({
    connectCometd : function(component, event, helper)
    {
        var _connected = false;
        // functions that manage connection status with Bayeux server
        
        function _metaConnect(message)
        {
            if (cometd.isDisconnected())
            {
                _connected = false;
                console.log("❗ CometD connection closed.");
                component.set("v.Connected", false);
                return;
            }

            var wasConnected = _connected;
            _connected = message.successful === true;
            if(!wasConnected && _connected){
                console.log("✅ CometD connection established.");
               component.set("v.Connected", true);
            }else if (!wasConnected && !_connected)
            {
                console.log("❗ CometD connection broken.");
                component.set("v.Connected", false);
            }
        }

        function _metaUnsuccessfulListener(message){
            console.log('DEBUG: /meta/unsuccessful Error: ' + JSON.stringify(message)+ '<br>');
            helper.disconnectCometd(component);
            setTimeout(function(){
                console.log('Init of CometD failed');
                try{
                    cometd.handshake();
                }catch(e){
                    console.log('_metaUnsuccessful was unsuccessful in reestablishing connection: ' + e);
                }
            }, 5000);
        }

        // _metaHandshake makes subscribe conditional on successful handshake
        function _metaHandshake(handshake)
        {
            if(handshake.successful)
            {
                console.log('🤝 Handshake successful, clientId: '+ handshake.clientId);
                
                // Subscribe to pushTopic
                var newSubscription = cometd.subscribe("/topic/MyTopicReceived",
                    function(pushTopic)
                    {
                        console.log('My topic received, Parameters: '+ pushTopic.data.sobject[ParamField]);
                        var appEvent = $A.get("e.c:TopicReceived");
                        appEvent.setParams({
                            ObjectId: pushTopic.data.sobject[ParamField]
                        }).fire();
                        console.log("🔥🔥Received PushTopic, fired Application Event: " + pushTopic.data.sobject[ParamField]);
                    });
                var subscriptions = component.get("v.cometdSubscriptions");
                subscriptions.push(newSubscription);
                component.set("v.cometSubscriptions", subscriptions);
            }
            else
                console.error("❗ CometD handshake error: " + handshake.error);
        }

        // Configure CometD


        var cometdUrl = '/cometd/42.0/';
        var cometd = component.get('v.cometd');
        cometd.websocketEnabled = false;
        cometd.configure({
            url: cometdUrl,
            requestHeaders: { Authorization: "OAuth " + component.get("v.sessionId")},
            appendMessageTypeToURL : false
        });

        //add listeners
        cometd.addListener('/meta/handshake', _metaHandshake);
        cometd.addListener('/meta/connect', _metaConnect);
        cometd.addListener('/meta/unsuccessful', _metaUnsuccessfulListener);
        cometd.addListener('/meta/disconnect', function(message){
            console.log('disconnect: ' +  JSON.stringify(message));
        });
        cometd.addListener('/meta/subscribe', function(message){
            console.log('subscribe: ' + JSON.stringify(message));
            console.log('Subscriptions: ' + JSON.stringify(component.get("v.cometdSubscriptions")));
        });
        cometd.addListener('/meta/unsubscribe', function(message){
            console.log('unsubscribe: ' +  JSON.stringify(message));
        });

        try{
            cometd.handshake();
        }catch(e){
            cometd.handshake();
            console.log(e);
        }
    },

    disconnectCometd : function(component)
    {
        var cometd = component.get('v.cometd');

        // Unsuscribe all CometD subscriptions
        cometd.batch(function() {
            var subscriptions = component.get('v.cometdSubscriptions');
            subscriptions.forEach(function (subscription) {
            cometd.unsubscribe(subscription);
            });
        });
        component.set('v.cometdSubscriptions', []);

        // Disconnect CometD
        cometd.disconnect();
        console.log('🐝 CometD disconnected.');
    },
})

public with sharing class CometDgetSessionId {
    @AuraEnabled
    public static String getUserSessionId() {
        return UserInfo.getSessionId();
    }


    @AuraEnabled
    public static String[] setupPushTopic() {

     // push topic setup code

   }

}