Question

我正在定义一个类似于下面定义的消息监听器。消息是查询语句。消息按顺序推送到队列中，以便在推送到表时不会违反任何外键规则。当我将maxnumberofmessages设置为10时，我发现查询似乎是乱序执行的。但是，当我将其设置为1时，我没有看到任何问题。当我将maxnumberofmessages设置为高于1的值时，如何确保以与队列中相同的顺序读取消息？

@Bean
public SimpleMessageListenerContainer simpleMessageListenerContainer(AmazonSQSAsync amazonSQSAsync) {
    SimpleMessageListenerContainer simpleMessageListenerContainer = new SimpleMessageListenerContainer();
    simpleMessageListenerContainer.setAmazonSqs);
    simpleMessageListenerContainer.setMessageHandler(queueMessageHandler());
    simpleMessageListenerContainer.setMaxNumberOfMessages(10);
    return simpleMessageListenerContainer;
}


@SqsListener(value = "${sqs.url}", deletionPolicy = SqsMessageDeletionPolicy.ON_SUCCESS)
public void onMessage(String serviceData, @Header("MessageId") String messageId, @Header("ApproximateFirstReceiveTimestamp") String approximateFirstReceiveTimestamp) {
    repository.execute(serviceData);

}

修改后的代码

@Bean
public SimpleMessageListenerContainerFactory simpleMessageListenerContainerFactory() {
    SimpleMessageListenerContainerFactory msgListenerContainerFactory = new SimpleMessageListenerContainerFactory();
    msgListenerContainerFactory.setAmazonSqs(amazonSQSAsyncClient());
    msgListenerContainerFactory.setAutoStartup(false);
    msgListenerContainerFactory.setMaxNumberOfMessages(10);
    msgListenerContainerFactory.setTaskExecutor(threadPoolTaskExecutor());
    return msgListenerContainerFactory;
}


@Bean
public ThreadPoolTaskExecutor threadPoolTaskExecutor() {
    ThreadPoolTaskExecutor executor = new ThreadPoolTaskExecutor();
    executor.setCorePoolSize(1);
    executor.setMaxPoolSize(1);
    executor.setThreadNamePrefix("queueExecutor");
    executor.initialize();
    return executor;
}

@SqsListener(value = "${sqs.url}", deletionPolicy = SqsMessageDeletionPolicy.ON_SUCCESS)
public void onMessage(String serviceData, @Header("MessageId") String messageId, @Header("ApproximateFirstReceiveTimestamp") String approximateFirstReceiveTimestamp) {
    repository.execute(serviceData);

}

Answer 1

那是因为那里的逻辑就像：

   ReceiveMessageResult receiveMessageResult = getAmazonSqs().receiveMessage(this.queueAttributes.getReceiveMessageRequest());
   CountDownLatch messageBatchLatch = new CountDownLatch(receiveMessageResult.getMessages().size());
   for (Message message : receiveMessageResult.getMessages()) {
        if (isQueueRunning()) {
             MessageExecutor messageExecutor = new MessageExecutor(this.logicalQueueName, message, this.queueAttributes);
             getTaskExecutor().execute(new SignalExecutingRunnable(messageBatchLatch, messageExecutor));
        } else {
            messageBatchLatch.countDown();
        }
  }

注意getTaskExecutor().execute()。这就是你的消息如何转移到自己的线程以便执行。

您可以考虑将其重新配置为ThreadPoolTaskExecutor，其中池大小为1。并且所有消息都将在同一个线程上处理，因此将提供订单。

从sqs fifo队列获取消息后，以相同的顺序执行消息

1 个答案: