添加异步数据库支持,更新相关模型和会话管理

This commit is contained in:
jxxghp
2025-07-30 13:18:45 +08:00
parent 6d1de8a2e4
commit f14f4e1e9b
8 changed files with 286 additions and 382 deletions
+7 -6
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@@ -1,6 +1,7 @@
from typing import List, Any, Dict, Optional from typing import List, Any, Dict, Optional
from fastapi import APIRouter, Depends, HTTPException from fastapi import APIRouter, Depends, HTTPException
from sqlalchemy.ext.asyncio import AsyncSession
from sqlalchemy.orm import Session from sqlalchemy.orm import Session
from starlette.background import BackgroundTasks from starlette.background import BackgroundTasks
@@ -12,7 +13,7 @@ from app.command import Command
from app.core.event import EventManager from app.core.event import EventManager
from app.core.plugin import PluginManager from app.core.plugin import PluginManager
from app.core.security import verify_token from app.core.security import verify_token
from app.db import get_db from app.db import get_db, get_async_db
from app.db.models import User from app.db.models import User
from app.db.models.site import Site from app.db.models.site import Site
from app.db.models.siteicon import SiteIcon from app.db.models.siteicon import SiteIcon
@@ -242,19 +243,19 @@ def test_site(site_id: int,
@router.get("/icon/{site_id}", summary="站点图标", response_model=schemas.Response) @router.get("/icon/{site_id}", summary="站点图标", response_model=schemas.Response)
def site_icon(site_id: int, async def site_icon(site_id: int,
db: Session = Depends(get_db), db: AsyncSession = Depends(get_async_db),
_: schemas.TokenPayload = Depends(verify_token)) -> Any: _: schemas.TokenPayload = Depends(verify_token)) -> Any:
""" """
获取站点图标:base64或者url 获取站点图标:base64或者url
""" """
site = Site.get(db, site_id) site = await Site.async_get(db, site_id)
if not site: if not site:
raise HTTPException( raise HTTPException(
status_code=404, status_code=404,
detail=f"站点 {site_id} 不存在", detail=f"站点 {site_id} 不存在",
) )
icon = SiteIcon.get_by_domain(db, site.domain) icon = await SiteIcon.async_get_by_domain(db, site.domain)
if not icon: if not icon:
return schemas.Response(success=False, message="站点图标不存在!") return schemas.Response(success=False, message="站点图标不存在!")
return schemas.Response(success=True, data={ return schemas.Response(success=True, data={
+265 -60
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@@ -1,45 +1,106 @@
from typing import Any, Generator, List, Optional, Self, Tuple import asyncio
from typing import Any, Generator, List, Optional, Self, Tuple, AsyncGenerator, Sequence
from sqlalchemy import NullPool, QueuePool, and_, create_engine, inspect, text from sqlalchemy import NullPool, QueuePool, and_, create_engine, inspect, text
from sqlalchemy.ext.asyncio import create_async_engine, AsyncSession, async_sessionmaker
from sqlalchemy.orm import Session, as_declarative, declared_attr, scoped_session, sessionmaker from sqlalchemy.orm import Session, as_declarative, declared_attr, scoped_session, sessionmaker
from app.core.config import settings from app.core.config import settings
# 根据池类型设置 poolclass 和相关参数
pool_class = NullPool if settings.DB_POOL_TYPE == "NullPool" else QueuePool
connect_args = {
"timeout": settings.DB_TIMEOUT
}
# 启用 WAL 模式时的额外配置
if settings.DB_WAL_ENABLE:
connect_args["check_same_thread"] = False
db_kwargs = {
"url": f"sqlite:///{settings.CONFIG_PATH}/user.db",
"pool_pre_ping": settings.DB_POOL_PRE_PING,
"echo": settings.DB_ECHO,
"poolclass": pool_class,
"pool_recycle": settings.DB_POOL_RECYCLE,
"connect_args": connect_args
}
# 当使用 QueuePool 时,添加 QueuePool 特有的参数
if pool_class == QueuePool:
db_kwargs.update({
"pool_size": settings.CONF.dbpool,
"pool_timeout": settings.DB_POOL_TIMEOUT,
"max_overflow": settings.CONF.dbpooloverflow
})
# 创建数据库引擎
Engine = create_engine(**db_kwargs)
# 根据配置设置日志模式
journal_mode = "WAL" if settings.DB_WAL_ENABLE else "DELETE"
with Engine.connect() as connection:
current_mode = connection.execute(text(f"PRAGMA journal_mode={journal_mode};")).scalar()
print(f"Database journal mode set to: {current_mode}")
# 会话工厂 def _get_database_engine(is_async: bool = False):
"""
获取数据库连接参数并设置WAL模式
:param is_async: 是否创建异步引擎,True - 异步引擎, False - 同步引擎
:return: 返回对应的数据库引擎
"""
# 连接参数
_connect_args = {
"timeout": settings.DB_TIMEOUT,
}
# 启用 WAL 模式时的额外配置
if settings.DB_WAL_ENABLE:
_connect_args["check_same_thread"] = False
# 创建同步引擎
if not is_async:
# 根据池类型设置 poolclass 和相关参数
_pool_class = NullPool if settings.DB_POOL_TYPE == "NullPool" else QueuePool
# 数据库参数
_db_kwargs = {
"url": f"sqlite:///{settings.CONFIG_PATH}/user.db",
"pool_pre_ping": settings.DB_POOL_PRE_PING,
"echo": settings.DB_ECHO,
"poolclass": _pool_class,
"pool_recycle": settings.DB_POOL_RECYCLE,
"connect_args": _connect_args
}
# 当使用 QueuePool 时,添加 QueuePool 特有的参数
if _pool_class == QueuePool:
_db_kwargs.update({
"pool_size": settings.CONF.dbpool,
"pool_timeout": settings.DB_POOL_TIMEOUT,
"max_overflow": settings.CONF.dbpooloverflow
})
# 创建数据库引擎
engine = create_engine(**_db_kwargs)
# 设置WAL模式
_journal_mode = "WAL" if settings.DB_WAL_ENABLE else "DELETE"
with engine.connect() as connection:
current_mode = connection.execute(text(f"PRAGMA journal_mode={_journal_mode};")).scalar()
print(f"Database journal mode set to: {current_mode}")
return engine
else:
# 数据库参数,只能使用 NullPool
_db_kwargs = {
"url": f"sqlite+aiosqlite:///{settings.CONFIG_PATH}/user.db",
"pool_pre_ping": settings.DB_POOL_PRE_PING,
"echo": settings.DB_ECHO,
"poolclass": NullPool,
"pool_recycle": settings.DB_POOL_RECYCLE,
"connect_args": _connect_args
}
# 创建异步数据库引擎
async_engine = create_async_engine(**_db_kwargs)
# 设置WAL模式
_journal_mode = "WAL" if settings.DB_WAL_ENABLE else "DELETE"
async def set_async_wal_mode():
"""
设置异步引擎的WAL模式
"""
async with async_engine.connect() as _connection:
result = await _connection.execute(text(f"PRAGMA journal_mode={_journal_mode};"))
_current_mode = result.scalar()
print(f"Async database journal mode set to: {_current_mode}")
try:
asyncio.run(set_async_wal_mode())
except Exception as e:
print(f"Failed to set async WAL mode: {e}")
return async_engine
# 同步数据库引擎
Engine = _get_database_engine(is_async=False)
# 异步数据库引擎
AsyncEngine = _get_database_engine(is_async=True)
# 同步会话工厂
SessionFactory = sessionmaker(bind=Engine) SessionFactory = sessionmaker(bind=Engine)
# 多线程全局使用的数据库会话 # 异步会话工厂
AsyncSessionFactory = async_sessionmaker(bind=AsyncEngine, class_=AsyncSession)
# 同步多线程全局使用的数据库会话
ScopedSession = scoped_session(SessionFactory) ScopedSession = scoped_session(SessionFactory)
@@ -57,37 +118,32 @@ def get_db() -> Generator:
db.close() db.close()
def perform_checkpoint(mode: str = "PASSIVE"): async def get_async_db() -> AsyncGenerator[AsyncSession, None]:
""" """
执行 SQLite 的 checkpoint 操作,将 WAL 文件内容写回主数据库 获取异步数据库会话,用于WEB请求
:param mode: checkpoint 模式,可选值包括 "PASSIVE""FULL""RESTART""TRUNCATE" :return: AsyncSession
