# -*- coding: utf-8 -*- # Copyright (c) Alibaba, Inc. and its affiliates. import threading from typing import Optional import requests from requests.adapters import HTTPAdapter from dashscope.common.logging import logger class ConnectionPoolConfig: """ 连接池配置类 提供类型安全和参数验证的配置方式 """ def __init__( self, pool_connections: int = 10, pool_maxsize: int = 20, max_retries: int = 3, pool_block: bool = False, ): """ 初始化连接池配置 Args: pool_connections: 连接池大小，默认 10 - 低并发（< 10 req/s）: 10 - 中并发（10-50 req/s）: 20-30 - 高并发（> 50 req/s）: 50-100 pool_maxsize: 最大连接数，默认 20 - 应该 >= pool_connections - 低并发: 20 - 中并发: 50 - 高并发: 100-200 max_retries: 重试次数，默认 3 - 网络稳定: 3 - 网络不稳定: 5-10 pool_block: 连接池满时是否阻塞，默认 False - False: 连接池满时创建新连接（推荐） - True: 连接池满时等待可用连接 """ # 参数验证 if pool_connections < 1: raise ValueError("pool_connections 必须 >= 1") if pool_maxsize < pool_connections: raise ValueError("pool_maxsize 必须 >= pool_connections") if max_retries < 0: raise ValueError("max_retries 必须 >= 0") self.pool_connections = pool_connections self.pool_maxsize = pool_maxsize self.max_retries = max_retries self.pool_block = pool_block def to_dict(self): """转换为字典格式""" return { "pool_connections": self.pool_connections, "pool_maxsize": self.pool_maxsize, "max_retries": self.max_retries, "pool_block": self.pool_block, } def __repr__(self): return ( f"ConnectionPoolConfig(" f"pool_connections={self.pool_connections}, " f"pool_maxsize={self.pool_maxsize}, " f"max_retries={self.max_retries}, " f"pool_block={self.pool_block})" ) class SessionManager: """ 全局 HTTP Session 管理器 特性： 1. 线程安全的 Session 池 2. 支持全局启用/禁用连接复用 3. 支持自定义 Session 配置 4. 自动清理和重建机制 """ _instance = None _lock = threading.Lock() def __init__(self): self._enabled = False # 默认关闭，保持向后兼容 self._session = None self._session_lock = threading.RLock() self._config = ConnectionPoolConfig() # 使用配置类 @classmethod def get_instance(cls): """单例模式获取实例""" if cls._instance is None: with cls._lock: if cls._instance is None: cls._instance = cls() return cls._instance @classmethod def reset_instance(cls): """ 重置单例实例（仅用于测试） 警告：此方法仅应在测试环境中使用 """ with cls._lock: if cls._instance is not None: cls._instance.disable() cls._instance.reset() cls._instance = None def enable( self, pool_connections: Optional[int] = None, pool_maxsize: Optional[int] = None, max_retries: Optional[int] = None, pool_block: Optional[bool] = None, ): """ 启用连接复用 Args: pool_connections: 连接池大小，默认 10 pool_maxsize: 最大连接数，默认 20 max_retries: 重试次数，默认 3 pool_block: 连接池满时是否阻塞，默认 False Examples: # 使用默认配置 enable() # 使用命名参数 enable(pool_connections=50, pool_maxsize=100) """ with self._session_lock: # 使用命名参数更新配置 if pool_connections is not None: self._config.pool_connections = pool_connections if pool_maxsize is not None: self._config.pool_maxsize = pool_maxsize if max_retries is not None: self._config.max_retries = max_retries if pool_block is not None: self._config.pool_block = pool_block # 参数验证 if self._config.pool_maxsize < self._config.pool_connections: raise ValueError( f"pool_maxsize ({self._config.pool_maxsize}) 必须 >= " f"pool_connections ({self._config.pool_connections})", ) self._enabled = True self._ensure_session() logger.info( "HTTP connection pool enabled with config: %s", self._config, ) def disable(self): """禁用连接复用，关闭现有 Session""" with self._session_lock: self._enabled = False if self._session: try: self._session.close() except Exception as e: logger.warning("Error closing session: %s", e) finally: self._session = None logger.info("HTTP connection pool disabled") def is_enabled(self): """检查是否启用连接复用""" return self._enabled def get_config(self) -> ConnectionPoolConfig: """ 获取当前连接池配置 Returns: ConnectionPoolConfig: 当前配置对象 """ return self._config def has_active_session(self) -> bool: """ 检查是否有活跃的 Session Returns: bool: 如果存在活跃的 Session 返回 True，否则返回 False """ with self._session_lock: return self._session is not None def _ensure_session(self): """确保 Session 存在且有效（需要持有锁）""" if self._session is None: self._session = requests.Session() # 配置连接池 adapter = HTTPAdapter( pool_connections=self._config.pool_connections, pool_maxsize=self._config.pool_maxsize, max_retries=self._config.max_retries, pool_block=self._config.pool_block, ) self._session.mount("http://", adapter) self._session.mount("https://", adapter) logger.debug("Created new HTTP session with connection pool") def get_session(self) -> Optional[requests.Session]: """ 获取 Session 对象 Returns: 如果启用了连接复用，返回全局 Session 否则返回 None Examples: >>> manager = SessionManager.get_instance() >>> manager.enable() >>> session = manager.get_session() >>> if session: ... response = session.get(url) """ if not self._enabled: return None with self._session_lock: self._ensure_session() return self._session def reset(self): """重置 Session（用于处理连接问题）""" with self._session_lock: if self._session: try: self._session.close() except Exception as e: logger.warning("Error closing session during reset: %s", e) finally: self._session = None if self._enabled: self._ensure_session() logger.info("HTTP connection pool reset") def configure( self, pool_connections: Optional[int] = None, pool_maxsize: Optional[int] = None, max_retries: Optional[int] = None, pool_block: Optional[bool] = None, ): """ 更新配置并重建 Session Args: pool_connections: 连接池大小 pool_maxsize: 最大连接数 max_retries: 重试次数 pool_block: 连接池满时是否阻塞 Examples: # 调整单个参数 configure(pool_maxsize=100) # 调整多个参数 configure(pool_connections=50, pool_maxsize=100) """ with self._session_lock: # 使用命名参数更新配置 if pool_connections is not None: self._config.pool_connections = pool_connections if pool_maxsize is not None: self._config.pool_maxsize = pool_maxsize if max_retries is not None: self._config.max_retries = max_retries if pool_block is not None: self._config.pool_block = pool_block # 参数验证 if self._config.pool_maxsize < self._config.pool_connections: raise ValueError( f"pool_maxsize ({self._config.pool_maxsize}) 必须 >= " f"pool_connections ({self._config.pool_connections})", ) if self._enabled: # 重建 Session 以应用新配置 if self._session: try: self._session.close() except Exception as e: logger.warning( "Error closing session during configure: %s", e, ) finally: self._session = None self._ensure_session() logger.info("HTTP connection pool configured: %s", self._config)