Question

我正在尝试使用@SentTo批注将返回值发送到RabbitMQ交易所，如此处的文档所述：https://docs.spring.io/spring-amqp/reference/htmlsingle/#async-annotation-driven-reply

如果我需要设置Herader，则文档说要返回Message<OrderStatus>并使用MessageBuilder。

但是，我需要设置correlationId消息属性，而MessageBuilder没有办法让我设置属性，只能设置标头。

如何使用@SentTo注释复制我目前在这里所做的事情？

amqpTemplate.convertAndSend(
  amqpRoutingKey,
  orderStatus,
  message -> {
    message.getMessageProperties().setCorrelationId(orderStatus.getCorrelationId().toString());
    return message;
  }
);

谢谢！

Answer 1

有这个API：

/**
 * Makes this builder's properties builder use a reference to properties.
 * @param properties The properties.
 * @return this.
 */
public MessageBuilder andProperties(MessageProperties properties) {

或者您也可以得到该MessageBuilder的结果，然后真正调用message.getMessageProperties().setCorrelationId()。

更新

好吧，AbstractRabbitListenerContainerFactory中甚至还有刚刚发布的Spring AMQP的这个API：

/**
 * Set post processors that will be applied before sending replies.
 * @param beforeSendReplyPostProcessors the post processors.
 * @since 2.0.3
 */
public void setBeforeSendReplyPostProcessors(MessagePostProcessor... beforeSendReplyPostProcessors) {

UPDATE2

如果您坚持使用org.springframework.messaging.support.MessageBuilder，则应在该消息中设置一个AmqpHeaders.CORRELATION_ID标头，并将其正确映射到CorrelationId。但是，查看代码不需要这样做：

/**
 * Post-process the given response message before it will be sent.
 * <p>
 * The default implementation sets the response's correlation id to the request message's correlation id, if any;
 * otherwise to the request message id.
 * @param request the original incoming Rabbit message
 * @param response the outgoing Rabbit message about to be sent
 */
protected void postProcessResponse(Message request, Message response) {
    String correlation = request.getMessageProperties().getCorrelationId();

    if (correlation == null) {
        String messageId = request.getMessageProperties().getMessageId();
        if (messageId != null) {
            correlation = messageId;
        }
    }
    response.getMessageProperties().setCorrelationId(correlation);
}

使用Spring AMQP批注驱动的回复（@SentTo）发布流程消息

1 个答案: