Optimize database connection management in spider module, fix WebSocket handling and parameter validation.

utils/db_manager.py

@@ -0,0 +1,36 @@
+import pymysql
+from pymysql.cursors import DictCursor
+
+class DatabaseManager:
+    _instance = None
+    _connection = None
+    _config = None
+
+    def __new__(cls):
+        if cls._instance is None:
+            cls._instance = super(DatabaseManager, cls).__new__(cls)
+        return cls._instance
+
+    @classmethod
+    def initialize(cls, config):
+        """初始化数据库配置"""
+        cls._config = config
+
+    @classmethod
+    def get_connection(cls):
+        """获取数据库连接"""
+        if cls._connection is None or not cls._connection.open:
+            if cls._config is None:
+                raise ValueError("数据库未初始化，请先调用initialize方法设置配置")
+            cls._connection = pymysql.connect(
+                **cls._config,
+                cursorclass=DictCursor
+            )
+        return cls._connection
+
+    @classmethod
+    def close(cls):
+        """关闭数据库连接"""
+        if cls._connection and cls._connection.open:
+            cls._connection.close()
+            cls._connection = None