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)?
目前最简单的方法:
from unittest import TestCase
from unittest.mock import Mock, patch
from .utils import method_foo
class TestFoo(TestCase):
@patch.object(utils_requests, "post") # change to desired method here
def test_foo(self, mock_requests_post):
# EXPLANATION: mocked 'post' method above will return some built-in mock,
# and its method 'json' will return mock 'mock_data',
# which got argument 'return_value' with our data to be returned
mock_data = Mock(return_value=[{"id": 1}, {"id": 2}])
mock_requests_post.return_value.json = mock_data
method_foo()
# TODO: asserts here
"""
Example of method that you can test in utils.py
"""
def method_foo():
response = requests.post("http://example.com")
records = response.json()
for record in records:
print(record.get("id"))
# do other stuff here
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 ===============================
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。
目前最简单的方法:
from unittest import TestCase
from unittest.mock import Mock, patch
from .utils import method_foo
class TestFoo(TestCase):
@patch.object(utils_requests, "post") # change to desired method here
def test_foo(self, mock_requests_post):
# EXPLANATION: mocked 'post' method above will return some built-in mock,
# and its method 'json' will return mock 'mock_data',
# which got argument 'return_value' with our data to be returned
mock_data = Mock(return_value=[{"id": 1}, {"id": 2}])
mock_requests_post.return_value.json = mock_data
method_foo()
# TODO: asserts here
"""
Example of method that you can test in utils.py
"""
def method_foo():
response = requests.post("http://example.com")
records = response.json()
for record in records:
print(record.get("id"))
# do other stuff here
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()