Question

如何将JsonDeserializer添加到我的Kafka用户。我现在收到一个Json字符串，并希望将其转换为数据类对象。

这是我的消费者：

ConsumerConfig：

@EnableKafka
@Configuration
class KafkaConsumerConfig {
@Value("\${kafka.host:localhost}")
private val host: String? = null

@Value("\${kafka.port:9092}")
private val port: Int = 0

@Bean
fun userConsumerConfigs(): ConsumerFactory<String, String> {
    val props = HashMap<String, Any>()
    props[ConsumerConfig.BOOTSTRAP_SERVERS_CONFIG] = "$host:$port"
    props[ConsumerConfig.KEY_DESERIALIZER_CLASS_CONFIG] = StringDeserializer::class.java
    props[ConsumerConfig.VALUE_DESERIALIZER_CLASS_CONFIG] = StringDeserializer::class.java
    props[ConsumerConfig.GROUP_ID_CONFIG] = "helloworld"
    val mapper = ObjectMapper()
    return DefaultKafkaConsumerFactory(props, StringDeserializer(), StringDeserializer())

    //return props
}


@Bean
fun kafkaListenerContainerFactory(): 
KafkaListenerContainerFactory<ConcurrentMessageListenerContainer<String, 
String>> {
    val factory = ConcurrentKafkaListenerContainerFactory<String, String>()
    factory.consumerFactory = userConsumerConfigs()
    return factory
}

@Bean
fun kafkaConsumer(): Consumerz {
    return Consumerz()
}

companion object {
    const val TOPIC = "test"
}
}

消费者：

class Consumerz {
@KafkaListener(topics = ["usertest"])
fun receive(message: String) {
     LOGGER.info("Received payload= $message")

}

companion object {
    private val LOGGER = LoggerFactory.getLogger(Consumerz::class.java)
}
}

我目前仅使用StringDeserializer。在这种情况下，我该如何实现JsonDeserializer。

当前输出为：Received payload= { "firstName": "Jack", "lastName" : "Adam" }

谢谢。

@这是一个 Spring 项目。

Answer 1

您可以按以下方式直接使用org.springframework.kafka.support.serializer.JsonDeserializer.class

props.put(ConsumerConfig.VALUE_DESERIALIZER_CLASS_CONFIG, JsonDeserializer.class);

因此，使用者配置为：

private ConsumerFactory<String, MyDomainModel> myMessageFactory() {
    Map<String, Object> props = new HashMap<>();
    props.put(ConsumerConfig.BOOTSTRAP_SERVERS_CONFIG, SERVERS);
    props.put(ConsumerConfig.GROUP_ID_CONFIG, "KAPP");
    props.put(ConsumerConfig.VALUE_DESERIALIZER_CLASS_CONFIG, JsonDeserializer.class);

    return new DefaultKafkaConsumerFactory<>(props, new StringDeserializer(), new JsonDeserializer<>(MyDomainModel.class));
}

@Bean
public ConcurrentKafkaListenerContainerFactory<String, MyDomainModel> myMessageListenerContainerFactory() {
    ConcurrentKafkaListenerContainerFactory<String, MyDomainModel> factory = new ConcurrentKafkaListenerContainerFactory<>();
    factory.setConsumerFactory(myMessageFactory());
    return factory;
}

如何在Kotlin中将JsonDeserializer添加到Kafka消费者？

1 个答案: