11.5. MicroProfile Reactive Messaging リファレンス

@Outgoing("to")
public int send() {
   int i = // Randomly generated...
   return i;
}

@Incoming("from")
public void receive(int i) {
   // Process payload
}

@Path("/")
@ApplicationScoped
class MyBean {
    @Inject @Channel("my-stream")
    Emitter<String> emitter; 

    Publisher<String> dest;

    public MyBean() { 

    }

    @Inject
    public MyBean(@Channel("my-stream") Publisher<String> dest) {
        this.dest = subscribeAndAllowMultipleSubscriptions(dest);
    }

    private Publisher subscribeAndAllowMultipleSubscriptions(Publisher delegate) {
    } 

    @POST
    public PublisherBuilder<String> publish(@FormParam("value") String value) {
        return emitter.send(value);
    }

    @GET
    public Publisher poll() {
        return dest;
    }

    @PreDestroy
    public void close() { 

    }
}

@Inject
@Channel("from-user")
Emitter<Integer> emitter;

@Incoming("from-user")
@Outgoing("to-kafka")
public Message<Integer> send(Message<Integer> msg) {
    // Set the key in the metadata
    OutgoingKafkaRecordMetadata<String> md =
            OutgoingKafkaRecordMetadata.<String>builder()
                .withKey("KEY-" + i)
                .build();
    // Note that Message is immutable so the copy returned by this method
    // call is not the same as the parameter to the method
    return KafkaMetadataUtil.writeOutgoingKafkaMetadata(msg, md);
}

@Incoming("from-kafka")
public CompletionStage<Void> receive(Message<Integer> msg) {
    IncomingKafkaRecordMetadata<String, Integer> metadata =
        KafkaMetadataUtil.readIncomingKafkaMetadata(msg).get();

    // We can now read the Kafka record key
    String key = metadata.getKey();

    // When using the Message wrapper around the payload we need to explicitly ack
    // them
    return msg.ack();
}

kafka.bootstrap.servers=kafka:9092

mp.messaging.outgoing.to-kafka.connector=smallrye-kafka
mp.messaging.outgoing.to-kafka.topic=some-topic
mp.messaging.outgoing.to-kafka.value.serializer=org.apache.kafka.common.serialization.IntegerSerializer
mp.messaging.outgoing.to-kafka.key.serializer=org.apache.kafka.common.serialization.StringSerializer

mp.messaging.incoming.from-kafka.connector=smallrye-kafka
mp.messaging.incoming.from-kafka.topic=some-topic
mp.messaging.incoming.from-kafka.value.deserializer=org.apache.kafka.common.serialization.IntegerDeserializer
mp.messaging.incoming.from-kafka.key.deserializer=org.apache.kafka.common.serialization.StringDeserializer

kafka.bootstrap.servers=kafka:9092

mp.messaging.outgoing.to.connector=smallrye-kafka
mp.messaging.outgoing.to.topic=my-topic
mp.messaging.outgoing.to.value.serializer=org.apache.kafka.common.serialization.IntegerSerializer

mp.messaging.incoming.from.connector=smallrye-kafka
mp.messaging.incoming.from.topic=my-topic
mp.messaging.incoming.from.value.deserializer=org.apache.kafka.common.serialization.IntegerDeserializer

@Outgoing("to")
public int send() {
    int i = // Randomly generated...
    return i;
}

@Incoming("from")
public void receive(int i) {
    // Process payload
}