默认为 "PASSIVE",即不锁定 WAL 文件的轻量级同步
""" """
if not settings.DB_WAL_ENABLE: async with AsyncSessionFactory() as session:
return try:
valid_modes = {"PASSIVE", "FULL", "RESTART", "TRUNCATE"} yield session
if mode.upper() not in valid_modes: finally:
raise ValueError(f"Invalid checkpoint mode '{mode}'. Must be one of {valid_modes}") await session.close()
try:
# 使用指定的 checkpoint 模式,确保 WAL 文件数据被正确写回主数据库
with Engine.connect() as conn:
conn.execute(text(f"PRAGMA wal_checkpoint({mode.upper()});"))
except Exception as e:
print(f"Error during WAL checkpoint: {e}")
def close_database(): async def close_database():
""" """
关闭所有数据库连接并清理资源 关闭所有数据库连接并清理资源
""" """
try: try:
# 释放连接池SQLite 会自动清空 WAL 文件,这里不单独再调用 checkpoint # 释放同步连接池
Engine.dispose() Engine.dispose() # noqa
except Exception as e: # 释放异步连接池
print(f"Error while disposing database connections: {e}") await AsyncEngine.dispose()
except Exception as err:
print(f"Error while disposing database connections: {err}")
def get_args_db(args: tuple, kwargs: dict) -> Optional[Session]: def _get_args_db(args: tuple, kwargs: dict) -> Optional[Session]:
""" """
从参数中获取数据库Session对象 从参数中获取数据库Session对象
""" """
@@ -105,7 +161,25 @@ def get_args_db(args: tuple, kwargs: dict) -> Optional[Session]:
return db return db
def update_args_db(args: tuple, kwargs: dict, db: Session) -> Tuple[tuple, dict]: def _get_args_async_db(args: tuple, kwargs: dict) -> Optional[AsyncSession]:
"""
从参数中获取异步数据库AsyncSession对象
"""
db = None
if args:
for arg in args:
if isinstance(arg, AsyncSession):
db = arg
break
if kwargs:
for key, value in kwargs.items():
if isinstance(value, AsyncSession):
db = value
break
return db
def _update_args_db(args: tuple, kwargs: dict, db: Session) -> Tuple[tuple, dict]:
""" """
更新参数中的数据库Session对象,关键字传参时更新db的值,否则更新第1或第2个参数 更新参数中的数据库Session对象,关键字传参时更新db的值,否则更新第1或第2个参数
""" """
@@ -119,6 +193,20 @@ def update_args_db(args: tuple, kwargs: dict, db: Session) -> Tuple[tuple, dict]
return args, kwargs return args, kwargs
def _update_args_async_db(args: tuple, kwargs: dict, db: AsyncSession) -> Tuple[tuple, dict]:
"""
更新参数中的异步数据库AsyncSession对象,关键字传参时更新db的值,否则更新第1或第2个参数
"""
if kwargs and 'db' in kwargs:
kwargs['db'] = db
elif args:
if args[0] is None:
args = (db, *args[1:])
else:
args = (args[0], db, *args[2:])
return args, kwargs
def db_update(func): def db_update(func):
""" """
数据库更新类操作装饰器,第一个参数必须是数据库会话或存在db参数 数据库更新类操作装饰器,第一个参数必须是数据库会话或存在db参数
@@ -128,14 +216,14 @@ def db_update(func):
# 是否关闭数据库会话 # 是否关闭数据库会话
_close_db = False _close_db = False
# 从参数中获取数据库会话 # 从参数中获取数据库会话
db = get_args_db(args, kwargs) db = _get_args_db(args, kwargs)
if not db: if not db:
# 如果没有获取到数据库会话,创建一个 # 如果没有获取到数据库会话,创建一个
db = ScopedSession() db = ScopedSession()
# 标记需要关闭数据库会话 # 标记需要关闭数据库会话
_close_db = True _close_db = True
# 更新参数中的数据库会话 # 更新参数中的数据库会话
args, kwargs = update_args_db(args, kwargs, db) args, kwargs = _update_args_db(args, kwargs, db)
try: try:
# 执行函数 # 执行函数
result = func(*args, **kwargs) result = func(*args, **kwargs)
@@ -154,6 +242,41 @@ def db_update(func):
return wrapper return wrapper
def async_db_update(func):
"""
异步数据库更新类操作装饰器,第一个参数必须是异步数据库会话或存在db参数
"""
async def wrapper(*args, **kwargs):
# 是否关闭数据库会话
_close_db = False
# 从参数中获取异步数据库会话
db = _get_args_async_db(args, kwargs)
if not db:
# 如果没有获取到异步数据库会话,创建一个
db = AsyncSessionFactory()
# 标记需要关闭数据库会话
_close_db = True
# 更新参数中的异步数据库会话
args, kwargs = _update_args_async_db(args, kwargs, db)
try:
# 执行函数
result = await func(*args, **kwargs)
# 提交事务
await db.commit()
except Exception as err:
# 回滚事务
await db.rollback()
raise err
finally:
# 关闭数据库会话
if _close_db:
await db.close()
return result
return wrapper
def db_query(func): def db_query(func):
""" """
数据库查询操作装饰器,第一个参数必须是数据库会话或存在db参数 数据库查询操作装饰器,第一个参数必须是数据库会话或存在db参数
@@ -164,14 +287,14 @@ def db_query(func):
# 是否关闭数据库会话 # 是否关闭数据库会话
_close_db = False _close_db = False
# 从参数中获取数据库会话 # 从参数中获取数据库会话
db = get_args_db(args, kwargs) db = _get_args_db(args, kwargs)
if not db: if not db:
# 如果没有获取到数据库会话,创建一个 # 如果没有获取到数据库会话,创建一个
db = ScopedSession() db = ScopedSession()
# 标记需要关闭数据库会话 # 标记需要关闭数据库会话
_close_db = True _close_db = True
# 更新参数中的数据库会话 # 更新参数中的数据库会话
args, kwargs = update_args_db(args, kwargs, db) args, kwargs = _update_args_db(args, kwargs, db)
try: try:
# 执行函数 # 执行函数
result = func(*args, **kwargs) result = func(*args, **kwargs)
@@ -186,6 +309,38 @@ def db_query(func):
return wrapper return wrapper
def async_db_query(func):
"""
异步数据库查询操作装饰器,第一个参数必须是异步数据库会话或存在db参数
注意:db.query列表数据时,需要转换为list返回
"""
async def wrapper(*args, **kwargs):
# 是否关闭数据库会话
_close_db = False
# 从参数中获取异步数据库会话
db = _get_args_async_db(args, kwargs)
if not db:
# 如果没有获取到异步数据库会话,创建一个
db = AsyncSessionFactory()
# 标记需要关闭数据库会话
_close_db = True
# 更新参数中的异步数据库会话
args, kwargs = _update_args_async_db(args, kwargs, db)
try:
# 执行函数
result = await func(*args, **kwargs)
except Exception as err:
raise err
finally:
# 关闭数据库会话
if _close_db:
await db.close()
return result
return wrapper
@as_declarative() @as_declarative()
class Base: class Base:
id: Any id: Any
@@ -195,11 +350,22 @@ class Base:
def create(self, db: Session): def create(self, db: Session):
db.add(self) db.add(self)
@async_db_update
async def async_create(self, db: AsyncSession):
db.add(self)
@classmethod @classmethod
@db_query @db_query
def get(cls, db: Session, rid: int) -> Self: def get(cls, db: Session, rid: int) -> Self:
return db.query(cls).filter(and_(cls.id == rid)).first() return db.query(cls).filter(and_(cls.id == rid)).first()
@classmethod
@async_db_query
async def async_get(cls, db: AsyncSession, rid: int) -> Self:
from sqlalchemy import select
result = await db.execute(select(cls).where(and_(cls.id == rid)))
return result.scalars().first()
@db_update @db_update
def update(self, db: Session, payload: dict): def update(self, db: Session, payload: dict):
payload = {k: v for k, v in payload.items() if v is not None} payload = {k: v for k, v in payload.items() if v is not None}
@@ -208,23 +374,53 @@ class Base:
if inspect(self).detached: if inspect(self).detached:
db.add(self) db.add(self)
@async_db_update
async def async_update(self, db: AsyncSession, payload: dict):
payload = {k: v for k, v in payload.items() if v is not None}
for key, value in payload.items():
setattr(self, key, value)
if inspect(self).detached:
db.add(self)
@classmethod @classmethod
@db_update @db_update
def delete(cls, db: Session, rid): def delete(cls, db: Session, rid):
db.query(cls).filter(and_(cls.id == rid)).delete() db.query(cls).filter(and_(cls.id == rid)).delete()
@classmethod
@async_db_update
async def async_delete(cls, db: AsyncSession, rid):
from sqlalchemy import select
result = await db.execute(select(cls).where(and_(cls.id == rid)))
user = result.scalars().first()
if user:
await db.delete(user)
@classmethod @classmethod
@db_update @db_update
def truncate(cls, db: Session): def truncate(cls, db: Session):
db.query(cls).delete() db.query(cls).delete()
