Django REST framework RetrieveAPIView gets empty "id" parameter and returns 404 error - django

Question

I use Django 1.11 + Django REST Framework. I'm trying to get detailed data about distinct record using generic RetrieveAPIView from Django REST Framework and server returns "HTTP 404 Not Found" result, i.e. no data.
models.py file:
class TestPage( models.Model):
title = models.CharField( size = 120)
counter = models.IntegerField( default = 0)
def __unicode__(self):
return u'' + self.title
serializers.py file:
class TestPageSerializer(serializers.ModelSerializer):
class Meta:
fields = ('id', 'title', 'counter',)
model = models.TestPage
urls.py file:
urlpatterns = [
url( r'^admin/', admin.site.urls),
url( r'^api/', include( 'rest_framework.urls')),
url( r'^api/', include( 'testpages.urls')),
]
testpages/urls.py file:
urlpatterns = [
url( r'^$', views.TestPageList.as_view()),
url( r'^(?P<id>)\d+/$', views.TestPageDetail.as_view()),
]
and at last views.py file:
class TestPageList(generics.ListAPIView):
lookup_field = 'id'
queryset = TestPage.objects.all()
serializer_class = TestPageSerializer
class TestPageDetail(generics.RetrieveAPIView):
lookup_field = 'id'
queryset = TestPage.objects.all()
serializer_class = TestPageSerializer
# def get_object( self):
# print self.kwargs
If I request "http://127.0.0.1:8000/api/" for all records in the list, server returns all records. But if I want to get record by id using "http://127.0.0.1:8000/api/1/" for example, I get the empty result like in the photo below.
[![enter image description here][1]][1]
If I uncomment get_object()-function in last 2 lines, I can see {'id': u''} in terminal i.e. server gets empty parameter 'id'.
What wrong with this code?

Answer 1

The issue is your regular expression matching for id, you're putting \d+ outside of the matching group when it's actually what you want to match:
url(r'^(?P<id>\d+)/$', views.TestPageDetail.as_view())
By the way, to be good REST citizen, you shouldn't add the / at the end of a URL for a specific object.
Note: As mentioned by JPG, adding a name for the resource you're fetching (plural) would be proper RESTful:
url(r'^pages/(?P<id>\d+)$', views.TestPageDetail.as_view())
This way, you fetch page nr. 1 at /api/pages/1

Answer 2

The original problem was the closing parathesis (the regex expression), you were misplaced that.
urlpatterns = [
url(r'^$', views.TestPageList.as_view()),
url(r'^(?P<id>\d+)/$', views.TestPageDetail.as_view()),
^^^ here
]
Apart from that, You should change the urls patterns to a sensible form, as
#testpages/urls.py
urlpatterns = [
url(r'^test/$', views.TestPageList.as_view()),
url(r'^test/(?P<id>\d+)/$', views.TestPageDetail.as_view()),
]
then the list-api will be available on /api/test/ endpoint and the detail-api will be available on /api/test/{id}/