嵌套可写序列化程序上的验证错误

Question

我有一个像这样的可写嵌套序列化器 -

class AddressSerializer(serializers.ModelSerializer):
    class Meta:
        model = publicAddress
        fields = "__all__"


class customerSerializer(serializers.ModelSerializer):
    publicAdd = AddressSerializer(many=True)
        class Meta:
        model = customerMaster
        fields = ['id','publicAdd']

    def create(self, validated_data):
        Address = validated_data.pop('publicAdd')
        customer = customerMaster.objects.create(**validated_data)
        for addres in Address:
            publicAddress.objects.create(customer=customer, **addres)
        return customer

这一切正常，直到我应用验证，例如

class AddressSerializer(serializers.ModelSerializer):
    class Meta:
        model = publicAddress
        fields = "__all__"
        validators = [
            UniqueTogetherValidator(
                queryset=publicAddress.objects.all(),
                fields=['customer', 'someValue']
            )
        ]

定义

read_only_fields = ('customer',)

在 AddressSerializer 中也无济于事。

现在它会抛出一个错误，例如 cust 字段始终是必需的，并通过 api 发送 cust 值。

关于如何验证这一点没有错误的任何帮助？

Answer 1

customer 是一个只读字段。这意味着DRF 仅在创建对象后将其用于响应。但在UniqueTogetherValidator 中，它需要数据才能创建它。

正如DRF 在文档中所说：

UniqueTogetherValidator 类总是强加一个隐式约束，它所应用的所有字段总是按要求处理。具有默认值的字段是一个例外，因为即使在用户输入中省略时，它们也始终提供一个值。

所以需要手动处理：

class customerSerializer(serializers.ModelSerializer):
    publicAdd = AddressSerializer(many=True)

    class Meta:
        model = customerMaster
        fields = ['id','publicAdd']

    def create(self, validated_data):
        Address = validated_data.pop('publicAdd')
        customer = customerMaster.objects.create(**validated_data)
        for addres in Address:
           publicAddress.objects.create(customer=customer, **addres)
        return customer

    def validate(self, attrs):
        # customer is not in attrs because it's read-only
        # Maybe you need to add context data to your serializer or get it somehow you know
        object_exists = publicAddress.objects.filter(
            customer=your_customer, someValue=attrs["someValue"]
        ).exists()
        if object_exists:
            raise serializer.ValidationError("Duplicate object")
        return attrs