from sqlalchemy.ext.asyncio import create_async_engine, AsyncSession, async_sessionmaker
from alien_gateway.config import settings

# 异步数据库引擎
engine = create_async_engine(
    settings.SQLALCHEMY_DATABASE_URI.replace("mysql+pymysql", "mysql+aiomysql"),
    echo=True,
    pool_pre_ping=True,
)

AsyncSessionLocal = async_sessionmaker(
    bind=engine,
    class_=AsyncSession,
    expire_on_commit=False,
)

async def get_db():
    """获取数据库 Session 的依赖项"""
    async with AsyncSessionLocal() as session:
        yield session