java - 永远的卡夫卡消费者民意调查

Question

我想弄清楚为什么 consumer.poll 在我的测试中永远挂起。

在 Debug模式下，消费者似乎无法在无限的 while 循环中找到组协调器。

我的测试代码:

final String BROKER_PORT = "9092";
final String HOST = "localhost";
final String BOOTSTRAP_SERVERS = HOST + ":" + BROKER_PORT;
final String ZK_PORT = "2181";
final Integer ZK_PORT_INT = Integer.valueOf(ZK_PORT);
final String ZK_HOST = HOST + ":" + ZK_PORT;

    final String topic = "test-topic-10";

    //start zookeeper
    String path = new File(".").getCanonicalPath();
    zookeeper = new TestingServer(ZK_PORT_INT, new File(path));
    Thread.sleep(5_000);

    //start broker
    final File logDirectory = Files.createTempDir();
    logDirectory.deleteOnExit();
    final Properties p = new Properties();
    p.put("zookeeper.connect", zookeeper.getConnectString());
    p.put("broker.id", "1");
    p.put("num.partitions", "1");
    p.put("host.name", HOST);
    p.put("port", BROKER_PORT);
    p.put("log.dir", logDirectory.getAbsolutePath());
    p.put("auto.create.topics.enable", "true");
    p.put("delete.topic.enable", "true");
    p.put("log.cleaner.dedupe.buffer.size", 2 * 1024 * 1024L + "");
    new KafkaServerStartable(new KafkaConfig(p)).startup();

    //send one record with producer
    Properties props = new Properties();
    props.put(ProducerConfig.BOOTSTRAP_SERVERS_CONFIG, BOOTSTRAP_SERVERS);
    props.put(ProducerConfig.KEY_SERIALIZER_CLASS_CONFIG, StringSerializer.class.getName());
    props.put(ProducerConfig.VALUE_SERIALIZER_CLASS_CONFIG, StringSerializer.class.getName());
    KafkaProducer<String, String> producer = new KafkaProducer<>(props);
    producer.send(new ProducerRecord<>(topic, "key", "val"));

    // Try to poll record with consumer
    Properties properties = new Properties();
    properties.put(ConsumerConfig.BOOTSTRAP_SERVERS_CONFIG, BOOTSTRAP_SERVERS);
    properties.put(ConsumerConfig.KEY_DESERIALIZER_CLASS_CONFIG, StringDeserializer.class.getName());
    properties.put(ConsumerConfig.VALUE_DESERIALIZER_CLASS_CONFIG, StringDeserializer.class.getName());
    KafkaConsumer<String, String> consumer = new KafkaConsumer<>(properties);
    consumer.subscribe(Collections.singletonList(topic));
    System.out.println("POLL!");
    ConsumerRecords<String, String> records = consumer.poll(Duration.ofDays(1));
    System.out.println(records);

Answer 1

将以下属性添加到您的消费者并重试

 properties.put(ConsumerConfig.AUTO_OFFSET_RESET_CONFIG, "earliest");