./transport/sender/xhr-local":37,"events":3,"inherits":57,"json3":58}],11:[function(require,module,exports){
(function (process,global){
'use strict';

var EventEmitter = require('events').EventEmitter
  , inherits = require('inherits')
  , JSON3 = require('json3')
  , utils = require('./utils/event')
  , IframeTransport = require('./transport/iframe')
  , InfoReceiverIframe = require('./info-iframe-receiver')
  ;

var debug = function() {};
if (process.env.NODE_ENV !== 'production') {
  debug = require('debug')('sockjs-client:info-iframe');
}

function InfoIframe(baseUrl, url) {
  var self = this;
  EventEmitter.call(this);

  var go = function() {
    var ifr = self.ifr = new IframeTransport(InfoReceiverIframe.transportName, url, baseUrl);

    ifr.once('message', function(msg) {
      if (msg) {
        var d;
        try {
          d = JSON3.parse(msg);
        } catch (e) {
          debug('bad json', msg);
          self.emit('finish');
          self.close();
          return;
        }

        var info = d[0], rtt = d[1];
        self.emit('finish', info, rtt);
      }
      self.close();
    });

    ifr.once('close', function() {
      self.emit('finish');
      self.close();
    });
  };

  // TODO this seems the same as the 'needBody' from transports
  if (!global.document.body) {
    utils.attachEvent('load', go);
  } else {
    go();
  }
}

inherits(InfoIframe, EventEmitter);

InfoIframe.enabled = function() {
  return IframeTransport.enabled();
};

InfoIframe.prototype.close = function() {
  if (this.ifr) {
    this.ifr.close();
  }
  this.removeAllListeners();
  this.ifr = null;
};

module.exports = InfoIframe;

}).call(this,{ env: {} },typeof global !== "undefined" ? global : typeof self !== "undefined" ? self : typeof window !== "undefined" ? window : {})

},{"./info-iframe-receiver":10,"./transport/iframe":22,"./utils/event":46,"debug":55,"events":3,"inherits":57,"json3":58}],12:[function(require,module,exports){
(function (process){
'use strict';

var EventEmitter = require('events').EventEmitter
  , inherits = require('inherits')
  , urlUtils = require('./utils/url')
  , XDR = require('./transport/sender/xdr')
  , XHRCors = require('./transport/sender/xhr-cors')
  , XHRLocal = require('./transport/sender/xhr-local')
  , XHRFake = require('./transport/sender/xhr-fake')
  , InfoIframe = require('./info-iframe')
  , InfoAjax = require('./info-ajax')
  ;

var debug = function() {};
if (process.env.NODE_ENV !== 'production') {
  debug = require('debug')('sockjs-client:info-receiver');
}

function InfoReceiver(baseUrl, urlInfo) {
  debug(baseUrl);
  var self = this;
  EventEmitter.call(this);

  setTimeout(function() {
    self.doXhr(baseUrl, urlInfo);
  }, 0);
}

inherits(InfoReceiver, EventEmitter);

// TODO this is currently ignoring the list of available transports and the whitelist

InfoReceiver._getReceiver = function(baseUrl, url, urlInfo) {
  // determine method of CORS support (if needed)
  if (urlInfo.sameOrigin) {
    return new InfoAjax(url, XHRLocal);
  }
  if (XHRCors.enabled) {
    return new InfoAjax(url, XHRCors);
  }
  if (XDR.enabled && urlInfo.sameScheme) {
    return new InfoAjax(url, XDR);
  }
  if (InfoIframe.enabled()) {
    return new InfoIframe(baseUrl, url);
  }
  return new InfoAjax(url, XHRFake);
};

InfoReceiver.prototype.doXhr = function(baseUrl, urlInfo) {
  var self = this
    , url = urlUtils.addPath(baseUrl, '/info')
    ;
  debug('doXhr', url);

  this.xo = InfoReceiver._getReceiver(baseUrl, url, urlInfo);

  this.timeoutRef = setTimeout(function() {
    debug('timeout');
    self._cleanup(false);
    self.emit('finish');
  }, InfoReceiver.timeout);

  this.xo.once('finish', function(info, rtt) {
    debug('finish', info, rtt);
    self._cleanup(true);
    self.emit('finish', info, rtt);
  });
};

InfoReceiver.prototype._cleanup = function(wasClean) {
  debug('_cleanup');
  clearTimeout(this.timeoutRef);
  this.timeoutRef = null;
  if (!wasClean && this.xo) {
    this.xo.close();
  }
  this.xo = null;
};

InfoReceiver.prototype.close = function() {
  debug('close');
  this.removeAllListeners();
  this._cleanup(false);
};

InfoReceiver.timeout = 8000;

module.exports = InfoReceiver;

}).call(this,{ env: {} })

},{"./info-ajax":9,"./info-iframe":11,"./transport/sender/xdr":34,"./transport/sender/xhr-cors":35,"./transport/sender/xhr-fake":36,"./transport/sender/xhr-local":37,"./utils/url":52,"debug":55,"events":3,"inherits":57}],13:[function(require,module,exports){
(function (global){
'use strict';

module.exports = global.location || {
  origin: 'http://localhost:80'
, protocol: 'http:'
, host: 'localhost'
, port: 80
, href: 'http://localhost/'
, hash: ''
};

}).call(this,typeof global !== "undefined" ? global : typeof self !== "undefined" ? self : typeof window !== "undefined" ? window : {})

},{}],14:[function(require,module,exports){
(function (process,global){
'use strict';

require('./shims');

var URL = require('url-parse')
  , inherits = require('inherits')
  , JSON3 = require('json3')
  , random = require('./utils/random')
  , escape = require('./utils/escape')
  , urlUtils = require('./utils/url')
  , eventUtils = require('./utils/event')
  , transport = require('./utils/transport')
  , objectUtils = require('./utils/object')
  , browser = require('./utils/browser')
  , log = require('./utils/log')
  , Event = require('./event/event')
  , EventTarget = require('./event/eventtarget')
  , loc = require('./location')
  , CloseEvent = require('./event/close')
  , TransportMessageEvent = require('./event/trans-message')
  , InfoReceiver = require('./info-receiver')
  ;

var debug = function() {};
if (process.env.NODE_ENV !== 'production') {
  debug = require('debug')('sockjs-client:main');
}

var transports;

// follow constructor steps defined at http://dev.w3.org/html5/websockets/#the-websocket-interface
function SockJS(url, protocols, options) {
  if (!(this instanceof SockJS)) {
    return new SockJS(url, protocols, options);
  }
  if (arguments.length < 1) {
    throw new TypeError("Failed to construct 'SockJS: 1 argument required, but only 0 present");
  }
  EventTarget.call(this);

  this.readyState = SockJS.CONNECTING;
  this.extensions = '';
  this.protocol = '';

  // non-standard extension
  options = options || {};
  if (options.protocols_whitelist) {
    log.warn("'protocols_whitelist' is DEPRECATED. Use 'transports' instead.");
  }
  this._transportsWhitelist = options.transports;
  this._transportOptions = options.transportOptions || {};
  this._timeout = options.timeout || 0;

  var sessionId = options.sessionId || 8;
  if (typeof sessionId === 'function') {
    this._generateSessionId = sessionId;
  } else if (typeof sessionId === 'number') {
    this._generateSessionId = function() {
      return random.string(sessionId);
    };
  } else {
    throw new TypeError('If sessionId is used in the options, it needs to be a number or a function.');
  }

  this._server = options.server || random.numberString(1000);

  // Step 1 of WS spec - parse and validate the url. Issue #8
  var parsedUrl = new URL(url);
  if (!parsedUrl.host || !parsedUrl.protocol) {
    throw new SyntaxError("The URL '" + url + "' is invalid");
  } else if (parsedUrl.hash) {
    throw new SyntaxError('The URL must not contain a fragment');
  } else if (parsedUrl.protocol !== 'http:' && parsedUrl.protocol !== 'https:') {
    throw new SyntaxError("The URL's scheme must be either 'http:' or 'https:'. '" + parsedUrl.protocol + "' is not allowed.");
  }

  var secure = parsedUrl.protocol === 'https:';
  // Step 2 - don't allow secure origin with an insecure protocol
  if (loc.protocol === 'https:' && !secure) {
    // exception is 127.0.0.0/8 and ::1 urls
    if (!urlUtils.isLoopbackAddr(parsedUrl.hostname)) {
      throw new Error('SecurityError: An insecure SockJS connection may not be initiated from a page loaded over HTTPS');
    }
  }

  // Step 3 - check port access - no need here
  // Step 4 - parse protocols argument
  if (!protocols) {
    protocols = [];
  } else if (!Array.isArray(protocols)) {
    protocols = [protocols];
  }

  // Step 5 - check protocols argument
  var sortedProtocols = protocols.sort();
  sortedProtocols.forEach(function(proto, i) {
    if (!proto) {
      throw new SyntaxError("The protocols entry '" + proto + "' is invalid.");
    }
    if (i < (sortedProtocols.length - 1) && proto === sortedProtocols[i + 1]) {
      throw new SyntaxError("The protocols entry '" + proto + "' is duplicated.");
    }
  });

  // Step 6 - convert origin
  var o = urlUtils.getOrigin(loc.href);
  this._origin = o ? o.toLowerCase() : null;

