How to make async callables in rust to call from Python?

[ararog]

I'm working on ASGI and RSGI protocol implementations in my project, I would like know how to declare them in rust to be called from Python?

In a sync context, we usually defined a struct with #[pyclass].

Maybe under call return a coroutine with help of future_into_py?

[davidhewitt]

At the moment I think __call__ with use of future_into_py is probably the way to go.

PyO3's experimental-async feature will probably have support for async fn __call__ "soon" - it's on my list of things to do, though I cannot guarantee exactly when I'll land that.