python - Factory Boy 与 Django ManyToMany 模型

Question

我在同一模块上有 3 个模型，app.models.py ，如下。其他一些模型可能会出现在代码中，但并不相关。

可选

class Optional(models.Model):
    name = models.CharField(_('Nome'), max_length=255)
    type = models.CharField(_('Tipo'), max_length=50, null=True, blank=True)
    description = models.TextField(_('Descrição'), null=True, blank=True)
    provider = models.ForeignKey('providers.Provider', null=True, blank=True)
    charge = models.ForeignKey('Charge', null=True, blank=True)

    def __str__(self):
        return self.name

覆盖范围

class Coverage(models.Model):
    code = models.CharField(_('Código'), max_length=20, null=True, blank=True)
    vehicle_code = models.CharField(_('Código do veículo (ACRISS)'), max_length=4, null=True, blank=True)
    charge = models.ForeignKey('Charge', null=True, blank=True)

车辆

class Vehicle(models.Model):

    code = models.CharField(_('Código'), max_length=100)
    description = models.CharField(_('Descrição'), max_length=255, null=True, blank=True)
    model = models.CharField(_('Modelo'), max_length=100, null=True, blank=True)
    brand = models.CharField(_('Fabricante'), max_length=100, null=True, blank=True)
    group = models.ForeignKey('Group', null=True, blank=True)
    optionals = models.ManyToManyField('Optional', related_name='vehicle_optional')
    coverages = models.ManyToManyField('Coverage', related_name='vehicle_coverage')

    def __str__(self):
        return self.code

我正在尝试使用 factory_boy 从该模型创建灯具.

class CoverageFactory(factory.Factory):
    class Meta:
        model = Coverage
    charge = factory.SubFactory(ChargeFactory)

class OptionalFactory(factory.Factory):
    class Meta:
        model = Optional
    provider = factory.SubFactory(ProviderFactory)
    charge = factory.SubFactory(ChargeFactory)

class VehicleFactory(factory.Factory):
    class Meta:
        model = Vehicle
    group = factory.SubFactory(GroupFactory)
    optionals = factory.SubFactory(OptionalFactory)
    coverages = factory.SubFactory(CoverageFactory)

在我的测试中，它是这样实例化的:

optional = OptionalFactory(
    name="GPS",
    type="13",
    description="",
    charge=charge,
    provider=provider
)

coverage = CoverageFactory(
    code="ALI",
    vehicle_code="ABCD",
    charge=charge
)

vehicle = VehicleFactory(
    code="ECMM",
    description="GRUPO AX - MOVIDA ON",
    model="MOBI LIKE, OU SIMILAR",
    brand="",
    optionals=optional,
    coverages=coverage
)

当我运行测试时，使用 pytest-django ，我收到此错误。

ValueError: "<Vehicle: ECMM>" needs to have a value for field "id" before this many-to-many relationship can be used.

我已阅读有关Simple Many-to-many relationship的factory_boy文档和 Many-to-many relation with a ‘through’但无法修复。

Answer 1

When calling UserFactory() or UserFactory.build(), no group binding will be created.

But when UserFactory.create(groups=(group1, group2, group3)) is called, the groups declaration will add passed in groups to the set of groups for the user.

id 字段将在您

时生成

optional = OptionalFactory.create(  # note the .create()
    name="GPS",
    type="13",
    description="",
    charge=charge,
    provider=provider
)

然后当你

vehicle = VehicleFactory.create(
    ...
    optionals=(optional,),
)

可以建立多对多可选。还请注意，可选参数是(可选，)。该函数需要一个可迭代的