javascript websocket onmessage event.data

Question

Using JavaScript WebSocket how to pass event.data out onMessage function?

var eventData = EventRequest("text");


  ..... codes .....


EventRequest = function (text)
{
   var socket = new WebSocket ('ws://localhost:8080/');
   websocket.onopen = function(evt) { onOpen(evt); };
   websocket.onmessage = function(evt) { onMessage(evt); };

function onOpen (evt)
{
   socket.send("text");
}

function onMessage (evt)
{
   alert (evt.data);
   return evt.data;
}
};

I tried different ways to pass evt.data out, but I have not been able to. I can see the correct evt.data data. I just can not pass the data out of onMessage function.

I tried

function wcConnection (){
   this.dataInput = '';
}

Inside onMessage function, I added

function onMessage (evt)
{
   alert (evt.data);
   this.dataInput = evt.data;
}

Any help would be appreciated.

Answer 1

If you server is python tornado

def on_message(self, message):
        t = json.dumps(['foo', {'bar': ('baz', None, 1.0, 2)}])
        self.write_message(t)

In your client, to retrieve the message, you could do

ws.onmessage = function (evt) { 
    console.log(JSON.parse(event.data));
}

you should see the json in the console