Why does my mocking of an URL with requests not work? - python

I tried to mock a specific URL as shown in this example:
How can I mock requests and the response?
to test my own function:
class URLStatus():
#staticmethod
def check(url, redirects):
try:
session = requests.Session()
session.max_redirects = redirects
urlcheck = session.get(url)
return urlcheck.status_code
The issue is that it never takes the mocked url, but instead only takes real ones.
import requests
from unittest import TestCase, mock
from unittest.mock import patch
from lib.checks.url_status import URLStatus
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)
class URLStatusTestCase(TestCase):
#mock.patch('lib.checks.url_status.requests.get', side_effect=mocked_requests_get)
def test_check(self, mock_get):
url_status = URLStatus()
test_data = url_status.check('http://someurl.com/test.json', 5)
self.assertEqual(test_data, 200)
if __name__ == '__main__':
unittest.main()
This one, for example, fails because it sees 'http://someurl.com/test.json' as a 404, not a 200. I have no idea why this is happening.
How do I make it take the mocked URL?

You are mocking the wrong function. requests.get is a convenience function that creates its own, one-use Session, then uses its get method to provide the result. Your check method is using its own Session object; you need to at least mock that object's get method.
Given that you aren't reusing this session elsewhere, it would probably be simplest to change its implementation to take advantage of requests.get:
class URLStatus():
#staticmethod
def check(url, redirects):
return requests.get(url, max_redirects=redirects).status_code

Related

Conditionally mock httputil.get method on specific url with path json

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+'))

How to write unit tests using MOCKS that that test the endpoint

I wrote an endpoint that calls an API to get the time of day for a timezone defined by the user. Now I need to Mock this endpoint but I am having trouble coming up with the correct answer. Here is the code that I wrote:
Im not quite sure what I am suppose to call to get a response.
import requests
import json
import jsonpath
import dateutil
from flask import Flask, render_template, request
from flask import jsonify, make_response
app = Flask(__name__, template_folder="templates")
#app.route('/get_time', methods=['GET'])
def get_time():
try:
time_zone = request.args.get('time_zone')
url = "http://worldclockapi.com/api/json/" + time_zone + "/now"
r = requests.get(url)
except Exception:
return make_response(jsonify({"Error": "Some error message"}), 400)
return r.json()["currentDateTime"]
if response.status_code != 200:
print("Error on response")
return response.status_code, response.text
if __name__ == '__main__':
app.run(debug=True)
This is what I have for the Test:
import json
import unittest
import unittest.mock
import requests
#name of the file being tested
import timeofday
class MockResponse:
def __init__(self, text, status_code):
self.text = text
self.status_code = status_code
def json(self):
return json.loads(self.text)
def __iter__(self):
return self
def __next__(self):
return self
#json returned by the API http://worldclockapi.com/api/json/est/now
def mock_requests_timeofday(*args, **kwargs):
text = """
{
"$id": "1",
"currentDateTime": "2019-11-08T15:52-05:00",
"utcOffset": "-05:00:00",
"isDayLightSavingsTime": false,
"dayOfTheWeek": "Friday",
"timeZoneName": "Eastern Standard Time",
"currentFileTime": 132177019635463680,
"ordinalDate": "2019-312",
"serviceResponse": null
}}
"""
response = MockResponse(text, 200)
return response
class TestLocation(unittest.TestCase):
#unittest.mock.patch('requests.get', mock_requests_get_success)
def test_get_time(self):
self.assertEqual(response.status_code, 200)
class TestTimeofday(unittest.TestCase):
#unittest.mock.patch('timeofday.requests.get', mock_requests_timeofday)
def get_time(self):
self.assertEqual(response.status_code, 200)
Your code is currently failing because you directly mock the get function of the module you've imported in your test file.
In order to make your test work, you will have to mock directly the requests.get method of your other file.
This is what a mock of the get method you did in the timeofday.py could look like:
mock.patch('timeofday.requests.get', mock_requests_get_success)
Now when you execute get_time the API call should be mocked and you will receive the answer you defined.
PS: Be aware that the if statement you wrote after the return r.json()["currentDateTime"] will never be executed because your function is ending when you use return.

threaded and asyncio API library

In Python I am trying to create an API for a connected device. I want to be available for both threaded (using request) and async applications (using aiohttp).
What I've come up with is wrapping the get method of both requests and aiohttp in a decorator. This decorator is passed at init and API calls are explicitly wrapped using the passed decorator.
It works, but I'd like to know how others think of this approach ? Are there better ways or will I be running into issues later on ?
Any help appreciated !
def threaded_gett(function):
# The threaded decorator
def wrapper(*args, **kwargs):
url, params = function(*args)
response = requests.get(url, params)
_json = response.json()
return function.__self__.process_response(_json)
return wrapper
def async_gett(function):
# The async decorator
def wrapper(*args, **kwargs):
url, params = function(*args)
try:
resp = yield from function.__self__.session.get(url, params=params)
except Exception as ex:
lgr.exception(ex)
else:
_json = yield from resp.json()
yield from resp.release()
return function.__self__.process_response(_json)
# wrapping the decorator in the async coroutine decorator.
wrapper = asyncio.coroutine(wrapper)
return wrapper
class ThreadedApi(BaseApi):
def __init__(self,threaded_gett):
Base.__init(self,threaded_gett)
class AsyncApi(BaseApi):
def __init__(self,async_gett):
Base.__init(self,async_gett)
class BaseApi():
def __init__(self,get_wrapper):
self.status = get_wrapper(self.status)
def status(self):
return <status path>
Your code is not complete but yes, the approach might work in simple cases (when .process_response() is very generic and could be applied to all API calls).

Python: How to unit test a custom HTTP request Handler?

I have a custom HTTP request handler that can be simplified to something like this:
# Python 3:
from http import server
class MyHandler(server.BaseHTTPRequestHandler):
def do_GET(self):
self.send_response(200)
self.send_header("Content-type", "text/html")
self.end_headers()
# Here's where all the complicated logic is done to generate HTML.
# For clarity here, replace with a simple stand-in:
html = "<html><p>hello world</p></html>"
self.wfile.write(html.encode())
I'd like to unit-test this handler (i.e. make sure that my do_GET executes without an exception) without actually starting a web server. Is there any lightweight way to mock the SimpleHTTPServer so that I can test this code?
Expanding on the answer from jakevdp, I managed to be able to check the output, too:
try:
import unittest2 as unittest
except ImportError:
import unittest
try:
from io import BytesIO as IO
except ImportError:
from StringIO import StringIO as IO
from server import MyHandlerSSL # My BaseHTTPRequestHandler child
class TestableHandler(MyHandlerSSL):
# On Python3, in socketserver.StreamRequestHandler, if this is
# set it will use makefile() to produce the output stream. Otherwise,
# it will use socketserver._SocketWriter, and we won't be able to get
# to the data
wbufsize = 1
def finish(self):
# Do not close self.wfile, so we can read its value
self.wfile.flush()
self.rfile.close()
def date_time_string(self, timestamp=None):
""" Mocked date time string """
return 'DATETIME'
def version_string(self):
""" mock the server id """
return 'BaseHTTP/x.x Python/x.x.x'
class MockSocket(object):
def getsockname(self):
return ('sockname',)
class MockRequest(object):
_sock = MockSocket()
def __init__(self, path):
self._path = path
def makefile(self, *args, **kwargs):
if args[0] == 'rb':
return IO(b"GET %s HTTP/1.0" % self._path)
elif args[0] == 'wb':
return IO(b'')
else:
raise ValueError("Unknown file type to make", args, kwargs)
class HTTPRequestHandlerTestCase(unittest.TestCase):
maxDiff = None
def _test(self, request):
handler = TestableHandler(request, (0, 0), None)
return handler.wfile.getvalue()
def test_unauthenticated(self):
self.assertEqual(
self._test(MockRequest(b'/')),
b"""HTTP/1.0 401 Unauthorized\r
Server: BaseHTTP/x.x Python/x.x.x\r
Date: DATETIME\r
WWW-Authenticate: Basic realm="MyRealm", charset="UTF-8"\r
Content-type: text/html\r
\r
<html><head><title>Authentication Failed</title></html><body><h1>Authentication Failed</h1><p>Authentication Failed. Authorised Personnel Only.</p></body></html>"""
)
def main():
unittest.main()
if __name__ == "__main__":
main()
The code I am testing returns a 401 Unauthorised for "/". Change the response as appopriate for your test case.
Here's one approach I came up with to mock the server. Note that this should be compatible with both Python 2 and python 3. The only issue is that I can't find a way to access the result of the GET request, but at least the test will catch any exceptions it comes across!
try:
# Python 2.x
import BaseHTTPServer as server
from StringIO import StringIO as IO
except ImportError:
# Python 3.x
from http import server
from io import BytesIO as IO
class MyHandler(server.BaseHTTPRequestHandler):
"""Custom handler to be tested"""
def do_GET(self):
# print just to confirm that this method is being called
print("executing do_GET") # just to confirm...
self.send_response(200)
self.send_header("Content-type", "text/html")
self.end_headers()
# Here's where all the complicated logic is done to generate HTML.
# For clarity here, replace with a simple stand-in:
html = "<html><p>hello world</p></html>"
self.wfile.write(html.encode())
def test_handler():
"""Test the custom HTTP request handler by mocking a server"""
class MockRequest(object):
def makefile(self, *args, **kwargs):
return IO(b"GET /")
class MockServer(object):
def __init__(self, ip_port, Handler):
handler = Handler(MockRequest(), ip_port, self)
# The GET request will be sent here
# and any exceptions will be propagated through.
server = MockServer(('0.0.0.0', 8888), MyHandler)
test_handler()
So this is a little tricky depending on how "deep" you want to go into the BaseHTTPRequestHandler behavior to define your unit test. At the most basic level I think you can use this example from the mock library:
>>> from mock import MagicMock
>>> thing = ProductionClass()
>>> thing.method = MagicMock(return_value=3)
>>> thing.method(3, 4, 5, key='value')
3
>>> thing.method.assert_called_with(3, 4, 5, key='value')
So if you know which methods in the BaseHTTPRequestHandler your class is going to call you could mock the results of those methods to be something acceptable. This can of course get pretty complex depending on how many different types of server responses you want to test.

mocking session in requests library

In my python code I have global requests.session instance:
import requests
session = requests.session()
How can I mock it with Mock? Is there any decorator for this kind of operations? I tried following:
session.get = mock.Mock(side_effect=self.side_effects)
but (as expected) this code doesn't return session.get to original state after each test, like #mock.patch decorator do.
Since requests.session() returns an instance of the Session class, it is also possible to use patch.object()
from requests import Session
from unittest.mock import patch
#patch.object(Session, 'get')
def test_foo(mock_get):
mock_get.return_value = 'bar'
Use mock.patch to patch session in your module. Here you go, a complete working example https://gist.github.com/k-bx/5861641
With some inspiration from the previous answer and :
mock-attributes-in-python-mock
I was able to mock a session defined like this:
class MyClient(object):
"""
"""
def __init__(self):
self.session = requests.session()
with that: (the call to get returns a response with a status_code attribute set to 200)
def test_login_session():
with mock.patch('path.to.requests.session') as patched_session:
# instantiate service: Arrange
test_client = MyClient()
type(patched_session().get.return_value).status_code = mock.PropertyMock(return_value=200)
# Act (+assert)
resp = test_client.login_cookie()
# Assert
assert resp is None
I discovered the requests_mock library. It saved me a lot of bother. With pytest...
def test_success(self, requests_mock):
"""They give us a token.
"""
requests_mock.get("https://example.com/api/v1/login",
text=(
'{"result":1001, "errMsg":null,'
f'"token":"TEST_TOKEN",' '"expire":1799}'))
auth_token = the_module_I_am_testing.BearerAuth('test_apikey')
assert auth_token == 'TEST_TOKEN'
The module I am testing has my BearerAuth class which hits an endpoint for a token to start a requests.session with.

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