@classmethod
@async_db_update
async def async_truncate(cls, db: AsyncSession):
from sqlalchemy import delete
await db.execute(delete(cls))
@classmethod @classmethod
@db_query @db_query
def list(cls, db: Session) -> List[Self]: def list(cls, db: Session) -> List[Self]:
return db.query(cls).all() return db.query(cls).all()
@classmethod
@async_db_query
async def async_list(cls, db: AsyncSession) -> Sequence[Self]:
from sqlalchemy import select
result = await db.execute(select(cls))
return result.scalars().all()
def to_dict(self): def to_dict(self):
return {c.name: getattr(self, c.name, None) for c in self.__table__.columns} # noqa return {c.name: getattr(self, c.name, None) for c in self.__table__.columns} # noqa
@declared_attr @declared_attr
def __tablename__(self) -> str: def __tablename__(self) -> str:
@@ -238,3 +434,12 @@ class DbOper:
def __init__(self, db: Session = None): def __init__(self, db: Session = None):
self._db = db self._db = db
class AsyncDbOper:
"""
异步数据库操作基类
"""
def __init__(self, db: AsyncSession = None):
self._db = db
-136
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@@ -1,136 +0,0 @@
import asyncio
from concurrent.futures import ThreadPoolExecutor
from functools import wraps, partial
from typing import Any, Callable, Coroutine, TypeVar
from sqlalchemy.orm import Session
from app.db import ScopedSession
T = TypeVar('T')
# 全局线程池,用于执行同步数据库操作
_db_executor = ThreadPoolExecutor(max_workers=10, thread_name_prefix="db_async")
def async_db_operation(func: Callable[..., T]) -> Callable[..., Coroutine[Any, Any, T]]:
"""
将同步数据库操作转换为异步操作的装饰器
"""
@wraps(func)
async def wrapper(*args, **kwargs) -> T:
# 在线程池中执行同步数据库操作
loop = asyncio.get_event_loop()
partial_func = partial(func, *args, **kwargs)
return await loop.run_in_executor(_db_executor, partial_func, ())
return wrapper
def async_db_session(func: Callable[..., T]) -> Callable[..., Coroutine[Any, Any, T]]:
"""
为异步操作提供数据库会话的装饰器
"""
@wraps(func)
async def wrapper(*args, **kwargs) -> T:
# 创建数据库会话
db = ScopedSession()
try:
# 将数据库会话添加到参数中
if 'db' not in kwargs:
kwargs['db'] = db
# 在线程池中执行同步数据库操作
loop = asyncio.get_event_loop()
partial_func = partial(func, *args, **kwargs)
return await loop.run_in_executor(_db_executor, partial_func, ())
finally:
db.close()
return wrapper
class AsyncDbOper:
"""
异步数据库操作基类
"""
def __init__(self, db: Session = None):
self._db = db
async def _get_db(self) -> Session:
"""
获取数据库会话
"""
if self._db:
return self._db
return ScopedSession()
@staticmethod
async def _execute_sync(func: Callable[..., T], *args, **kwargs) -> T:
"""
在线程池中执行同步数据库操作
"""
loop = asyncio.get_event_loop()
partial_func = partial(func, *args, **kwargs)
return await loop.run_in_executor(_db_executor, partial_func, ())
def to_async_db_oper(sync_oper_class):
"""
将同步数据库操作类转换为异步版本的装饰器
"""
class AsyncOperClass(AsyncDbOper):
def __init__(self, db: Session = None):
super().__init__(db)
self._sync_oper = sync_oper_class(db)
def __getattr__(self, name):
"""动态获取同步操作类的方法并转换为异步"""
if hasattr(self._sync_oper, name):
method = getattr(self._sync_oper, name)
if callable(method):
return async_db_operation(method)
raise AttributeError(f"'{self.__class__.__name__}' object has no attribute '{name}'")
return AsyncOperClass
# 异步数据库会话获取函数
async def get_async_db():
"""
异步获取数据库会话
"""
def _get_db():
return ScopedSession()
loop = asyncio.get_event_loop()
return await loop.run_in_executor(_db_executor, _get_db) # type: ignore
