如何干净地异步关闭Node.js服务

Question

My NodeJS service needs to cleanly exit in the case where either a user hits ctrl-c , or, when running on Heroku, it is shutdown (say to be restarted). To cleanly shut it down I need to perform a bunch of async actions, such as emit a 'shutdown' event to RabbitMQ (so other servics know it's gone away), close database connection cleanly, and wait for any processes that are currently mid-job to be finished.

The docs say that any code I run as an exit event handler can not be async.

Listener functions must only perform synchronous operations. The Node.js process will exit immediately after calling the 'exit' event listeners causing any additional work still queued in the event loop to be abandoned.

So, given that, how do I cleanly shut down my server?

Answer 1

This will handle ctrl-c :

process.on("SIGINT", () => {
  setTimeout(() => {
    process.exit();
  }, 3000);
});

I'm not sure of the Heroku half of the question but I hope this at least helps.