我正在使用棉花糖 3.4.0 和棉花糖 sqlcellchemy 0.22.2
我有这个SQLAlchemy模型和棉花糖模式
class Zone(Base):
zone_id = Column(Integer, primary_key=True)
name = Column(String(65))
location_id = Column(Integer, ForeignKey('locations.location_id'))
location = relationship("Location", lazy="joined")
class ZoneSchema(SQLAlchemySchema):
class Meta:
model = Zone
fields = ("zone_id", "name", "location")
ordered = True
load_instance = True
zone_id = auto_field(data_key="id")
location = fields.Nested(LocationSchema)
如果我删除zone_id = auto_field(data_key="id")
字段按要求排序。
如果我删除
fields = ("zone_id", "name", "location")
ordered = True
密钥根据请求设置为id。
如果我运行上面的代码,我会收到此错误
File "[...]/models_schema.py", line 30, in <module>
class ZoneSchema(SQLAlchemySchema):
File "/venvs/backend-api/lib/python3.8/site-packages/marshmallow/schema.py", line 107, in __new__
cls_fields = _get_fields(attrs, base.FieldABC, pop=True, ordered=ordered)
File "/venvs/backend-api/lib/python3.8/site-packages/marshmallow/schema.py", line 57, in _get_fields
fields.sort(key=lambda pair: pair[1]._creation_index)
File "/venvs/backend-api/lib/python3.8/site-packages/marshmallow/schema.py", line 57, in <lambda>
fields.sort(key=lambda pair: pair[1]._creation_index)
AttributeError: 'SQLAlchemyAutoField' object has no attribute '_creation_index'
有人可以向我解释如何设置访问zone_id字段并添加"data_key"属性吗?
作为最后的手段,我阅读了文档,并设法自己找到了答案。
class ZoneSchema(SQLAlchemySchema):
class Meta:
model = Zone
fields = ("zone_id", "name", "location")
ordered = True
load_instance = True
location = fields.Nested(LocationSchema)
@pre_dump
def set_data_key_for_zone_id(self, data, many, **kwargs):
self.fields.get("zone_id").data_key = "id"
return data
如您所见,我保留了ordered = True
部分,并使用预转储装饰器访问zone_id
字段并设置data_key
属性。
如果有更好的方法,请告诉我/我们!