Use Custom Filter with Django ModelChoice Filter

Question

I am trying to create use the filter method with django-filters

See an example of the models below:

class Chicken(TimeStampedModel):
    eggs = ForeignKey(Egg)

class Egg(TimeStampedModel):
    hatched = BooleanField(default=False)

See an example of my current set up for the filter:

class ChickenFilter(FilterSet):
    eggs__contains = ModelChoiceFilter(name="eggs", method='hatched_eggs', queryset=Eggs.objects.all())

   def hatched_eggs(self, queryset, name, value):
      print "We got eggs"
     return queryset.filter(eggs__hatched=True)

The problem is that the method doesnt even print We got eggs when I hit the url. It just returns an empty queryset.

Answer 1

I did it like below:

In my urls I sent ?ids=1,2,3,4

class MyFilter(filters.FilterSet):
    ids = django_filters.CharFilter(method='ids__in')

    def ids__in(self, queryset, value, *args, **kwargs):
        try:
            if args:
                ids = args[0].split(',')
                ids = [int(_id) for _id in ids]
                queryset = queryset.filter(id__in=ids)
        except ValueError:
            pass
        return queryset

Answer 2

I was going through the same problem. My method was not being called.

So came to conclusion, I can make a workaround using:

Using custom methods in filter with django-rest-framework

class ChickenFilter(FilterSet):
    eggs__contains = CharFilter(action='hatched_eggs')

def hatched_eggs(queryset, value):
      print "We got eggs"
     if value:
         return queryset.filter(eggs__hatched=True)
     return queryset