Define NoneType response

[nggit]

Can we define the NoneType response to just exit the app without doing anything?

from starlette.applications import Starlette
from starlette.routing import Route


async def homepage(request):
    return  # exit app


routes = [
    Route('/', homepage, methods=['GET', 'POST']),
]

app = Starlette(routes=routes)

This allows use cases like this "Experimental Features" without hassle.

Changing this is unlikely to have any impact as servers generally already handle this:

ERROR:    ASGI callable returned without starting response.

And is even a bit cleaner than the current behavior:

File "/home/tux/.local/lib/python3.12/site-packages/starlette/routing.py", line 74, in app
               await response(scope, receive, send)
                     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
           TypeError: 'NoneType' object is not callable

[Kludex]

You need to use Response.

The idea is that the endpoint returns an ASGI app.

[nggit]

Thanks for the answer.

In the general case of course we use Response .

By defining NoneType behavior instead of undefined behavior just adds another use cases benefit.

        async def app(scope: Scope, receive: Receive, send: Send) -> None:
            response = await f(request)
       +    if response is None:
       +        return
            await response(scope, receive, send)