如何获得KafkaListener消费者

问题描述

我使用SpringBoot 2.0.4.RELEASE的Spring-Kafka。

并使用KafkaListener获取消息

现在我要重置我的组的偏移量

但我不知道如何获得群的消费者

    @KafkaListener(id="test",topics={"test"},groupId="group",containerFactory="batchContainerFactory")
    public String listenTopic33(List<ConsumerRecord<Integer, String>> record, Acknowledgment ack){
// do something

    }


    @Autowired
    KafkaListenerEndpointRegistry kafkaListenerEndpointRegistry;

    public void test() {

        MessageListenerContainer test3 = kafkaListenerEndpointRegistry.getListenerContainer("test3");
}

推荐答案

如果要在侦听器本身中查找使用者，只需向侦听器方法添加Consumer<?, ?> consumer参数。

请记住，容器可能已获取更多消息，因此您将在查找生效之前获得它们。您可以设置max.poll.records=1以避免这种情况。

您还可以向容器添加自定义RemainingRecordsErrorHandler，在侦听器中引发异常，错误处理程序将获得剩余的记录，而不是侦听器。

另请参阅Seeking to a Specific Offset。

void registerSeekCallback(ConsumerSeekCallback callback);

void onPartitionsAssigned(Map<TopicPartition, Long> assignments, ConsumerSeekCallback callback);

void onIdleContainer(Map<TopicPartition, Long> assignments, ConsumerSeekCallback callback);

void seek(String topic, int partition, long offset);

void seekToBeginning(String topic, int partition);

void seekToEnd(String topic, int partition);

这里有一个例子；我们跟踪每个主题/分区的回调...

@SpringBootApplication
public class So56584233Application {

    public static void main(String[] args) {
        SpringApplication.run(So56584233Application.class, args);
    }

    @Bean
    public ApplicationRunner runner(Listener listener, KafkaTemplate<String, String> template) {
        return args -> {
            IntStream.range(0, 10).forEach(i -> template.send(new ProducerRecord<>("so56584233", i % 3, "foo", "bar")));
            while (true) {
                System.in.read();
                listener.seekToStart();
            }
        };
    }

    @Bean
    public NewTopic topic() {
        return new NewTopic("so56584233", 3, (short) 1);
    }

}

@Component
class Listener implements ConsumerSeekAware {


    private static final Logger logger = LoggerFactory.getLogger(Listener.class);


    private final Map<TopicPartition, ConsumerSeekCallback> callbacks = new ConcurrentHashMap<>();

    private static final ThreadLocal<ConsumerSeekCallback> callbackForThread = new ThreadLocal<>();

    @Override
    public void registerSeekCallback(ConsumerSeekCallback callback) {
        callbackForThread.set(callback);
    }

    @Override
    public void onPartitionsAssigned(Map<TopicPartition, Long> assignments, ConsumerSeekCallback callback) {
        assignments.keySet().forEach(tp -> this.callbacks.put(tp, callbackForThread.get()));
    }

    @Override
    public void onIdleContainer(Map<TopicPartition, Long> assignments, ConsumerSeekCallback callback) {
    }

    @KafkaListener(id = "so56584233", topics = "so56584233", concurrency = "3")
    public void listen(ConsumerRecord<String, String> in) {
        logger.info(in.toString());
    }

    public void seekToStart() {
        this.callbacks.forEach((tp, callback) -> callback.seekToBeginning(tp.topic(), tp.partition()));
    }

}

这篇关于如何获得KafkaListener消费者的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持！