Spring AMQP：将消息处理器添加到自动配置的“RabbitTemplate”

Question

我正在尝试调用 RabbitTemplate#addBeforePublishPostProcessors 和 RabbitTemplate#addAfterReceivePostProcessors 而不会过多地干扰 Spring 的自动配置。

我正在尝试执行此操作，但我的 MessagePostProcessor 没有触发（我在发布的消息中没有看到“test_header”）。

  @EventListener
  void test(ApplicationPreparedEvent event) {
    ConfigurableApplicationContext applicationContext = event.getApplicationContext();
    RabbitTemplate rabbitTemplate = applicationContext.getBean(RabbitTemplate.class);
    rabbitTemplate.addBeforePublishPostProcessors(new MessagePostProcessor() {
      @Override
      public Message postProcessMessage(Message message) throws AmqpException {
        message.getMessageProperties().setHeader("test_header", "test_header_value");
        return message;
      }
    });
  }

什么地方适合做这个？

我也试过收听ApplicationStartedEvent。

更新：

根据 Gary 的建议，在我的 @Configuration 课程中添加了这个 bean：

  @Bean
  public static BeanPostProcessor rabbitTemplatePostProcessor() {
    return new BeanPostProcessor() {
      @Override
      public Object postProcessAfterInitialization(Object bean, String beanName) throws BeansException {
        if(bean instanceof RabbitTemplate) {
          RabbitTemplate rabbitTemplate = (RabbitTemplate) bean;

          rabbitTemplate.addBeforePublishPostProcessors(m -> {
            m.getMessageProperties()
              .setHeader(MESSAGE_PUBLISHED_TIME, currentTimeMillis());
            return m;
          });

          rabbitTemplate.addAfterReceivePostProcessors(m -> {
            m.getMessageProperties().setHeader(MESSAGE_RECEIVED_TIME, currentTimeMillis());
            return m;
          });
        }
        return bean;
      }
    };
  }

如果您正在使用@RabbitListener 和@SendTo，如果您正在寻找有关如何执行此操作的答案的任何人，请参阅 Gary 对其答案的编辑。

Answer 1

使用BeanPostProcessor。

@SpringBootApplication
public class So56155062Application {

    public static void main(String[] args) {
        SpringApplication.run(So56155062Application.class, args);
    }

    @Bean
    public static BeanPostProcessor bpp() {
        return new BeanPostProcessor() {

            @Override
            public Object postProcessAfterInitialization(Object bean, String beanName) throws BeansException {
                if (bean instanceof RabbitTemplate) {
                    ((RabbitTemplate) bean).setBeforePublishPostProcessors(m -> {
                        m.getMessageProperties().setHeader("foo", "baz");
                        return m;
                    });
                }
                return bean;
            }

        };

    }

    @Bean
    public ApplicationRunner runner(RabbitTemplate template) {
        return args -> template.convertAndSend("foo", "bar");
    }

    @RabbitListener(queues = "foo")
    public void listen(String in, @Header("foo") String header) {
        System.out.println(in + header);
    }

}

注意static 修饰符

编辑

模板不用于回复；后处理器转而使用容器工厂。

@SpringBootApplication
public class So56155062Application {

    public static void main(String[] args) {
        SpringApplication.run(So56155062Application.class, args);
    }

    @Bean
    public static BeanPostProcessor bpp() {
        return new BeanPostProcessor() {

            @Override
            public Object postProcessAfterInitialization(Object bean, String beanName) throws BeansException {
                if (bean instanceof RabbitTemplate) {
                    ((RabbitTemplate) bean).setBeforePublishPostProcessors(m -> {
                        m.getMessageProperties().setHeader("foo", "baz");
                        m.getMessageProperties().setReplyTo("bar");
                        System.out.println("Adding header to outgoing message with payload: " + new String(m.getBody()));
                        return m;
                    });
                }
                else if (bean instanceof AbstractRabbitListenerContainerFactory) {
                    ((AbstractRabbitListenerContainerFactory<?>) bean).setAfterReceivePostProcessors(m -> {
                        m.getMessageProperties().setHeader("qux", "fiz");
                        System.out.println("Adding header to incoming message with payload: " + new String(m.getBody()));
                        return m;
                    });
                    ((AbstractRabbitListenerContainerFactory<?>) bean).setBeforeSendReplyPostProcessors(m -> {
                        m.getMessageProperties().setHeader("foo", "baz");
                        m.getMessageProperties().setReplyTo("bar");
                        System.out.println(
                                "Adding header to outgoing reply message with payload: " + new String(m.getBody()));
                        return m;
                    });
                }
                return bean;
            }

        };

    }

    @Bean
    public ApplicationRunner runner(RabbitTemplate template) {
        return args -> template.convertAndSend("foo", "bar");
    }

    @RabbitListener(queues = "foo")
    @SendTo
    public String listen1(String in, @Header("foo") String header) {
        System.out.println(in + header);
        return in.toUpperCase();
    }

    @RabbitListener(queues = "bar")
    public void listen2(String in) {
        System.out.println(in);
    }

}

和

Adding header to outgoing message with payload: bar
Adding header to incoming message with payload: bar
barbaz
Adding header to outgoing reply message with payload: BAR
Adding header to incoming message with payload: BAR
BAR