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How listen the arrival of the message on the inboud-endpoint in mule esb 3.9 without explicit code?

I have the classic AOP requirement: Intercept some event and modify o audit it.
< custom-processor >
https://gist.github.com/cmordue/4552292
Works very well but I need to insert directly into flow. This is what I don't want due to my dozens of flows
<flow>
<some-inboud/>
<custom-processor class="org.acme.Audit" />
<logic>
</flow>
Mule Server Notifications
MessageProcessorNotificationListener
https://gist.github.com/jrichardsz/cdd235f9b723074e54af27b3639ca59e#file-notificator-java
Works very well because I don't need to add it to all flows.
public class Auditor MessageProcessorNotificationListener<MessageProcessorNotification>{
#Override
public void onNotification(MessageProcessorNotification notification) {
MuleEvent ev = notification.getSource();
MuleMessage msg = ev.getMessage();
Object payload = msg.getPayload();
System.out.println("auditor");
//etc
}
}
I just need to add as spring bean and register it as notification:
When I run this project my auditor catch any step of the flow: transformers, components, scripts and the final outbound event.
The problem
My audit logic need just catch the initial event, when a message arrive to flow using the inbound(http, jms, etc).
Mule Server Notification documentation says that we can configure any type of listener for different events but just MessageProcessorNotificationListener works.
Attempts
I read the documentation to enable notifications just for connector events with no luck:
https://docs.mulesoft.com/mule-runtime/3.9/notifications-configuration-reference#notification-types
ASYNC-MESSAGE ,CONNECTION ,CONNECTOR-MESSAGE ,CONTEXT ,CUSTOM ,EXCEPTION ,EXCEPTION-STRATEGY ,EXTENSION ,MANAGEMENT ,MESSAGE-PROCESSOR ,PIPELINE-MESSAGE ,ROUTING ,SECURITY ,TRANSACTION
In permutations with
org.mule.api.context.notification.ConnectorMessageNotificationListener
org.mule.api.context.notification.ConnectionNotificationListener
Also some post says that Mule Server Notifications works just in Anypoint Studio and not in mule standalone server :s
Workaround
Use MessageProcessorNotificationListener and perform my audit just for the first invocation with a global boolean variable isFirsTime
Question
How listen the arrival of the message on the inboud-endpoint in mule esb without explicit code and or with Mule Server Notification approach?

Spingboot Websocket Stomp

Could anyone tell me if the server-side implementation is using stomp WebSocket, is the client also expected to implement stomp?
I am trying to implement a spring boot application and I am confused if I should go with or without stomp implementation. From my research, I understand, if you want to scale the application, it is better to use stomp and embedded broker( RabbitMQ for eg.) as it will handle the sessions, heartbeat etc. instead of an in-memory broker.
The examples available online just shows implementations with and without stomp.
I am basically trying to get different datasets from the table upon client request and write to a WebSocket continuously.
Could anyone please confirm if my understanding so far is correct?
What are the essential things I will have to take care of if I go with stomp + websocket?
Updating the usecase below:
The mobile client would be displaying charts upon user login. There would be links in the left panel for eg. Sales, Discounts etc. which upon clicking, the request will reach server through websocket channel. Server will check the datatype in the request, generate the model using data from DB and write the data to the websocket.
Updating code - v1
MyWebSocketHandler:
#Component
public class MyWebSocketHandler extends TextWebSocketHandler {
Logger logger = LoggerFactory.getLogger(getClass());
#Autowired
DashboardUtil dashboardutil;
#Resource(name = "socketSessionsMap")
private Map<String, WebSocketSession> socketSessionsMap;
#Override
public void handleTextMessage(WebSocketSession session, TextMessage message)
throws InterruptedException, IOException {
try {
//Gets the socket session from map and writes a json to that socket - did for testing purpose.
socketSessionsMap.put("session", session);
//String payload = message.getPayload();
String jsonString = dashboardutil.getDataInJSON(); // gets hardcoded json model
session.sendMessage(new TextMessage(jsonString));
} catch (Exception e) {
e.printStackTrace();
}
}
#Override
public void afterConnectionEstablished(WebSocketSession session) throws Exception {
}
#Override
public void afterConnectionClosed(WebSocketSession session, CloseStatus status) throws Exception {
}
}
WebSecurityConfig:
#Configuration
#EnableWebSocket
public class WebSocketConfig implements WebSocketConfigurer {
#Autowired
private MyWebSocketHandler myWebSocketHandler;
#Override
public void registerWebSocketHandlers(WebSocketHandlerRegistry registry) {
registry.addHandler(myWebSocketHandler, "/socketHandler").setAllowedOrigins("*").withSockJS();
}
}

