目标解析器返回不存在的分区

Question

我正在使用 Spring-Kafka 来使用来自 Confluent Kafka 的消息，并且我正在使用 RetryTopicConfiguration Bean 来配置主题和退避策略。我的应用程序工作正常，但我在日志中看到很多警告日志，如下所示，我想知道我的配置是否不正确。

DeadLetterPublishingRecovererFactory : Destination resolver returned non-existent partition flow-events-retry-0-4, KafkaProducer will determine partition to use for this topic

配置代码

@Bean
    public KafkaTemplate kafkaTemplate() {
        return new KafkaTemplate<>(producerFactory());
    }

    @Bean
    public RetryTopicConfiguration myRetryableTopic(KafkaTemplate<String, Object> template) {
        return RetryTopicConfigurationBuilder
                .newInstance()
                .exponentialBackoff(BACKOFF_INITIAL_DELAY_10MINS, BACKOFF_EXPONENTIAL_MULTIPLIER_3, BACKOFF_MAX_DELAY_4HRS)
                .maxAttempts(5)
                .doNotAutoCreateRetryTopics()
                .setTopicSuffixingStrategy(TopicSuffixingStrategy.SUFFIX_WITH_INDEX_VALUE)
                .create(template);
    }

重试主题单独创建，分区为 1，复制因子为 3。

Answer 1

默认使用与原主题相同的分区；您可以通过覆盖 DeadLetterPublishingRecovererFactory @Bean:

来覆盖该行为

@Bean(RetryTopicInternalBeanNames.DEAD_LETTER_PUBLISHING_RECOVERER_FACTORY_BEAN_NAME)
DeadLetterPublishingRecovererFactory factory(DestinationTopicResolver resolver) {
    DeadLetterPublishingRecovererFactory factory = new DeadLetterPublishingRecovererFactory(resolver) {

        @Override
        protected TopicPartition resolveTopicPartition(ConsumerRecord<?, ?> cr, DestinationTopic nextDestination) {
            return new TopicPartition(nextDestination.getDestinationName(), -1); // Kafka Chooses
//          return new TopicPartition(nextDestination.getDestinationName(), 0);  // explict
        }

    };
    factory.setDeadLetterPublishingRecovererCustomizer(dlpr -> {
        // ...
    });
    return factory;
}

如您在此示例中所见，您也可以在此处自定义 DLPR 属性。

/**
 * Creates and returns the {@link TopicPartition}, where the original record should be forwarded.
 * By default, it will use the partition same as original record's partition, in the next destination topic.
 *
 * <p>{@link DeadLetterPublishingRecoverer#checkPartition} has logic to check whether that partition exists,
 * and if it doesn't it sets -1, to allow the Producer itself to assign a partition to the record.</p>
 *
 * <p>Subclasses can inherit from this method to override the implementation, if necessary.</p>
 *
 * @param cr The original {@link ConsumerRecord}, which is to be forwarded to DLT
 * @param nextDestination The next {@link DestinationTopic}, where the consumerRecord is to be forwarded
 * @return An instance of {@link TopicPartition}, specifying the topic and partition, where the cr is to be sent
 */
protected TopicPartition resolveTopicPartition(final ConsumerRecord<?, ?> cr, final DestinationTopic nextDestination) {
    return new TopicPartition(nextDestination.getDestinationName(), cr.partition());
}

目标解析器返回不存在的分区

Destination resolver returned non-existent partition

spring-kafka