fix(scheduler): skip asset-triggered dags without SerializedDagModel by leossantos · Pull Request #64322 · apache/airflow

leossantos · 2026-03-27T18:18:20Z

Port to main (Airflow 3) of the scheduler guard from #63546: DagModel.dags_needing_dagruns could treat asset-triggered DAGs as ready for a new run when they had AssetDagRunQueue rows but no SerializedDagModel in the same evaluation window. The asset timetable / condition path was not applied consistently for those DAGs, which could allow premature asset-triggered DagRuns while the DAG processor was mid–parse cycle.

This change removes such dag_ids from the in-memory adrq_by_dag / dag_statuses maps until serialization exists. AssetDagRunQueue rows are not deleted; the scheduler can re-evaluate on a later run. A DEBUG log records skipped DAGs (missing serialization). The dags_needing_dagruns docstring documents this behavior.

Tests: two TestDagModel cases cover missing SerializedDagModel (single and multiple DAGs), DEBUG log expectations, sorted dag_id list in the message, and assert asset_dag_run_queue row counts unchanged after dags_needing_dagruns.

related: #63546

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…in dags_needing_dagruns Remove those dag_ids from the in-memory candidate set until serialization exists; retain AssetDagRunQueue rows and emit DEBUG logs. Add unit tests and a bugfix newsfragment.

…izedDagModel is unavailable

Split DagModel and AssetDagRunQueue inserts and flush after DagModel so foreign-key order matches production DB constraints in TestDagModel.

leossantos · 2026-03-30T17:51:30Z

Hi! I've fixed the failing tests and made the necessary adjustments. Could someone please approve the workflow run to verify the fixes? Thanks for the help!

airflow-core/newsfragments/64322.bugfix.rst

airflow-core/src/airflow/models/dag.py

airflow-core/tests/unit/models/test_dag.py

Co-authored-by: Wei Lee <weilee.rx@gmail.com>

Combine the missing-from-serialized set check with a walrus assignment and improve the debug message when DagRun creation is skipped for DAGs with queued asset events but no SerializedDagModel row.

leossantos · 2026-03-31T13:32:07Z

I've made adjustments to ensure the pre-commit checks pass.

Lee-W

mostly good, but needs to fix the CI

airflow-core/tests/unit/models/test_dag.py

potiuk · 2026-04-01T13:02:24Z

@leossantos This PR has been converted to draft because it does not yet meet our Pull Request quality criteria.

Issues found:

❌ Other failing CI checks: Failing: Postgres tests: core / DB-core:Postgres:14:3.10:Core...Serialization, MySQL tests: core / DB-core:MySQL:8.0:3.10:Core...Serialization, Sqlite tests: core / DB-core:Sqlite:3.10:Core...Serialization, Low dep tests:core / All-core:LowestDeps:14:3.10:Core...Serialization. Run prek run --from-ref main locally to reproduce. See static checks docs.
⚠️ Unresolved review comments: This PR has 1 unresolved review thread from maintainers: @Lee-W (MEMBER): 1 unresolved thread. Please review and resolve all inline review comments before requesting another review. You can resolve a conversation by clicking 'Resolve conversation' on each thread after addressing the feedback. See pull request guidelines.

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…nings

leossantos · 2026-04-01T19:15:37Z

I solved the issue and tested locally

Copilot

Pull request overview

Ports an Airflow scheduler guard to prevent premature asset-triggered DagRun creation when AssetDagRunQueue has queued events but the DAG is not yet available in SerializedDagModel (e.g., during a DAG processor parse/serialize window).

Changes:

Skip asset-triggered DAGs that have ADRQ rows but no corresponding SerializedDagModel row, leaving ADRQ rows intact for later re-evaluation.
Add a DEBUG log listing skipped DAG IDs (sorted) when serialization is missing.
Add unit tests covering missing-serialization scenarios (single/multiple DAGs), expected debug logging, and ensuring ADRQ row counts are unchanged; add a bugfix newsfragment.

Reviewed changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated no comments.

File	Description
airflow-core/src/airflow/models/dag.py	Adds the guard to omit ADRQ-backed DAGs missing serialization and logs skipped DAG IDs.
airflow-core/tests/unit/models/test_dag.py	Adds regression tests validating skip behavior, debug logging, and no ADRQ deletions.
airflow-core/newsfragments/64322.bugfix.rst	Documents the scheduler bugfix in release notes.

airflow-core/newsfragments/64322.bugfix.rst

airflow-core/src/airflow/models/dag.py

Co-authored-by: Jens Scheffler <95105677+jscheffl@users.noreply.github.com>

boring-cyborg · 2026-04-05T10:57:19Z

Awesome work, congrats on your first merged pull request! You are invited to check our Issue Tracker for additional contributions.

github-actions · 2026-04-05T10:58:27Z

Backport successfully created: v3-2-test

Note: As of Merging PRs targeted for Airflow 3.X
the committer who merges the PR is responsible for backporting the PRs that are bug fixes (generally speaking) to the maintenance branches.

In matter of doubt please ask in #release-management Slack channel.

Status	Branch	Result
✅	v3-2-test

@jscheffl

…zedDagModel (#64322) * fix(scheduler): skip asset-triggered dags without SerializedDagModel in dags_needing_dagruns Remove those dag_ids from the in-memory candidate set until serialization exists; retain AssetDagRunQueue rows and emit DEBUG logs. Add unit tests and a bugfix newsfragment. * fix(scheduler): prevent premature asset-triggered DagRuns when SerializedDagModel is unavailable * test(dag): persist DagModel before AssetDagRunQueue in unit tests Split DagModel and AssetDagRunQueue inserts and flush after DagModel so foreign-key order matches production DB constraints in TestDagModel. * Apply suggestions from code review Co-authored-by: Wei Lee <weilee.rx@gmail.com> * refactor(dag): clarify ADRQ skip log and condense serialized-DAG guard Combine the missing-from-serialized set check with a walrus assignment and improve the debug message when DagRun creation is skipped for DAGs with queued asset events but no SerializedDagModel row. * test(models): align caplog assertions with updated serialized dag warnings * test(dag): align ADRQ missing-serialized log assertion with message text * Apply suggestion from @jscheffl Co-authored-by: Jens Scheffler <95105677+jscheffl@users.noreply.github.com> * chore(newsfragments): remove 64322.bugfix.rst --------- (cherry picked from commit b91394a) Co-authored-by: Leonardo Soares <leoss33@outlook.com.br> Co-authored-by: Wei Lee <weilee.rx@gmail.com> Co-authored-by: Jens Scheffler <95105677+jscheffl@users.noreply.github.com>

@jscheffl

…zedDagModel (apache#64322) * fix(scheduler): skip asset-triggered dags without SerializedDagModel in dags_needing_dagruns Remove those dag_ids from the in-memory candidate set until serialization exists; retain AssetDagRunQueue rows and emit DEBUG logs. Add unit tests and a bugfix newsfragment. * fix(scheduler): prevent premature asset-triggered DagRuns when SerializedDagModel is unavailable * test(dag): persist DagModel before AssetDagRunQueue in unit tests Split DagModel and AssetDagRunQueue inserts and flush after DagModel so foreign-key order matches production DB constraints in TestDagModel. * Apply suggestions from code review Co-authored-by: Wei Lee <weilee.rx@gmail.com> * refactor(dag): clarify ADRQ skip log and condense serialized-DAG guard Combine the missing-from-serialized set check with a walrus assignment and improve the debug message when DagRun creation is skipped for DAGs with queued asset events but no SerializedDagModel row. * test(models): align caplog assertions with updated serialized dag warnings * test(dag): align ADRQ missing-serialized log assertion with message text * Apply suggestion from @jscheffl Co-authored-by: Jens Scheffler <95105677+jscheffl@users.noreply.github.com> * chore(newsfragments): remove 64322.bugfix.rst --------- (cherry picked from commit b91394a) Co-authored-by: Leonardo Soares <leoss33@outlook.com.br> Co-authored-by: Wei Lee <weilee.rx@gmail.com> Co-authored-by: Jens Scheffler <95105677+jscheffl@users.noreply.github.com>

@jscheffl

…zedDagModel (#64322) (#64738) * fix(scheduler): skip asset-triggered dags without SerializedDagModel in dags_needing_dagruns Remove those dag_ids from the in-memory candidate set until serialization exists; retain AssetDagRunQueue rows and emit DEBUG logs. Add unit tests and a bugfix newsfragment. * fix(scheduler): prevent premature asset-triggered DagRuns when SerializedDagModel is unavailable * test(dag): persist DagModel before AssetDagRunQueue in unit tests Split DagModel and AssetDagRunQueue inserts and flush after DagModel so foreign-key order matches production DB constraints in TestDagModel. * Apply suggestions from code review * refactor(dag): clarify ADRQ skip log and condense serialized-DAG guard Combine the missing-from-serialized set check with a walrus assignment and improve the debug message when DagRun creation is skipped for DAGs with queued asset events but no SerializedDagModel row. * test(models): align caplog assertions with updated serialized dag warnings * test(dag): align ADRQ missing-serialized log assertion with message text * Apply suggestion from @jscheffl * chore(newsfragments): remove 64322.bugfix.rst --------- (cherry picked from commit b91394a) Co-authored-by: Leonardo Soares <leoss33@outlook.com.br> Co-authored-by: Wei Lee <weilee.rx@gmail.com> Co-authored-by: Jens Scheffler <95105677+jscheffl@users.noreply.github.com>