# 异步上下文管理器
class AsyncDbSession:
"""
异步数据库会话上下文管理器
"""
def __init__(self):
self.db = None
async def __aenter__(self):
self.db = await get_async_db()
return self.db
async def __aexit__(self, exc_type, exc_val, exc_tb):
if self.db:
self.db.close()
def shutdown_db_executor():
"""关闭数据库线程池"""
global _db_executor
if _db_executor:
_db_executor.shutdown(wait=True)
+9 -2
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@@ -1,7 +1,8 @@
from sqlalchemy import Column, Integer, String, Sequence from sqlalchemy import Column, Integer, String, Sequence, select
from sqlalchemy.ext.asyncio import AsyncSession
from sqlalchemy.orm import Session from sqlalchemy.orm import Session
from app.db import db_query, Base from app.db import db_query, Base, async_db_query
class SiteIcon(Base): class SiteIcon(Base):
@@ -22,3 +23,9 @@ class SiteIcon(Base):
@db_query @db_query
def get_by_domain(db: Session, domain: str): def get_by_domain(db: Session, domain: str):
return db.query(SiteIcon).filter(SiteIcon.domain == domain).first() return db.query(SiteIcon).filter(SiteIcon.domain == domain).first()
@classmethod
@async_db_query
async def async_get_by_domain(cls, db: AsyncSession, domain: str):
result = await db.execute(select(cls).where(cls.domain == domain))
return result.scalar_one_or_none()
+1 -4
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@@ -4,7 +4,6 @@ from contextlib import asynccontextmanager
from fastapi import FastAPI from fastapi import FastAPI
from app.chain.system import SystemChain from app.chain.system import SystemChain
from app.db.async_adapter import shutdown_db_executor
from app.helper.system import SystemHelper from app.helper.system import SystemHelper
from app.startup.command_initializer import init_command, stop_command, restart_command from app.startup.command_initializer import init_command, stop_command, restart_command
from app.startup.modules_initializer import init_modules, stop_modules from app.startup.modules_initializer import init_modules, stop_modules
@@ -80,6 +79,4 @@ async def lifespan(app: FastAPI):
# 停止插件 # 停止插件
stop_plugins() stop_plugins()
# 停止模块 # 停止模块
stop_modules() await stop_modules()
# 关闭数据库异步执行器
shutdown_db_executor()
+3 -3
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@@ -1,11 +1,11 @@
import sys import sys
from app.command import CommandChain
from app.core.cache import close_cache from app.core.cache import close_cache
from app.core.config import settings from app.core.config import settings
from app.core.module import ModuleManager from app.core.module import ModuleManager
from app.log import logger from app.log import logger
from app.utils.system import SystemUtils from app.utils.system import SystemUtils
from app.command import CommandChain
# SitesHelper涉及资源包拉取,提前引入并容错提示 # SitesHelper涉及资源包拉取,提前引入并容错提示
try: try:
@@ -105,7 +105,7 @@ def check_auth():
) )
def stop_modules(): async def stop_modules():
""" """
服务关闭 服务关闭
""" """
@@ -120,7 +120,7 @@ def stop_modules():
# 停止缓存连接 # 停止缓存连接
close_cache() close_cache()
# 停止数据库连接 # 停止数据库连接
close_database() await close_database()
# 停止前端服务 # 停止前端服务
stop_frontend() stop_frontend()
# 清理临时文件 # 清理临时文件
-171
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@@ -1,171 +0,0 @@
# 异步数据库操作指南
## 概述
本指南介绍如何在MoviePilot项目中实现异步数据库操作,而无需重写现有的同步数据库模块。
## 方案优势
1. **最小化改动**: 不需要重写现有的同步数据库操作代码
2. **渐进式迁移**: 可以逐步将需要异步的操作迁移到异步版本
3. **向后兼容**: 现有的同步代码继续正常工作
4. **性能提升**: 通过线程池执行同步数据库操作,避免阻塞事件循环
