Updating Uvicorn to 0.14.0 to increase ws max_size to > 1mb causes a cascade of errors

[turukawa]

Updated and cross-referenced from https://github.com/tiangolo/uvicorn-gunicorn-docker/issues/74

I needed to update Uvicorn to 0.14.0 since this version permits websockets to send > 1mb of data in a message. I update in Poetry. When I restart the Docker image, I get the following error scrolling off indefinitely:

backend_1 | error walking file system: FileNotFoundError [Errno 2] No such file or directory: '/app/.venv/bin/python'

These articles give me some indication it has something to do with Uvicorn and reload:

• FastAPI/Starlette debug vs prod
• FastAPI How to fix error walking file system

I created a custom version of /start-reload.sh with the following to reload the app directory only:

LOG_LEVEL=${LOG_LEVEL:-critical}
APP_DIRECTORY=${APP_DIRECTORY:-./app/app}
WS=${WS:-auto}
WS_MAX=${WS_MAX:-15728640}
exec uvicorn --reload --reload-dir $APP_DIRECTORY --host $HOST --port $PORT --ws $WS --ws-max-size $WS_MAX "$APP_MODULE"

This makes no difference at all, and I'd appreciate any help, both with the data send limit, and this never-ending .venv not found error.

Thanks.

Here's the stack trace, bracketed by never-ending FileNotFoundErrors:

backend_1 | error walking file system: FileNotFoundError [Errno 2] No such file or directory: '/app/.venv/bin/python'
backend_1 | ERROR: Exception in ASGI application
backend_1 | Traceback (most recent call last):
backend_1 | File "/opt/pyenv/versions/3.9.5/lib/python3.9/site-packages/websockets/legacy/protocol.py", line 750, in transfer_data
backend_1 | message = await self.read_message()
backend_1 | File "/opt/pyenv/versions/3.9.5/lib/python3.9/site-packages/websockets/legacy/protocol.py", line 874, in read_message
backend_1 | frame = await self.read_data_frame(max_size=max_size)
backend_1 | File "/opt/pyenv/versions/3.9.5/lib/python3.9/site-packages/websockets/legacy/protocol.py", line 895, in read_data_frame
backend_1 | frame = await self.read_frame(max_size)
backend_1 | File "/opt/pyenv/versions/3.9.5/lib/python3.9/site-packages/websockets/legacy/protocol.py", line 971, in read_frame
backend_1 | frame = await Frame.read(
backend_1 | File "/opt/pyenv/versions/3.9.5/lib/python3.9/site-packages/websockets/legacy/framing.py", line 80, in read
backend_1 | raise PayloadTooBig(f"over size limit ({length} > {max_size} bytes)")
backend_1 | websockets.exceptions.PayloadTooBig: over size limit (106508 > 24869 bytes)
backend_1 |
backend_1 | The above exception was the direct cause of the following exception:
backend_1 |
backend_1 | Traceback (most recent call last):
backend_1 | File "/opt/pyenv/versions/3.9.5/lib/python3.9/site-packages/uvicorn/protocols/websockets/websockets_impl.py", line 171, in run_asgi
backend_1 | result = await self.app(self.scope, self.asgi_receive, self.asgi_send)
backend_1 | File "/opt/pyenv/versions/3.9.5/lib/python3.9/site-packages/uvicorn/middleware/proxy_headers.py", line 59, in __call__
backend_1 | return await self.app(scope, receive, send)
backend_1 | File "/opt/pyenv/versions/3.9.5/lib/python3.9/site-packages/fastapi/applications.py", line 199, in __call__
backend_1 | await super().__call__(scope, receive, send)
backend_1 | File "/opt/pyenv/versions/3.9.5/lib/python3.9/site-packages/starlette/applications.py", line 111, in __call__
backend_1 | await self.middleware_stack(scope, receive, send)
backend_1 | File "/opt/pyenv/versions/3.9.5/lib/python3.9/site-packages/starlette/middleware/errors.py", line 146, in __call__
backend_1 | await self.app(scope, receive, send)
backend_1 | File "/opt/pyenv/versions/3.9.5/lib/python3.9/site-packages/starlette/middleware/cors.py", line 70, in __call__
backend_1 | await self.app(scope, receive, send)
backend_1 | File "/opt/pyenv/versions/3.9.5/lib/python3.9/site-packages/starlette/exceptions.py", line 58, in __call__
backend_1 | await self.app(scope, receive, send)
backend_1 | File "/opt/pyenv/versions/3.9.5/lib/python3.9/site-packages/starlette/routing.py", line 566, in __call__
backend_1 | await route.handle(scope, receive, send)
backend_1 | File "/opt/pyenv/versions/3.9.5/lib/python3.9/site-packages/starlette/routing.py", line 283, in handle
backend_1 | await self.app(scope, receive, send)
backend_1 | File "/opt/pyenv/versions/3.9.5/lib/python3.9/site-packages/starlette/routing.py", line 57, in app
backend_1 | await func(session)
backend_1 | File "/opt/pyenv/versions/3.9.5/lib/python3.9/site-packages/fastapi/routing.py", line 247, in app
backend_1 | await dependant.call(**values)
backend_1 | File "/app/./app/api/api_v1/endpoints/epub.py", line 52, in websocket_endpoint2
backend_1 | await websocket.send_json(response)
backend_1 | File "/opt/pyenv/versions/3.9.5/lib/python3.9/site-packages/starlette/websockets.py", line 137, in send_json
backend_1 | await self.send({"type": "websocket.send", "text": text})
backend_1 | File "/opt/pyenv/versions/3.9.5/lib/python3.9/site-packages/starlette/websockets.py", line 68, in send
backend_1 | await self._send(message)
backend_1 | File "/opt/pyenv/versions/3.9.5/lib/python3.9/site-packages/uvicorn/protocols/websockets/websockets_impl.py", line 232, in asgi_send
backend_1 | await self.send(data)
backend_1 | File "/opt/pyenv/versions/3.9.5/lib/python3.9/site-packages/websockets/legacy/protocol.py", line 471, in send
backend_1 | await self.ensure_open()
backend_1 | File "/opt/pyenv/versions/3.9.5/lib/python3.9/site-packages/websockets/legacy/protocol.py", line 735, in ensure_open
backend_1 | raise self.connection_closed_exc()
backend_1 | websockets.exceptions.ConnectionClosedError: code = 1006 (connection closed abnormally [internal]), no reason
backend_1 | /opt/pyenv/versions/3.9.5/lib/python3.9/site-packages/uvicorn/protocols/websockets/websockets_impl.py:180: RuntimeWarning: coroutine 'WebSocket.receive_json' was never awaited
backend_1 | self.transport.close()
backend_1 | RuntimeWarning: Enable tracemalloc to get the object allocation traceback
backend_1 | error walking file system: FileNotFoundError [Errno 2] No such file or directory: '/app/.venv/bin/python'