  // remove the trailing slash
  parsedUrl.set('pathname', parsedUrl.pathname.replace(/\/+$/, ''));

  // store the sanitized url
  this.url = parsedUrl.href;
  debug('using url', this.url);

  // Step 7 - start connection in background
  // obtain server info
  // http://sockjs.github.io/sockjs-protocol/sockjs-protocol-0.3.3.html#section-26
  this._urlInfo = {
    nullOrigin: !browser.hasDomain()
  , sameOrigin: urlUtils.isOriginEqual(this.url, loc.href)
  , sameScheme: urlUtils.isSchemeEqual(this.url, loc.href)
  };

  this._ir = new InfoReceiver(this.url, this._urlInfo);
  this._ir.once('finish', this._receiveInfo.bind(this));
}

inherits(SockJS, EventTarget);

function userSetCode(code) {
  return code === 1000 || (code >= 3000 && code <= 4999);
}

SockJS.prototype.close = function(code, reason) {
  // Step 1
  if (code && !userSetCode(code)) {
    throw new Error('InvalidAccessError: Invalid code');
  }
  // Step 2.4 states the max is 123 bytes, but we are just checking length
  if (reason && reason.length > 123) {
    throw new SyntaxError('reason argument has an invalid length');
  }

  // Step 3.1
  if (this.readyState === SockJS.CLOSING || this.readyState === SockJS.CLOSED) {
    return;
  }

  // TODO look at docs to determine how to set this
  var wasClean = true;
  this._close(code || 1000, reason || 'Normal closure', wasClean);
};

SockJS.prototype.send = function(data) {
  // #13 - convert anything non-string to string
  // TODO this currently turns objects into [object Object]
  if (typeof data !== 'string') {
    data = '' + data;
  }
  if (this.readyState === SockJS.CONNECTING) {
    throw new Error('InvalidStateError: The connection has not been established yet');
  }
  if (this.readyState !== SockJS.OPEN) {
    return;
  }
  this._transport.send(escape.quote(data));
};

SockJS.version = require('./version');

SockJS.CONNECTING = 0;
SockJS.OPEN = 1;
SockJS.CLOSING = 2;
SockJS.CLOSED = 3;

SockJS.prototype._receiveInfo = function(info, rtt) {
  debug('_receiveInfo', rtt);
  this._ir = null;
  if (!info) {
    this._close(1002, 'Cannot connect to server');
    return;
  }

  // establish a round-trip timeout (RTO) based on the
  // round-trip time (RTT)
  this._rto = this.countRTO(rtt);
  // allow server to override url used for the actual transport
  this._transUrl = info.base_url ? info.base_url : this.url;
  info = objectUtils.extend(info, this._urlInfo);
  debug('info', info);
  // determine list of desired and supported transports
  var enabledTransports = transports.filterToEnabled(this._transportsWhitelist, info);
  this._transports = enabledTransports.main;
  debug(this._transports.length + ' enabled transports');

  this._connect();
};

SockJS.prototype._connect = function() {
  for (var Transport = this._transports.shift(); Transport; Transport = this._transports.shift()) {
    debug('attempt', Transport.transportName);
    if (Transport.needBody) {
      if (!global.document.body ||
          (typeof global.document.readyState !== 'undefined' &&
            global.document.readyState !== 'complete' &&
            global.document.readyState !== 'interactive')) {
        debug('waiting for body');
        this._transports.unshift(Transport);
        eventUtils.attachEvent('load', this._connect.bind(this));
        return;
      }
    }

    // calculate timeout based on RTO and round trips. Default to 5s
    var timeoutMs = Math.max(this._timeout, (this._rto * Transport.roundTrips) || 5000);
    this._transportTimeoutId = setTimeout(this._transportTimeout.bind(this), timeoutMs);
    debug('using timeout', timeoutMs);

    var transportUrl = urlUtils.addPath(this._transUrl, '/' + this._server + '/' + this._generateSessionId());
    var options = this._transportOptions[Transport.transportName];
    debug('transport url', transportUrl);
    var transportObj = new Transport(transportUrl, this._transUrl, options);
    transportObj.on('message', this._transportMessage.bind(this));
    transportObj.once('close', this._transportClose.bind(this));
    transportObj.transportName = Transport.transportName;
    this._transport = transportObj;

    return;
  }
  this._close(2000, 'All transports failed', false);
};

SockJS.prototype._transportTimeout = function() {
  debug('_transportTimeout');
  if (this.readyState === SockJS.CONNECTING) {
    if (this._transport) {
      this._transport.close();
    }

    this._transportClose(2007, 'Transport timed out');
  }
};

SockJS.prototype._transportMessage = function(msg) {
  debug('_transportMessage', msg);
  var self = this
    , type = msg.slice(0, 1)
    , content = msg.slice(1)
    , payload
    ;