@jscheffl

…zedDagModel (#64322) (#64738) * fix(scheduler): skip asset-triggered dags without SerializedDagModel in dags_needing_dagruns Remove those dag_ids from the in-memory candidate set until serialization exists; retain AssetDagRunQueue rows and emit DEBUG logs. Add unit tests and a bugfix newsfragment. * fix(scheduler): prevent premature asset-triggered DagRuns when SerializedDagModel is unavailable * test(dag): persist DagModel before AssetDagRunQueue in unit tests Split DagModel and AssetDagRunQueue inserts and flush after DagModel so foreign-key order matches production DB constraints in TestDagModel. * Apply suggestions from code review * refactor(dag): clarify ADRQ skip log and condense serialized-DAG guard Combine the missing-from-serialized set check with a walrus assignment and improve the debug message when DagRun creation is skipped for DAGs with queued asset events but no SerializedDagModel row. * test(models): align caplog assertions with updated serialized dag warnings * test(dag): align ADRQ missing-serialized log assertion with message text * Apply suggestion from @jscheffl * chore(newsfragments): remove 64322.bugfix.rst --------- (cherry picked from commit b91394a) Co-authored-by: Leonardo Soares <leoss33@outlook.com.br> Co-authored-by: Wei Lee <weilee.rx@gmail.com> Co-authored-by: Jens Scheffler <95105677+jscheffl@users.noreply.github.com>

leossantos requested review from XD-DENG and ashb as code owners March 27, 2026 18:18

leossantos mentioned this pull request Mar 27, 2026

fix: Skip dataset-triggered dags without SerializedDagModel #63546

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eladkal added this to the Airflow 3.2.0 milestone Mar 27, 2026

eladkal added the type:bug-fix Changelog: Bug Fixes label Mar 27, 2026

leossantos force-pushed the fix/asset-queue-missing-serialized-dag-guard branch from 0b227b5 to 38a59e0 Compare March 27, 2026 22:38

vatsrahul1001 modified the milestones: Airflow 3.2.0, Airflow 3.2.1 Mar 29, 2026

leossantos added 3 commits March 30, 2026 10:02

fix(scheduler): skip asset-triggered dags without SerializedDagModel …

6dc5258

…in dags_needing_dagruns Remove those dag_ids from the in-memory candidate set until serialization exists; retain AssetDagRunQueue rows and emit DEBUG logs. Add unit tests and a bugfix newsfragment.

fix(scheduler): prevent premature asset-triggered DagRuns when Serial…

a4fe148

…izedDagModel is unavailable

test(dag): persist DagModel before AssetDagRunQueue in unit tests

5f4bd8a

Split DagModel and AssetDagRunQueue inserts and flush after DagModel so foreign-key order matches production DB constraints in TestDagModel.

leossantos force-pushed the fix/asset-queue-missing-serialized-dag-guard branch from 38a59e0 to 5f4bd8a Compare March 30, 2026 13:02

Lee-W reviewed Mar 31, 2026

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leossantos and others added 2 commits March 31, 2026 09:38

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2ee9768

Co-authored-by: Wei Lee <weilee.rx@gmail.com>

refactor(dag): clarify ADRQ skip log and condense serialized-DAG guard

325174c

Combine the missing-from-serialized set check with a walrus assignment and improve the debug message when DagRun creation is skipped for DAGs with queued asset events but no SerializedDagModel row.

leossantos requested a review from Lee-W March 31, 2026 18:03

Lee-W reviewed Apr 1, 2026

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potiuk marked this pull request as draft April 1, 2026 13:02

leossantos marked this pull request as ready for review April 1, 2026 19:07

test(models): align caplog assertions with updated serialized dag war…

238af81

…nings

leossantos requested a review from Lee-W April 1, 2026 19:15

test(dag): align ADRQ missing-serialized log assertion with message text

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leossantos and others added 2 commits April 4, 2026 14:14

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Co-authored-by: Jens Scheffler <95105677+jscheffl@users.noreply.github.com>

chore(newsfragments): remove 64322.bugfix.rst

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jscheffl approved these changes Apr 4, 2026

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jscheffl added the backport-to-v3-2-test Mark PR with this label to backport to v3-2-test branch label Apr 4, 2026

Lee-W merged commit b91394a into apache:main Apr 5, 2026
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fix(scheduler): skip asset-triggered dags without SerializedDagModel#64322

fix(scheduler): skip asset-triggered dags without SerializedDagModel#64322
Lee-W merged 9 commits intoapache:mainfrom
leossantos:fix/asset-queue-missing-serialized-dag-guard

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