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)?
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 ===============================
我将演示如何通过将真正的请求与返回相同数据的假请求交换来将编程逻辑与实际的外部库分离。在你看来，如果外部api调用，那么这个过程是最好的
import pytest
from unittest.mock import patch
from django.test import RequestFactory
@patch("path(projectname.appname.filename).requests.post")
def test_mock_response(self, mock_get, rf: RequestFactory):
mock_get.return_value.ok = Mock(ok=True)
mock_get.return_value.status_code = 400
mock_get.return_value.json.return_value = {you can define here dummy response}
request = rf.post("test/", data=self.payload)
response = view_name_view(request)
expected_response = {
"success": False,
"status": "unsuccessful",
}
assert response.data == expected_response
assert response.status_code == 400
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
这对我来说是可行的，尽管我还没有做太多复杂的测试。
import json
from requests import Response
class MockResponse(Response):
def __init__(self,
url='http://example.com',
headers={'Content-Type':'text/html; charset=UTF-8'},
status_code=200,
reason = 'Success',
_content = 'Some html goes here',
json_ = None,
encoding='UTF-8'
):
self.url = url
self.headers = headers
if json_ and headers['Content-Type'] == 'application/json':
self._content = json.dumps(json_).encode(encoding)
else:
self._content = _content.encode(encoding)
self.status_code = status_code
self.reason = reason
self.encoding = encoding
然后你可以创建响应:
mock_response = MockResponse(
headers={'Content-Type' :'application/json'},
status_code=401,
json_={'success': False},
reason='Unauthorized'
)
mock_response.raise_for_status()
给了
requests.exceptions.HTTPError: 401 Client Error: Unauthorized for url: http://example.com
解决请求的一个可能的方法是使用库betamax，它记录所有的请求，之后如果你在相同的url中使用相同的参数发出请求，betamax将使用记录的请求，我一直在用它来测试网络爬虫，它节省了我很多时间。
import os
import requests
from betamax import Betamax
from betamax_serializers import pretty_json
WORKERS_DIR = os.path.dirname(os.path.abspath(__file__))
CASSETTES_DIR = os.path.join(WORKERS_DIR, u'resources', u'cassettes')
MATCH_REQUESTS_ON = [u'method', u'uri', u'path', u'query']
Betamax.register_serializer(pretty_json.PrettyJSONSerializer)
with Betamax.configure() as config:
config.cassette_library_dir = CASSETTES_DIR
config.default_cassette_options[u'serialize_with'] = u'prettyjson'
config.default_cassette_options[u'match_requests_on'] = MATCH_REQUESTS_ON
config.default_cassette_options[u'preserve_exact_body_bytes'] = True
class WorkerCertidaoTRT2:
session = requests.session()
def make_request(self, input_json):
with Betamax(self.session) as vcr:
vcr.use_cassette(u'google')
response = session.get('http://www.google.com')
https://betamax.readthedocs.io/en/latest/
