Question

我正在尝试在Django Rest Framework中创建可写的嵌套序列化程序。但是我收到验证错误：slug是必需的。但这是外键，在插入父对象之前未知。

这是我的模型和序列化器：

型号：

class Letter(BaseModel):
    char = models.CharField(
        max_length=1,
    )
    slug = models.ForeignKey(
        to="core.LetterSlug",
        related_name="letters",
        on_delete=models.CASCADE,
    )


class LetterSlug(BaseModel):
    char = models.CharField(
        max_length=1,
    )

序列化器：

class LetterSerializer(serializers.ModelSerializer):
    class Meta:
        model = Letter
        fields = '__all__'


class LetterSlugSerializer(serializers.ModelSerializer):
    letters = LetterSerializer(many=True,instance=Letter.objects.all())

    class Meta:
        model = LetterSlug
        fields = ('char', 'letters')

    def create(self, validated_data):
        letter_data = validated_data.pop('letters')
        slug = LetterSlug.objects.create(**validated_data)
        Letter.objects.create(slug=slug, **letter_data)

        return slug

我希望它向新创建的Letter对象添加几个LetterSlug对象，这些对象共享相同的外键。

我尝试注释掉create方法的内容，并确保它在验证过程中，然后再调用create方法。

Answer 1

只需在LetterSerializer中将子弹设为只读：

class LetterSerializer(serializers.ModelSerializer):
    class Meta:
        model = Letter
        fields = '__all__'
        read_only_fields = ("slug", )

还如下编辑您的其他序列化器：

class LetterSlugSerializer(serializers.ModelSerializer):
    letters = LetterSerializer(many=True)

    class Meta:
        model = LetterSlug
        fields = ('char', 'letters')

    def create(self, validated_data):
        letters_data = validated_data.pop('letters')
        slug = super().create(**validated_data)
        Letter.objects.bulk_create([ Letter(slug=slug, **letter) for letter in letters_data ])
        return slug

Django Rest Framework上的可写嵌套序列化程序在嵌套外键上验证错误。必填项

1 个答案: