How can I mock a post inside a method, so i can have unittests?
def send_report(self, data):
url = settings.WEBHOOK_PO
payload = json.dumps(data)
requests.post(url, data=payload)
url = settings.WEBHOOK_LQA
response = requests.post(url, data=payload)
return response.status_code
Is there a way to cover this method for unit test with not actually posting?
You can use the mock library to replace requests.post with something else:
with mock.patch('requests.post') as mock_post:
foo.send_report(data)
(mock is a third-party package, but was added to the standard library, as part of the unittest package`, in Python 3.3.)
mock_post can be configured to provide the desired behavior during the test; consult the mock documentation for details.
Another option is to modify your method to take the post function as an argument, rather than hard-coding the function (this is an example of dependency injection):
def send_report(self, data, poster=requests.post):
url = settings.WEBHOOK_PO
payload = json.dumps(data)
poster(url, data=payload)
url = settings.WEBHOOK_LQA
response = poster(url, data=payload)
return response.status_code
When you want to test the function, you simply pass a different callable object as the optional second argument.
Note that you can supply separate functions for the two types of posts, which might make it easier to test than with a mock:
from functools import partial
def send_report(self,
data,
post_po=partial(requests.post, settings.WEBHOOK_PO),
post_lqa=partial(requests.post, settings.WEBHOOK_LQA)):
payload = json.dumps(data)
post_po(data=payload)
response = post_lqa(data=payload)
return response.status_code
Related
I' trying to properly test this simple function:
def get_content_from_header(request, header_name):
try:
content = request.headers[header_name]
except KeyError:
logging.error(f"BAD REQUEST: '{header_name}' header is missing from the request.")
except AttributeError:
logging.error(f"BAD REQUEST: request has no attributes 'headers'.")
else:
return content
return None
So this is my code so far, I'm using parametrize along with fixture to achieve my goal:
import main
import pytest
class ValidRequest:
def __init__(self):
self.headers = {
'Authorization': 'test_auth'
}
#pytest.fixture
def mocked_request():
request = ValidRequest()
return request
#pytest.mark.parametrize("possible_input, expected_output",
[('Authorization', 'test_auth'),
('InvalidHeader', None)])
def test_get_content_from_header(mocked_request, possible_input, expected_output):
# Run the function with mocked request
assert main.get_content_from_header(mocked_request, possible_input) == expected_output
Here's my problem: I only test the second parameter of the function get_content_from_header, not request which is the first one. How could I properly do that ?
Should I create a new class InvalidRequest and test my function with this new class in a new testing function just below test_get_content_from_header ?
Or should I add this new parameter trough parametrize in the existing testing function ?
What is the cleanest (more pythonic) way to do it ?
I would suggest a little change here, lets simplify that function a bit. Since that we are getting a certain header from the headers dict of the request we can just pass just the headers dict instead of the whole request.
def get_content_from_header(headers: dict, header_name: str):
if header_name in headers.keys():
return headers[header_name]
return None
This works the same way as your function, and you do not have to test your request parameter. Now you can test that in a very simple manner:
def test_get_content_from_header_returning_header_value():
headers = {"Authorization": "test_auth"}
assert get_content_from_header(headers, "Authorization") == "test_auth"
def test_get_content_from_header_returning_none():
headers = {"Authorization": None}
assert get_content_from_header(headers, "Authorization") == None
Now you don't need to test your request in that test, you can refer to https://flask.palletsprojects.com/en/2.0.x/testing/ and more specifically the client usage and test your endpoints, to test your request param.
Now about the loggers, I will usually place those in the place where you actually call the get_content_from_header function.
I have http get method mocked so to get the response from the url without actually sending the url:
def get(url, retries=None, back_off_factor=None, max_back_off=None, timeout=None, response_encoding=None,
retry_on_timeout=None, retry_codes=None, **kwargs):
return _make_request("GET", url,
retries=retries, back_off_factor=back_off_factor,
max_back_off=max_back_off,
timeout=timeout,
response_encoding=response_encoding,
retry_on_timeout=retry_on_timeout,
retry_codes=retry_codes,
**kwargs)
#patch('lib.httputil.get')
def test_harvest(self, mock_get):
articles = json.load(json_file)
# Configure the mock to return a response with an OK status code. Also, the mock should have
# a `json()` method that returns a list of todos.
mock_get.return_value = Mock(ok=True)
mock_get.return_value.json.return_value = articles
mock_get.return_value.status_code = 200
the_rest_of_the_test()
But I realized I need to mock it only if the URL is specific. I know I could use new keyword and do:
def mock_get(self, url):
if url == MY_SPECIFIC_URL:
{...}
else:
self.old_get(url)
{...}
with mock.patch('portality.lib.httputil.get', new=self.mock_get):
the_rest_of_the_test()
but I don't really know how to mock the Response object so that it returns the correct status code and gives the correct result to .json() method.
How can I use both of these approaches altogether so that on one hand I can use the conditional but on the other mock the Response in easy way?
I suggest that you use the requests library, along with responses which is specifically meant for returning the desired HTTP responses.
You can mock specific urls:
import responses
import requests
#responses.activate
def test_simple():
responses.add(responses.GET, 'http://twitter.com/api/1/foobar',
json={'error': 'not found'}, status=404)
resp = requests.get('http://twitter.com/api/1/foobar')
assert resp.json() == {"error": "not found"}
assert len(responses.calls) == 1
assert responses.calls[0].request.url == 'http://twitter.com/api/1/foobar'
assert responses.calls[0].response.text == '{"error": "not found"}'
And you can exclude other urls:
responses.add_passthru(re.compile('https://percy.io/\\w+'))
I have to test out a certain view that gets certain information from request.args.
I can't mock this since a lot of stuff in the view uses the request object.
The only alternative I can think of is to manually set request.args.
I can do that with the test_request_context(), e.g:
with self.app.test_request_context() as req:
req.request.args = {'code': 'mocked access token'}
MyView()
Now the request inside this view will have the arguments that I've set.
However I need to call my view, not just initialize it, so I use this:
with self.app.test_client() as c:
resp = c.get('/myview')
But I don't know how to manipulate the request arguments in this manner.
I have tried this:
with self.app.test_client() as c:
with self.app.test_request_context() as req:
req.request.args = {'code': 'mocked access token'}
resp = c.get('/myview')
but this does not set request.args.
Pass the query_string argument to c.get, which can either be a dict, a MultiDict, or an already encoded string.
with app.test_client() as c:
r = c.get('/', query_string={'name': 'davidism'})
The test client request methods pass their arguments to Werkzeug's EnvironBuilder, which is where this is documented.
So, I've just started using mock with a Django project. I'm trying to mock out part of a view which makes a request to a remote API to confirm a subscription request was genuine (a form of verification as per the spec I'm working to).
What I have resembles:
class SubscriptionView(View):
def post(self, request, **kwargs):
remote_url = request.POST.get('remote_url')
if remote_url:
response = requests.get(remote_url, params={'verify': 'hello'})
if response.status_code != 200:
return HttpResponse('Verification of request failed')
What I now want to do is to use mock to mock out the requests.get call to change the response, but I can't work out how to do this for the patch decorator. I'd thought you do something like:
#patch(requests.get)
def test_response_verify(self):
# make a call to the view using self.app.post (WebTest),
# requests.get makes a suitable fake response from the mock object
How do I achieve this?
You're almost there. You're just calling it slightly incorrectly.
from mock import call, patch
#patch('my_app.views.requests')
def test_response_verify(self, mock_requests):
# We setup the mock, this may look like magic but it works, return_value is
# a special attribute on a mock, it is what is returned when it is called
# So this is saying we want the return value of requests.get to have an
# status code attribute of 200
mock_requests.get.return_value.status_code = 200
# Here we make the call to the view
response = SubscriptionView().post(request, {'remote_url': 'some_url'})
self.assertEqual(
mock_requests.get.call_args_list,
[call('some_url', params={'verify': 'hello'})]
)
You can also test that the response is the correct type and has the right content.
It's all in the documentation:
patch(target, new=DEFAULT, spec=None, create=False, spec_set=None, autospec=None, new_callable=None, **kwargs)
target should be a string in the form ‘package.module.ClassName’.
from mock import patch
# or #patch('requests.get')
#patch.object(requests, 'get')
def test_response_verify(self):
# make a call to the view using self.app.post (WebTest),
# requests.get makes a suitable fake response from the mock object
I am writing an application that performs REST operations using Kenneth Reitz's requests library and I'm struggling to find a nice way to unit test these applications, because requests provides its methods via module-level methods.
What I want is the ability to synthesize the conversation between the two sides; provide a series of request assertions and responses.
