ASGI 3.0.0 (2019-03-03) ¶
There has been significant work towards a 3.0 version of the ASGI specification, which uses a single-callable interface, rather than the previous double-callable structure:
async def asgi(scope, receive, send)
This will result in simpler ASGI implementations and neater tracebacks.
Servers such as Daphne, Uvicorn, and Hypercorn will remain compatible with both versions of the specification for the foreseeable future.