Pubblicazione di messaggi da Apache Kafka

Pubblicare messaggi in un argomento Pub/Sub Lite utilizzando uno shim per l'API Kafka Producer

Esempio di codice

Java

Per autenticarti a Pub/Sub Lite, configura le Credenziali predefinite dell'applicazione. Per ulteriori informazioni, consulta Configurare l'autenticazione per un ambiente di sviluppo locale.

import com.google.cloud.pubsublite.CloudRegion;
import com.google.cloud.pubsublite.CloudZone;
import com.google.cloud.pubsublite.ProjectNumber;
import com.google.cloud.pubsublite.TopicName;
import com.google.cloud.pubsublite.TopicPath;
import com.google.cloud.pubsublite.kafka.ProducerSettings;
import java.util.ArrayList;
import java.util.List;
import java.util.concurrent.ExecutionException;
import java.util.concurrent.Future;
import org.apache.kafka.clients.producer.Producer;
import org.apache.kafka.clients.producer.ProducerRecord;
import org.apache.kafka.clients.producer.RecordMetadata;

public class ProducerExample {

  public static void main(String... args) throws Exception {
    // TODO(developer): Replace these variables before running the sample.
    String cloudRegion = "your-cloud-region";
    char zoneId = 'b';
    // Use an existing Pub/Sub Lite topic.
    String topicId = "your-topic-id";
    // Using the project number is required for constructing a Pub/Sub Lite
    // topic path that the Kafka producer can use.
    long projectNumber = Long.parseLong("123456789");

    producerExample(cloudRegion, zoneId, projectNumber, topicId);
  }

  public static void producerExample(
      String cloudRegion, char zoneId, long projectNumber, String topicId)
      throws InterruptedException, ExecutionException {
    TopicPath topicPath =
        TopicPath.newBuilder()
            .setLocation(CloudZone.of(CloudRegion.of(cloudRegion), zoneId))
            .setProject(ProjectNumber.of(projectNumber))
            .setName(TopicName.of(topicId))
            .build();

    ProducerSettings producerSettings =
        ProducerSettings.newBuilder().setTopicPath(topicPath).build();

    List<Future<RecordMetadata>> futures = new ArrayList<>();
    try (Producer<byte[], byte[]> producer = producerSettings.instantiate()) {
      for (long i = 0L; i < 10L; i++) {
        String key = "demo";
        Future<RecordMetadata> future =
            producer.send(
                new ProducerRecord(
                    topicPath.toString(), key.getBytes(), ("message-" + i).getBytes()));
        futures.add(future);
      }
      for (Future<RecordMetadata> future : futures) {
        RecordMetadata meta = future.get();
        System.out.println(meta.offset());
      }
    }
    System.out.printf("Published 10 messages to %s%n", topicPath.toString());
  }
}

Passaggi successivi

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