如何模拟请求和响应？

Question

我正在尝试使用 Pythons 模拟包 来模拟 Pythons requests 模块。让我在以下情况下工作的基本电话是什么？

在我的views.py 中，我有一个函数可以进行各种requests.get() 调用，每次都有不同的响应

def myview(request):
  res1 = requests.get('aurl')
  res2 = request.get('burl')
  res3 = request.get('curl')

在我的测试类中，我想做这样的事情，但无法弄清楚确切的方法调用

步骤1：

 # Mock the requests module
# when mockedRequests.get('aurl') is called then return 'a response'
# when mockedRequests.get('burl') is called then return 'b response'
# when mockedRequests.get('curl') is called then return 'c response'

第2步：

呼唤我的观点

第 3 步：

验证响应包含“a 响应”、“b 响应”、“c 响应”

如何完成第 1 步（模拟请求模块）？

原文由 kk1957 发布，翻译遵循 CC BY-SA 4.0 许可协议

Answer 1

这对我有用：

 import mock
@mock.patch('requests.get', mock.Mock(side_effect = lambda k:{'aurl': 'a response', 'burl' : 'b response'}.get(k, 'unhandled request %s'%k)))

原文由 kk1957 发布，翻译遵循 CC BY-SA 3.0 许可协议

Answer 2

这是您可以执行此操作的方法（您可以按原样运行此文件）：

 import requests
import unittest
from unittest import mock

# This is the class we want to test
class MyGreatClass:
    def fetch_json(self, url):
        response = requests.get(url)
        return response.json()

# This method will be used by the mock to replace requests.get
def mocked_requests_get(*args, **kwargs):
    class MockResponse:
        def __init__(self, json_data, status_code):
            self.json_data = json_data
            self.status_code = status_code

        def json(self):
            return self.json_data

    if args[0] == 'http://someurl.com/test.json':
        return MockResponse({"key1": "value1"}, 200)
    elif args[0] == 'http://someotherurl.com/anothertest.json':
        return MockResponse({"key2": "value2"}, 200)

    return MockResponse(None, 404)

# Our test case class
class MyGreatClassTestCase(unittest.TestCase):

    # We patch 'requests.get' with our own method. The mock object is passed in to our test case method.
    @mock.patch('requests.get', side_effect=mocked_requests_get)
    def test_fetch(self, mock_get):
        # Assert requests.get calls
        mgc = MyGreatClass()
        json_data = mgc.fetch_json('http://someurl.com/test.json')
        self.assertEqual(json_data, {"key1": "value1"})
        json_data = mgc.fetch_json('http://someotherurl.com/anothertest.json')
        self.assertEqual(json_data, {"key2": "value2"})
        json_data = mgc.fetch_json('http://nonexistenturl.com/cantfindme.json')
        self.assertIsNone(json_data)

        # We can even assert that our mocked method was called with the right parameters
        self.assertIn(mock.call('http://someurl.com/test.json'), mock_get.call_args_list)
        self.assertIn(mock.call('http://someotherurl.com/anothertest.json'), mock_get.call_args_list)

        self.assertEqual(len(mock_get.call_args_list), 3)

if __name__ == '__main__':
    unittest.main()

重要说明： 如果你的 MyGreatClass 类位于不同的包中，比如 my.great.package ，你必须模拟 my.great.package.requests.get 而不仅仅是 ‘.request.get在那种情况下，您的测试用例将如下所示：

 import unittest
from unittest import mock
from my.great.package import MyGreatClass

# This method will be used by the mock to replace requests.get
def mocked_requests_get(*args, **kwargs):
    # Same as above

class MyGreatClassTestCase(unittest.TestCase):

    # Now we must patch 'my.great.package.requests.get'
    @mock.patch('my.great.package.requests.get', side_effect=mocked_requests_get)
    def test_fetch(self, mock_get):
        # Same as above

if __name__ == '__main__':
    unittest.main()

享受！

原文由 Johannes Fahrenkrug 发布，翻译遵循 CC BY-SA 3.0 许可协议