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

为了避免安装其他依赖项,您应该创建一个假响应。这个FakeResponse可以是Response的子类(我认为这是一个很好的方法,因为它更现实),或者只是一个具有您需要的属性的简单类。

简单的假类

class FakeResponse:
        status_code = None

        def __init__(self, *args, **kwargs):
            self.status_code = 500
            self.text = ""

回应之子

class FakeResponse(Response):
        encoding = False
        _content = None

        def __init__(*args, **kwargs):
            super(FakeResponse).__thisclass__.status_code = 500
            # Requests requires to be not be None, if not throws an exception
            # For reference: https://github.com/psf/requests/issues/3698#issuecomment-261115119
            super(FakeResponse).__thisclass__.raw = io.BytesIO()

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

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'

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()