无法为多个消费者订阅 Spring Kafka Test 嵌入式 Kafka 代理

Question

我尝试让两个消费者订阅一个EmbeddedKafkaBroker。第一个成功了，第二个失败了。 @EmbeddedKafka 和 @ClassRule 代理都失败了。

@RunWith(SpringRunner.class)
@SpringBootTest
@EmbeddedKafka(topics = { "topic" })
public class AnnotationEmbeddedKafkaTest {

    @Autowired
    private EmbeddedKafkaBroker broker;

    @Test
    public void annotationEmbeddedKafkaTest() {
        Map<String, Object> consumerProps1 = KafkaTestUtils.consumerProps("testEmbedded", "false", broker);
        Consumer<String, String> consumer1 = new KafkaConsumer<>(consumerProps1);
        broker.consumeFromAnEmbeddedTopic(consumer1, "topic");
        System.out.println("consumer1 assignments=" + consumer1.assignment());

        Map<String, Object> consumerProps2 = KafkaTestUtils.consumerProps("testEmbedded", "false", broker);
        Consumer<String, String> consumer2 = new KafkaConsumer<>(consumerProps2);
        broker.consumeFromAnEmbeddedTopic(consumer2, "topic");
        System.out.println("consumer2 assignments=" + consumer2.assignment());
    }
}

@RunWith(SpringRunner.class)
@SpringBootTest
public class ClassRuleEmbeddedKafkaTest {

    @ClassRule
    public static EmbeddedKafkaRule embeddedKafkaRule = new EmbeddedKafkaRule(1, false, "topic");

    private EmbeddedKafkaBroker broker = embeddedKafkaRule.getEmbeddedKafka();

    @Test
    public void classRuleEmbeddedKafkaTest() {
        Map<String, Object> consumerProps1 = KafkaTestUtils.consumerProps("testEmbedded", "false", broker);
        Consumer<String, String> consumer1 = new KafkaConsumer<>(consumerProps1);
        broker.consumeFromAnEmbeddedTopic(consumer1, "topic");
        System.out.println("consumer1 assignments=" + consumer1.assignment());

        Map<String, Object> consumerProps2 = KafkaTestUtils.consumerProps("testEmbedded", "false", broker);
        Consumer<String, String> consumer2 = new KafkaConsumer<>(consumerProps2);
        broker.consumeFromAnEmbeddedTopic(consumer2, "topic");
        System.out.println("consumer2 assignments=" + consumer2.assignment());
    }
}

我希望这两个消费者可以订阅一个EmbeddedKafkaBroker。 Spring Kafka Test 可以吗？

我在这里复制了这个：https://github.com/yraydhitya/spring-kafka-test-multiple-consumers

Answer 1

如果您希望两个消费者都接收来自该主题的所有消息，您需要他们成为不同消费者组的一部分，例如：

Map<String, Object> consumerProps1 = KafkaTestUtils.consumerProps("testEmbedded1", "false", broker);

和

Map<String, Object> consumerProps2 = KafkaTestUtils.consumerProps("testEmbedded2", "false", broker);

否则每个消费者将被分配到主题的不同分区，并且由于您嵌入的 kafka 主题（默认情况下）只有一个分区，因此只会分配一个消费者。