  // first check for messages that don't need a payload
  switch (type) {
    case 'o':
      this._open();
      return;
    case 'h':
      this.dispatchEvent(new Event('heartbeat'));
      debug('heartbeat', this.transport);
      return;
  }

  if (content) {
    try {
      payload = JSON3.parse(content);
    } catch (e) {
      debug('bad json', content);
    }
  }

  if (typeof payload === 'undefined') {
    debug('empty payload', content);
    return;
  }

  switch (type) {
    case 'a':
      if (Array.isArray(payload)) {
        payload.forEach(function(p) {
          debug('message', self.transport, p);
          self.dispatchEvent(new TransportMessageEvent(p));
        });
      }
      break;
    case 'm':
      debug('message', this.transport, payload);
      this.dispatchEvent(new TransportMessageEvent(payload));
      break;
    case 'c':
      if (Array.isArray(payload) && payload.length === 2) {
        this._close(payload[0], payload[1], true);
      }
      break;
  }
};

SockJS.prototype._transportClose = function(code, reason) {
  debug('_transportClose', this.transport, code, reason);
  if (this._transport) {
    this._transport.removeAllListeners();
    this._transport = null;
    this.transport = null;
  }

  if (!userSetCode(code) && code !== 2000 && this.readyState === SockJS.CONNECTING) {
    this._connect();
    return;
  }

  this._close(code, reason);
};

SockJS.prototype._open = function() {
  debug('_open', this._transport && this._transport.transportName, this.readyState);
  if (this.readyState === SockJS.CONNECTING) {
    if (this._transportTimeoutId) {
      clearTimeout(this._transportTimeoutId);
      this._transportTimeoutId = null;
    }
    this.readyState = SockJS.OPEN;
    this.transport = this._transport.transportName;
    this.dispatchEvent(new Event('open'));
    debug('connected', this.transport);
  } else {
    // The server might have been restarted, and lost track of our
    // connection.
    this._close(1006, 'Server lost session');
  }
};

SockJS.prototype._close = function(code, reason, wasClean) {
  debug('_close', this.transport, code, reason, wasClean, this.readyState);
  var forceFail = false;

  if (this._ir) {
    forceFail = true;
    this._ir.close();
    this._ir = null;
  }
  if (this._transport) {
    this._transport.close();
    this._transport = null;
    this.transport = null;
  }

  if (this.readyState === SockJS.CLOSED) {
    throw new Error('InvalidStateError: SockJS has already been closed');
  }

  this.readyState = SockJS.CLOSING;
  setTimeout(function() {
    this.readyState = SockJS.CLOSED;

    if (forceFail) {
      this.dispatchEvent(new Event('error'));
    }

    var e = new CloseEvent('close');
    e.wasClean = wasClean || false;
    e.code = code || 1000;
    e.reason = reason;

    this.dispatchEvent(e);
    this.onmessage = this.onclose = this.onerror = null;
    debug('disconnected');
  }.bind(this), 0);
};

// See: http://www.erg.abdn.ac.uk/~gerrit/dccp/notes/ccid2/rto_estimator/
// and RFC 2988.
SockJS.prototype.countRTO = function(rtt) {
  // In a local environment, when using IE8/9 and the `jsonp-polling`
  // transport the time needed to establish a connection (the time that pass
  // from the opening of the transport to the call of `_dispatchOpen`) is
  // around 200msec (the lower bound used in the article above) and this
  // causes spurious timeouts. For this reason we calculate a value slightly
  // larger than that used in the article.
  if (rtt > 100) {
    return 4 * rtt; // rto > 400msec
  }
  return 300 + rtt; // 300msec < rto <= 400msec
};

module.exports = function(availableTransports) {
  transports = transport(availableTransports);
  require('./iframe-bootstrap')(SockJS, availableTransports);
  return SockJS;
};

}).call(this,{ env: {} },typeof global !== "undefined" ? global : typeof self !== "undefined" ? self : typeof window !== "undefined" ? window : {})

},{"./event/close":2,"./event/event":4,"./event/eventtarget":5,"./event/trans-message":6,"./iframe-bootstrap":8,"./info-receiver":12,"./location":13,"./shims":15,"./utils/browser":44,"./utils/escape":45,"./utils/event":46,"./utils/log":48,"./utils/object":49,"./utils/random":50,"./utils/transport":51,"./utils/url":52,"./version":53,"debug":55,"inherits":57,"json3":58,"url-parse":61}],15:[function(require,module,exports){
/* eslint-disable */
/* jscs: disable */
'use strict';

