Compression

[davidbrochart]

I see compression uses zlib. It seems to be one potential CPU-bound operation. In an async framework, one would run that in a thread to avoid blocking the event loop, but since wsproto is a sans-IO library, I don't know what to do. Running handlers in a thread in my async web framework is not an option because I need to access an object that cannot be shared between multiple threads.

[Kriechi]

Isn't this exactly what asyncio in Python helps with? Generally speaking, for each incoming WebSocket connection, you would start processing events on its own independent thread / event loop / etc. Without some code snippets, it is difficult to discuss your exact issue in detail. I assume this issue is however not specific to wsproto as a library, but applies to all server backend architectures were one connection needs to handle events and process them one by one.

[davidbrochart]

Usually, an async web application (e.g. ASGI) uses one global event loop and handlers are async tasks scheduled on that event loop. If there are CPU-bound operations they are usually run in a thread using e.g. asyncio.to_thread. But wsproto being a sans-IO library, nothing is async so compression ends-up blocking the event loop if data is big enough.