spring kafka 有多个生产者的代码示例吗？

Question

我有一个可能需要多个生产者的应用程序。我看到的所有代码示例似乎都支持单个生产者，在应用程序启动期间从应用程序读取配置。如果有多个生产者并且我们想传入不同的生产者配置，那么 Spring 是否有开箱即用的支持？或者在这种情况下我应该没有弹簧吗？

Answer 1

你将不得不在ProducerFactory下面创建两个不同的例子

    import org.apache.kafka.clients.producer.ProducerConfig;
    import org.apache.kafka.common.serialization.StringSerializer;
    import org.springframework.context.annotation.Bean;
    import org.springframework.context.annotation.Configuration;
    import org.springframework.kafka.core.DefaultKafkaProducerFactory;
    import org.springframework.kafka.core.KafkaTemplate;
    import org.springframework.kafka.core.ProducerFactory;

    import java.util.HashMap;

    @Configuration
    public class KafkaProducerConfig {


        @Bean
        public ProducerFactory<String, String> confluentProducerFactory() {

            HashMap<String, Object> configProps = new HashMap<String, Object>();
            configProps.put(
                    ProducerConfig.BOOTSTRAP_SERVERS_CONFIG,
                    "localhost:9092");
            configProps.put(
                    ProducerConfig.KEY_SERIALIZER_CLASS_CONFIG,
                    StringSerializer.class);
            configProps.put(
                    ProducerConfig.VALUE_SERIALIZER_CLASS_CONFIG,
                    StringSerializer.class);
            return new DefaultKafkaProducerFactory<>(configProps);
        }


        @Bean
        public ProducerFactory<String, String> cloudraProducerFactory() {

            HashMap<String, Object> configProps = new HashMap<String, Object>();
            configProps.put(
                    ProducerConfig.BOOTSTRAP_SERVERS_CONFIG,
                    "localhost:9094");
            configProps.put(
                    ProducerConfig.KEY_SERIALIZER_CLASS_CONFIG,
                    StringSerializer.class);
            configProps.put(
                    ProducerConfig.VALUE_SERIALIZER_CLASS_CONFIG,
                    StringSerializer.class);
            return new DefaultKafkaProducerFactory<>(configProps);
        }

        @Bean(name = "confluent")
        public KafkaTemplate<String, String> confluentKafkaTemplate() {
            return new KafkaTemplate<>(confluentProducerFactory());
        }

        @Bean(name = "cloudera")
        public KafkaTemplate<String, String> clouderaKafkaTemplate() {
            return new KafkaTemplate<>(cloudraProducerFactory());
        }

    }




public class ProducerExample {

    @Autowired
    @Qualifier("cloudera")
    private KafkaTemplate clouderaKafkaTemplate;


    @Autowired
    @Qualifier("confluent")
    private KafkaTemplate confluentKafkaTemplate;

    public void send() {
        confluentKafkaTemplate.send("TestConfluent", "hey there..confluent");
        clouderaKafkaTemplate.send("TestCloudEra","hey there.. cloudera");
    }

}

Answer 2

您可以创建多个Producer实例（KafkaTemplate）通过相同ProducerFactory。

如果您需要不同的 Kafka 配置，则需要不同的ProducerFactory实例。

Answer 3

如果您仍然想像往常一样保持配置application.yaml，并尽可能减少 Java 配置，您可以扩展KafkaProperties.Producer.

@Configuration
@ConfigurationProperties(prefix = "spring.kafka.producer-1")
@RequiredArgsConstructor
class FirstProducer extends KafkaProperties.Producer {
    private final KafkaProperties common;

    @Qualifier("producer-1")
    @Bean
    public ProducerFactory<?, ?> producerFactory() {
        final var conf = new HashMap<>(
            this.common.buildProducerProperties()
        );
        conf.putAll(this.buildProperties());
        return new DefaultKafkaProducerFactory<>(conf);

    }

    @Qualifier("producer-1")
    @Bean
    public KafkaTemplate<?, ?> kafkaTemplate() {
        return new KafkaTemplate<>(this.producerFactory());

    }
}

@Configuration
@ConfigurationProperties(prefix = "spring.kafka.producer-2")
@RequiredArgsConstructor
class SecondProducer extends KafkaProperties.Producer {
    private final KafkaProperties common;

    @Qualifier("producer-2")
    @Bean
    public ProducerFactory<?, ?> producerFactory() {
        final var conf = new HashMap<>(
            this.common.buildProducerProperties()
        );
        conf.putAll(this.buildProperties());
        return new DefaultKafkaProducerFactory<>(conf);

    }

    @Qualifier("producer-2")
    @Bean
    public KafkaTemplate<?, ?> kafkaTemplate() {
        return new KafkaTemplate<>(this.producerFactory());

    }
}