Pass url argument to ListView queryset

Question

models.py

class Lab(Model):
    acronym = CharField(max_length=10)

class Message(Model):
    lab = ForeignKey(Lab)

Answer 1

class CustomListView(ListView):
    model = Message

    def get(self, request, *args, **kwagrs):
        # either
        self.object_list = self.get_queryset()
        self.object_list = self.object_list.filter(lab__acronym=kwargs['lab'])

        # or
        queryset = Lab.objects.filter(acronym=kwargs['lab'])
        if queryset.exists():
            self.object_list = self.object_list.filter(lab__acronym=kwargs['lab'])
        else:
            raise Http404("No lab found for this acronym")

        # in both cases
        context = self.get_context_data()
        return self.render_to_response(context)