socket.io doesn't work on EC2

Question

I'm doing a new feature that allow show system logs on admin page. I'm using gevent-socketio (0.3.6). Everything works fine on my local machine but when i deploy my code to EC2, it doesn't work.

Here is client code:

// notification socketio
var socket_notification = io.connect('/notification');

// Update when we get new data from the server
socket_notification.on('data', function (data) {
    $scope.notifications.push(data);
    $scope.total_noti.push(data);

});

That's what i see in firefox console :

GET http://mybackend.com/socket.io/1/?t=1460013461586 200 OK 466ms

It seems that socket connected successful but i can't get any thing from server.

Here is my backend code:

@route(bp, '/socket.io/<path:remaining>')
def socketio(remaining):
    print('connected')
    try:
       app = current_app._get_current_object()
       socketio_manage(request.environ, {'/notification': LiveNotificationNamespace, '/log': LiveLogNamespace}, app)
    except:
        current_app.logger.error("Exception while handling socketio connection",
                             exc_info=True)
    return Response()

I added a print command to test but it doesn't print any thing. I already updated Varnish config to run websockets through Varnish:

sub vcl_pipe {
 if (req.http.upgrade) {
     set bereq.http.upgrade = req.http.upgrade;
 }
}
sub vcl_recv {
 if (req.http.Upgrade ~ "(?i)websocket") {
     return (pipe);
 }
}

Do i need configure anything on EC2 or something like that?

Thank you.