我试图使用python模拟包来模拟python请求模块。让我在下面的场景中工作的基本调用是什么?
在views.py中,我有一个函数,它每次都以不同的响应进行各种request .get()调用
def myview(request):
res1 = requests.get('aurl')
res2 = request.get('burl')
res3 = request.get('curl')
在我的测试类中,我想做类似的事情,但不能确定确切的方法调用
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'
步骤2:
调用我的视图
步骤3:
验证响应包含'a response', 'b response', 'c response'
我如何完成第1步(模拟请求模块)?
您可以使用request -mock代替吗?
假设你的myview函数接受一个请求。Session对象,用它发出请求,并对输出做一些事情:
# mypackage.py
def myview(session):
res1 = session.get("http://aurl")
res2 = session.get("http://burl")
res3 = session.get("http://curl")
return f"{res1.text}, {res2.text}, {res3.text}"
# test_myview.py
from mypackage import myview
import requests
def test_myview(requests_mock):
# set up requests
a_req = requests_mock.get("http://aurl", text="a response")
b_req = requests_mock.get("http://burl", text="b response")
c_req = requests_mock.get("http://curl", text="c response")
# test myview behaviour
session = requests.Session()
assert myview(session) == "a response, b response, c response"
# check that requests weren't called repeatedly
assert a_req.called_once
assert b_req.called_once
assert c_req.called_once
assert requests_mock.call_count == 3
你也可以在Pytest之外的框架中使用requests_mock——文档非常棒。
只是一个有用的提示给那些仍然挣扎,从urllib或urllib2/urllib3转换到请求,并试图模拟一个响应-我在实现我的模拟时得到了一个稍微令人困惑的错误:
与请求。get(path, auth=HTTPBasicAuth('user', 'pass'), verify=False) as url:
AttributeError: __enter__
当然,如果我知道with如何工作(我不知道),我就会知道这是一个残留的、不必要的上下文(来自PEP 343)。在使用请求库时没有必要,因为它在底层为您做了基本相同的事情。只需删除with并使用bare requests.get(…),就万事大吉了。
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