@RetryableTopic for multi-handler kafka listener

[Abdelhady]

A listener with multi-handler like this works fine, where I can listen to different message formats at once:

@Component
@RequiredArgsConstructor
@KafkaListener(topics = "${kafka.topic.name}", groupId = "${kafka.group.id}")
public class DemoListener {
    
    private final DemoService demoService;
    
    @KafkaHandler
    public void handleFooMessage(Foo foo) {
      demoService.handleFoo(foo);
    }
    
    @KafkaHandler
    public void handleBarMessage(Bar bar) {
      System.out.println("bar received: " + bar);
    }
    
    @KafkaHandler(isDefault = true)
    public void unknown(Object object) {
      System.out.println("Unkown type received: " + object);
    }
}

where I just need to use this in applicaiton.properties

spring.kafka.consumer.key-deserializer=org.apache.kafka.common.serialization.StringDeserializer
spring.kafka.consumer.value-deserializer=org.springframework.kafka.support.serializer.JsonDeserializer
spring.kafka.consumer.properties.spring.json.trusted.packages=*

Now, I need to use @RetryableTopic for retry/backoff/dlt handling, but it can't be used with the @kafkaHandler and can't be added to the whole class, it has to be added to a method like:

@KafkaListener(topics = "${kafka.topic.name}", groupId = "${kafka.group.id}")
@RetryableTopic(
  backoff = @Backoff(
    delay = 2000,
    maxDelay = 5000,
    multiplier = 2
  ),
  attempts = "5"
)
public void handleFoo(Foo foo) throws Exception {
 demoService.handleFoo(foo);
 // throw new Exception("test exception");// To test retries
}

Question is

How can I mix the 2 approaches, to be able to listen to Foo & Bar and also add a @RetryableTopic to them?

[artembilan]

Just gave you an answer in your StackOverflow question: https://stackoverflow.com/questions/77819812/retryabletopic-for-multi-handler-kafka-listener.

Please, don't duplicate same question in different places.