MessageProperties#correlationIdString returns an empty value when correlation ID is set

[HermanCho]

the scene : (needs)

I set the id in the message. Then I send it . And I hope to get the id after I receive the message.

I have read the source code and success finishing my needs , I just want to report that "bug".

due to the limited English ability，I hope I expressed clear.If anything wrong,please just ask me.
Or if the bug has already solved, please tell me the version of jar.Thanks.

---

envenviroment：

springboot 1.5.8.RELEASE + amqp-client 4.0.3(jar)

(I have already use the latest version , but the jar is still the same)

<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-amqp</artifactId>
    <version>2.3.2.RELEASE</version>
</dependency>

api : RabbitTemplate.class + convertAndSend() method

---

I set the correlationData into BasicProperties.correlationId.

However, when I received the message , I can't get the correlationId through messageProperties.getCorrelationIdString() (the result is null) .

But I can get the correct answer through

byte[] bytes = messageProperties.getCorrelationId() ，then I just need to transfer it into String.class。

the problem is : the variable, byte[] correlationId , is deprecated.

I guess it should be the problem of broker，after updating the client-code , your team forget to update the method,which broker handle the message.

---

here is my Code :

• the configuration of rabbitTemplate

@Bean
    @Scope(ConfigurableBeanFactory.SCOPE_PROTOTYPE)
    public RabbitTemplate rabbitTemplate(ConnectionFactory connectionFactory) {
        RabbitTemplate rabbitTemplate = new RabbitTemplate(connectionFactory);
        rabbitTemplate.setBeforePublishPostProcessors(correlationIdProcessor());
        rabbitTemplate.setMessagePropertiesConverter(defaultMessagePropertiesConverter());
        return rabbitTemplate;
    }


    @Bean
    public MessagePostProcessor correlationIdProcessor(){
        MessagePostProcessor messagePostProcessor = new CorrelationAwareMessagePostProcessor() {
            @Override
            public Message postProcessMessage(Message message, Correlation correlation) {
                MessageProperties messageProperties = message.getMessageProperties();
                if(correlation instanceof CorrelationData){
                    String correlationId = ((CorrelationData) correlation).getId();
                    messageProperties.setCorrelationIdString(correlationId);
                }
                return message;
            }

            @Override
            public Message postProcessMessage(Message message) throws AmqpException {
                return message;
            }
        };
        return messagePostProcessor;
    }


    @Bean
    public MessagePropertiesConverter defaultMessagePropertiesConverter() {
        DefaultMessagePropertiesConverter messagePropertiesConverter 
            = new DefaultMessagePropertiesConverter();
     messagePropertiesConverter
         .setCorrelationIdPolicy(DefaultMessagePropertiesConverter.CorrelationIdPolicy.STRING);
        return messagePropertiesConverter;
    }

• producer

public void sendMessage(String msg) {
        CorrelationData correlationData = new CorrelationData();
        String uuid = UUID.randomUUID().toString();
        correlationData.setId(uuid);
        System.out.println("set the id: " + uuid);
        System.out.println("send the message");
        rabbitTemplate.convertAndSend(MQConfig.MIAOSHA_EXCHANGE, MQConfig.MIAOSHA_ROUTING_KEY,
                this.buildMessage(msg, correlationData.getId()), correlationData);
}

• consumer

  @RabbitListener(queues = MQConfig.MIAOSHA_QUEUE)
      @RabbitHandler
      public void receiveMessage(String msg, Channel channel, Message messages) {
          System.out.println("receive the message");
          MessageProperties messageProperties = messages.getMessageProperties();
          messageProperties.getCorrelationIdString();
          byte[] bytes = messageProperties.getCorrelationId();
          if (bytes != null) {
              String id = new String(bytes);
              System.out.println("receive the id: " + id);
          } else {
              System.out.println("the id is empty");
          }
  
          String correlationIdString = messageProperties.getCorrelationIdString();
          System.out.println("the correlationIdString is empty?" + StringUtils.isEmpty(correlationIdString));
  
          System.out.println(messageProperties.toString());
      }

the terminal output:

here is the detailed messageProperties.toString()

MessageProperties 
    [headers={}, timestamp=null, messageId=null, userId=null, receivedUserId=null, appId=null, clusterId=null, type=null, 
     
     correlationId=[49, 48, 53, 101, 98, 97, 55, 55, 45, 50, 56, 98, 54, 45, 52, 56, 56, 51, 45, 97, 49, 57, 102, 45, 50, 48, 54, 56, 53, 48, 54, 99, 57, 98, 49, 97], 
     correlationIdString=null, 
     
     replyTo=null, contentType=text/plain, contentEncoding=UTF-8, contentLength=0, deliveryMode=null, receivedDeliveryMode=PERSISTENT, expiration=null, priority=0, redelivered=false, receivedExchange=miaosha.directExchange, receivedRoutingKey=secKill, receivedDelay=null, deliveryTag=1, messageCount=0, consumerTag=amq.ctag-5vRvXa8L8E38HZXD2SDbbQ, consumerQueue=miaosha.queue]

you can see that correlationIdString is null when correlationId is not null.

and here is my github address(if need?) : https://github.com/HermanCho/seckill

[michaelklishin]

getCorrelationIdString is not something defined in the Java client and most certainly this is no evidence of a server bug.

Please ask a question on Spring forum, e.g. StackOverflow tagged with spring-amqp.

[HermanCho]

OK,Thanks