feat: 启动时检查数据库连接

app/main.py

@@ -15,13 +15,16 @@ from app.controller.add_graph_proxy_route import add_graph_proxy_route
 from app.routes import routes
 from app.utils.get_local_ips import get_local_ips
 from app.utils.llm_utils import create_llm
+from app.utils.mysql_utils import check_database_connection
 
 
 @asynccontextmanager
 async def lifespan(app: FastAPI):
   print(f"应用启动：{datetime.datetime.now().strftime('%Y-%m-%d %H:%M:%S')}")
+  async_engine = await check_database_connection()
   yield
   print(f"应用销毁：{datetime.datetime.now().strftime('%Y-%m-%d %H:%M:%S')}")
+  await async_engine.dispose()
 
 
 app = FastAPI(

app/utils/mysql_utils.py

@@ -0,0 +1,63 @@
+from typing import Annotated
+
+from fastapi.params import Depends
+from sqlalchemy import text
+from sqlalchemy.ext.asyncio import create_async_engine, AsyncSession
+from sqlalchemy.orm import sessionmaker
+
+from app.config.env import env
+
+DATABASE_URL = f"mysql+asyncmy://{env.db_username}:{env.db_password}@{env.db_host}:{env.db_port}/{env.db_database}?charset=utf8mb4"
+
+async_engine = create_async_engine(
+  DATABASE_URL,
+  # 连接池保持的连接数
+  pool_size=5,
+  # 允许超过pool_size的最大连接数
+  max_overflow=10,
+  # 获取连接的超时时间(秒)
+  pool_timeout=5,
+  # 连接回收时间(秒)
+  pool_recycle=60,  # 针对 Docker NAT 环境优化
+  # 启用连接有效性检测
+  pool_pre_ping=True,
+  # 启用SQL语句日志输出，便于开发调试
+  echo=True,
+  # 启用SQLAlchemy 2.0风格的未来模式API
+  future=True,
+)
+
+# 使用这个 Session 工厂
+async_session = sessionmaker(
+  async_engine,
+  class_=AsyncSession,
+  expire_on_commit=False
+)
+
+
+# 作用：用于在接口中注入得到会话实例对象session，在接口执行完毕之后，自动执行close动作关闭会话
+async def get_async_session() -> AsyncSession:
+  async with async_session() as session:
+    yield session
+
+
+# 作为类型使用，直接在接口参数中注入得到session会话实例对象
+AsyncSessionDep = Annotated[AsyncSession, Depends(get_async_session)]
+
+
+# 用于启动服务的时候检查数据库连接是否正常
+async def check_database_connection():
+  """检查数据库连接是否正常"""
+  try:
+    async with async_engine.begin() as conn:
+      print("Connecting Mysql...")
+      await conn.execute(text("select 1"))
+      # 打印连接成功信息及连接URL
+      print("✅ MySql connection successful：", DATABASE_URL)
+  except Exception as e:
+    # 打印连接失败信息及错误详情
+    print(f"❌ Database connection failed: {e}")
+    # 重新抛出异常，让上层处理
+    raise e
+
+  return async_engine