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

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/

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()

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()

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