feat: init project

app/utils/db_utils.py

@@ -0,0 +1,62 @@
+import asyncio
+import sys
+from contextlib import asynccontextmanager
+from typing import Annotated, AsyncContextManager
+
+from fastapi.params import Depends
+from langgraph.checkpoint.postgres.aio import AsyncPostgresSaver
+from sqlalchemy import AsyncAdaptedQueuePool, text
+from sqlalchemy.ext.asyncio import AsyncEngine
+from sqlalchemy.orm import sessionmaker
+from sqlmodel.ext.asyncio.session import AsyncSession
+
+from app.config.env import env
+from sqlmodel import create_engine
+
+DATABASE_URL = f"mysql+asyncmy://{env.db_username}:{env.db_password}@{env.db_host}:{env.db_port}/{env.db_database}?charset=utf8mb4"
+
+# 创建异步引擎实例，用于异步操作数据库
+async_engine = AsyncEngine(create_engine(
+  DATABASE_URL,
+  poolclass=AsyncAdaptedQueuePool,  # 使用异步适配的队列池
+  pool_size=5,  # 连接池保持的连接数
+  max_overflow=10,  # 允许超过pool_size的最大连接数
+  pool_timeout=30,  # 获取连接的超时时间(秒)
+  pool_recycle=3600,  # 连接回收时间(秒)
+  echo=True,  # 启用SQL语句日志输出，便于开发调试
+  future=True,  # 启用SQLAlchemy 2.0风格的未来模式API
+))
+
+# 创建一个会话工厂函数
+async_session = sessionmaker(
+  bind=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
+
+
+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("✅ Database 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