Fix deprecation warning in Query.get_or_404() for SQLAlchemy 2.x

[mreid-tt]

Description

This pull request updates Query.get_or_404() to remove the use of the deprecated Query.get() method, which triggers a LegacyAPIWarning under SQLAlchemy 2.x.

The change aligns get_or_404() with the SQLAlchemy 2.x API by using the session’s get() method instead. This preserves existing behavior while ensuring forward compatibility and eliminating the deprecation warning.

fixes #1404

Additional Notes

• No behavioral changes are introduced beyond internal API alignment.
• first_or_404() and one_or_404() are unaffected, as they do not use deprecated methods.

[davidism]

We should avoid private APIs. Make a request to SQLAlchemy to make this a publicly supported API first.

[mreid-tt]

Thanks for catching that! I’ve updated the implementation to use the public API instead of the private one. It now relies on column_descriptions to resolve the mapped class.

[davidism]

Wait a second, this issue and PR make no sense. This still is a method on Query, which is the legacy API. Using the new select API from within it makes no sense, just don't use query to begin with in that case.

I'd really appreciate if you don't use AI to continue this conversation.

[mreid-tt]

Wait a second, this issue and PR make no sense. This still is a method on Query, which is the legacy API. Using the new select API from within it makes no sense, just don't use query to begin with in that case.

To be honest, I’m not a Python expert; I was mainly frustrated by the repeated deprecation warnings. Since the repository hasn’t seen much recent maintenance, I decided to try a small fix. The goal wasn’t a full refactor, just a minimal change to remove the warnings and hopefully support a minor release, given that it’s been about two years since the last one.

[davidism]

Going to close this then. I'd recommend using flask-sqlalchemy-lite and moving to use the sqlalchemy select api directly, if all you want to do is use modern sqlalchemy without warnings.

[davidism]

Also, we've already provided modern methods for quite some time: https://flask-sqlalchemy.readthedocs.io/en/stable/queries/#queries-for-views.