It is in fact a little strange that the library has a blank page about end-user unit testing, while targeting user-friendliness and ease of use. There's however an easy-to-use library by Dropbox, unsurprisingly called responses. Here is its intro post. It says they've failed to employ httpretty, while stating no reason of the fail, and written a library with similar API.
import unittest
import requests
import responses
class TestCase(unittest.TestCase):
#responses.activate
def testExample(self):
responses.add(**{
'method' : responses.GET,
'url' : 'http://example.com/api/123',
'body' : '{"error": "reason"}',
'status' : 404,
'content_type' : 'application/json',
'adding_headers' : {'X-Foo': 'Bar'}
})
response = requests.get('http://example.com/api/123')
self.assertEqual({'error': 'reason'}, response.json())
self.assertEqual(404, response.status_code)
If you use specifically requests try httmock. It's wonderfully simple and elegant:
from httmock import urlmatch, HTTMock
import requests
# define matcher:
#urlmatch(netloc=r'(.*\.)?google\.com$')
def google_mock(url, request):
return 'Feeling lucky, punk?'
# open context to patch
with HTTMock(google_mock):
# call requests
r = requests.get('http://google.com/')
print r.content # 'Feeling lucky, punk?'
If you want something more generic (e.g. to mock any library making http calls) go for httpretty.
Almost as elegant:
import requests
import httpretty
#httpretty.activate
def test_one():
# define your patch:
httpretty.register_uri(httpretty.GET, "http://yipit.com/",
body="Find the best daily deals")
# use!
response = requests.get('http://yipit.com')
assert response.text == "Find the best daily deals"
HTTPretty is far more feature-rich - it offers also mocking status code, streaming responses, rotating responses, dynamic responses (with a callback).
You could use a mocking library such as Mocker to intercept the calls to the requests library and return specified results.
As a very simple example, consider this class which uses the requests library:
class MyReq(object):
def doSomething(self):
r = requests.get('https://api.github.com', auth=('user', 'pass'))
return r.headers['content-type']
Here's a unit test that intercepts the call to requests.get and returns a specified result for testing:
import unittest
import requests
import myreq
from mocker import Mocker, MockerTestCase
class MyReqTests(MockerTestCase):
def testSomething(self):
# Create a mock result for the requests.get call
result = self.mocker.mock()
result.headers
self.mocker.result({'content-type': 'mytest/pass'})
# Use mocker to intercept the call to requests.get
myget = self.mocker.replace("requests.get")
myget('https://api.github.com', auth=('user', 'pass'))
self.mocker.result(result)
self.mocker.replay()
# Now execute my code
r = myreq.MyReq()
v = r.doSomething()
# and verify the results
self.assertEqual(v, 'mytest/pass')
self.mocker.verify()
if __name__ == '__main__':
unittest.main()
When I run this unit test I get the following result:
.
----------------------------------------------------------------------
Ran 1 test in 0.004s
OK
Missing from these answers is requests-mock.
From their page:
>>> import requests
>>> import requests_mock
As a context manager:
>>> with requests_mock.mock() as m:
... m.get('http://test.com', text='data')
... requests.get('http://test.com').text
...
'data'
Or as a decorator:
>>> #requests_mock.mock()
... def test_func(m):
... m.get('http://test.com', text='data')
... return requests.get('http://test.com').text
...
>>> test_func()
'data'
using mocker like in srgerg's answer:
def replacer(method, endpoint, json_string):
from mocker import Mocker, ANY, CONTAINS
mocker = Mocker()
result = mocker.mock()
result.json()
mocker.count(1, None)
mocker.result(json_string)
replacement = mocker.replace("requests." + method)
replacement(CONTAINS(endpoint), params=ANY)
self.mocker.result(result)
self.mocker.replay()
For the requests library, this would intercept the request by method and endpoint you're hitting and replace the .json() on the response with the json_string passed in.
If you break out your response handler/parser into a separate function, you can work with requests.Response objects directly, without needing to mock the client-server interaction.
Code under test
from xml.dom import minidom
from requests.models import Response
def function_under_test(s3_response: Response):
doc = minidom.parseString(s3_response.text)
return (
s3_response.status_code,
doc.getElementsByTagName('Code').item(0).firstChild.data,
)
Test code
import unittest
from io import BytesIO
class Test(unittest.TestCase):
def test_it(self):
s3_response = Response()
s3_response.status_code = 404
s3_response.raw = BytesIO(b"""<?xml version="1.0" encoding="UTF-8"?>
<Error>
<Code>NoSuchKey</Code>
<Message>The resource you requested does not exist</Message>
<Resource>/mybucket/myfoto.jpg</Resource>
<RequestId>4442587FB7D0A2F9</RequestId>
</Error>
""")
parsed_response = function_under_test(s3_response)
self.assertEqual(404, parsed_response[0])
self.assertEqual("NoSuchKey", parsed_response[1])
There's a library for this, if you want to write your test server with Flask: requests-flask-adaptor
You just have to be careful with the order of imports when monkeypatching.