Tornado: Can I run code after calling self.finish() in an asynchronous RequestHandler?

Question

I\'m using Tornado. I have a bunch of asynchronous request handlers. Most of them do their work asynchronously, and then report the result of that work back to the user. But

Answer 1

Yes, you can.

You have to define on_finish method of your RequestHandler. This is a function run after the request finished and has sent the response to client.

RequestHandler.on_finish()

Called after the end of a request.

Override this method to perform cleanup, logging, etc. This method is a counterpart to prepare. on_finish may not produce any output, as it is called after the response has been sent to the client.

Answer 2

Yes, your code after self.finish() will work reliably. But you can't call self.finish() twice - it will raise an exception. You can use self.finish() to close connection before all work on server is done.

But as Cole Maclean told - don't do heavy work after finish. Look for another way to do heavy tasks in background.