Question

我有2个与OneToOne相关的模型和模型是FK到第2个模型

models.py

class Legal(TimeStampedModel):
     name = models.CharField('Name', max_length=255, blank=True)

class LegalCard(TimeStampedModel):
    legal = models.OneToOneField('Legal', related_name='legal_card', on_delete=models.CASCADE)
    branch = models.ForeignKey('Branch', related_name='branch', null=True)
    post_address = models.CharField('Post address', max_length=255, blank=True)

class Branch(TimeStampedModel):
    name = models.CharField('Name',max_length=511)
    code = models.CharField('Code', max_length=6)

使用DRF我使它们表现为单一模型，因此我可以创建或更新两者：

serializer.py

class LegalSerializer(serializers.ModelSerializer):

    branch = serializers.IntegerField(source='legal_card.branch', allow_null=True, required=False)
    post_address = serializers.CharField(source='legal_card.post_address', allow_blank=True, required=False)

    class Meta:
        model = Legal
        fields = ('id',
                  'name',
                  'branch',
                  'post_address',
                  )
        depth = 2


    def create(self, validated_data):
        legal_card_data = validated_data.pop('legal_card', None)
        legal = super(LegalSerializer, self).create(validated_data)
        self.update_or_create_legal_card(legal, legal_card_data)
        return legal

    def update(self, instance, validated_data):
        legal_card_data = validated_data.pop('legal_card', None)
        self.update_or_create_legal_card(instance, legal_card_data)
        return super(LegalSerializer, self).update(instance, validated_data)

    def update_or_create_legal_card(self, legal, legal_card_data):
        LegalCard.objects.update_or_create(legal=legal, defaults=legal_card_data)

views.py

 class LegalDetailView(generics.RetrieveUpdateDestroyAPIView):
        queryset = Legal.objects.all()
        serializer_class = LegalSerializer

我试图通过将FK作为整数发送来保存它（我只想发布分支的id），但是我收到错误

ValueError: Cannot assign "2": "LegalCard.branch" must be a "Branch" instance.

有没有办法只传递分支的ID？

谢谢

Answer 1

在Django中，如果只需要FK值，则可以使用已经存在的对象上的FK值，而不是获取相关对象。假设您有一个ID为＆的法律和分支对象为1.然后您可以通过以下方式保存LegalCard对象：

LegalCard(legal_id=1,branch_id=1,post_address="Istanbul Street No:1")

Answer 2

只需使用legal_card.branch_id而不是legal_card.branch来获取id，而不是相关对象。而深度= 1

Django Rest Framework：在OneToOne模型中保存ForeignKey

2 个答案: