Django Tutorial: Generic Views. Attribute Error

Question

I'm at the last part of this tutorial.

from django.conf.urls import patterns, include, url
from django.views.generic import DetailView, ListView
from polls.models import Poll

urlpatterns = patterns('',
    url(r'^$',
        ListView.as_view(
            queryset=Poll.objects.order_by('-pub_date')[:5],
            context_object_name='latest_poll_list',
            template_name='polls/index.html')),
    url(r'^(?P<pk>\d+)/$',
        DetailView.as_view(
            model=Poll,
            template_name='polls/detail.html')),
    url(r'^(?P<pk>\d+)/results/$',
        DetailView.as_view(
            model=Poll,
            template_name='polls/results.html'),
        name='poll_results'),
    url(r'^(?P<poll_id>\d+)/vote/$', 'polls.views.vote'),
)

The ListView works, but when I visit a url with DetailView, I get.

AttributeError at /polls/2/
Generic detail view DetailView must be called with either an object pk or a slug.
Request Method: GET
Request URL:    http://127.0.0.1:8000/polls/2/
Django Version: 1.4.1
Exception Type: AttributeError
Exception Value:    
Generic detail view DetailView must be called with either an object pk or a slug.
Exception Location: /home/yasith/coding/django/django-tutorial/lib/python2.7/site-packages/django/views/generic/detail.py in get_object, line 46
Python Executable:  /home/yasith/coding/django/django-tutorial/bin/python2
Python Version: 2.7.3

I'm not sure what I'm doing wrong. Any help would be appreciated.

EDIT: Add the main urls.py

from django.conf.urls import patterns, include, url

from django.contrib import admin
admin.autodiscover()

urlpatterns = patterns('',
    url(r'^polls/', include('polls.urls')),
    url(r'^admin/', include(admin.site.urls)),
)

Answer 1

I think the code you posted above, is not the one you have on your disk.

I had the same problem, but then I looked carefully at both, my code and the tutorial. The regex I had in my code was different from the tutorial.

This was my code:

 url(r'^(?P<poll_id>\d+)/$',-$                                               
 url(r'^(?P<poll_id>\d+)/results/$',-$                                       

This is the correct core:

 url(r'^(?P<pk>\d+)/$',-$                                               
 url(r'^(?P<pk>\d+)/results/$',-$                                       

Note that *poll_id* was in the previous sections of the tutorial, but generic views require pk. Also note that the tutorial is correct, and you posted the correct code (from the tutorial.)