[FIXED] django-filter use paginations

Issue

I'm using the django-filter package to provide a search functionality on my List View.

Now I want to add a pagination to that view as well.
I'm trying to combine pagination to a filtered queryset, but I have no clue on how to go on.

So far, I have tried the following on views.py:

def search(request):
    qs = local_url.objects.filter(global_url__id=1).all()
    paginator = Paginator(qs, 25)
    page = request.GET.get('page')
    try:
        pub = paginator.page(page)
    except PageNotAnInteger:
        pub = paginator.page(1)
    except EmptyPage:
       pub = paginator.page(paginator.num_pages)
    url_filter = PublicationFilter(request.GET, queryset=qs)
    return render(request, 'ingester/search_list.html', {'filter': url_filter, 'publication':pub})

Solution

To use Django Filter and paginate the filtered result you can do the following:

1. Create a filter class for your model:

   On my_project/my_app/filters.py:

   import django_filters
   
   class MyModelFilter(django_filters.FilterSet):
       class Meta:
           model = MyModel
           # Declare all your model fields by which you will filter
           # your queryset here:
           fields = ['field_1', 'field_2', ...]
   

2. Every FilterSet object has a .qs property which contains the filtered queryset and you can even override it if you want.

3. We will paginate the .qs property of our MyModelFilter:

   On my_project/my_app/views.py:

   from . import filters
   from django.core.paginator import Paginator, EmptyPage, PageNotAnInteger
   
   def my_view(request):
       # BTW you do not need .all() after a .filter() 
       # local_url.objects.filter(global_url__id=1) will do
       filtered_qs = filters.MyModelFilter(
                         request.GET, 
                         queryset=MyModel.objects.all()
                     ).qs
       paginator = Paginator(filtered_qs, YOUR_PAGE_SIZE)
   
       page = request.GET.get('page')
       try:
           response = paginator.page(page)
       except PageNotAnInteger:
           response = paginator.page(1)
       except EmptyPage:
           response = paginator.page(paginator.num_pages)
   
       return render(
           request, 
           'your_template.html', 
           {'response': response}
       )
   

And there you have it!

---

PS_1: Django filter in my experience, "plays" better with Django Rest Framework.

PS_2: If you are about to utilize DRF, I have written an example on how to use pagination in a function based view which you can easily combine with a FilterSet:

@api_view(['GET',])
def my_function_based_list_view(request):
    paginator = PageNumberPagination()
    filtered_set = filters.MyModelFilter(
                       request.GET, 
                       queryset=MyModel.objects.all()
                   ).qs
    context = paginator.paginate_queryset(filtered_set, request)
    serializer = MyModelSerializer(context, many=True)
    return paginator.get_paginated_response(serializer.data)

Answered By - John Moutafis