Fastapi: Can't assign http response status code integer bigger than 600

[brailovskiy]

Describe the bug

When i use Response class with param status_code 666 or 894, which is necessary to my project, i got a KeyError exception that crashes application.

To Reproduce

Steps to reproduce the behavior with a minimum self-contained file.

Replace each part with your own scenario:

1. Create a file with:

from fastapi import FastAPI, Response

app = FastAPI()


@app.get("/")
def read_root():
    return Response(status_code=894)

Expected behavior

Can assign any integer of three characters

Environment

• OS: [e.g. Linux /macOS]
• FastAPI Version [e.g. 0.54.1], get it with:

python -c "import fastapi; print(fastapi.__version__)"

• Python version, get it with:

python --version

3.8.2

Additional context

Traceback (most recent call last): File "/Users/ab/.virtualenvs/flask_mock/lib/python3.7/site-packages/uvicorn/protocols/http/httptools_impl.py", line 385, in run_asgi result = await app(self.scope, self.receive, self.send) File "/Users/ab/.virtualenvs/flask_mock/lib/python3.7/site-packages/uvicorn/middleware/proxy_headers.py", line 45, in __call__ return await self.app(scope, receive, send) File "/Users/ab/.virtualenvs/flask_mock/lib/python3.7/site-packages/fastapi/applications.py", line 149, in __call__ await super().__call__(scope, receive, send) File "/Users/ab/.virtualenvs/flask_mock/lib/python3.7/site-packages/starlette/applications.py", line 102, in __call__ await self.middleware_stack(scope, receive, send) File "/Users/ab/.virtualenvs/flask_mock/lib/python3.7/site-packages/starlette/middleware/errors.py", line 181, in __call__ raise exc from None File "/Users/ab/.virtualenvs/flask_mock/lib/python3.7/site-packages/starlette/middleware/errors.py", line 159, in __call__ await self.app(scope, receive, _send) File "/Users/ab/.virtualenvs/flask_mock/lib/python3.7/site-packages/starlette/exceptions.py", line 82, in __call__ raise exc from None File "/Users/ab/.virtualenvs/flask_mock/lib/python3.7/site-packages/starlette/exceptions.py", line 71, in __call__ await self.app(scope, receive, sender) File "/Users/ab/.virtualenvs/flask_mock/lib/python3.7/site-packages/starlette/routing.py", line 550, in __call__ await route.handle(scope, receive, send) File "/Users/ab/.virtualenvs/flask_mock/lib/python3.7/site-packages/starlette/routing.py", line 227, in handle await self.app(scope, receive, send) File "/Users/ab/.virtualenvs/flask_mock/lib/python3.7/site-packages/starlette/routing.py", line 44, in app await response(scope, receive, send) File "/Users/ab/.virtualenvs/flask_mock/lib/python3.7/site-packages/starlette/responses.py", line 125, in __call__ "headers": self.raw_headers, File "/Users/ab/.virtualenvs/flask_mock/lib/python3.7/site-packages/starlette/exceptions.py", line 68, in sender await send(message) File "/Users/ab/.virtualenvs/flask_mock/lib/python3.7/site-packages/starlette/middleware/errors.py", line 156, in _send await send(message) File "/Users/ab/.virtualenvs/flask_mock/lib/python3.7/site-packages/uvicorn/protocols/http/httptools_impl.py", line 458, in send content = [STATUS_LINE[status_code]] KeyError: 666

[retnikt]

This is intended behaviour; other status codes are in violation of the HTTP spec. And anyway, this is an issue with uvicorn, not FastAPI.

[phy25]

Again if you insist, either ask for help from uvicorn, or probably use another ASGI server:

https://github.com/encode/uvicorn/blob/70f023e78415b45214f8cfe4de8a11acb710e51f/uvicorn/protocols/http/httptools_impl.py#L25-L27

[brailovskiy]

Thank you, it works!

[tiangolo]

Thanks for the help here everyone! :clap: :bow:

Thanks for reporting back and closing the issue :+1: