fix: mark DAGs as stale when their bundle is removed from config #67271

[bramhanandlingala]

Problem

When a DAG bundle is removed from dag_bundle_config_list, sync_bundles_to_db logs "DAG bundle X is no longer found in config and has been disabled" and correctly sets bundle.active = False, but it never updates the associated DagModel rows to is_stale = True. As a result, the removed bundle's DAGs remain visible in the UI as functional workflows.

Root cause

In DagBundlesManager.sync_bundles_to_db (airflow-core/src/airflow/dag_processing/bundles/manager.py), the loop that handles bundles absent from config only sets bundle.active = False and cleans up import errors. There is no statement to flip DagModel.is_stale.

Changes

airflow-core/src/airflow/dag_processing/bundles/manager.py

Added update to the sqlalchemy import.

Added a local import of DagModel (alongside the existing ParseImportError local import, to avoid circular imports).
After marking a bundle inactive, execute a bulk UPDATE dag SET is_stale = true WHERE bundle_name = .
airflow-core/tests/unit/dag_processing/bundles/test_dag_bundle_manager.py

Updated the clear_db fixture to also clear DagModel rows before/after tests.

Added test_sync_bundles_to_db_marks_dags_stale_on_bundle_removal, creates a bundle, adds a non-stale DAG for it, removes the bundle from config, and asserts dag.is_stale is True.

[bramhanandlingala]

@jedcunningham @ephraimbuddy
Can I request You , please review the Mergeable report , approve for the merge

thanks in advance
Bram

[potiuk]

@bramhanandlingala — I've removed the ready for maintainer review label because the next step here is yours: this branch now has merge conflicts with main. It'll go back into the maintainer queue automatically once you rebase onto the latest main and push — no need to re-add the label by hand. There's no rush.

_{Automated triage note drafted by an AI-assisted tool — may get things wrong; a real Apache Airflow maintainer takes the next look once it's green. (why automated)}

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Drafted-by: Claude Code (Opus 4.8); reviewed by @potiuk before posting

[ephraimbuddy]

This was fixed in 3.2.2. See PR: #66948

Blocking merge. Can you tell me if you reproduced this in 3.2.2 or latest main?

[shahar1]

See See #70437 (review)