Websocket

var WebsocketClass = function(host){
               this.socket = new WebSocket(host);
        }

        var current_interval_id;
        var reconnecting_attempt = false;
        WebsocketClass.prototype = {
               initWebsocket : function(){
                       var $this = this;
                       this.socket.onmessage = function(e){
                               $this._onMessageEvent(e);
                       };
                       this.socket.onclose = function(){
                               $this._onCloseEvent();
                       };
                       this.socket.onopen = function() {
                               $this._onOpenEvent();
                       }
                       this.socket.onerror = function() {
                               $this._onCloseEvent();
                       }
               },
               initAutoSend : function(){
                    var $this = this;
                    current_interval_id = setInterval(function(){$this.socket.send('update')}, {{ settings.updatetime }})
               },
               _onOpenEvent : function() {
                    Messenger().post({
                      message: 'Connected to Server.',
                      type: 'success'
                    });
               },
               _onMessageEvent : function(e){
                    var parsed = JSON.parse(e.data);
                    if (parsed['received'] == 'update') {
                        $("#cpuload").text(parsed['cpu']+" %");
                        $("#ram").text(parsed['ram']+" %");
                        $("#disk").text(parsed['disk']+" %");
                    }
                    else {
                        Messenger().post({
                          message: parsed['received'],
                          type: 'success'
                        });
                    }
               },
               _onCloseEvent : function(){
                    window.clearInterval(current_interval_id)
                    if(reconnecting_attempt == false) {
                        reconnecting_attempt = true;
                        var connect = 0;
                        window.clearInterval(current_interval_id);
                        $('#cpuload').text('');
                        $('#cpuload').prepend("<img src='/static/img/loading.gif' />")
                        $('#ram').text('');
                        $('#ram').prepend("<img src='/static/img/loading.gif' />")
                        $('#disk').text('');
                        $('#disk').prepend("<img src='/static/img/loading.gif' />")
                        Messenger().run({
                            errorMessage: 'Disconnected from Server',
                            action: function(opts) {
                                if(connect == 0) {
                                    connect = 1;
                                    return opts.error({
                                        status: 500,
                                        readyState: 0,
                                        responseText: 0
                                    });
                                }
                                ws = new WebsocketClass("ws://127.0.0.1:8000/_socket_system");
                                ws.initWebsocket();
                                ws.initAutoSend();
                                reconnecting_attempt = false;
                                return opts.success();
                            }
                        });
                    }
               }
        };

        // Initialize a new websocket (the first one)
        var ws = new WebsocketClass("ws://127.0.0.1:8000/_socket_system");
        window.setTimeout('ws.initWebsocket()', 500);
        ws.initAutoSend();

        // Before changing the page, we close the socket correctly.
        window.onbeforeunload = function() {
            ws.socket.onclose = function () {};
            ws.socket.close()
        };