Django rest nested child serializer (having reverse relation) list creation

Question

I am new to django rest and currently working on serializers to handle nested creation of objects ModelB is the object whose instance is to be created and it has a reverse relation with modelC and has a direct relation with modelA

ModelA has to fetched and passed to ModelB during its creation ModelC list is to be created alongwith ModelB

Models

class ModelA(TimeStampMixin, CoordinateMixin):
    name = models.CharField(max_length=150)


class ModelB(TimeStampMixin):
    uuid = models.UUIDField(default=uuid.uuid4, editable=False, unique=True)
    modelA = models.ForeignKey(
        ModelA,
        on_delete=models.PROTECT,
        related_name='modela_reverse'
    )



class ModelC(TimeStampMixin):
    uuid = models.UUIDField(default=uuid.uuid4, editable=False, unique=True)
    modelB = models.ForeignKey(ModelB, on_delete=models.CASCADE, related_name='modelb_reverse')
    modelD = models.ForeignKey(ModelD, on_delete=models.CASCADE, related_name='modelD_reverse')
    
class ModelD(TimeStampMixin):

    uuid = models.UUIDField(default=uuid.uuid4, editable=False, unique=True)
    name = models.CharField(max_length=50)

Serializers:

class ModelDSerializer(serializers.ModelSerializer):
 
    class Meta:
        model = ModelD
        fields = ['name', 'uuid']
 

class ModelCSerializer(serializers.ModelSerializer):
    modeld = ModelDSerializer(many=False)

    class Meta:
        model = ModelC
        fields = ['modeld', 'quantity']


class ModelA(serializers.ModelSerializer):
    class Meta:
        model = ModelA
        fields = ['name', 'uuid']
        read_only_fields = ['name']

    def to_internal_value(self, data):
        modelA = ModelA.objects.get(**data)
        return modelA


class ModelB(serializers.ModelSerializer):    
     modelb_reverse = ModelCSerializer(many=True)
     modelA = ModelASerializer(many=False)

    class Meta:
        model = ModelB
        fields = ['modelb_reverse', 'modelA']

Uptil now i have been able to carry the creation of ModelB through its serializer when only nested modelA is included but i am stuck at somehow modifying the solution to include the creation of reverse objects through the nested ModelCSerializer

I am finding an elegant way to achieve this and have been stuck here for a while Would really appreciate some help Thanks in advance

You can use drf-writable-nested mixins to create child entities. — Harun Yilmaz

adnan kaya adnan kaya · Accepted Answer · 2020-09-11T11:15:02

You can override create method of ModelB serializer to create reverse objects. Chek this out : https://www.django-rest-framework.org/api-guide/relations/#writable-nested-serializers

Django rest nested child serializer (having reverse relation) list creation

1 Answers