如何通过Mock补丁为指定类的requests.Session请求添加认证参数

你的现有代码问题在于patch路径错误，且未对请求发起者做区分。以下是两种可行的实现方案，无需修改第三方库代码：

方案一：通过调用栈识别调用者，动态添加认证 #

利用inspect模块追踪调用栈，判断发起请求的实例是否属于目标类，仅对FirstClass的请求追加认证参数。

from unittest.mock import patch
import requests
import inspect

class FirstClass:
    def make_request(self, url, headers=None):
        with requests.Session() as session:
            response = session.get(url, headers=headers)
            return response

class SecondClass:
    def make_request(self, url, headers=None):
        with requests.Session() as session:
            response = session.get(url, headers=headers)
            return response

def patched_get(self, url, **kwargs):
    # 遍历调用栈，找到发起请求的类实例
    stack = inspect.stack()
    for frame_info in stack:
        local_vars = frame_info.frame.f_locals
        if 'self' in local_vars:
            caller_instance = local_vars['self']
            # 仅为FirstClass的请求添加基础认证
            if isinstance(caller_instance, FirstClass):
                kwargs['auth'] = ('your_username', 'your_password')
            break
    # 调用原始的get方法执行请求
    return original_get(self, url, **kwargs)

# 保存原始的Session.get方法
original_get = requests.Session.get

# 测试时patch requests.Session.get
with patch.object(requests.Session, 'get', side_effect=patched_get):
    first = FirstClass()
    second = SecondClass()
    
    # FirstClass的请求会自动携带认证
    first.make_request("https://httpbin.org/basic-auth/your_username/your_password")
    # SecondClass的请求无认证
    second.make_request("https://httpbin.org/status/200")

方案二：Patch Session构造，针对目标类返回带认证的Session #

替换requests.Session的构造逻辑，当检测到是FirstClass创建Session时，自动为其设置认证属性，后续所有请求都会携带认证信息。

from unittest.mock import patch
import requests
import inspect

class FirstClass:
    def make_request(self, url, headers=None):
        with requests.Session() as session:
            response = session.get(url, headers=headers)
            return response

class SecondClass:
    def make_request(self, url, headers=None):
        with requests.Session() as session:
            response = session.get(url, headers=headers)
            return response

def patched_session():
    session = requests.Session()
    # 追踪调用栈判断创建Session的实例所属类
    stack = inspect.stack()
    for frame_info in stack:
        local_vars = frame_info.frame.f_locals
        if 'self' in local_vars:
            caller_instance = local_vars['self']
            if isinstance(caller_instance, FirstClass):
                session.auth = ('your_username', 'your_password')
            break
    return session

# 测试时patch requests.Session构造方法
with patch('requests.Session', side_effect=patched_session):
    first = FirstClass()
    second = SecondClass()
    
    first.make_request("https://httpbin.org/basic-auth/your_username/your_password")
    second.make_request("https://httpbin.org/status/200")

注意事项 #

• 调用栈遍历逻辑可根据第三方库的实际代码结构调整，确保能准确识别FirstClass的调用上下文。
• 若目标类使用了其他请求方法（如post），只需对对应的Session.post方法做同样的patch处理即可。

内容的提问来源于stack exchange，提问作者Auggers