[AIRFLOW-6140] Add missing types for some core classes.

[potiuk]

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Jira

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  • https://issues.apache.org/jira/browse/AIRFLOW-6140

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[potiuk]

That's the first of the following PRs after executors unentangling - adds some missing types and cleans up some of the core classes.

[codecov-io]

Codecov Report

Merging #6702 into master will decrease coverage by 0.31%.
The diff coverage is 87.36%.

@@            Coverage Diff             @@
##           master    #6702      +/-   ##
==========================================
- Coverage    83.9%   83.59%   -0.32%     
==========================================
  Files         668      668              
  Lines       37687    37720      +33     
==========================================
- Hits        31622    31532      -90     
- Misses       6065     6188     +123

Impacted Files	Coverage Δ
airflow/configuration.py	89.13% <ø> (-3.63%)	⬇️
airflow/__init__.py	100% <100%> (ø)	⬆️
airflow/serialization/serialized_objects.py	91.22% <100%> (+0.27%)	⬆️
airflow/macros/__init__.py	82.35% <100%> (+1.1%)	⬆️
airflow/config_templates/airflow_local_settings.py	60.86% <65.51%> (-0.84%)	⬇️
airflow/models/baseoperator.py	96.05% <95.74%> (-0.25%)	⬇️
airflow/kubernetes/volume_mount.py	44.44% <0%> (-55.56%)	⬇️
airflow/kubernetes/volume.py	52.94% <0%> (-47.06%)	⬇️
airflow/kubernetes/pod_launcher.py	45.25% <0%> (-46.72%)	⬇️
airflow/kubernetes/refresh_config.py	50.98% <0%> (-23.53%)	⬇️
... and 3 more

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[kaxil]

When is this helpful?

[potiuk]

It's only when the dag has never been set. We could also throw an exception here (or assert :)), but I think returning empty set is a better choice (because no Dag has no relative ids :D).

With MyPy we now detect many places where None'able (i.e. Optional) field is used to call a method which is great because it really avoids having a mysterious errors during development.

[potiuk]

Hey @kaxil - re-reviewed and corrected. Pls take a look .

[mik-laj]

It looks like unrelated changes.

[potiuk]

True. It was for debugging of a problem. Will revert.

[feluelle]

LGTM 👍 (after you revert the AIRFLOW_CI_SILENT change)