Nick-Nal opened a new issue, #40932: URL: https://github.com/apache/airflow/issues/40932
### Apache Airflow version 2.9.3 ### If "Other Airflow 2 version" selected, which one? _No response_ ### What happened? Greetings I've stumbled upon a problem and inconsistency with datetime-typed DAG params Let's take a DAG with datetime param that has a default value matching end of some day - 23:59:59.999999 ```python "metrics_end_time": Param( default = pendulum.now(tz = "UTC").first_of("quarter").end_of("day").subtract(days = 1).isoformat(), type = "string", format = 'date-time', title = "metrics_end_time", description = "Upper bound for general metrics calculation time period" ) ``` It works just as expected for any scheduled runs, all fractions of the second passed correctly But if I want to trigger that same DAG manually from UI there's no way to launch it with preserving fractional part ![image](https://github.com/user-attachments/assets/7aa7abbb-9eea-4ae0-994b-a9b4b8e53cbc) Firstly, this param showing up in UI without any fractional part at all Secondly, even if fractional part will be typed in this field (as '2024-07-22T23:59:59.999999+00:00', for example) - value won't be saved, DAG will start with allballs in fractional part I'm understanding all workarounds, but it looks like an incosistency that shoud be fixed ### What you think should happen instead? _No response_ ### How to reproduce Try to manually run from UI any DAG with datetime param with fractional part in seconds - the fractional part will be missed ### Operating System Ubuntu 22.04 ### Versions of Apache Airflow Providers _No response_ ### Deployment Virtualenv installation ### Deployment details _No response_ ### Anything else? _No response_ ### Are you willing to submit PR? - [ ] Yes I am willing to submit a PR! ### Code of Conduct - [X] I agree to follow this project's [Code of Conduct](https://github.com/apache/airflow/blob/main/CODE_OF_CONDUCT.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. To unsubscribe, e-mail: commits-unsubscr...@airflow.apache.org.apache.org For queries about this service, please contact Infrastructure at: us...@infra.apache.org