如何在一個 DRF 端點中保存三個相關模型？

Question

我有 4 個相關模型，我需要實現功能以在一次后查詢中在數據庫中一致地創建這些模型的實例。 為此，我使用 APIView 類 post 方法的覆蓋。

楷模

class VendorContacts(models.Model):
    contact_id = models.AutoField(primary_key=True)
    vendor = models.OneToOneField('Vendors', on_delete=models.CASCADE)
    contact_name = models.CharField(max_length=45, blank=True)
    phone = models.CharField(max_length=45, blank=True)
    email = models.CharField(max_length=80, blank=True, unique=True)

    class Meta:
        db_table = 'vendor_contacts'


class VendorModuleNames(models.Model):
    vendor = models.OneToOneField('Vendors', on_delete=models.CASCADE, primary_key=True)
    module = models.ForeignKey(Modules, models.DO_NOTHING)
    timestamp = models.DateTimeField(auto_now=True)

    class Meta:
        db_table = 'vendor_module_names'
        unique_together = (('vendor', 'module'),)


class Vendors(models.Model):
    COUNTRY_CHOICES = tuple(COUNTRIES)

    vendorid = models.AutoField(primary_key=True)
    vendor_name = models.CharField(max_length=45, unique=True)
    country = models.CharField(max_length=45, choices=COUNTRY_CHOICES)
    nda = models.DateField(blank=True, null=True)
    user_id = models.ForeignKey('c_users.CustomUser', on_delete=models.PROTECT)
    timestamp = models.DateTimeField(auto_now_add=True)

    class Meta:
        db_table = 'vendors'
        unique_together = (('vendorid', 'timestamp'),)

class Modules(models.Model):
    MODULES_NAME =tuple(MODULES)
    mid = models.AutoField(primary_key=True)
    module_name = models.CharField(max_length=50, choices=MODULES_NAME)
    active = models.BooleanField(default=True)
    timestamp = models.DateTimeField(auto_now=True)

    class Meta:
        db_table = 'modules'
        unique_together = (('mid', 'timestamp'),)

序列化程序.py

class VendorsSerializer(serializers.ModelSerializer):
    class Meta:
        model = Vendors
        fields = ('vendor_name',
                  'country',
                  'nda',)


class VendorContactSerializer(serializers.ModelSerializer):
    class Meta:
        model = VendorContacts
        fields = (
                  'contact_name',
                  'phone',
                  'email',)


class VendorModulSerializer(serializers.ModelSerializer):
    class Meta:
        model = VendorModuleNames
        fields = ('module',)


class ModulesSerializer(serializers.ModelSerializer):
    class Meta:
        model = Modules
        fields = ('module_name', )

視圖.py

class VendorsCreateView(APIView):
    """Create new vendor instances from form"""

    def post(self, request, *args, **kwargs):
        vendor_serializer = VendorsSerializer(data=request.data)
        vendor_contact_serializer = VendorContactSerializer(data=request.data)
        vendor_modules_serializer = VendorModulSerializer(data=request.data)
        module_serializer = ModulesSerializer(data=request.data)
        try:
            vendor_serializer.is_valid(raise_exception=True) \
                and vendor_contact_serializer.is_valid(raise_exception=True) \
                and vendor_modules_serializer.is_valid(raise_exception=True) \
                and module_serializer.is_valid(raise_exception=True)
            vendor_serializer.save(user_id=request.user)
            # ....
            # Some new logic here ????
            # ...
        except ValidationError:
            return Response({"errors": (vendor_serializer.errors,
                                        vendor_contact_serializer.errors,
                                        vendor_modules_serializer.errors
                                        )},
                            status=status.HTTP_400_BAD_REQUEST)
        else:
            return Response(request.data, status=status.HTTP_200_OK)

保存一個 Vendor 模型沒有問題，但我無法想象如何在單個請求中保存級聯所有相關模型。

Answer 1

save返回新保存的對象，然后您可以將其傳遞給后續的save()方法：

vendor = vendor_serializer.save(user_id=request.user)
module = module_serializer.save()
vendor_module = vendor_modules_serializer.save(module=module, vendor=vendor)
vendor_contact = vendor_contact_serializer.save(vendor=vendor)