## 核心组件
### 1. 异步适配器 (`app/db/async_adapter.py`)
提供以下功能:
- `async_db_operation`: 将同步函数包装为异步函数
- `async_db_session`: 为异步操作提供数据库会话
- `AsyncDbOper`: 异步数据库操作基类
- `to_async_db_oper`: 将同步操作类转换为异步版本
- `AsyncDbSession`: 异步数据库会话上下文管理器
### 2. 异步操作类 (`app/db/async_user_oper.py`)
展示如何创建异步版本的数据库操作类。
## 使用方法
### 方法1: 使用装饰器自动转换
```python
from app.db.user_oper import UserOper
from app.db.async_adapter import to_async_db_oper
# 自动将同步类转换为异步版本
AsyncUserOper = to_async_db_oper(UserOper)
# 使用异步版本
async def example():
async_user_oper = AsyncUserOper()
users = await async_user_oper.list()
return users
```
### 方法2: 手动创建异步方法
```python
from app.db.async_adapter import async_db_operation
class AsyncUserOperManual:
def __init__(self, db: Session = None):
self._sync_oper = UserOper(db)
@async_db_operation
def list(self) -> List[User]:
return self._sync_oper.list()
@async_db_operation
def add(self, **kwargs):
return self._sync_oper.add(**kwargs)
```
### 方法3: 使用异步上下文管理器
```python
from app.db.async_adapter import AsyncDbSession
async def example():
async with AsyncDbSession() as db:
# 直接使用同步操作,但在线程池中执行
from functools import partial
users = await asyncio.get_event_loop().run_in_executor(
None, partial(lambda db: db.query(User).all(), db)
)
return users
```
### 方法4: 装饰器包装单个函数
```python
from app.db.async_adapter import async_db_operation
@async_db_operation
def get_user_by_name_sync(db: Session, name: str) -> User:
return db.query(User).filter(User.name == name).first()
async def example():
async with AsyncDbSession() as db:
user = await get_user_by_name_sync(db, "admin")
return user
```
## 在FastAPI中使用
### 依赖注入
```python
async def get_current_user_async_dependency(
token_data: schemas.TokenPayload = Depends(verify_token)
) -> User:
async with AsyncDbSession() as db:
from functools import partial
user = await asyncio.get_event_loop().run_in_executor(
None, partial(User.get, db, rid=token_data.sub)
)
if not user:
raise HTTPException(status_code=403, detail="用户不存在")
return user
@router.get("/me/async")
async def get_current_user_async(
current_user: User = Depends(get_current_user_async_dependency)
):
return current_user
```
### API端点
```python
@router.get("/users/async")
async def get_users_async():
async_user_oper = AsyncUserOper()
users = await async_user_oper.list()
return users
```
## 并发操作
### 批量操作
```python
@router.post("/users/batch-async")
async def create_users_batch_async(users_data: List[schemas.UserCreate]):
async_user_oper = AsyncUserOper()
# 并发创建用户
tasks = []
for user_data in users_data:
task = async_user_oper.add(**user_data.dict())
tasks.append(task)
# 等待所有任务完成
await asyncio.gather(*tasks)
# 获取创建的用户列表
all_users = await async_user_oper.list()
return all_users[-len(users_data):]
```
### 复杂查询
```python
@router.get("/users/stats/async")
async def get_user_stats_async():
async_user_oper = AsyncUserOper()
# 并发执行多个数据库查询
users_task = async_user_oper.list()
active_users_task = async_user_oper.get_active_users()
# 等待所有查询完成
users, active_users = await asyncio.gather(users_task, active_users_task)
return {
"total_users": len(users),
"active_users": len(active_users),
"inactive_users": len(users) - len(active_users)
}
```
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@@ -60,6 +60,7 @@ Pinyin2Hanzi~=0.1.1
pywebpush~=2.0.3 pywebpush~=2.0.3
python-cookietools==0.0.4 python-cookietools==0.0.4
aiofiles~=24.1.0 aiofiles~=24.1.0
aiosqlite~=0.21.0
jieba~=0.42.1 jieba~=0.42.1
rsa~=4.9 rsa~=4.9
redis~=6.2.0 redis~=6.2.0