Getting the “str” has no property “_default_manager” on a Django app just on startup

Question

Right after I restart Apache to pick up the new Django changes, I get the following errors for probably 30 seconds to a minute afterwards:

ViewDoesNotExist: Tr

Answer 1

I think it's this bug:

http://code.djangoproject.com/ticket/10405#comment:11

Seems like a perfect fit considering google searches don't show much else, and that your problem goes away after some time - according to this ticket due to lazy loading of model strings.

The comment suggests adding the following before your admin autodiscover function.

from django.db.models.loading import cache as model_cache
if not model_cache.loaded:
    model_cache.get_models()