Python3.10.9容器中eventlet打补丁引发requests递归错误求助

问题场景 #

在Python 3.10.9的Docker容器中，应用依赖eventlet.monkey_patch(socket=True)，调用requests.Session().get()时出现RecursionError: maximum recursion depth exceeded错误。复现代码如下：

import requests
from requests.adapters import HTTPAdapter

s = requests.Session()
s.mount('https://', HTTPAdapter(pool_connections=2))
s.get('https://stackoverflow.com/questions/34837026/whats-the-meaning-of-pool-connections-in-requests-adapters-httpadapter')
# <Response [200]>

import eventlet
eventlet.monkey_patch(socket=True)

s.get('https://stackoverflow.com/questions/34837026/whats-the-meaning-of-pool-connections-in-requests-adapters-httpadapter')
# <Response [200]>

s.get('https://www.google.com/')
# RecursionError: maximum recursion depth exceeded

s.get('https://stackoverflow.com/questions/34837026/whats-the-meaning-of-pool-connections-in-requests-adapters-httpadapter')
# <Response [200]>

可行兼容方案 #

方案1：提前执行monkey_patch #

将eventlet.monkey_patch(socket=True)放在所有requests相关导入和Session初始化之前执行，让requests从一开始就使用eventlet打补丁后的socket实现，避免新旧逻辑冲突。修改后代码：

import eventlet
eventlet.monkey_patch(socket=True)

import requests
from requests.adapters import HTTPAdapter

s = requests.Session()
s.mount('https://', HTTPAdapter(pool_connections=2))
s.get('https://stackoverflow.com/questions/34837026/whats-the-meaning-of-pool-connections-in-requests-adapters-httpadapter')
s.get('https://www.google.com/')  # 正常返回响应

方案2：打补丁后重置HTTPAdapter #

如果无法提前执行monkey_patch，可在打补丁后重新创建并挂载HTTPAdapter，替换掉之前绑定原生socket的旧适配器：

import requests
from requests.adapters import HTTPAdapter

s = requests.Session()
s.mount('https://', HTTPAdapter(pool_connections=2))
s.get('https://stackoverflow.com/questions/34837026/whats-the-meaning-of-pool-connections-in-requests-adapters-httpadapter')

import eventlet
eventlet.monkey_patch(socket=True)

# 重置适配器，让Session使用补丁后的socket
s.mount('https://', HTTPAdapter(pool_connections=2))

s.get('https://www.google.com/')  # 正常执行
s.get('https://stackoverflow.com/questions/34837026/whats-the-meaning-of-pool-connections-in-requests-adapters-httpadapter')  # 正常执行

问题本质 #

递归错误源于：monkey_patch前，HTTPAdapter已初始化并绑定了原生socket的连接逻辑；打补丁后eventlet替换了socket实现，但旧适配器仍在调用原生方法，而原生方法被补丁逻辑劫持，形成循环调用，最终触发递归深度超限。

内容的提问来源于stack exchange，提问作者oliver nadj