KafkaHeaders.DELIVERY_ATTEMPT is not added for batch listeners

[lm231290]

Version 3.3.2

When using blocking retries for a batch listener, the attempt number is not coming in DELIVERY_ATTEMPT header even if setting setDeliveryAttemptHeader(true)

The method KafkaMessageListenerContainer.ListenerConsumer.internalHeaders is called only in
ConsumerRecord<K, V> checkEarlyIntercept(ConsumerRecord<K, V> recordArg) which is used for a regular listener, and is not called in
ConsumerRecords<K, V> checkEarlyIntercept(ConsumerRecords<K, V> nextArg) which is used for a batch listener

[lm231290]

If the whole batch fails, the retry behavior would be pretty much same as if the first record in a batch fails, is my assumption correct?
So If the header is added for batchListenerFailedException, I think it can also be added for any other (whole batch) errors as it would for batchListenerFailedException.index = 0

[artembilan]

I'm not sure what you mean with a BatchListenerFailedException analogy, but I'd be happy to review some contribution for better understanding how this request could be fixed.
Thanks

[artembilan]

The logic around this header is not that simple as it sounds.
See FailedRecordTracker for details.

[lm231290]

Seems like my analogy with BatchListenerFailedException is incorrect.

So my suggestion would be to call
KafkaMessageListenerContainer.internalHeaders or
KafkaMessageListenerContainer.checkEarlyIntercept from
KafkaMessageListenerContainer.doInvokeBatchListener and
KafkaMessageListenerContainer.invokeBatchListenerInTx.

Currently KafkaMessageListenerContainer.checkEarlyIntercept is called only from
KafkaMessageListenerContainer.invokeRecordListenerInTx and
KafkaMessageListenerContainer.doInvokeWithRecords

[artembilan]

That's correct. But the problem with the rest of missing API that we deal with the whole batch.
Therefore it is not clear how to inject that KafkaHeaders.DELIVERY_ATTEMPT header and handle it respectively.

If you have anything in mind, feel free to open pull request and we gladly review it.

[lm231290]

I am not so deep into the code, are there any contributors who could take care of it? Maybe the issue should be promoted as a feature request?

[artembilan]

Sure! Any one can take an issue for contribution.
I am personally, don't see a quick and easy solution, and with limited amount of time resources on my side, not willing to dive deep to the problem which was note advertised before anyway.

[sobychacko]

@lm231290 We will keep this in the backlog for the time being. If there is an urgent need for anyone in the community, they can design a solution and contribute a PR. If not, we will take a look at this as time permits.