Expect KafkaOperations instead of KafkaTemplate for AbstractKafkaListenerContainerFactory#setReplyTemplate

[neshkeev]

Expected Behavior

It should be possible to pass an implementation of KafkaOperations instead of KafkaTemplate into KafkaListenerContainerFactory since extending KafkaTemplate might not always be possible (no default constructor).

Current Behavior

Here is a custom implementation of KafkaOperations:

class MyCustomKafkaOperationsImpl implements KafkaOperations<Object, Object> {
    ...
}

Unfortunately, I cannot pass an instance of MyCustomKafkaOperationsImpl inside KafkaListenerContainerFactory:

@Configuration
public class MyConfig {

    public ConcurrentKafkaListenerContainerFactory<Object, Object> containerFactory() {
        var factory = new ConcurrentKafkaListenerContainerFactory();
        factory.setReplyTemplate(new MyCustomKafkaOperationsImpl()); // IMPOSSIBLE
        return factory;
    }
}

Context

Direct extension of KafkaTemplate might be impossible since its constructors requires at least a ProducerFactory object.
I briefly scanned over the code base, I didn't find any places which require KafkaTemplate specific methods, all send operations come from KafkaOperations

[sobychacko]

@neshkeev I think this is a reasonable request (as far as I can see). Would you be open to sending a PR for this? Then, we can review it and make sure that there are no side effects.

[neshkeev]

@sobychacko , please approve my PR so it can trigger a build

[artembilan]

As a project stewarded by US company, we are unable to accept contributions from Russian sources due to US law at this time.

[neshkeev]

@artembilan , I understand, no hard feelings.

Please consider implementing this idea yourself