AIP-83: Restore Uniqueness Constraint on Logical Date, Make It Nullable

[vatsrahul1001]

closes:#46187

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[vatsrahul1001]

Need to look at failures.

[uranusjr]

I added a couple of changes to fix tests in ways I think make more sense. This looks good to me except the parts involving backfill; deferring those to Daniel.

[sunank200]

Apart from the above comments I think we should add more test for logical_dates as null especially in models.

[dstandish]

Let's take the backfill part of this out; we can just do minimal changes to backfill such that tests are passing. Backfill can be broken if necessary as a result of this and fixed by sneha's PR. But we need to get the constraint change in there.

[uranusjr]

Let’s take out the changes in backfill.py from this PR so we can merge the model changes first. Everything else sort of depends on them. This means backfilling would break if you hit a duplicate logical date, but I think it’s fine as long as we fix it before the final release.

I’ll do that tomorrow if nobody beats me to it.

[vatsrahul1001]

@uranusjr @dstandish I have removed backfill related changes from this PR. We should be good to merge this after CI is green

[dstandish]

@uranusjr @dstandish I have removed backfill related changes from this PR. We should be good to merge this after CI is green

ok cool

[Lee-W]

LGTM. @uranusjr if it also looks good to me, I think we could probably just merge it?

[uranusjr]

Made a change in tests, I’ll merge this once everything is green.

[ashb]

providers/tests/amazon/aws/operators/test_dms.py:503: in test_template_fields_native
    context = ti.get_template_context(session)
airflow/models/taskinstance.py:3242: in get_template_context
    return _get_template_context(
airflow/models/taskinstance.py:960: in _get_template_context
    dag_run=DagRunSDK.model_validate(dag_run, from_attributes=True),
E   pydantic_core._pydantic_core.ValidationError: 1 validation error for DagRun
E   logical_date
E     Input should be a valid datetime [type=datetime_type, input_value=None, input_type=NoneType]
E       For further information visit https://errors.pydantic.dev/2.10/v/datetime_type

It's curious/a massive oversight in tests that this is broken but it's only a provider test that picks it up!

[potiuk]

It's curious/a massive oversight in tests that this is broken but it's only a provider test that picks it up!

Yep. I would really be curious to see what's the solution - maybe it's just a test case, maybe that's something that it's missing in the unit tests. Or maybe we should bring back all provider tests to be run on core changes - they are disabled now but seems to be breaking things more often.