Spring cloud stream 4.x metadatachannel

Question

want to get the output channel name after message is published to the destination.

metadata channel is not available in 4.x spring.cloud.stream.kafka.bindings.myBinding.producer.**record-metadata-channel**

Spring cloud stream : 4.0.1

binder type : Kafka

Answer 1

This works for me with version 4.0.1. When the supplier is invoked and the message is published to the Kafka topic, the handler method on the record metadata channel is called. I can see the sent message in the output. What is not working in your application?

@SpringBootApplication
public class So75681179Application {

    public static void main(String[] args) {
        SpringApplication.run(So75681179Application.class, args);
    }

    @Bean
    public Supplier<Message<String>> supplier() {
        return () -> MessageBuilder.withPayload("foo").setHeader(KafkaHeaders.KEY, "my-foo".getBytes(StandardCharsets.UTF_8)).build();
    }

    @Bean
    public MessageChannel fooRecordChannel() {
        return new DirectChannel();
    }

    @Bean
    public IntegrationFlow integrationFlow() {
        return f -> f.channel("fooRecordChannel")
                .handle((payload, messageHeaders) -> {
                    System.out.println("Sent message: " + new String((byte[]) payload));
                    return payload;
                });
    }
}

and the configuration:

spring:
  cloud:
    function:
      definition: supplier
    stream:
      kafka:
        bindings:
          supplier-out-0:
            producer:
              recordMetadataChannel: fooRecordChannel