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)?


当前回答

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/

其他回答

我使用requests-mock为单独的模块编写测试:

# module.py
import requests

class A():

    def get_response(self, url):
        response = requests.get(url)
        return response.text

测试:

# tests.py
import requests_mock
import unittest

from module import A


class TestAPI(unittest.TestCase):

    @requests_mock.mock()
    def test_get_response(self, m):
        a = A()
        m.get('http://aurl.com', text='a response')
        self.assertEqual(a.get_response('http://aurl.com'), 'a response')
        m.get('http://burl.com', text='b response')
        self.assertEqual(a.get_response('http://burl.com'), 'b response')
        m.get('http://curl.com', text='c response')
        self.assertEqual(a.get_response('http://curl.com'), 'c response')

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

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

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 ===============================

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'