potiuk opened a new pull request #18450: URL: https://github.com/apache/airflow/pull/18450
One of our migration (adding max_tries) creates the DagBag and effectively parses all the DAGS while performing the migraiions. While this is needed in case you migrate from an older version of the DB where you have some TaskInstances requiring migration, for an empty database, there are no TaskInstance entities in the DB and parsing of all the DAGs is not needed. Actually it can even be harmful. If you attempt to run Airflow Migration on an empty dataase and your DAGs will be erroneous, your migration will break in the middle and you have no clue what caused it = see #18408 for an example of such failure. This PR skips DagBag import when there are no TaskInstance in the database to migrate. Fixes: #18449 <!-- Thank you for contributing! Please make sure that your code changes are covered with tests. And in case of new features or big changes remember to adjust the documentation. Feel free to ping committers for the review! In case of existing issue, reference it using one of the following: closes: #ISSUE related: #ISSUE How to write a good git commit message: http://chris.beams.io/posts/git-commit/ --> --- **^ Add meaningful description above** Read the **[Pull Request Guidelines](https://github.com/apache/airflow/blob/main/CONTRIBUTING.rst#pull-request-guidelines)** for more information. In case of fundamental code change, Airflow Improvement Proposal ([AIP](https://cwiki.apache.org/confluence/display/AIRFLOW/Airflow+Improvements+Proposals)) is needed. In case of a new dependency, check compliance with the [ASF 3rd Party License Policy](https://www.apache.org/legal/resolved.html#category-x). In case of backwards incompatible changes please leave a note in [UPDATING.md](https://github.com/apache/airflow/blob/main/UPDATING.md). -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: [email protected] For queries about this service, please contact Infrastructure at: [email protected]
