Django REST framework object level permissions

Question

I am using Django REST Framework to access a resource \'user\'.

As user information is personal, I do not want a GET request to list every user on the system, UNLESS the

Answer 1

I have a similar need. Lets call my app x. Here's what I came up with.

First, put this in x/viewsets.py:

# viewsets.py
from rest_framework import mixins, viewsets

class DetailViewSet(
  mixins.CreateModelMixin,
  mixins.RetrieveModelMixin,
  mixins.UpdateModelMixin,
  mixins.DestroyModelMixin,
  viewsets.GenericViewSet):
    pass

class ReadOnlyDetailViewSet(
  mixins.RetrieveModelMixin,
  viewsets.GenericViewSet):
    pass

class ListViewSet(
  mixins.ListModelMixin,
  viewsets.GenericViewSet):
    pass

Then in x/permissions.py:

# permissions.py
from rest_framework import permissions

class UserIsOwnerOrAdmin(permissions.BasePermission):
    def has_permission(self, request, view):
        return request.user and request.user.is_authenticated()

    def check_object_permission(self, user, obj):
        return (user and user.is_authenticated() and
          (user.is_staff or obj == user))

    def has_object_permission(self, request, view, obj):
        return self.check_object_permission(request.user, obj)

Then in x/views.py:

# views.py
from x.viewsets import DetailViewSet, ListViewSet
from rest_framework import permissions

class UserDetailViewSet(DetailViewSet):
    queryset = User.objects.all()
    serializer_class = UserDetailSerializer
    permission_classes = (UserIsOwnerOrAdmin,)

class UserViewSet(ListViewSet):
    queryset = User.objects.all()
    serializer_class = UserSerializer
    permission_classes (permissions.IsAdminUser,)

By the way, notice that you can use a different serializer for those two viewsets, which means you can show different attributes in the list view than in the retrieve view! For example:

# serializers.py
class UserSerializer(serializers.HyperlinkedModelSerializer):
    class Meta:
        model = User
        fields = ('username', 'url',)

class UserDetailSerializer(serializers.HyperlinkedModelSerializer):
    class Meta:
        model = User
        fields = ('url', 'username', 'groups', 'profile', 'password',)
        write_only_fields = ('password',)

Then in x/urls.py:

# urls.py
from x import views
from rest_framework import routers

router = routers.DefaultRouter()
router.register(r'users', views.UserViewSet)
router.register(r'users', views.UserDetailViewSet)

...

I was mildly surprised that router accepted the same pattern twice, but it does appear to work.

Caveat lector: I've confirmed this all works via the API browser, but I haven't tried updating via the API yet.