Foreign key filter in a child object - sql

Question

I have the models:
class Boss(models.Model):
fullname = models.TextField()
class Shop(models.Model):
name = models.TextField()
address = models.TextField()
phone = models.TextField()
boss = models.ForeignKey(
Boss, on_delete=models.CASCADE, related_name="shops"
)
class Employee(models.Model):
name = models.TextField()
phone = models.TextField()
shop = models.ForeignKey(
Shop, on_delete=models.CASCADE, related_name="employees"
)
class WorkSpace(models.Model):
name = models.TextField()
employee = models.ForeignKey(
Shop, on_delete=models.CASCADE, related_name="work_spaces"
)
Serializers:
class WorkSpaceSerializer(serializers.ModelSerializer):
class Meta:
model = WorkSpace
fields = ["id","type"]
class EmployeeSerializer(serializers.ModelSerializer):
work_spaces = WorkSpaceSerializer(many=True, read_only=True)
class Meta:
model = Employee
fields = ["id","work_spaces","name","phone"]
class ShopSerializer(serializers.ModelSerializer):
employees = EmployeeSerializer(many=True, read_only=True)
class Meta:
model = Shop
fields = ["id","employees","phone","name","address"]
class BossSerializer(serializers.ModelSerializer):
shops = ShopSerializer(many=True, read_only=True)
class Meta:
model = Boss
fields = ["id","fullname","shops"]
View
class BossListView(
ListModelMixin,
GenericViewSet,
):
queryset = Boss.objects.all()
serializer_class = BossSerializer
permission_classes = [IsAuthenticated]
def get_queryset(self):
workspace_type = self.request.query_params.get("workspace_type")
qs = super().get_queryset()
if workspace_type:
qs = qs.filter(shops__employees__work_spaces__type=workspace_type).distinct()
return qs
I filtered with
Boss.objects.filter(shops__employees__work_spaces__type=C1)
and got:
{
"shops": [
{
"id": 32,
"name": "Garden flowers",
"address": "5 st. Hool-Maa",
"phone": "879124851861598",
"employees": [
{
"id": 150,
"name": "Mike",
"phone": "8154451246",
"work_spaces": [
{
"id": 497,
"type": "B12"
},
{
"id": 15,
"type": "Z5"
},
{
"id": 33,
"type": "C1"
}
]
}
]
}
]
}
But I only need C1 from work_spaces:
[{
"id": 33,
"type": "C1"
}]
How can I exclude other work_spaces from the queryset or do I need to convert the result to a list and then filter using a for loop? There can be many workspaces, and I don't need to show them all to the user, I need information about the Boss, the Shop, the Employee..

Answer 1

According to your view, you are applying the lower() method on the workspace_type.
So if you have workspace_type=C1, applying lower() will make workspace_type=c1, and your filter won't match any record.
I make here the assumption that your values have a capital letter.