[AIRFLOW-6185] SQLAlchemy Connection model schema not aligned with Alembic schema

[xinbinhuang]

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Jira

• My PR addresses the following Airflow Jira issues and references them in the PR title. For example, "[AIRFLOW-XXX] My Airflow PR"
  • https://issues.apache.org/jira/projects/AIRFLOW/issues/AIRFLOW-6185

Description

• Here are some details about my PR, including screenshots of any UI changes:
  • Create a new alembic revision to increase Connection.password to 5000, syncing with the SQLAlchemy model, and set render_as_batch=True for both online & offline migrations to work with SQLite backend.
  • Import SerializedDagModel to migrations/env.py. As SerializedDagModel was removed from models ([AIRFLOW-6010] Remove cyclic imports and pylint disables #6601 ), alembic thinks that the object was removed, and will try to remove the table in autogenerated schema migration. This can avoid the behavior

Tests

• My PR adds the following unit tests OR does not need testing for this extremely good reason:

Commits

• My commits all reference Jira issues in their subject lines, and I have squashed multiple commits if they address the same issue. In addition, my commits follow the guidelines from "How to write a good git commit message":
  1. Subject is separated from body by a blank line
  2. Subject is limited to 50 characters (not including Jira issue reference)
  3. Subject does not end with a period
  4. Subject uses the imperative mood ("add", not "adding")
  5. Body wraps at 72 characters
  6. Body explains "what" and "why", not "how"

Documentation

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  • All the public functions and the classes in the PR contain docstrings that explain what it does
  • If you implement backwards incompatible changes, please leave a note in the Updating.md so we can assign it to a appropriate release

[codecov-io]

Codecov Report

Merging #6754 into master will decrease coverage by 0.29%.
The diff coverage is n/a.

@@            Coverage Diff            @@
##           master    #6754     +/-   ##
=========================================
- Coverage   84.84%   84.55%   -0.3%     
=========================================
  Files         669      669             
  Lines       37851    37851             
=========================================
- Hits        32114    32004    -110     
- Misses       5737     5847    +110

Impacted Files	Coverage Δ
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%)	⬇️
...rflow/contrib/operators/kubernetes_pod_operator.py	78.2% <0%> (-20.52%)	⬇️

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[potiuk]

Nice!

[potiuk]

Thanks! Did not realise that was the side effect. Will remember about that!