potiuk opened a new pull request #15182: URL: https://github.com/apache/airflow/pull/15182
This PR fixes a problem introduced by #14144 This is a very weird and unforeseen issue. The change introduced a new import from flask `before_render_template` and this caused flask to require `blinker` dependency, even if it was not specified before as 'required' by flask. We have not seen it before, because changes to this part of the code do not trigger K8S tests, however subsequent PRs started to fail because the setup.py did not have `blinker` as dependency. However in CI image `blinker` was installed because it is needed by sentry. So the problem was only detectable in the production image. This is an ultimate proof that our test harness is really good in catchig this kind of errors. The root cause for it is described in https://stackoverflow.com/questions/38491075/flask-testing-signals-not-supported-error Flask support for signals is optional and it does not blinker as dependency, but importing some parts of flask triggers the need for signals. <!-- 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/master/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/master/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. For queries about this service, please contact Infrastructure at: [email protected]
