Regular gRPC support

[public]

trafficstars

Currently everything is built assuming gRPC-Web but it doesn't seem like it would be much work to also support normal gRPC with H2 only connections although it would depend on there being a WSGI or ASGI server that could actually speak that.

• [ ] Is it feasible that any existing ASGI or WSGI servers could speak gRPC? This mostly means supporting bare H2 connections.
• [ ] What does sonora need to do to support regular gRPC?

[akshayjshah]

As I understand it, the main problem is that the HTTP/2 gRPC protocol requires sending errors as HTTP trailers. Trailers aren't specific to HTTP/2, but as far as I know they're not exposed by the WSGI standard. (I don't know about ASGI.)

Is there typically an implementation-specific way to access HTTP features that aren't part of the standard?

[public]

Re WSGI https://github.com/python-web-sig/wsgi-ng/issues/9 it's not clear if any implementations support it even via an environ extension.

Re ASGI https://github.com/django/asgiref/issues/141 I think there is some interest in providing this capability but seems like no implementations support it yet either.

[jluebbe]

Re ASGI django/asgiref#141 I think there is some interest in providing this capability but seems like no implementations support it yet either.

HTTP Trailers was added to the ASGI spec: https://github.com/django/asgiref/pull/339