Putting if else conditions in Django Rest Framework API View while searching

Question

I was writing API with DRF and what I want is to change queryset, if the search will return no results.

from rest_framework.generics import ListAPIView
from rest_framework import filters
from .models import Item
from .serializer import ItemSerializer
from .pagination import ItemPagination

class SearchItemApi(ListAPIView):
    serializer_class = ItemSerializer
    filter_backends = [filters.SearchFilter]
    search_fields =  ['name',]
    pagination_class = ItemPagination
    
    def get_queryset(self): 
        return Item.objects.all()

Here is the serializer:

class ItemSerializer(serializers.ModelSerializer):
    class Meta:
        model = Item
        fields = ('id', 'name',)

And this APIView will show these results on the page:

{
    "count": 2,
    "next": null,
    "previous": null,
    "results": [
        {
            "id": 1,
            "name": "Blue Jeans",
        },
        {
            "id": 2,
            "name": "Red Jeans",
        }
    ]
}

And I want to make something like this:

def get_queryset(self):
    if api_data["count"] == 0:
         return Item.objects.filter(*some filter*)
    else:
         return Item.objects.all()

How can I add a condition to return other queryset, if the search will bring zero results?

Answer 1

You need to check the queryset result

def get_queryset(self):
    qs = super().get_queryset()
    if qs.count() == 0:
         return Item.objects.filter(*some filter*)
    else:
         return Item.objects.all()