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
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。
下面是一个带有请求响应类的解决方案。恕我直言,它更干净。
import json
from unittest.mock import patch
from requests.models import Response
def mocked_requests_get(*args, **kwargs):
response_content = None
request_url = kwargs.get('url', None)
if request_url == 'aurl':
response_content = json.dumps('a response')
elif request_url == 'burl':
response_content = json.dumps('b response')
elif request_url == 'curl':
response_content = json.dumps('c response')
response = Response()
response.status_code = 200
response._content = str.encode(response_content)
return response
@mock.patch('requests.get', side_effect=mocked_requests_get)
def test_fetch(self, mock_get):
response = requests.get(url='aurl')
assert ...
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/