// pulled specific shims from https://github.com/es-shims/es5-shim

var ArrayPrototype = Array.prototype;
var ObjectPrototype = Object.prototype;
var FunctionPrototype = Function.prototype;
var StringPrototype = String.prototype;
var array_slice = ArrayPrototype.slice;

var _toString = ObjectPrototype.toString;
var isFunction = function (val) {
    return ObjectPrototype.toString.call(val) === '[object Function]';
};
var isArray = function isArray(obj) {
    return _toString.call(obj) === '[object Array]';
};
var isString = function isString(obj) {
    return _toString.call(obj) === '[object String]';
};

var supportsDescriptors = Object.defineProperty && (function () {
    try {
        Object.defineProperty({}, 'x', {});
        return true;
    } catch (e) { /* this is ES3 */
        return false;
    }
}());

// Define configurable, writable and non-enumerable props
// if they don't exist.
var defineProperty;
if (supportsDescriptors) {
    defineProperty = function (object, name, method, forceAssign) {
        if (!forceAssign && (name in object)) { return; }
        Object.defineProperty(object, name, {
            configurable: true,
            enumerable: false,
            writable: true,
            value: method
        });
    };
} else {
    defineProperty = function (object, name, method, forceAssign) {
        if (!forceAssign && (name in object)) { return; }
        object[name] = method;
    };
}
var defineProperties = function (object, map, forceAssign) {
    for (var name in map) {
        if (ObjectPrototype.hasOwnProperty.call(map, name)) {
          defineProperty(object, name, map[name], forceAssign);
        }
    }
};

var toObject = function (o) {
    if (o == null) { // this matches both null and undefined
        throw new TypeError("can't convert " + o + ' to object');
    }
    return Object(o);
};

//
// Util
// ======
//

// ES5 9.4
// http://es5.github.com/#x9.4
// http://jsperf.com/to-integer

function toInteger(num) {
    var n = +num;
    if (n !== n) { // isNaN
        n = 0;
    } else if (n !== 0 && n !== (1 / 0) && n !== -(1 / 0)) {
        n = (n > 0 || -1) * Math.floor(Math.abs(n));
    }
    return n;
}

function ToUint32(x) {
    return x >>> 0;
}

//
// Function
// ========
//

// ES-5 15.3.4.5
// http://es5.github.com/#x15.3.4.5

function Empty() {}

defineProperties(FunctionPrototype, {
    bind: function bind(that) { // .length is 1
        // 1. Let Target be the this value.
        var target = this;
        // 2. If IsCallable(Target) is false, throw a TypeError exception.
        if (!isFunction(target)) {
            throw new TypeError('Function.prototype.bind called on incompatible ' + target);
        }
        // 3. Let A be a new (possibly empty) internal list of all of the
        //   argument values provided after thisArg (arg1, arg2 etc), in order.
        // XXX slicedArgs will stand in for "A" if used
        var args = array_slice.call(arguments, 1); // for normal call
        // 4. Let F be a new native ECMAScript object.
        // 11. Set the [[Prototype]] internal property of F to the standard
        //   built-in Function prototype object as specified in 15.3.3.1.
        // 12. Set the [[Call]] internal property of F as described in
        //   15.3.4.5.1.
        // 13. Set the [[Construct]] internal property of F as described in
        //   15.3.4.5.2.
        // 14. Set the [[HasInstance]] internal property of F as described in
        //   15.3.4.5.3.
        var binder = function () {

            if (this instanceof bound) {
                // 15.3.4.5.2 [[Construct]]
                // When the [[Construct]] internal method of a function object,
                // F that was created using the bind function is called with a
                // list of arguments ExtraArgs, the following steps are taken:
                // 1. Let target be the value of F's [[TargetFunction]]
                //   internal property.
                // 2. If target has no [[Construct]] internal method, a
                //   TypeError exception is thrown.
                // 3. Let boundArgs be the value of F's [[BoundArgs]] internal
                //   property.
                // 4. Let args be a new list containing the same values as the
                //   list boundArgs in the same order followed by the same
                //   values as the list ExtraArgs in the same order.
                // 5. Return the result of calling the [[Construct]] internal
                //   method of target providing args as the arguments.

                var result = target.apply(
                    this,
                    args.concat(array_slice.call(arguments))
                );
                if (Object(result) === result) {
                    return result;
                }
                return this;

            } else {
                // 15.3.4.5.1 [[Call]]
                // When the [[Call]] internal method of a function object, F,
                // which was created using the bind function is called with a
                // this value and a list of arguments ExtraArgs, the following
                // steps are taken:
                // 1. Let boundArgs be the value of F's [[BoundArgs]] internal
                //   property.
                // 2. Let boundThis be the value of F's [[BoundThis]] internal
                //   property.
                // 3. Let target be the value of F's [[TargetFunction]] internal
                //   property.
                // 4. Let args be a new list containing the same values as the
                //   list boundArgs in the same order followed by the same
                //   values as the list ExtraArgs in the same order.
                // 5. Return the result of calling the [[Call]] internal method
                //   of target providing boundThis as the this value and
                //   providing args as the arguments.

                // equiv: target.call(this, ...boundArgs, ...args)
                return target.apply(
                    that,
                    args.concat(array_slice.call(arguments))
                );

            }

        };

        // 15. If the [[Class]] internal property of Target is "Function", then
        //     a. Let L be the length property of Target minus the length of A.
        //     b. Set the length own property of F to either 0 or L, whichever is
        //       larger.
        // 16. Else set the length own property of F to 0.

        var boundLength = Math.max(0, target.length - args.length);

        // 17. Set the attributes of the length own property of F to the values
        //   specified in 15.3.5.1.
        var boundArgs = [];
        for (var i = 0; i < boundLength; i++) {
            boundArgs.push('$' + i);
        }

        // XXX Build a dynamic function with desired amount of arguments is the only
        // way to set the length property of a function.
        // In environments where Content Security Policies enabled (Chrome extensions,
        // for ex.) all use of eval or Function costructor throws an exception.
        // However in all of these environments Function.prototype.bind exists
        // and so this code will never be executed.
        var bound = Function('binder', 'return function (' + boundArgs.join(',') + '){ return binder.apply(this, arguments); }')(binder);

        if (target.prototype) {
            Empty.prototype = target.prototype;
            bound.prototype = new Empty();
            // Clean up dangling references.
            Empty.prototype = null;
        }

        // TODO
        // 18. Set the [[Extensible]] internal property of F to true.

        // TODO
        // 19. Let thrower be the [[ThrowTypeError]] function Object (13.2.3).
        // 20. Call the [[DefineOwnProperty]] internal method of F with
        //   arguments "caller", PropertyDescriptor {[[Get]]: thrower, [[Set]]:
        //   thrower, [[Enumerable]]: false, [[Configurable]]: false}, and
        //   false.
        // 21. Call the [[DefineOwnProperty]] internal method of F with
        //   arguments "arguments", PropertyDescriptor {[[Get]]: thrower,
        //   [[Set]]: thrower, [[Enumerable]]: false, [[Configurable]]: false},
        //   and false.

        // TODO
        // NOTE Function objects created using Function.prototype.bind do not
        // have a prototype property or the [[Code]], [[FormalParameters]], and
        // [[Scope]] internal properties.
        // XXX can't delete prototype in pure-js.

        // 22. Return F.
        return bound;
    }
});

//
// Array
// =====
//

// ES5 15.4.3.2
// http://es5.github.com/#x15.4.3.2
// https://developer.mozilla.org/en/JavaScript/Reference/Global_Objects/Array/isArray
defineProperties(Array, { isArray: isArray });


var boxedString = Object('a');
var splitString = boxedString[0] !== 'a' || !(0 in boxedString);

var properlyBoxesContext = function properlyBoxed(method) {
    // Check node 0.6.21 bug where third parameter is not boxed
    var properlyBoxesNonStrict = true;
    var properlyBoxesStrict = true;
    if (method) {
        method.call('foo', function (_, __, context) {
            if (typeof context !== 'object') { properlyBoxesNonStrict = false; }
        });

        method.call([1], function () {
            'use strict';
            properlyBoxesStrict = typeof this === 'string';
        }, 'x');
    }
    return !!method && properlyBoxesNonStrict && properlyBoxesStrict;
};

defineProperties(ArrayPrototype, {
    forEach: function forEach(fun /*, thisp*/) {
        var object = toObject(this),
            self = splitString && isString(this) ? this.split('') : object,
            thisp = arguments[1],
            i = -1,
            length = self.length >>> 0;

        // If no callback function or if callback is not a callable function
        if (!isFunction(fun)) {
            throw new TypeError(); // TODO message
        }

        while (++i < length) {
            if (i in self) {
                // Invoke the callback function with call, passing arguments:
                // context, property value, property key, thisArg object
                // context
                fun.call(thisp, self[i], i, object);
            }
        }
    }
}, !properlyBoxesContext(ArrayPrototype.forEach));

// ES5 15.4.4.14
// http://es5.github.com/#x15.4.4.14
// https://developer.mozilla.org/en/JavaScript/Reference/Global_Objects/Array/indexOf
var hasFirefox2IndexOfBug = Array.prototype.indexOf && [0, 1].indexOf(1, 2) !== -1;
defineProperties(ArrayPrototype, {
    indexOf: function indexOf(sought /*, fromIndex */ ) {
        var self = splitString && isString(this) ? this.split('') : toObject(this),
            length = self.length >>> 0;

        if (!length) {
            return -1;
        }

        var i = 0;
        if (arguments.length > 1) {
            i = toInteger(arguments[1]);
        }

        // handle negative indices
        i = i >= 0 ? i : Math.max(0, length + i);
        for (; i < length; i++) {
            if (i in self && self[i] === sought) {
                return i;
            }
        }
        return -1;
    }
}, hasFirefox2IndexOfBug);

//
// String
// ======
//

// ES5 15.5.4.14
// http://es5.github.com/#x15.5.4.14

// [bugfix, IE lt 9, firefox 4, Konqueror, Opera, obscure browsers]
// Many browsers do not split properly with regular expressions or they
// do not perform the split correctly under obscure conditions.
// See http://blog.stevenlevithan.com/archives/cross-browser-split
// I've tested in many browsers and this seems to cover the deviant ones:
//    'ab'.split(/(?:ab)*/) should be ["", ""], not [""]
//    '.'.split(/(.?)(.?)/) should be ["", ".", "", ""], not ["", ""]
//    'tesst'.split(/(s)*/) should be ["t", undefined, "e", "s", "t"], not
//       [undefined, "t", undefined, "e", ...]
//    ''.split(/.?/) should be [], not [""]
//    '.'.split(/()()/) should be ["."], not ["", "", "."]

var string_split = StringPrototype.split;
if (
    'ab'.split(/(?:ab)*/).length !== 2 ||
    '.'.split(/(.?)(.?)/).length !== 4 ||
    'tesst'.split(/(s)*/)[1] === 't' ||
    'test'.split(/(?:)/, -1).length !== 4 ||
    ''.split(/.?/).length ||
    '.'.split(/()()/).length > 1
) {
    (function () {
        var compliantExecNpcg = /()??/.exec('')[1] === void 0; // NPCG: nonparticipating capturing group

        StringPrototype.split = function (separator, limit) {
            var string = this;
            if (separator === void 0 && limit === 0) {
                return [];
            }

            // If `separator` is not a regex, use native split
            if (_toString.call(separator) !== '[object RegExp]') {
                return string_split.call(this, separator, limit);
            }

            var output = [],
                flags = (separator.ignoreCase ? 'i' : '') +
                        (separator.multiline  ? 'm' : '') +
                        (separator.extended   ? 'x' : '') + // Proposed for ES6
                        (separator.sticky     ? 'y' : ''), // Firefox 3+
                lastLastIndex = 0,
                // Make `global` and avoid `lastIndex` issues by working with a copy
                separator2, match, lastIndex, lastLength;
            separator = new RegExp(separator.source, flags + 'g');
            string += ''; // Type-convert
            if (!compliantExecNpcg) {
                // Doesn't need flags gy, but they don't hurt
                separator2 = new RegExp('^' + separator.source + '$(?!\\s)', flags);
            }
            /* Values for `limit`, per the spec:
             * If undefined: 4294967295 // Math.pow(2, 32) - 1
             * If 0, Infinity, or NaN: 0
             * If positive number: limit = Math.floor(limit); if (limit > 4294967295) limit -= 4294967296;
             * If negative number: 4294967296 - Math.floor(Math.abs(limit))
             * If other: Type-convert, then use the above rules
             */
            limit = limit === void 0 ?
                -1 >>> 0 : // Math.pow(2, 32) - 1
                ToUint32(limit);
            while (match = separator.exec(string)) {
                // `separator.lastIndex` is not reliable cross-browser
                lastIndex = match.index + match[0].length;
                if (lastIndex > lastLastIndex) {
                    output.push(string.slice(lastLastIndex, match.index));
                    // Fix browsers whose `exec` methods don't consistently return `undefined` for
                    // nonparticipating capturing groups
                    if (!compliantExecNpcg && match.length > 1) {
                        match[0].replace(separator2, function () {
                            for (var i = 1; i < arguments.length - 2; i++) {
                                if (arguments[i] === void 0) {
                                    match[i] = void 0;
                                }
                            }
                        });
                    }
                    if (match.length > 1 && match.index < string.length) {
                        ArrayPrototype.push.apply(output, match.slice(1));
                    }
                    lastLength = match[0].length;
                    lastLastIndex = lastIndex;
                    if (output.length >= limit) {
                        break;
                    }
                }
                if (separator.lastIndex === match.index) {
                    separator.lastIndex++; // Avoid an infinite loop
                }
            }
            if (lastLastIndex === string.length) {
                if (lastLength || !separator.test('')) {
                    output.push('');
                }
            } else {
                output.push(string.slice(lastLastIndex));
            }
            return output.length > limit ? output.slice(0, limit) : output;
        };
    }());

// [bugfix, chrome]
// If separator is undefined, then the result array contains just one String,
// which is the this value (converted to a String). If limit is not undefined,
// then the output array is truncated so that it contains no more than limit
// elements.
// "0".split(undefined, 0) -> []
} else if ('0'.split(void 0, 0).length) {
    StringPrototype.split = function split(separator, limit) {
        if (separator === void 0 && limit === 0) { return []; }
        return string_split.call(this, separator, limit);
    };
}

// ECMA-262, 3rd B.2.3
// Not an ECMAScript standard, although ECMAScript 3rd Edition has a
// non-normative section suggesting uniform semantics and it should be
// normalized across all browsers
// [bugfix, IE lt 9] IE < 9 substr() with negative value not working in IE
var string_substr = StringPrototype.substr;
var hasNegativeSubstrBug = ''.substr && '0b'.substr(-1) !== 'b';
defineProperties(StringPrototype, {
    substr: function substr(start, length) {
        return string_substr.call(
            this,
            start < 0 ? ((start = this.length + start) < 0 ? 0 : start) : start,
            length
        );
    }
}, hasNegativeSubstrBug);

},{}],16:[function(require,module,exports){
'use strict';

module.exports = [
  // streaming transports
  require('./transport/websocket')
, require('./transport/xhr-streaming')
, require('./transport/xdr-streaming')
, require('./transport/eventsource')
, require('./transport/lib/iframe-wrap')(require('./transport/eventsource'))

  // polling transports
, require('./transport/htmlfile')
, require('./transport/lib/iframe-wrap')(require('./transport/htmlfile'))
, require('./transport/xhr-polling')
, require('./transport/xdr-polling')
, require('./transport/lib/iframe-wrap')(require('./transport/xhr-polling'))
, require('./transport/jsonp-polling')
];

},{"./transport/eventsource":20,"./transport/htmlfile":21,"./transport/jsonp-polling":23,"./transport/lib/iframe-wrap":26,"./transport/websocket":38,"./transport/xdr-polling":39,"./transport/xdr-streaming":40,"./transport/xhr-polling":41,"./transport/xhr-streaming":42}],17:[function(require,module,exports){
(function (process,global){
'use strict';

var EventEmitter = require('events').EventEmitter
  , inherits = require('inherits')
  , utils = require('../../utils/event')
  , urlUtils = require('../../utils/url')
  , XHR = global.XMLHttpRequest
  ;

var debug = function() {};
if (process.env.NODE_ENV !== 'production') {
  debug = require('debug')('sockjs-client:browser:xhr');
}

function AbstractXHRObject(method, url, payload, opts) {
  debug(method, url);
  var self = this;
  EventEmitter.call(this);

  setTimeout(function () {
    self._start(method, url, payload, opts);
  }, 0);
}

inherits(AbstractXHRObject, EventEmitter);

AbstractXHRObject.prototype._start = function(method, url, payload, opts) {
  var self = this;

  try {
    this.xhr = new XHR();
  } catch (x) {
    // intentionally empty
  }

  if (!this.xhr) {
    debug('no xhr');
    this.emit('finish', 0, 'no xhr support');
    this._cleanup();
    return;
  }

  // several browsers cache POSTs
  url = urlUtils.addQuery(url, 't=' + (+new Date()));

  // Explorer tends to keep connection open, even after the
  // tab gets closed: http://bugs.jquery.com/ticket/5280
  this.unloadRef = utils.unloadAdd(function() {
    debug('unload cleanup');
    self._cleanup(true);
  });
  try {
    this.xhr.open(method, url, true);
    if (this.timeout && 'timeout' in this.xhr) {
      this.xhr.timeout = this.timeout;
      this.xhr.ontimeout = function() {
        debug('xhr timeout');
        self.emit('finish', 0, '');
        self._cleanup(false);
      };
    }
  } catch (e) {
    debug('exception', e);
    // IE raises an exception on wrong port.
    this.emit('finish', 0, '');
    this._cleanup(false);
    return;
  }

  if ((!opts || !opts.noCredentials) && AbstractXHRObject.supportsCORS) {
    debug('withCredentials');
    // Mozilla docs says https://developer.mozilla.org/en/XMLHttpRequest :
    // "This never affects same-site requests."

    this.xhr.withCredentials = true;
  }
  if (opts && opts.headers) {
    for (var key in opts.headers) {
      this.xhr.setRequestHeader(key, opts.headers[key]);
    }
  }

  this.xhr.onreadystatechange = function() {
    if (self.xhr) {
      var x = self.xhr;
      var text, status;
      debug('readyState', x.readyState);
      switch (x.readyState) {
      case 3:
        // IE doesn't like peeking into responseText