1 (function(){

     2     var relative_URI = window.location.href.replace(/^http(s?:\/\/[^\/]*)\/.*$/, 'ws$1/ws');

     3     var ws = new WebSocket(relative_URI);

     4     ws.onmessage = function (evt) {

     5         var received_msg = evt.data;

     6         alert("Message is received..."+received_msg); 

     7     };

     8     ws.onopen = function (evt) {

     9         ws.send("test");

    10     };

    11 })();