kaxil opened a new pull request, #53838: URL: https://github.com/apache/airflow/pull/53838
Resolves `DetachedInstanceError` when scheduler processes task instances that have timed out during heartbeat detection. The error occurred when Pydantic validation of `TIRunContext` attempted to access the `consumed_asset_events` relationship on `DagRun` objects that had been detached from the `SQLAlchemy` session. It is still puzzling why this happens since the timer creates its own session in `_find_and_purge_task_instances_without_heartbeats` but seems to work (i.e. I have seen it happen). Longer term using `back_populates` (with `lazy="selectin"`) might be better so we don't need to remember this: https://docs.sqlalchemy.org/en/20/orm/queryguide/relationships.html https://docs.sqlalchemy.org/en/20/orm/relationship_api.html#sqlalchemy.orm.relationship.params.back_populates Intermittent nature makes testing non-trivial - Bug depends on some timing issue. - Tough to reliably reproduce the race condition - Mock-heavy test would not provide meaningful coverage of the actual SQLAlchemy session lifecycle <!-- Licensed to the Apache Software Foundation (ASF) under one or more contributor license agreements. See the NOTICE file distributed with this work for additional information regarding copyright ownership. The ASF licenses this file to you under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at http://www.apache.org/licenses/LICENSE-2.0 Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License. --> <!-- 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 an 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/ --> <!-- Please keep an empty line above the dashes. --> --- **^ Add meaningful description above** Read the **[Pull Request Guidelines](https://github.com/apache/airflow/blob/main/contributing-docs/05_pull_requests.rst#pull-request-guidelines)** for more information. In case of fundamental code changes, an Airflow Improvement Proposal ([AIP](https://cwiki.apache.org/confluence/display/AIRFLOW/Airflow+Improvement+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 a newsfragment file, named `{pr_number}.significant.rst` or `{issue_number}.significant.rst`, in [airflow-core/newsfragments](https://github.com/apache/airflow/tree/main/airflow-core/newsfragments). -- 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]
