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 首先，Amazon SQS是一个伪队列，可保证消息的可用性，但不保证FIFO时序的顺序。 如果您希望以这种方式工作，您必须在您的应用中实施排序逻辑。 
 
 回到你的问题，SQS必须在你的应用程序中进行轮询，以检查是否有新消息可用。 我使用setInterval()在应用程序中实现了这一点。 我会轮询队列中的物品，如果找不到物品，我会延迟下一次呼叫，并且如果发现某些物品，下一次呼叫将立即绕过setInterval() 。 这显然是一个非常原始的实施，你可以看看替代品。 在SQS中找到新项目时，服务器上的子进程如何处理NodeJS应用程序？ 我想你可以在不使用NodeJS的情况下在BASH中作为一个观察者来实现子进程。 如果已经有一个模块，你也可以查看npm模块。 
 
 简而言之，您可以通过多种方式进行轮询，但如果您正在使用Amazon SQS，则必须以某种方式进行轮询。 
 
 我不确定这一点，但如果您希望收到物品通知，您可能需要查看Amazon SNS。 

For a start, Amazon SQS is a pseudo queue that guarantees availability of messages but not their sequence in FIFO fashion. You have to implement sequencing logic into your app if you want it to work that way.
 
Coming back to your question, SQS has to be polled within your app to check if there are new messages available. I implemented this in an app using setInterval(). I would poll the queue for items and if no items were found, I would delay the next call and in case some items were found, the next call would be immediate bypassing the setInterval(). This is obviously a very raw implementation and you can look into alternatives. How about a child process on your server that pings your NodeJS app when a new item is found in SQS ? I think you can implement the child process as a watcher in BASH without using NodeJS. You can also look into npm modules if there is already one for this.
 
In short, there are many ways you can poll but polling has to be done one way or the other if you are working with Amazon SQS. 
 
I am not sure about this but if you want to be notified of items, you might want to look into Amazon SNS.