Fixing group streams

[nmalzieu]

Introduction 📟

Sometimes groups were not getting streamed well in the RN SDK, especially when streaming messages at the same time

Purpose ℹ️

Make group streaming still work even if streaming all messages at the same time

Scope 🔭

We were using a single StreamHolder so when cancelling a Task if something was streamed we were detecting it (with for instance Task.isCancelled and calling self.streamHolder.stream?.end() on a stream which might not be the one we thought! Using an actor inside each streaming method to save & end the stream fixes it.

Testing 🧪

I never managed to do a reproducible test directly in Swift. However I do have a failing test in the React Native repo: can stream groups and messages is failing on iOS on my side, but if I bring these Swift changes inside the XMTP Pod, it passes.

See xmtp/xmtp-react-native#503

[nplasterer]

Nice find! Probably need to bump the pod so we can get it in RN.