Pyo3 update

[awestlake87]

Hey, the fix was a bit more complicated than I anticipated. Essentially, since you're using run_forever, there was no way of getting the event loop reference via get_running_loop as opposed to get_event_loop (which will fetch the global event loop). I went ahead and scoped the event loop for your index handler so that it has access to the event loop via task-local data.

I've been improving the docs on 0.14, but this problem probably isn't explicitly addressed. The "Event Loop References and Thread-Awareness" section in the docs may provide some intuition for why 0.14 acts this way.

[sansyrox]

Thank you @awestlake87 for this! ✨

Do the changes even work with v0.13.* ?

[awestlake87]

The 0.14 API is pretty different from 0.13, so it won't work with both. If you need it to work with both 0.13 and 0.14, you can delay this PR and continue using the 0.13 API with #[allow(deprecated)] since the 0.13 conversions work the same in 0.13 and 0.14.

[sansyrox]

@awestlake87 , no no. I was asking as the Cargo.toml was not updated. I will update it and check if the tests pass.

[sansyrox]

@awestlake87 , what does pyo3-asyncio::tokio::scope do?

[awestlake87]

It allows the conversions to get a reference to the current event loop via task-local data. I've got a breakdown of its motivation and usage here

[ShadowJonathan]

More specifically;

pyo3_asyncio::<runtime>::scope - Store the event loop in task-local data when executing the given Future.

pyo3_asyncio::<runtime>::scope_local - Store the event loop in task-local data when executing the given !Send Future.

This helps with subsequent calls to work with the event loop (such as acquiring python, or spawning other tasks)