我正在制作一个示例 Fast Api 服务器,使用 Tortoise ORM 作为异步 orm 库,但我似乎无法返回我定义的关系。这些是我的关系:
# Category
from tortoise.fields.data import DatetimeField
from tortoise.models import Model
from tortoise.fields import UUIDField, CharField
from tortoise.fields.relational import ManyToManyField
from tortoise.contrib.pydantic import pydantic_model_creator
class Category(Model):
id = UUIDField(pk=True)
name = CharField(max_length=255)
description = CharField(max_length=255)
keywords = ManyToManyField(
"models.Keyword", related_name="categories", through="category_keywords"
)
created_on = DatetimeField(auto_now_add=True)
updated_on = DatetimeField(auto_now=True)
Category_dto = pydantic_model_creator(Category, name="Category", allow_cycles = True)
# Keyword
from models.expense import Expense
from models.category import Category
from tortoise.fields.data import DatetimeField
from tortoise.fields.relational import ManyToManyRelation
from tortoise.models import Model
from tortoise.fields import UUIDField, CharField
from tortoise.contrib.pydantic import pydantic_model_creator
class Keyword(Model):
id = UUIDField(pk=True)
name = CharField(max_length=255)
description = CharField(max_length=255)
categories: ManyToManyRelation[Category]
expenses: ManyToManyRelation[Expense]
created_on = DatetimeField(auto_now_add=True)
updated_on = DatetimeField(auto_now=True)
class Meta:
table="keyword"
Keyword_dto = pydantic_model_creator(Keyword)
表已正确创建。将关键字添加到类别时,数据库状态一切正常。问题是当我想查询类别并包含关键字时。我有这样的代码:
class CategoryRepository():
@staticmethod
async def get_one(id: str) -> Category:
category_orm = await Category.get_or_none(id=id).prefetch_related('keywords')
if (category_orm is None):
raise NotFoundHTTP('Category')
return category_orm
在这里调试category_orm我有以下内容:
运行时进行category_orm调试
哪种告诉我它们已加载。
然后当我无法使用 Pydantic 模型时我有这个代码
class CategoryUseCases():
@staticmethod
async def get_one(id: str) -> Category_dto:
category_orm = await CategoryRepository.get_one(id)
category = await Category_dto.from_tortoise_orm(category_orm)
return category
并调试这个,没有keywords
field
运行时类别(pydantic)调试
查看tortoise orm的源码了解该函数from_tortoise_orm
@classmethod
async def from_tortoise_orm(cls, obj: "Model") -> "PydanticModel":
"""
Returns a serializable pydantic model instance built from the provided model instance.
.. note::
This will prefetch all the relations automatically. It is probably what you want.
但我的关系就是没有归还。有人有类似的经历吗?