manual message acknowledgement is broken in 2.x with a MessageListener and requeueOnMessageListenerException=true

[lepurvis-fadv]

Describe the bug

Calling Message.acknowledge() from inside MessageListener.onMessage() is basically a no-op if RMQConnectionFactory.setRequeueOnMessageListenerException(true) and the RMQSession is created with CLIENT_INDIVIDUAL_ACKNOWLEDGE or CLIENT_ACKNOWLEDGE - the acknowledgement is never sent to the rabbitmq server.

In com.rabbitmq.jms.client.RMQSession.acknowledge(long) line 1336 unackedMessageTags is always empty.

This is due to com.rabbitmq.jms.client.MessageListenerConsumer.handleDelivery(String, Envelope, BasicProperties, byte[]) not calling dealWithAcknowledgments() before calling the MessageListener when this.requeueOnMessageListenerException is true. dealWithAcknowledgments() in turn calls back to the session, which is what populates unackedMessageTags.

The fix is more involved than just reordering dealWithAcknowledgments() as is done when this.requeueOnMessageListenerException is false, as when it is true, it shouldn't be called if the message needs to be nacked.

So somehow com.rabbitmq.jms.client.RMQSession.unackedMessageTags needs to be populated before dispatching a message to a MessageListener.

Reproduction steps

1. Configure RMQConnectionFactory with setRequeueOnMessageListenerException(true)
2. Create a session with RMQSession.CLIENT_INDIVIDUAL_ACKNOWLEDGE
3. Create a MessageConsumer on a Queue
4. Set a MessageListener on the MessageConsumer
5. Observe that Message.acknowledge() from onMessage() is a silent no-op (no exception is thrown)
   ...

Expected behavior

javax.jms.Message.acknowledge() should acknowledge the message as defined by the JMS spec, i.e. the rabbitmq server should receive an ack for the message.

Additional context

No response

[michaelklishin]

@lepurvis-fadv please put together an executable example we can use to reproduce. Server logs and/or a traffic capture would also help.

"It should work" is not a behavior we can reason about but an executable example usually clarifies a lot.

[lepurvis-fadv]

@lepurvis-fadv please put together an executable example we can use to reproduce. Server logs and/or a traffic capture would also help.

"It should work" is not a behavior we can reason about but an executable example usually clarifies a lot.

@michaelklishin I meant it should work as defined by the JMS spec. The message should be acknowledged, but it is not. There isn't any network traffic to capture when javax.jms.Message.acknowledge() is called under the conditions I outlined, because the underlying code never generates any traffic. I verified this in both a debugger and by attaching a com.rabbitmq.client.TrafficListener to the com.rabbitmq.client.ConnectionFactory.

What rabbitmq server should my reproducing example connect to for you to be able to run it? localhost? Do I need to provide scripts to setup a queue?

The client-side code to reproduce the issue is very small, but I don't know what you expect in terms of server setup (nothing specific on the server-side needs to be done, any arbitrary queue will work).

[michaelklishin]

@lepurvis-fadv we are not picky about executable examples, as long as we understand how to run the app.

A tiny app that connects to localhost or a Docker Compose in a public repo would do. Thank you.