add banbanmini backend

talkingq-url/database/connection.py

@@ -0,0 +1,71 @@
+from sqlalchemy.ext.asyncio import create_async_engine, AsyncSession
+from sqlalchemy.orm import sessionmaker
+from config import settings
+from utils.logger import session_logger
+import asyncio
+import urllib.parse
+
+class DatabaseManager:
+    _instance = None
+    _lock = asyncio.Lock()
+    
+    def __init__(self):
+        self.engine = None
+        self.async_session = None
+        self._initialized = False
+    
+    @classmethod
+    async def get_instance(cls):
+        async with cls._lock:
+            if cls._instance is None:
+                cls._instance = DatabaseManager()
+            
+            if not cls._instance._initialized:
+                await cls._instance.initialize()
+                
+            return cls._instance
+    
+    async def initialize(self):
+        if self._initialized:
+            return
+            
+        try:
+            encoded_password = urllib.parse.quote_plus(settings.db_password)
+            connection_string = f"mysql+aiomysql://{settings.db_user}:{encoded_password}@{settings.db_host}:{settings.db_port}/{settings.db_name}?charset=utf8mb4"
+            self.engine = create_async_engine(
+                connection_string,
+                echo=settings.db_echo,
+                pool_pre_ping=True,
+                pool_recycle=3600,
+            )
+            
+            self.async_session = sessionmaker(
+                self.engine, expire_on_commit=False, class_=AsyncSession
+            )
+            
+            self._initialized = True
+            session_logger.info("system", "database", f"数据库连接初始化成功: {settings.db_host}:{settings.db_port}/{settings.db_name}")
+        except Exception as e:
+            session_logger.error("system", "database", f"数据库连接初始化失败: {str(e)}")
+            raise
+    
+    async def get_session(self):
+        """获取数据库会话"""
+        if not self._initialized:
+            await self.initialize()
+        return self.async_session()
+    
+    async def close(self):
+        """关闭数据库连接"""
+        if self.engine:
+            await self.engine.dispose()
+            self._initialized = False
+            session_logger.info("system", "database", "数据库连接已关闭")
+
+db_manager = None
+
+async def get_db_manager():
+    global db_manager
+    if db_manager is None:
+        db_manager = await DatabaseManager.get_instance()
+    return db_manager