How do you use pagination in a Django REST framework ViewSet subclass?

Question

I have a simple subclass of viewsets.ViewSet which looks like:

from rest_framework import viewsets
from rest_framework.response import Response

from ..models import Entry, Sitting, Source, Venue
from .serializers import (
    SittingSerializer, SittingWithEntriesSerializer,
)

class SittingViewSet(viewsets.ViewSet):

    def list(self, request, version=None):
        queryset = Sitting.objects.order_by('id')
        serializer = SittingSerializer(
            queryset, many=True, context={'request': request}
        )
        return Response(serializer.data)

    def retrieve(self, request, pk=None, version=None):
        prefetch_qs = Entry.objects.select_related('speaker')
        queryset = Sitting.objects.order_by('id') \
            .prefetch_related(Prefetch('entry_set', queryset=prefetch_qs))
        sitting = get_object_or_404(queryset, pk=pk)
        serializer = SittingWithEntriesSerializer(
            sitting, context={'request': request}
        )
        return Response(serializer.data)

However, the list view isn't paginated, as it is if you use a subclass of ModelViewSet. The settings I'm using are:

# Django Rest Framework settings:
REST_FRAMEWORK = {
    'DEFAULT_PERMISSION_CLASSES': ('pombola.api.permissions.ReadOnly',),
    'DEFAULT_VERSIONING_CLASS': 'rest_framework.versioning.URLPathVersioning',
    'PAGE_SIZE': 10,
}

The documentation suggests looking at the source code for the mixins.ListModelMixin and generics.GenericAPIView classes, but I can't easily see how to reapply what they do to paginate results to these ViewSet methods.

Could anyone suggest what the simplest way would be to change this example to get pagination for the list view?

Answer 1

You overrided the list method, so it doesnt paginate your data.
If you check ListModelMixins I think this might be your answer:

class SittingViewSet(
    viewsets.GenericViewSet,
    mixins.ListModelMixin,
    mixins.RetrieveModelMixin):

    def list(self, request, *args, **kwargs):
        queryset = self.filter_queryset(
            Sitting.objects.order_by('id')
        )

        page = self.paginate_queryset(queryset)
        if page is not None:
            serializer = SittingSerializer(
                page, 
                many=True, 
                context={'request': request}
                )
            return self.get_paginated_response(serializer.data)

        serializer = SittingSerializer(
                queryset, 
                many=True, 
                context={'request': request}
                )
        return Response(serializer.data)

Answer 2

Simple solution. Let's use the auth model as an example.

from django.contrib.auth.models import User

from rest_framework.pagination import PageNumberPagination
from rest_framework import viewsets

from .serializer import UserSerializer


class UserViewSet(viewsets.ViewSet):
    def list(self, request):
        queryset = User.objects.all()
        pagination = PageNumberPagination()
        qs = pagination.paginate_queryset(queryset, request)
        serializer = UserSerializer(qs, many=True)
        return pagination.get_paginated_response(serializer.data)