Could anyone tell me if the server-side implementation is using stomp
WebSocket, is the client also expected to implement stomp?
You can register multiple handlers in your web socket configuration. So in theory you can provide a handler for STOMP and another one for plain web socket. If you only provide a STOMP handler then the handshake from a standard web socket client will fail.
From my research, I understand, if you want to scale the application,
it is better to use stomp and embedded broker( RabbitMQ for eg.) as it
will handle the sessions, heartbeat etc. instead of an in-memory
broker.
That's correct. STOMP also offers a few more nice features especially the subscription to certain endpoints.
I am basically trying to get different datasets from the table upon
client request and write to a WebSocket continuously.
That's a really simple description ...
You should think about if you need to share sessions across multiple instances or if you need to send messages between web socket sessions.
From your description it sounds like you just accept a web socket connection and continuously push data to the client. If you want to scale this application you can just put a load balancer in front of your instances and you are good to go.

How to work with rabbitTemplate receiveAndReply

I have just started experimenting with Spring and rabbitMQ.
I would like to create a microsevice infrastructure with rabbit and spring,
I have been following Spring boot tutorial
But it is very simplistic. As well I am looking at the documentation (springs, Rabbit) for how to create an RPC, i understand the Rabbits approach, but i would like to leverage Spring template to save me the boilerplate.
I just cant seem to understand where to register the reciveAndReplay callback at.
I tried doing this:
sending
System.out.println("Sending message...");
Object convertSendAndReceive = rabbitTemplate.convertSendAndReceive("spring-boot", "send and recive: sent");
System.out.println("GOT " + convertSendAndReceive); //is null
receiving
#Component
public class Receiver {
#Autowired
RabbitTemplate rabbitTemplate;
public void receiveMessage(String message) {
this.rabbitTemplate.receiveAndReply("spring-boot", (Message)->{
return "return this statement";
});
}
}
But its not a big surprise this doesn't work the message is received but nothing comes back. I assume that this needs to be registered somewhere in the factory/template at the bean creation level but i don't seem to understand where and sadly the documentation is unclear.

First, please use the Spring AMQP Documentation.
You would generally use a SimpleMessageListenerContainer wired with a POJO listener for RPC.
The template receiveAndReply method is intended for "scheduled" server-side RPC - i.e. only receive (and reply) when you want to, rather than whenever a message arrives in the queue. It does not block waiting for a message.
If you want to use receiveAndReply(), there's a test case that illustrates it.
EDIT:
This code...
this.template.convertAndSend(ROUTE, "test");
sends a message to the queue.
This code...
this.template.setQueue(ROUTE);
boolean received = this.template.receiveAndReply(new ReceiveAndReplyMessageCallback() {
#Override
public Message handle(Message message) {
message.getMessageProperties().setHeader("foo", "bar");
return message;
}
});
Receives a message and from that queue; adds a header and returns the same messsage to the reply queue. received will be false if there was no message to receive (and reply to).
This code:
Message receive = this.template.receive();
receives the reply.
This test is a bit contrived because the reply is sent to the same queue as the request. We can't use sendAndReceive() on the client side in this test because the thread would block waiting for the reply (and we need to execute the receiveAndReply()).
Another test in that class has a more realistic example where it does the sendAndReceive()s on different threads and the receiveAndReply()s on the main thread.
Note that that test uses a listener container on the client side for replies; that is generally no longer needed since the rabbit broker now supports direct reply-to.
receiveAndReply() was added for symmetry - in most cases, people use a listener container and listener adapter for server-side RPC.

Weblogic Websocket endpoint not working

I'm trying to crete a simple Websocket application based on tutorial here: http://docs.oracle.com/javaee/7/tutorial/doc/websocket004.htm
So the code looks something like this:
#ServerEndpoint("/echo")
public class EchoEndpoint {
#OnMessage
public void onMessage(Session session, String msg) {
try {
session.getBasicRemote().sendText(msg);
} catch (IOException e) { ... }
}
}
I'm running Weblogic 12c. I thought the annotation should be automatically picked up and websocket endpoint created on the address localhost:8888/myApp/echo, but when I try to connect there with this js test: http://www.websocket.org/echo.html, nothing happens. Also when I attach debugger, I see that the EchoEndpoint class was not loaded. What else should I do to make it running? I see nothing else in the Oracle tutorial

The Tyrus library requires a JEE7 container, Weblogic only supports JEE6.
Follow this tutorial to get websockets in Weblogic.
http://docs.oracle.com/middleware/1212/wls/WLPRG/websockets.htm

How to detect broken/recovered JMS connection in Apache Camel?

