Question

我正在使用Kafka生成器10.2.1创建主题并写入主题，当我创建主题时出现以下错误，但主题已创建：

java.util.concurrent.ExecutionException: org.apache.kafka.common.errors.TimeoutException: Failed to update metadata after 60000 ms.
    at org.apache.kafka.clients.producer.KafkaProducer$FutureFailure.<init>(KafkaProducer.java:774)
    at org.apache.kafka.clients.producer.KafkaProducer.doSend(KafkaProducer.java:494)
    at org.apache.kafka.clients.producer.KafkaProducer.send(KafkaProducer.java:440)
    at org.apache.kafka.clients.producer.KafkaProducer.send(KafkaProducer.java:360)
    at kafka.AvroProducer.produce(AvroProducer.java:47)
    at samples.TestMqttSource.messageReceived(TestMqttSource.java:89)
    at mqtt.JsonConsumer.messageArrived(JsonConsumer.java:132)
    at org.eclipse.paho.client.mqttv3.internal.CommsCallback.deliverMessage(CommsCallback.java:477)
    at org.eclipse.paho.client.mqttv3.internal.CommsCallback.handleMessage(CommsCallback.java:380)
    at org.eclipse.paho.client.mqttv3.internal.CommsCallback.run(CommsCallback.java:184)
    at java.lang.Thread.run(Thread.java:748)
Caused by: org.apache.kafka.common.errors.TimeoutException: Failed to update metadata after 60000 ms.
msg org.apache.kafka.common.errors.TimeoutException: Failed to update metadata after 60000 ms.
loc org.apache.kafka.common.errors.TimeoutException: Failed to update metadata after 60000 ms.
cause org.apache.kafka.common.errors.TimeoutException: Failed to update metadata after 60000 ms.
excep java.util.concurrent.ExecutionException: org.apache.kafka.common.errors.TimeoutException: Failed to update metadata after 60000 ms.

非常感谢所有建议。

Answer 1

您不能使用KafkaProducer创建主题（所以我不太确定您是如何设法创建主题的，除非您之前通过其他方法（例如kafka admin shell脚本）执行此操作） / em>的。而是使用Kafka库提供的AdminUtils。

我最近达到了你所要求的两个要求，你会惊讶地发现它是多么容易。下面是一个简单的代码示例，向您展示如何通过AdminUtils创建主题，以及如何写入主题。

class Foo { private String TOPIC = "testingTopic"; private int NUM_OF_PARTITIONS = 10; private int REPLICATION_FACTOR = 1; public Foo() { ZkClient zkClient = new ZkClient( "localhost:2181", 15000, 10000, ZKStringSerializer$.MODULE$ ); ZkUtils zkUtils = new ZkUtils( zkClient, new ZkConnection( "localhost:2181" ), false); if ( !AdminUtils.topicExists(zkUtils, TOPIC) ) { try { AdminUtils.createTopic(zkUtils, TOPIC, NUM_OF_PARTITIONS, REPLICATION_FACTOR, new Properties(), Enforced$.MODULE$); Properties producerConfig = new Properties(); producerConfig.put(ProducerConfig.BOOTSTRAP_SERVER_CONFIG, "localhost:9092"); producerConfig.put(ProducerConfig.KEY_SERIALIZER_CLASS_CONFIG, "org.apache.kafka.common.serialization.ByteArraySerializer"); producerConfig.put(ProducerConfig.VALUE_SERIALIZER_CLASS_CONFIG, "org.apache.kafka.common.serialization.StringSerializer"); KafkaProducer<String, String> producer = new KafkaProducer<>(producerConfig); // This is just to show you how to write but you could be more elaborate int i = 0; while ( i < 11 ) { ProducerRecord<String, String> rec = new ProducerRecord<>(TOPIC, ("This is line number " + i)); producer.send(rec); i++; } producer.closer(); } catch ( AdminOperationException aoe ) { aoe.printStackTrace(); } } } }

请记住，如果要删除主题，默认情况下会禁用此设置。启动Kafka 时使用的配置文件（默认为$ {kafka_home} /config/server.properties），如果该行尚不存在，则添加以下行并设置为false或注释出：

delete.topic.enabled=true

然后，您必须重新启动服务器，并可以通过Java或提供的命令行工具删除主题。

<强> NB

当您完成生产者/消费者时，关闭生产者/消费者总是一个好主意，如代码示例所示。

在创建主题时在Kafka生成器中获取错误，但主题是在Kafka服务器上创建的

1 个答案: