id	summary	reporter	owner	description	type	status	component	version	severity	resolution	keywords	cc	stage	has_patch	needs_docs	needs_tests	needs_better_patch	easy	ui_ux
18674	Session app triggers an AttributeError	loic@…	nobody	"I suspect this occurs when session has expired, or something similar and may be related to a change of API in django 1.4:
{{{
AttributeError at / 
'QuerySet' object has no attribute '_prefetch_related_lookups'

Environment:

Request Method: GET

Django Version: 1.4
Python Version: 2.7.3
Installed Applications:
('django.contrib.auth',
 'django.contrib.contenttypes',
 'django.contrib.sessions',
 'django.contrib.sites',
 'django.contrib.messages',
 'django.contrib.staticfiles',
 'xxx'
 'django.contrib.admin')
Installed Middleware:
('django.middleware.common.CommonMiddleware',
 'django.contrib.sessions.middleware.SessionMiddleware',
 'django.middleware.csrf.CsrfViewMiddleware',
 'django.contrib.auth.middleware.AuthenticationMiddleware',
 'django.contrib.messages.middleware.MessageMiddleware')


Traceback:
File ""xxx/Django/django/core/handlers/base.py"" in get_response
  188.                 response = middleware_method(request, response)
File ""xxx/Django/django/contrib/sessions/middleware.py"" in process_response
  36.                 request.session.save()
File ""xxx/Django/django/contrib/sessions/backends/db.py"" in save
  52.             session_data=self.encode(self._get_session(no_load=must_create)),
File ""xxx/Django/django/contrib/sessions/backends/base.py"" in encode
  79.         pickled = pickle.dumps(session_dict, pickle.HIGHEST_PROTOCOL)
File ""xxx/Django/django/db/models/query.py"" in __getstate__
  65.         len(self)
File ""xxx/Django/django/db/models/query.py"" in __len__
  88.         if self._prefetch_related_lookups and not self._prefetch_done:

Exception Type: AttributeError at /
Exception Value: 'QuerySet' object has no attribute '_prefetch_related_lookups'
}}}
DB is MySQL."	Bug	closed	contrib.sessions	1.4	Normal	invalid			Unreviewed	0	0	0	0	0	0