[New-bugs-announce] [issue44764] Handling interruption in async tasks

[Ilian Iliev]

New submission from Ilian Iliev <ilian at ilian.io>:

The idea is to provide a way for graceful shutdown so that if an interruption occurs all async tasks are given a certain time to finish before we exit the process.

Please take a look at the provided example -> https://gist.github.com/IlianIliev/9aba04a74a4faddf0749533205d3b001

If the interruption happens during an await (if we use `await asyncio.sleep(5)`), all works correctly. The exception is raised to the root level and we do the graceful shutdown on line 37.

But if the interruption happens during a normal execution (`time.sleep()`) it is raised at the currently running line and this way breaks the function without any chances or recovery. 
While `time.sleep` is not that widely used, the same problem occurs if we have any other long-running code e.g. iterating over a big list.

This was found while looking for a way to provide a graceful shutdown for the grpcio server -> https://github.com/grpc/grpc/issues/26123

Is it possible to change the behaviour so the exception is raised on a higher level when sync tasks are executed in async context?

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hgrepos: 407
messages: 398400
nosy: ilian
priority: normal
severity: normal
status: open
title: Handling interruption in async tasks
type: behavior
versions: Python 3.9

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Python tracker <report at bugs.python.org>
<https://bugs.python.org/issue44764>
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