"user-defined function raised exception" error when accessing PeriodicTask in the admin panel

[angelojbgama]

Description:

I am encountering an error when trying to access the PeriodicTask page in the Django Celery Beat admin panel.

Error Details:

The error occurs in the following template line:

{% block date_hierarchy %}{% if cl.date_hierarchy %}{% date_hierarchy cl %}{% endif %}{% endblock %}

The issue is resolved when I comment out the following line in PeriodicTaskAdmin:

date_hierarchy = 'start_time'

Admin Access URL:

The error appears when accessing:
http://localhost:3000/admin/django_celery_beat/periodictask/

Error Message:

user-defined function raised exception

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Additional Information:

1. Versions Used:

   • Django: 4.2
   • Django Celery Beat: v5.4.0
   • Celery: v5.4.0
   • Python: 3.12.8

2. Steps to Reproduce:

   1. Configure PeriodicTaskAdmin with the date_hierarchy attribute:

      class PeriodicTaskAdmin(admin.ModelAdmin):
          date_hierarchy = 'start_time'

   2. Navigate to the admin page:
      http://localhost:3000/admin/django_celery_beat/periodictask/.

3. Expected Behavior:
   The date_hierarchy field should work without raising exceptions.

4. Actual Behavior:
   The error mentioned above is triggered, and the admin page fails to load. If I comment out date_hierarchy, the page works as expected.

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Relevant Code:

File: admin.py

from django.contrib import admin
from django_celery_beat.models import PeriodicTask

class PeriodicTaskAdmin(admin.ModelAdmin):
    date_hierarchy = 'start_time'

admin.site.register(PeriodicTask, PeriodicTaskAdmin)

Template Line Causing Error:

{% block date_hierarchy %}{% if cl.date_hierarchy %}{% date_hierarchy cl %}{% endif %}{% endblock %}

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Notes:

If additional information or testing is required to identify the root cause of this issue, please let me know. I am happy to assist in debugging this further.