[Feature Request] Reactor Kafka channel adapter

[rolkhas2]

Expected Behavior
I'd expect there to be full Apache Kafka support since this is one of the most popular technologies, but for some reason, I didn't see any reactive Kafka channel adapter. That prevents me from using the adapter. I also didn't manage to understand if there's an async Kafka channel adapter, so if there is I think that can get documented better.

Current Behavior
Only Spring-Kafka support. No relation with Reactor-Kafka.

Context
I'm trying to build a simple data pipeline in the Reactive Spring Integration way.

[artembilan]

It is possible at the moment with a combination of Reactor Kafka and MessageProducerSupport.subscribeToPublisher(Publisher<? extends Message<?>> publisher): https://docs.spring.io/spring-integration/docs/current/reference/html/reactive-streams.html#event-driven-channel-adapter.
Or there is a nice trick via ReactiveMessageSourceProducer and existing KafkaMessageSource. See the same doc.

We definitely will look into reactive channel adapters for Apache Kafka somewhere in the future.

[artembilan]

BTW, the logic for Reactor Kafka channel adapters really might be borrowed from a new Reactor Kafka binder in Spring Cloud Stream: https://github.com/spring-cloud/spring-cloud-stream/blob/main/binders/kafka-binder/spring-cloud-stream-binder-kafka-reactive/src/main/java/org/springframework/cloud/stream/binder/reactorkafka/ReactorKafkaBinder.java

[rolkhas2]

@artembilan yes you're right. That's pretty simple to create such binders (shouldn't take more than a couple of hours). I'll try to implement that later.

[rolkhas2]

Super improtant though