"""MySQL 异步连接（SQLAlchemy 2.0 async）"""
from collections.abc import AsyncGenerator

from sqlalchemy.ext.asyncio import AsyncSession, async_sessionmaker, create_async_engine

from app.config import settings

engine = create_async_engine(
    settings.database_url,
    pool_size=20,
    max_overflow=10,
    pool_recycle=3600,
    pool_pre_ping=True,
    echo=False,
)

SessionFactory = async_sessionmaker(
    engine, class_=AsyncSession, expire_on_commit=False, autoflush=False
)


async def get_db() -> AsyncGenerator[AsyncSession, None]:
    async with SessionFactory() as session:
        yield session