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)?
只是一个有用的提示给那些仍然挣扎,从urllib或urllib2/urllib3转换到请求,并试图模拟一个响应-我在实现我的模拟时得到了一个稍微令人困惑的错误:
与请求。get(path, auth=HTTPBasicAuth('user', 'pass'), verify=False) as url:
AttributeError: __enter__
当然,如果我知道with如何工作(我不知道),我就会知道这是一个残留的、不必要的上下文(来自PEP 343)。在使用请求库时没有必要,因为它在底层为您做了基本相同的事情。只需删除with并使用bare requests.get(…),就万事大吉了。
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()
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!
只是一个有用的提示给那些仍然挣扎,从urllib或urllib2/urllib3转换到请求,并试图模拟一个响应-我在实现我的模拟时得到了一个稍微令人困惑的错误:
与请求。get(path, auth=HTTPBasicAuth('user', 'pass'), verify=False) as url:
AttributeError: __enter__
当然,如果我知道with如何工作(我不知道),我就会知道这是一个残留的、不必要的上下文(来自PEP 343)。在使用请求库时没有必要,因为它在底层为您做了基本相同的事情。只需删除with并使用bare requests.get(…),就万事大吉了。
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()