我试图为两个相似的具体类提供一个唯一的接口,它们继承自一个公共抽象类
My django模型类:
class Metadata(models.Model):
name = models.CharField(max_length=255)
sequence = models.PositiveSmallIntegerField()
is_choices = False
class Meta:
abstract = True
class MetadataScalar(Metadata):
string_format = models.CharField(max_length=255, blank=True, null=True)
class MetadataChoices(Metadata):
is_choices = True
choices = models.CharField(max_length=255, blank=True, null=True)
我的graphene django api:
class MetadataNode(DjangoObjectType):
class Meta:
interfaces = (Node,)
connection_class = Connection
model = Metadata
fields = '__all__'
class MetadataScalarNode(MetadataNode):
class Meta:
interfaces = (Node,)
connection_class = Connection
model = MetadataScalar
fields = '__all__'
class MetadataChoicesNode(MetadataNode):
class Meta:
interfaces = (Node,)
connection_class = Connection
model = MetadataChoices
fields = '__all__'
class CreateMetadata(ClientIDMutation):
metadata = Field(MetadataNode)
class Input:
name = String(max_length=255, required=True)
sequence = Int(required=True)
string_format = String()
choices = List(String)
@classmethod
def mutate_and_get_payload(cls, root, info, **input):
if 'string_format' in input:
metadata = MetadataScalar.objects.create(
name=input.get('name'),
sequence=input.get('sequence'),
string_format=input.get('string_format')
)
elif 'choices' in input:
metadata = MetadataChoices.objects.create(
name=input.get('name'),
sequence=input.get('sequence'),
choices=','.join(input.get('choices'))
)
return CreateMetadata(metadata=metadata)
查询与CreateMetadata
对应的graphql变异时,元数据具体类被成功创建。;-)
问题是,当查询在结果中请求创建的具体Metadata
(此处为MetadataScalar
或MetadataChoices
)时,graphql无法找到具体类的节点,并输出以下错误消息:
Expected value of type "MetadataNode" but got: MetadataScalar.
请参考以下一个查询示例:
mutation {
createMetadata (input: {
stringFormat: "foo"
sequence: 12
name: "bar"
}) {
metadata {
name
sequence
}
}
}
如何使其工作良好,而不必在查询的第二部分中指定两种不同的结果类型(metadataScalar
和metadataChoices
变量)
试试看
使用你的界面。 Union不能有任何字段,因此如果使用Union vs接口,则需要有重复字段。 https://docs.graphene-python.org/en/latest/types/unions/
可以使用Union来指定多个不同的结果类
就你而言,那将是:
graphql查询将如下所示:
相关问题 更多 >
编程相关推荐