test.js

/* wsHook.js
 * https://github.com/skepticfx/wshook
 * Reference: http://www.w3.org/TR/2011/WD-websockets-20110419/#websocket
 */

var wsHook = {};
(function() {
  // Mutable MessageEvent.
  // Subclasses MessageEvent and makes data, origin and other MessageEvent properites mutatble.
  function MutableMessageEvent(o) {
    this.bubbles = o.bubbles || false;
    this.cancelBubble = o.cancelBubble || false;
    this.cancelable = o.cancelable || false;
    this.currentTarget = o.currentTarget || null;
    this.data = o.data || null;
    this.defaultPrevented = o.defaultPrevented || false;
    this.eventPhase = o.eventPhase || 0;
    this.lastEventId = o.lastEventId || "";
    this.origin = o.origin || "";
    this.path = o.path || new Array(0);
    this.ports = o.parts || new Array(0);
    this.returnValue = o.returnValue || true;
    this.source = o.source || null;
    this.srcElement = o.srcElement || null;
    this.target = o.target || null;
    this.timeStamp = o.timeStamp || null;
    this.type = o.type || "message";
    this.__proto__ = o.__proto__ || MessageEvent.__proto__;
  }

  var before = wsHook.before = function(data, url) {
    return data;
  };
  var after = wsHook.after = function(e, url) {
    return e;
  };
  wsHook.resetHooks = function() {
    wsHook.before = before;
    wsHook.after = after;
  }

  var _WS = WebSocket;
  WebSocket = function(url, protocols) {
    var WSObject;
    this.url = url;
    this.protocols = protocols;
    if (!this.protocols)
      WSObject = new _WS(url);
    else
      WSObject = new _WS(url, protocols);

    var _send = WSObject.send;
    var _wsobject = this;
    WSObject.send = function(data) {
      data = wsHook.before(data, WSObject.url) || data;
      _send.apply(this, arguments);
    }

    // Events needs to be proxied and bubbled down.
    var onmessageFunction;
    WSObject.__defineSetter__('onmessage', function(func) {
      onmessageFunction = func;
    });
    WSObject.addEventListener('message', function(e) {
      e = new wsHook.after(new MutableMessageEvent(e), this.url) || e;
      e = new MessageEvent(e.type, e);
      onmessageFunction.apply(this, [e])
    });

    return WSObject;
  }
})();