CTRL_C is mostly followed by a lot of asyncio exceptions

[neilyoung]

I'm running this nice server as an asyncio task. I can't really complain about functional things, everything runs so far for me. Version is 0.14.0.

When the server is started and no interaction with some client has happened so far, I can CTRL_C w/o problem. But already with the first REST call and a following CTRL_C this appears on the prompt:

ERROR:    Traceback (most recent call last):
  File "/home/pi/.local/lib/python3.9/site-packages/starlette/routing.py", line 686, in lifespan
    await receive()
  File "/home/pi/.local/lib/python3.9/site-packages/uvicorn/lifespan/on.py", line 137, in receive
    return await self.receive_queue.get()
  File "/usr/lib/python3.9/asyncio/queues.py", line 166, in get
    await getter
asyncio.exceptions.CancelledError

If I'm doing more and more things, even Websocket service, the error list can grow rapidly:

ERROR:    Traceback (most recent call last):
  File "/home/pi/.local/lib/python3.9/site-packages/starlette/routing.py", line 686, in lifespan
    await receive()
  File "/home/pi/.local/lib/python3.9/site-packages/uvicorn/lifespan/on.py", line 137, in receive
    return await self.receive_queue.get()
  File "/usr/lib/python3.9/asyncio/queues.py", line 166, in get
    await getter
asyncio.exceptions.CancelledError

ERROR:    Exception in ASGI application
Traceback (most recent call last):
  File "/home/pi/.local/lib/python3.9/site-packages/uvicorn/protocols/websockets/websockets_impl.py", line 247, in run_asgi
    result = await self.app(self.scope, self.asgi_receive, self.asgi_send)
  File "/home/pi/.local/lib/python3.9/site-packages/uvicorn/middleware/proxy_headers.py", line 84, in __call__
    return await self.app(scope, receive, send)
  File "/home/pi/.local/lib/python3.9/site-packages/fastapi/applications.py", line 1106, in __call__
    await super().__call__(scope, receive, send)
  File "/home/pi/.local/lib/python3.9/site-packages/starlette/applications.py", line 122, in __call__
    await self.middleware_stack(scope, receive, send)
  File "/home/pi/.local/lib/python3.9/site-packages/starlette/middleware/errors.py", line 149, in __call__
    await self.app(scope, receive, send)
  File "/home/pi/.local/lib/python3.9/site-packages/starlette/middleware/exceptions.py", line 68, in __call__
    await self.app(scope, receive, sender)
  File "/home/pi/.local/lib/python3.9/site-packages/fastapi/middleware/asyncexitstack.py", line 17, in __call__
    await self.app(scope, receive, send)
  File "/home/pi/.local/lib/python3.9/site-packages/starlette/routing.py", line 718, in __call__
    await route.handle(scope, receive, send)
  File "/home/pi/.local/lib/python3.9/site-packages/starlette/routing.py", line 341, in handle
    await self.app(scope, receive, send)
  File "/home/pi/.local/lib/python3.9/site-packages/starlette/routing.py", line 82, in app
    await func(session)
  File "/home/pi/.local/lib/python3.9/site-packages/fastapi/routing.py", line 325, in app
    await dependant.call(**values)
  File "/home/pi/test/api.py", line 137, in send_data
    # Handle messages received if needed
  File "/home/pi/.local/lib/python3.9/site-packages/starlette/websockets.py", line 112, in receive_text
    message = await self.receive()
  File "/home/pi/.local/lib/python3.9/site-packages/starlette/websockets.py", line 45, in receive
    message = await self._receive()
  File "/home/pi/.local/lib/python3.9/site-packages/uvicorn/protocols/websockets/websockets_impl.py", line 360, in asgi_receive
    data = await self.recv()
  File "/home/pi/.local/lib/python3.9/site-packages/websockets/legacy/protocol.py", line 552, in recv
    await asyncio.wait(
  File "/usr/lib/python3.9/asyncio/tasks.py", line 413, in wait
    return await _wait(fs, timeout, return_when, loop)
  File "/usr/lib/python3.9/asyncio/tasks.py", line 529, in _wait
    await waiter
asyncio.exceptions.CancelledError

Somewhere on the traceback is also code of mine.

Is it generally a problem to break out from Unicorn services with CTRL_C? Should that be done by maybe intercepting SIGINT and do some more controlled stuff?