custom pagination not woking in apiview of Django rest - django

Question

I have a custom pagination class in a separate file and until now I have been importing it in a ListAPIView, but this time I tried with APIView, but it didn't work.
My pagination class:
class CustomPagination(PageNumberPagination):
def get_paginated_response(self, data):
return Response({
'links': {
'next': self.get_next_link(),
'previous': self.get_previous_link()
},
'count': self.page.paginator.count,
'page_size' : 15,
'results': data
})
I am trying to use custom pagination because I can have the count of the objects as well.
My view where I try to implement the pagination:
from apps.products.api.pagination import CustomPagination
class CouponView(APIView):
permission_classes = [AllowAny]
#pagination_class = CustomPagination
def get(self,request,pk = None,*args,**kwargs):
id = pk
if id is not None:
abc = Coupons.objects.get(id=id)
serializer = CouponSerializer(abc)
return serializer.data
else:
abc = Coupons.objects.all()
paginator = CustomPagination()
result_page = paginator.paginate_queryset(abc, request)
serializer = CouponSerializer(result_page,many=True)
return Response (serializer.data,status=status.HTTP_200_OK)

Answer 1

APIView doesn't support this feature. You'll either need to leverage ListApiView or similar generics (such as RetrieveApiView), or use the ReadOnlyModelViewSet. These both support pagination, and give you get_object.
Your code seems to be implementing the basic ViewSet features (list + retrieve). The issue with the API views is that these two both use get, so they can't be combined into one view. Using a viewset will solve that.
class CouponReadOnly(ReadOnlyModelViewSet):
pagination_class = SomeClass
serializer_class = CouponSerializer
queryset = Coupon.objects.all()
And then use a Router in your urls.py to link it up, and let the router generate the routes.
# in your urls.py --------------
router = SimpleRouter()
router.register("coupons", CouponReadOnly, "coupon")
urlpatterns = [...] # existing routes
urlpatterns += router.urls
If you want to do this manually with 2 views, then you can use the generics and manually create the paths, like you already are:
class CouponListView(ListAPIView):
# you said this one already works
class CouponGetView(RetrieveAPIView):
queryset = Coupon.objects.all()
serializer_class = CouponSerializer
urlpatterns = [
path("coupons/", CouponListView.as_view(), name="coupon-list"),
path("coupons/<int:pk>", CouponGetView.as_view(), name="coupon-get"),
]

Answer 2

You should use get_paginated_response in GenericAPIView for custom pagination.
from apps.products.api.pagination import CustomPagination
from rest_framework.generics import GenericAPIView
class CouponView(GenericAPIView):
permission_classes = [AllowAny]
def get(self,request,pk = None,*args,**kwargs):
id = pk
if id is not None:
abc = Coupons.objects.get(id=id)
serializer = CouponSerializer(abc)
return serializer.data
else:
abc = Coupons.objects.all()
self.pagination_class = CustomPagination
page = self.paginate_queryset(abc)
serializer = serializer(page, many=True, context={'request': request})
return self.get_paginated_response(serializer.data)
However, let apply the correct RESTFul API to get list and detail, so you will not custom more.
List coupons: GET /api/coupons/
Get coupon detail: GET /api/coupons/<coupon_id/
class CouponView(ListAPIView, RetrieveAPIView):
permission_classes = [AllowAny]
pagination_class = CustomPagination
queryset = Coupons.objects.all()
serializer_class = CouponSerializer

Answer 3

I did the following and it worked:
def get(self,request,pk = None,*args,**kwargs):
id = pk
if id is not None:
abc = Coupons.objects.get(id=id)
serializer = CouponSerializer(abc)
return serializer.data
else:
abc = Coupons.objects.all()
paginator = CustomPagination()
result_page = paginator.paginate_queryset(abc,request)
serializer = CouponSerializer(result_page,many=True)
# return Response (serializer.data,status=status.HTTP_200_OK)
return paginator.get_paginated_response(serializer.data)