How to set per message TTL with RabbitTemplate?

Question

I'm using spring-boot with rabbitMQ and I'm wondering if I can use per message TTL using RabbitTemplate. So far I have :

@Autowired
   private RabbitTemplate rabbit;

   public void produce() {

      rabbit.convertAndSend("My.Queue", routingKey, message);
   }

Answer 1

You can create MessagePostProcessor and use it in you rabbitTemplate :

final String message = "message";
final MessagePostProcessor messagePostProcessor = new MyMessagePostProcessor(10000);
rabbitTemplate.convertAndSend("my.queue", "routingKey", message, messagePostProcessor);

This will catch you message, apply changes and send further.

public class MyMessagePostProcessor implements MessagePostProcessor {

    private final Integer ttl;

    public MyMessagePostProcessor(final Integer ttl) {
        this.ttl = ttl;
    }

    @Override
    public Message postProcessMessage(final Message message) throws AmqpException {
        message.getMessageProperties().getHeaders().put("expiration", ttl.toString());
        return message;
    }
}

Answer 2

Just to have a little workaround:

@Autowired
   private RabbitTemplate   rabbit;

   @Autowired
   private MessageConverter jsonMessageConverter;

   public void produce() {

      rabbit.setExchange("My.Exchange");
      rabbit.setRoutingKey("R.K");
      rabbit.setMessageConverter(jsonMessageConverter);
      MessageProperties props = new MessageProperties();
      props.setExpiration(Long.toString(expiration));
      Message toSend = new Message(message.toString().getBytes(), props);
      rabbit.send(toSend);
   }

Answer 3

如果您要使用MessagePostProcessor解决方案，您应该向消息添加属性而不是标题。

message.getMessageProperties().setExpiration(ttl.toString());