Static file serving: redirect / to /index.html

[shot-codes]

Pain point
I have a folder of static files that I serve:

app = socketio.ASGIApp(
    sio,
    static_files={
        "/":  "/home/.../build",
    },
)

It's frustrating that I have to access it via the URL pattern localhost:5000/index.html

Desired solution
If serving an entire folder I would like the route to automatically point to index.html, while still being able to resolve all other files in the build directory

Alternatives
The alternative is running something like Flask, FastAPI, Django etc. But using just socketio and running programatically with uvicorn suits my needs well except for this one point.

Logs
I guess this isn't so relevant as its expected but I get the following error when i try to access my static files at localhost:5000/

IsADirectoryError: [Errno 21] Is a directory: '/home/.../build'
INFO:     127.0.0.1:51540 - "GET / HTTP/1.1" 500 Internal Server Error

[miguelgrinberg]

Do you get an error stack trace? The 500 error means that something crashed. It would be useful to see this stacktrace if you have it.

[shot-codes]

yes ofc, sorry for not providing it in the original post.

ERROR:    Exception in ASGI application
Traceback (most recent call last):
  File "/home/.../.venv/lib/python3.12/site-packages/uvicorn/protocols/http/h11_impl.py", line 403, in run_asgi
    result = await app(  # type: ignore[func-returns-value]
             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/.../.venv/lib/python3.12/site-packages/uvicorn/middleware/proxy_headers.py", line 60, in __call__
    return await self.app(scope, receive, send)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/.../.venv/lib/python3.12/site-packages/engineio/async_drivers/asgi.py", line 73, in __call__
    await self.serve_static_file(static_file, receive, send)
  File "/home/.../.venv/lib/python3.12/site-packages/engineio/async_drivers/asgi.py", line 83, in serve_static_file
    with open(static_file['filename'], 'rb') as f:
         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
IsADirectoryError: [Errno 21] Is a directory: '/home/.../build'
INFO:     127.0.0.1:49882 - "GET / HTTP/1.1" 500 Internal Server Error

[miguelgrinberg]

Thanks. I believe the problem is that you are mapping / to /home/.../build, which looks like a file. To indicate that you want folder behavior (which includes the attachment of a default index.html) you have to end on a slash:

    static_files={
        "/":  "/home/.../build/",
    },

Give that a try and let me know if that solves the problem.

[shot-codes]

You are absolutely right Miguel, adding the trailing slash solves my problem. Sorry for wasting your time with such an oversight on my end. Appreciate the help :)