Django Rest Framework - Could not resolve URL for hyperlinked relationship using view name "user-detail"

Question

Because it's a HyperlinkedModelSerializer your serializer is trying to resolve the URL for the related User on your Bottle.
As you don't have the user detail view it can't do this. Hence the exception.

1. Would not just registering the UserViewSet with the router solve your issue?
2. You could define the user field on your BottleSerializer to explicitly use the UserSerializer rather than trying to resolve the URL. See the serializer docs on dealing with nested objects for that.

I came across this error too and solved it as follows:

The reason is I forgot giving "**-detail" (view_name, e.g.: user-detail) a namespace. So, Django Rest Framework could not find that view.

There is one app in my project, suppose that my project name is myproject, and the app name is myapp.

There is two urls.py file, one is myproject/urls.py and the other is myapp/urls.py. I give the app a namespace in myproject/urls.py, just like:

url(r'', include(myapp.urls, namespace="myapp")),

I registered the rest framework routers in myapp/urls.py, and then got this error.

My solution was to provide url with namespace explicitly:

class UserSerializer(serializers.HyperlinkedModelSerializer):
    url = serializers.HyperlinkedIdentityField(view_name="myapp:user-detail")

    class Meta:
        model = User
        fields = ('url', 'username')

And it solved my problem.

Maybe someone can have a look at this : http://www.django-rest-framework.org/api-guide/routers/

If using namespacing with hyperlinked serializers you'll also need to ensure that any view_name parameters on the serializers correctly reflect the namespace. For example:

urlpatterns = [
    url(r'^forgot-password/$', ForgotPasswordFormView.as_view()),
    url(r'^api/', include(router.urls, namespace='api')),
]

you'd need to include a parameter such as view_name='api:user-detail' for serializer fields hyperlinked to the user detail view.

class UserSerializer(serializers.HyperlinkedModelSerializer):
    url = serializers.HyperlinkedIdentityField(view_name="api:user-detail")

    class Meta:
        model = User
        fields = ('url', 'username')

Another nasty mistake that causes this error is having the base_name unnecessarily defined in your urls.py. For example:

router.register(r'{pathname}', views.{ViewName}ViewSet, base_name='pathname')

This will cause the error noted above. Get that base_name outta there and get back to a working API. The code below would fix the error. Hooray!

router.register(r'{pathname}', views.{ViewName}ViewSet)

However, you probably didn't just arbitrarily add the base_name, you might have done it because you defined a custom def get_queryset() for the View and so Django mandates that you add the base_name. In this case you'll need to explicitly define the 'url' as a HyperlinkedIdentityField for the serializer in question. Notice we are defining this HyperlinkedIdentityField ON THE SERIALIZER of the view that is throwing the error. If my error were "Could not resolve URL for hyperlinked relationship using view name "study-detail". You may have failed to include the related model in your API, or incorrectly configured the lookup_field attribute on this field." I could fix this with the following code.

My ModelViewSet (the custom get_queryset is why I had to add the base_name to the router.register() in the first place):

class StudyViewSet(viewsets.ModelViewSet):
    serializer_class = StudySerializer

    '''custom get_queryset'''
    def get_queryset(self):
        queryset = Study.objects.all()
        return queryset

My router registration for this ModelViewSet in urls.py:

router.register(r'studies', views.StudyViewSet, base_name='studies')

AND HERE'S WHERE THE MONEY IS! Then I could solve it like so:

class StudySerializer(serializers.HyperlinkedModelSerializer):
    url = serializers.HyperlinkedIdentityField(view_name="studies-detail")
    class Meta:
        model = Study
        fields = ('url', 'name', 'active', 'created',
              'time_zone', 'user', 'surveys')

Yep. You have to explicitly define this HyperlinkedIdentityField on itself for it to work. And you need to make sure that the view_name defined on the HyperlinkedIdentityField is the same as you defined on the base_name in urls.py with a '-detail' added after it.

This code should work, too.

class BottleSerializer(serializers.HyperlinkedModelSerializer):

  user = UserSerializer()

  class Meta:
    model = Bottle
    fields = ('url', 'wine', 'user')

Today, I got the same error and below changes rescue me.

Change

class BottleSerializer(serializers.HyperlinkedModelSerializer):

to:

 class BottleSerializer(serializers.ModelSerializer):

I ran into this error after adding namespace to my url

 url('api/v2/', include('api.urls', namespace='v2')),

and adding app_name to my urls.py

I resolved this by specifying NamespaceVersioning for my rest framework api in settings.py of my project

REST_FRAMEWORK = {
    'DEFAULT_VERSIONING_CLASS':'rest_framework.versioning.NamespaceVersioning'}