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)?
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
尝试使用响应库。以下是他们文档中的一个例子:
import responses
import requests
@responses.activate
def test_simple():
responses.add(responses.GET, 'http://twitter.com/api/1/foobar',
json={'error': 'not found'}, status=404)
resp = requests.get('http://twitter.com/api/1/foobar')
assert resp.json() == {"error": "not found"}
assert len(responses.calls) == 1
assert responses.calls[0].request.url == 'http://twitter.com/api/1/foobar'
assert responses.calls[0].response.text == '{"error": "not found"}'
相比于自己设置所有的mock，它提供了相当好的便利。
还有HTTPretty:
它不是特定于请求库，在某些方面更强大，尽管我发现它不太适合检查它拦截的请求，而响应则很容易
还有httmock。
最近，一个比古老的请求更受欢迎的新库是httpx，它增加了对异步的一等支持。httpx的模拟库是:https://github.com/lundberg/respx
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!
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/
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
