Fix apache#47555: PostgreSQL URI driver issue

[Dong-yeong0]

This PR fixes an issue(#47555) where Airflow incorrectly generates a PostgreSQL connection URI using postgres:// instead of postgresql://, which causes SQLAlchemy to fail.

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[jason810496]

Looks good! Only the test needs to be added.

[potiuk]

I don't thnk this is needed/useful. Get_uri - returns "airflow" URI format as described in https://airflow.apache.org/docs/apache-airflow/stable/howto/connection.html#uri-format-example, the #38831 was indeed a way how to get another uri (sqlalchemy URI) - which is pretty different than AIrfow's has different potential parameters and uses postgres as prefix exclusively.

If anything - maybe it's worth (and change this PR into it) to add comment that this is NOT sqlalchemy URI and that sqlalchemy_url should be used instead.

It also makes it very fishy to add postgres-specific code in airflow models anyway.

[Dong-yeong0]

@potiuk My intention was to allow get_uri() in the Connection model to directly return a SQLAlchemy-compatible URI. However, I now see that my approach was incorrect.

If using sqlalchemy_url is the proper way, would it be better to update the get_uri() in models/connection.py docstring instead?

I can modify the PR accordingly.

[potiuk]

@potiuk My intention was to allow get_uri() in the Connection model to directly return a SQLAlchemy-compatible URI. However, I now see that my approach was incorrect.

If using sqlalchemy_url is the proper way, would it be better to update the get_uri() in models/connection.py docstring instead?

I can modify the PR accordingly.

Yep. That's better approach. It did cause confusion before so you are not the first one. It would be great to have it better decribed in docstring but also maybe even in documentation if we find a good place ?

[Dong-yeong0]

@potiuk My intention was to allow get_uri() in the Connection model to directly return a SQLAlchemy-compatible URI. However, I now see that my approach was incorrect.
If using sqlalchemy_url is the proper way, would it be better to update the get_uri() in models/connection.py docstring instead?
I can modify the PR accordingly.

Yep. That's better approach. It did cause confusion before so you are not the first one. It would be great to have it better decribed in docstring but also maybe even in documentation if we find a good place ?

I’ll update the get_uri() docstring to clearly describe that it does not return a SQLAlchemy-compatible URI, also i’ll check the documentation to find a good place to add this clarification.

[potiuk]

NICE

[jason810496]

Thanks @Dong-yeong0, but the ruff static check need fix.

[boring-cyborg]

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