Failed to load resource error handling

Question

I have been doing some nodeJS testing with socket.io and have noticed when i don't run the nodeJS my client errors.

When nodeJS is not running I get this error in my client console.log:

Failed to load resource socket.io/socket.io.js

My client code is like this:

<script src = "socket.io/socket.io.js" > < /script> 
<script>
window.onload = function(){

 if(typeof io != 'undefined'){
     socketio = io.connect("[hidden]:[hidden]");            

     socketio.on('error', function(err) {       
         if(err === 'handshake error') {
            console.log('handshake error', err);
         } else {
            console.log('io error', err);
         }  
    });
 } else {
    console.log('IO not started?');
 }

}
</scirpt>

So i'm wondering - whats the best way to preiodically check when nodeJS has started up ?

Answer 1

you can send a request to your nodejs server,if server return 500. nodejs is stopping now.

<script>
  var socket = io.connect();
  socket.on('connect', function(){
    console.log('connected');
    //do Something...      
  })

</script>

if you want to check socket.io.js whether it has finished loading, you can try to use Require.js http://requirejs.org/

Answer 2

Not an elegant solution, but this should solve your problem -

<script src="http://code.jquery.com/jquery-1.10.2.min.js"></script>
<script>
$(document).ready(function(){
  var connected = 0;
  var socket;
  var timer = setInterval(function(){
    loadScript();
  },1000);

  function loadScript() {
  $.getScript("http://<ip>:<port>/socket.io/socket.io.js")
      .done(function( script, textStatus ) {
        //console.log( textStatus );
        if(!connected) {
          socket = io.connect('http://<ip>:<port>');
          connected = 1;
          clearInterval(timer);
        }
      });
  }
});
</script>