pierrejeambrun opened a new issue, #53025: URL: https://github.com/apache/airflow/issues/53025
### Body I was working on https://github.com/apache/airflow/issues/53002. Starting from the DAG: ```python from datetime import datetime from airflow import Dataset from airflow.decorators import dag from airflow.providers.standard.operators.python import BranchPythonOperator from airflow.providers.standard.operators.empty import EmptyOperator # these two will have downstream dags left = Dataset("left") right = Dataset("right") @dag(start_date=datetime(1970, 1, 1), schedule=None) def branch_empty(): l = EmptyOperator(task_id="left", outlets=[left]) c = EmptyOperator(task_id="center", outlets=[]) r = EmptyOperator(task_id="right", outlets=[right]) BranchPythonOperator( task_id="decide", python_callable=lambda: ["left", "center"] ) >> [l, c, r] branch_empty() ``` Running the DAG. Then creating a new version with an additional task: ``` from datetime import datetime from airflow import Dataset from airflow.decorators import dag from airflow.providers.standard.operators.empty import EmptyOperator from airflow.providers.standard.operators.python import BranchPythonOperator, PythonOperator # these two will have downstream dags left = Dataset("left") right = Dataset("right") @dag(start_date=datetime(1970, 1, 1), schedule=None) def branch_empty(): l = EmptyOperator(task_id="left", outlets=[left]) c = EmptyOperator(task_id="center", outlets=[]) r = EmptyOperator(task_id="right", outlets=[right]) rr = PythonOperator(task_id="right_right", outlets=[], python_callable=lambda: None) BranchPythonOperator(task_id="decide", python_callable=lambda: ["left", "center"]) >> [l, c, r, rr] branch_empty() ``` Wait for the new version, refresh the UI, grid won't load anymore with error 500, and the server displaying: <img width="1889" height="933" alt="Image" src="https://github.com/user-attachments/assets/d10839ae-d8a3-4399-8e77-6161cdab6d50"; /> ### Committer - [x] I acknowledge that I am a maintainer/committer of the Apache Airflow project. -- 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]
