Django serializers filter foreignkey - django

Question

view:
class MPNView(viewsets.ModelViewSet):
queryset = MPN.objects.all()
serializer_class = MPNSerializer
serializers:
class ProductsSerializer(serializers.ModelSerializer):
class Meta:
model = Products
fields = "__all__"
class MPNSerializer(serializers.ModelSerializer):
products = ProductsSerializer(many=True)
class Meta:
model = MPN
fields = "__all__"
model:
class MPN(Model):
number = models.CharField(max_length=50)
created_at = models.DateTimeField(auto_now_add=True)
class Product(Model):
mpn = models.ForeignKey(to=MPN, on_delete=models.CASCADE, related_name="products", null=True, blank=True)
created_at = models.DateTimeField(auto_now_add=True)
Results i am getting:
[
{
"id": 1221,
"products": [],
"number": "B07BMTYSMR",
"created_at": "2020-09-29T03:05:01.560801Z"
},
{
"id": 1222,
"products": [
{
"id": 2352,
"created_at": "2020-09-30T12:49:09.347655Z",
},
{
"id": 2352,
"created_at": "2020-09-30T12:49:09.347655Z",
}
]
}
]
Results i am expecting:
[
{
"id": 1222,
"products": [
{
"id": 2352,
"created_at": "2020-09-30T12:49:09.347655Z",
},
{
"id": 2352,
"created_at": "2020-09-30T12:49:09.347655Z",
}
]
}
]
Here is my code . I have shared view, model and serializers.
Here I am trying to get result with ForeignKey related fields.
But, I want to add one filter so that it ignores data where products is [ ] (empty array)
Please have a look how can I achieve that.

Answer 1

Try filtering the queryset:
queryset = MPN.objects.all().exclude(products__isnull=True)
Here you would use the "products" and check if it is empty. Empty results would be excluded.