Filter messages before deserialization based on headers

问题

Sometimes messages can be filtered out before the deserialization based on header values . Are there any existing patterns for this scenario using spring kafka. I am thinking implementing similar to ErrorHandlingDeserializer in addition to delegate take filter predicate also as property. Any suggestions? thanks.

回答1:

Yes, you can use the same technique used by the ErrorHandlingDeserializer2 (which replaces the ErrorHandlingDeserializer) to return a "marker" object instead of doing the deserialization, then add a RecordFilterStrategy, that filters records with such objects, to the listener (container factory when using @KafkaListener or use a filtering adapter for an explicit listener).

EDIT

Spring Boot and adding a filter...

@Bean
public ConcurrentKafkaListenerContainerFactory<?, ?> kafkaListenerContainerFactory(
        ConcurrentKafkaListenerContainerFactoryConfigurer configurer,
        ConsumerFactory<Object, Object> kafkaConsumerFactory) {
    ConcurrentKafkaListenerContainerFactory<Object, Object> factory = new ConcurrentKafkaListenerContainerFactory<>();
    configurer.configure(factory, kafkaConsumerFactory);
    kafkaConsumerFactory.setsetRecordFilterStrategy(myFilter());
    return factory;
}

来源：https://stackoverflow.com/questions/53843328/filter-messages-before-deserialization-based-on-headers