我从Johannes Farhenkrug的答案开始，它对我很有效。我需要模拟请求库，因为我的目标是隔离我的应用程序，不测试任何第三方资源。

然后我读了更多关于python的Mock库，我意识到我可以用python Mock类替换MockResponse类，你可能称之为“Test Double”或“Fake”。

这样做的好处是可以访问assert_called_with, call_args等。不需要额外的库。额外的好处，如“可读性”或“更python化”是主观的，所以它们可能对你有影响，也可能没有。

这是我的版本，更新使用python的Mock而不是test double:

import json
import requests
from unittest import mock

# defube stubs
AUTH_TOKEN = '{"prop": "value"}'
LIST_OF_WIDGETS = '{"widgets": ["widget1", "widget2"]}'
PURCHASED_WIDGETS = '{"widgets": ["purchased_widget"]}'


# exception class when an unknown URL is mocked
class MockNotSupported(Exception):
  pass


# factory method that cranks out the Mocks
def mock_requests_factory(response_stub: str, status_code: int = 200):
    return mock.Mock(**{
        'json.return_value': json.loads(response_stub),
        'text.return_value': response_stub,
        'status_code': status_code,
        'ok': status_code == 200
    })


# side effect mock function
def mock_requests_post(*args, **kwargs):
    if args[0].endswith('/api/v1/get_auth_token'):
        return mock_requests_factory(AUTH_TOKEN)
    elif args[0].endswith('/api/v1/get_widgets'):
        return mock_requests_factory(LIST_OF_WIDGETS)
    elif args[0].endswith('/api/v1/purchased_widgets'):
        return mock_requests_factory(PURCHASED_WIDGETS)
    
    raise MockNotSupported


# patch requests.post and run tests
with mock.patch('requests.post') as requests_post_mock:
  requests_post_mock.side_effect = mock_requests_post
  response = requests.post('https://myserver/api/v1/get_widgets')
  assert response.ok is True
  assert response.status_code == 200
  assert 'widgets' in response.json()
  
  # now I can also do this
  requests_post_mock.assert_called_with('https://myserver/api/v1/get_widgets')

Repl。它的链接:

https://repl.it/@abkonsta/Using-unittestMock-for-requestspost#main.py

https://repl.it/@abkonsta/Using-test-double-for-requestspost#main.py

这就是模拟请求的方法。Post，将其更改为HTTP方法

@patch.object(requests, 'post')
def your_test_method(self, mockpost):
    mockresponse = Mock()
    mockpost.return_value = mockresponse
    mockresponse.text = 'mock return'

    #call your target method now

你可以这样做(你可以按原样运行这个文件):

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()

重要提示:如果你的MyGreatClass类位于不同的包中，请输入my.great。你必须模仿my。great。Package。requests。get而不是request。get。在这种情况下，你的测试用例看起来像这样:

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()

享受吧!

对于pytest用户，有一个来自https://pypi.org/project/pytest-responsemock/的方便的fixture

例如，模拟GET到http://some.domain，你可以:

def test_me(response_mock):

    with response_mock('GET http://some.domain -> 200 :Nice'):
        response = send_request()
        assert result.ok
        assert result.content == b'Nice'

对于那些不想为pytest安装额外库的人，这里有一个例子。我将在这里复制一些扩展，基于上面的例子:

import datetime

import requests


class MockResponse:
    def __init__(self, json_data, status_code):
        self.json_data = json_data
        self.status_code = status_code
        self.elapsed = datetime.timedelta(seconds=1)

    # mock json() method always returns a specific testing dictionary
    def json(self):
        return self.json_data


def test_get_json(monkeypatch):
    # Any arguments may be passed and mock_get() will always return our
    # mocked object, which only has the .json() method.
    def mock_get(*args, **kwargs):
        return MockResponse({'mock_key': 'mock_value'}, 418)

    # apply the monkeypatch for requests.get to mock_get
    monkeypatch.setattr(requests, 'get', mock_get)

    # app.get_json, which contains requests.get, uses the monkeypatch
    response = requests.get('https://fakeurl')
    response_json = response.json()

    assert response_json['mock_key'] == 'mock_value'
    assert response.status_code == 418
    assert response.elapsed.total_seconds() == 1


============================= test session starts ==============================
collecting ... collected 1 item

test_so.py::test_get_json PASSED                                          [100%]

============================== 1 passed in 0.07s ===============================

使用requests_mock可以很容易地修补任何请求

pip install requests-mock

from unittest import TestCase
import requests_mock
from <yourmodule> import <method> (auth)

class TestApi(TestCase):
  @requests_mock.Mocker()
  def test_01_authentication(self, m):
        """Successful authentication using username password"""
        token = 'token'
        m.post(f'http://localhost/auth', json= {'token': token})
        act_token =auth("user", "pass")
        self.assertEqual(act_token, token)