|
| 1 | +from sqlalchemy.ext.asyncio import AsyncSession |
| 2 | +from sqlalchemy.exc import SQLAlchemyError |
| 3 | +from sqlalchemy import Select |
| 4 | +from sqlalchemy.orm import joinedload, selectinload |
| 5 | +from typing import ClassVar, Sequence |
| 6 | + |
| 7 | +from config import BaseModel |
| 8 | + |
| 9 | + |
| 10 | +class BaseDAO: |
| 11 | + """ |
| 12 | + Базовый DAO класс для CRUD модели |
| 13 | +
|
| 14 | + Универсальный класс для легкого опеределения |
| 15 | +
|
| 16 | + CRUD модели |
| 17 | +
|
| 18 | + Примеры:: |
| 19 | +
|
| 20 | + # Поиск сущности |
| 21 | + item = ModelDAO.find_item_by_args( |
| 22 | + session=session, |
| 23 | + id=3, |
| 24 | + ) |
| 25 | + # Множественный поиск сущностей |
| 26 | + items = ModelDAO.find_all_items_by_args( |
| 27 | + session = session, |
| 28 | + one_to_many = (Model.tag,), |
| 29 | + name='model', |
| 30 | + ) |
| 31 | + # Создание сущности |
| 32 | + item = ModelDAO.add( |
| 33 | + session, |
| 34 | + id=3, |
| 35 | + name='model', |
| 36 | + ) |
| 37 | + """ |
| 38 | + model: ClassVar[BaseModel | None] = None |
| 39 | + |
| 40 | + @classmethod |
| 41 | + async def find_item_by_args(cls, |
| 42 | + session: AsyncSession, |
| 43 | + one_to_many: Sequence[BaseModel] | None = None, |
| 44 | + many_to_many: Sequence[BaseModel] | None = None, |
| 45 | + **kwargs: dict[str, str | int], |
| 46 | + ) -> BaseModel: |
| 47 | + """ |
| 48 | + Нахождение и возращение сущности |
| 49 | +
|
| 50 | + Args: |
| 51 | + session (AsyncSession): Текущая сессия |
| 52 | +
|
| 53 | + one_to_many (Sequence[BaseModel] | None, optional): Выбранные поля |
| 54 | + для one_to_many |
| 55 | + которые имеют отношение например: (Product.user) |
| 56 | +
|
| 57 | + many_to_many (Sequence[BaseModel] | None, optional): Выбранные поля |
| 58 | + для many_to_many |
| 59 | + которые имеют отношение например: (Product.categories) |
| 60 | +
|
| 61 | + Returns: |
| 62 | + BaseModel: Сущность из выборки |
| 63 | + """ |
| 64 | + stmt = struct_options_statment( |
| 65 | + model=cls.model, |
| 66 | + one_to_many=one_to_many, |
| 67 | + many_to_many=many_to_many, |
| 68 | + **kwargs, |
| 69 | + ) |
| 70 | + result = await session.scalar(statement=stmt) |
| 71 | + return result |
| 72 | + |
| 73 | + @classmethod |
| 74 | + async def find_all_items_by_args(cls, |
| 75 | + session: AsyncSession, |
| 76 | + one_to_many: Sequence[BaseModel] | None = None, |
| 77 | + many_to_many: Sequence[BaseModel] | None = None, |
| 78 | + **kwargs: dict[str, str | int], |
| 79 | + ) -> list[BaseModel]: |
| 80 | + """ |
| 81 | + Нахождение и возращение множества сущностей |
| 82 | +
|
| 83 | + Args: |
| 84 | + session (AsyncSession): Текущая сессия |
| 85 | +
|
| 86 | + one_to_many (Sequence[BaseModel] | None, optional): Выбранные поля |
| 87 | + для one_to_many |
| 88 | + которые имеют отношение например: (Product.user) |
| 89 | +
|
| 90 | + many_to_many (Sequence[BaseModel] | None, optional): Выбранные поля |
| 91 | + для many_to_many |
| 92 | + которые имеют отношение например: (Product.categories) |
| 93 | +
|
| 94 | + Returns: |
| 95 | + BaseModel: Сущности из выборки |
| 96 | + """ |
| 97 | + stmt = struct_options_statment( |
| 98 | + model=cls.model, |
| 99 | + one_to_many=one_to_many, |
| 100 | + many_to_many=many_to_many, |
| 101 | + **kwargs, |
| 102 | + ) |
| 103 | + result = await session.scalars(statement=stmt) |
| 104 | + return list(result) |
| 105 | + |
| 106 | + @classmethod |
| 107 | + async def add(cls, |
| 108 | + session: AsyncSession, |
| 109 | + **values, |
| 110 | + ) -> BaseModel: |
| 111 | + async with session.begin(): |
| 112 | + instance = cls.model(**values) |
| 113 | + session.add(instance=instance) |
| 114 | + try: |
| 115 | + await session.commit() |
| 116 | + except SQLAlchemyError as ex: |
| 117 | + await session.rollback() |
| 118 | + raise ex |
| 119 | + return instance |
| 120 | + |
| 121 | + |
| 122 | +def struct_options_statment(model: BaseModel, |
| 123 | + one_to_many: Sequence[BaseModel] | None = None, |
| 124 | + many_to_many: Sequence[BaseModel] | None = None, |
| 125 | + **kwargs: dict[str, str | int], |
| 126 | + ) -> Select: |
| 127 | + """ |
| 128 | + Струкрутирование запроса SELECT для выборки |
| 129 | +
|
| 130 | + Args: |
| 131 | + model (BaseModel): Модель таблицы для выборки |
| 132 | + one_to_many (Sequence[BaseModel] | None, optional): Выбранные поля |
| 133 | + для one_to_many |
| 134 | + которые имеют отношение например: (Product.user) |
| 135 | +
|
| 136 | + many_to_many (Sequence[BaseModel] | None, optional): Выбранные поля |
| 137 | + для many_to_many |
| 138 | + которые имеют отношение например: (Product.categories) |
| 139 | +
|
| 140 | + Returns: |
| 141 | + Select: Экземпляр запроса |
| 142 | + """ |
| 143 | + if one_to_many and many_to_many: |
| 144 | + stmt = (Select(model) |
| 145 | + .filter_by(**kwargs) |
| 146 | + .options(joinedload(*one_to_many)) |
| 147 | + .options(selectinload(*many_to_many))) |
| 148 | + elif one_to_many: |
| 149 | + stmt = (Select(model) |
| 150 | + .filter_by(**kwargs) |
| 151 | + .options(joinedload(*one_to_many))) |
| 152 | + elif many_to_many: |
| 153 | + stmt = (Select(model) |
| 154 | + .filter_by(**kwargs) |
| 155 | + .options(selectinload(*many_to_many))) |
| 156 | + else: |
| 157 | + stmt = (Select(model) |
| 158 | + .filter_by(**kwargs)) |
| 159 | + return stmt |
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