nit: I don't think we need to overwrite __setitem__ and __setattr__ since it's not required by mapping and it will return the same error anyways. Or did you do it here to adapt the error message?

Correct, I did that to keep exceptions similar to high-level Secrets object, to not show internal machinery (expose AttrDict) to the final user.

ahh, ok that makes sense. But maybe one aspect to think about: if we add those methods, typing checks will think that they actually exist. So there might be a slight benefit of not adding those, to allow type/linters to directly show it as an error.

hm, my checks show that with or without __setattr__ or __setitem__ neither PyCharm nor mypy does complain about an attempt to assign to attribute or item. Only pyright complains about __setitem__ missing during item assignment.

But without having methods above, user could write something like this

x = st.secrets.servers.alpha
x.some_ip = "7.7.7.7"

st.write(x.some_ip)

Which will not work in case __setattrs__ explicitly raise an exception.

Anyway, I explicitly added NoReturn return type to the methods https://peps.python.org/pep-0484/#the-noreturn-type to explicitly indicate that they should never return successfully. Let's hope some linters in the future will highlight warnings for this.

Alright, sounds good :)