Replace principle by principal in kerberos-related code

[brouberol]

Kerberos has the notion of a principal. "principle" seemed to be a typo.

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[potiuk]

Even if it's a typo fix, it crosses airflow/providers boundaries - which means that you would have to implement compatibilty layer in both airflow and providers:

1. so that new airflow supports old providers
2. so that old airflow (2.8+ currently) supports new providers

I think the hassle is not worth the typo fix

[eladkal]

I think the hassle is not worth the typo fix

We can just have a function with the correct name and deprecate the old one
given that we are going to remove all deprecations before 2.11 I think it's good chance to do it

Ah sorry this involves also Airflow core

Still I think we can do it with Airflow 3 and backport to 2.10.. this is pretty minor and easy to do.

[potiuk]

Still I think we can do it with Airflow 3 and backport to 2.10.. this is pretty minor and easy to do.

If @brouberol wishes to do the back-compatiblity code for both issues, we can do it, yes.

[eladkal]

OK lets take it by steps:

1. changes to airflow/security/kerberos.py should be in a separated PR. Add new function get_kerberos_principal with the logic and deprecate get_kerberos_principle once this PR is merged to main branch, we can start similar PR for v2.10-test branch.
2. once (1) is completed we can handle the provider changes

I can handle (1) if you prefer

[brouberol]

I can give it a go, but I'll be a bit tied up in the coming days. Feel free to proceed with 1) if you want. If not, I'll try to address your comment when I have the time. Thanks again!

[eladkal]

Cool but actually we need (2) ready before (1)

All you need to do here is to remove the changes to airflow/security/kerberos.py and tests/security/test_kerberos.py.

Keep the changes you have in providers but change the imports to:

#todo: remove try/exception when min airflow version is 3.0
try:
    from airflow.security.kerberos import get_kerberos_principal
except ModuleNotFoundError:
    from airflow.security.kerberos import get_kerberos_principle

Once you do that provider is compatible with both name and I can do the change to airflow core.

[brouberol]

I've reworked this patch to only rename the affected function, and have opened #44150 that attempts to import the fixed function and falls back to the typoed one, as suggested in #43679 (comment)

[eladkal]

Lets add 43679.misc.rst in newsfragments.
Just need to say in the file that we renamed the function due to misspelling. This will be used to generate the release notes.

Stale