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[Bug] Python FastAPI plugin does not support websocket connections
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- [X] I had searched in the issues and found no similar issues.
Apache SkyWalking Component
Python Agent (apache/skywalking-python)
What happened
There is an assertion error whenever a websocket connection gets made
What you expected to happen
Either ignore websocket connections, or support tracing them
How to reproduce
Save the following as ws_example.py
:
> cat ws_example.py
from fastapi import FastAPI, WebSocket
app = FastAPI()
@app.websocket("/ws")
async def websocket_endpoint(websocket: WebSocket):
await websocket.accept()
while True:
data = await websocket.receive_text()
await websocket.send_text(f"Message text was: {data}")
And run with sw-python run uvicorn --port 8080 ws_example:app
Make a request with
> wscat -c ws://127.0.0.1:8080/ws
error: Unexpected server response: 500
And the logs in the python service will show you
ERROR: Exception in ASGI application
Traceback (most recent call last):
File "/home/ubuntu/venv/deepalert/lib/python3.10/site-packages/uvicorn/protocols/websockets/websockets_impl.py", line 225, in run_asgi
result = await self.app(self.scope, self.asgi_receive, self.asgi_send)
File "/home/ubuntu/venv/deepalert/lib/python3.10/site-packages/uvicorn/middleware/proxy_headers.py", line 78, in __call__
return await self.app(scope, receive, send)
File "/home/ubuntu/venv/deepalert/lib/python3.10/site-packages/fastapi/applications.py", line 270, in __call__
await super().__call__(scope, receive, send)
File "/home/ubuntu/venv/deepalert/lib/python3.10/site-packages/starlette/applications.py", line 124, in __call__
await self.middleware_stack(scope, receive, send)
File "/home/ubuntu/venv/deepalert/lib/python3.10/site-packages/starlette/middleware/errors.py", line 149, in __call__
await self.app(scope, receive, send)
File "/home/ubuntu/venv/deepalert/lib/python3.10/site-packages/skywalking/plugins/sw_fastapi.py", line 45, in _sw_fast_api
req = Request(scope, receive=receive, send=send)
File "/home/ubuntu/venv/deepalert/lib/python3.10/site-packages/starlette/requests.py", line 195, in __init__
assert scope["type"] == "http"
AssertionError
Anything else
No response
Are you willing to submit PR?
- [ ] Yes I am willing to submit a PR!
Code of Conduct
- [X] I agree to follow this project's Code of Conduct
Thanks for reporting. I see the problem.