We are building an integration project using Apache Camel (Camel 2.10.3, Java DSL based).
We have a route that extracts data from a database (lets call it IN_DB), does some logic and inserts into another database (OUT_DB) once a day, and another route that subscribes to a JMS topic for XML data, does some logic and inserts it into the same database (OUT_DB) throughout the day.
The requirement is that when the JMS topic connection goes down for whatever reason, we keep trying to reconnect indefinitely, and once reconnection is successful we need to go back to the database (IN_DB) and do another load to fill in the gap where the topic was down.
My question is how can we do this logic ('I was connected then I got disconnected and now I am connected again') in Camel? What happens to the route that starts with a topic consumer when the topic goes down, will the route just stop? Or will it issue an error message to some error queue? Do I have to write my own handler to monitor the topic connection, or will Camel automatically reconnect when the topic comes back up and set some message header, or set some context variable to indicate that the 'I was connected then I got disconnected and now I am connected again' scenario has happened? I am happy building the route logic around calling the database load I just can't figure out the best way to 'detect' in Camel that this scenario has happened.
Any suggestions much appreciated.

In terms of the reconnecting to your queue, it depends on what JMS broker you are using. If you are using ActiveMQ then you can configure how it reconnects through the URI so it can try and reconnect to another broker, reconnect to the same broker after a timeout etc. The docs for it are here.
To detect when the connection has failed, the easiest from the point of the view of the program is to just use persistent queues instead of topics. However, assuming that isn't feasible then I think you've got two options.
Define a JMS exception listener. This should let you know when the underlying connection has disappeared.
To detect when its back up again I think you're stuck with posting a message to a particular topic and watching for messages from this topic in another route. When you read a message on this topic, you know the broker has come back up so you can reload your data from the DB.
or 2. You could post regular hearbeat messages onto your JMS topic. If you stop receiving them you know the broker has gone down. Once you start to get them again, you know it is back up and you need to reload data from the DB.

Sorry to answer some years later ! I was looking for a solution for this problem since a few days, in order to supervising an AMQP connection in an Apache Camel application.
I finally find a way, I do not know if in the last Camel versions (i am using 2.25.4), it is possible do listen more "natively" the JMS connection changes :
The JMS consumer route must use the option "messageListenerContainerFactory" in the URL : "messageListenerContainerFactory=#customJmsListernerContainerFactory"
The factory would be instancied before of course and added to a registry associated to the camel context :
MessageListenerContainerFactory customJmsListenerContainerFactory = new CustomJmsListenerContainerFactory();
this.registry.put("customJmsListernerContainerFactory", customJmsListenerContainerFactory);
not working on producer, for this kind, you must add an exception clause :
onException(javax.jms.JMSException.class)...
create the class CustomJmsListenerContainerFactory used above, implementing MessageListenerContainerFactory :
public class CustomJmsListenerContainerFactory implements MessageListenerContainerFactory {
#Override
public AbstractMessageListenerContainer createMessageListenerContainer(JmsEndpoint endpoint) {
CustomJmsListenerContainer customJmsListener = new CustomJmsListenerContainer();
return customJmsListener;
}
create a class CustomJmsListenerContainer extending DefaultMessageListenerContainer AND implementing JmsConnectionListener. The trick is to ovveride createConnection, in order to temporary get the created connection in order to manually add a listener (the container itself):
public class CustomJmsListenerContainer extends DefaultMessageListenerContainer implements JmsConnectionListener {
protected Connection createConnection() throws JMSException {
JmsConnection myConnection = (JmsConnection)super.createConnection();
this.myConnection.addConnectionListener(this);
return myConnection;
}
#Override
public void onConnectionEstablished(URI remoteURI) {
LOGGER.info("JMS connection detected");
#Override
public void onConnectionFailure(Throwable error) {
LOGGER.info("JMS connection failure");
}
#Override
public void onConnectionInterrupted(URI remoteURI) {
LOGGER.info("JMS connection interrupted");
#Override
public void onConnectionRestored(URI remoteURI) {
LOGGER.info("JMS connection restored");
#Override
public void onInboundMessage(JmsInboundMessageDispatch envelope) {
// TODO Auto-generated method stub
}
#Override
public void onSessionClosed(Session session, Throwable cause) {
// TODO Auto-generated method stub
}
#Override
public void onConsumerClosed(MessageConsumer consumer, Throwable cause) {
// TODO Auto-generated method stub
}
#Override
public void onProducerClosed(MessageProducer producer, Throwable cause) {
// TODO Auto-generated method stub
}
}