Validate that URLConf modules contain a urlpatterns entry

[The Epic]

Hey everyone. I've seen a few people on Discord mention that Django reported circular imports due to their URL configs, and in at least one case the problem was that the user made a typo in urlpatterns.

I think it would be grand if Django checked for the existence of the urlpatterns attribute when passing a module to include and raised a clearer Exception if it is absent.

[David Sanders]

Hello,

Django already does this with:

django.core.exceptions.ImproperlyConfigured: The included URLconf '<module 'foo.urls' from '/path/to/foo/urls.py'>' does not appear to have any patterns in it. If you see the 'urlpatterns' variable with valid patterns in the file then the issue is probably caused by a circular import.

🤔

[The Epic]

Replying to David Sanders:

Hello,

Django already does this with:

django.core.exceptions.ImproperlyConfigured: The included URLconf '<module 'foo.urls' from '/path/to/foo/urls.py'>' does not appear to have any patterns in it. If you see the 'urlpatterns' variable with valid patterns in the file then the issue is probably caused by a circular import.

🤔

Oh, you're right. I guess the message should be clearer. I don't really see how circular imports would affect it.

[David Sanders]

Ok marking as worksforme… raise a discussion on the Django Forum if you'd like to discuss changing the message 👍