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How do I mock a method that uses requests.get with the WITH keyword in my class?

I am having trouble understanding how mocking works when the get responses involve using the with keyword. Here is an example I am following for my class `Album' and I have been successful when I am mocking a url as seen below:
def find_album_by_id(id):
url = f'https://jsonplaceholder.typicode.com/albums/{id}'
response = requests.get(url)
if response.status_code == 200:
return response.json()['title']
else:
return None
Here the test
class TestAlbum(unittest.TestCase):
#patch('album.requests')
def test_find_album_by_id_success(self, mock_requests):
# mock the response
mock_response = MagicMock()
mock_response.status_code = 200
mock_response.json.return_value = {
'userId': 1,
'id': 1,
'title': 'hello',
}
# specify the return value of the get() method
mock_requests.get.return_value = mock_response
# call the find_album_by_id and test if the title is 'hello'
self.assertEqual(find_album_by_id(1), 'hello')
However, I am trying to understand how this would work with the with keyword involved in the code logic which I am using in my project. This is how I changed the method
def find_album_by_id(id):
url = f'https://jsonplaceholder.typicode.com/albums/{id}'
with requests.get(url) as response:
pipelines = response.json()
if response.status_code == 200:
return pipelines['title']
else:
return None
Here is my current test:
#patch('album.requests.get')
def test_find_album_by_id_success(self, mock_requests):
mock_response = MagicMock()
mock_response.status_code = 200
mock_response.pipelines.response.json = {
'userId': 1,
'id': 1,
'title': 'hello',
}
mock_requests.return_value.json.return_value = mock_response
self.assertEqual(find_album_by_id(1), 'hello')
Thanks
I have tried debugging the test and it just never receives the status code of 200 so I am not sure I am mocking response correctly at all? From my understanding the mock_response is supposed to have that status code of 200 but breakline indicates that response is just a MagicMock with nothing in it.

Monkeypatching/mocking the HTTPX external requests

I'm trying to monkeypatch the external request. Here is the code of a web endpoint:
import httpx, json
...
#app.get('/test')
async def view_test(request):
async with httpx.AsyncClient() as client:
# sending external request
api_response = await client.get(
f'https://jsonplaceholder.typicode.com/todos/1',
timeout=10,
)
resp = api_response.json()
# modifying the result
resp['foo'] = 0
# forwarding the modified result back to the user
return HTTPResponse(json.dumps(resp), 200)
When user sends a GET request to /test, it requests an external API (JSONPlaceholder), gets the JSON result and adds 'foo' = 0 to it. After that it forwards the result back to the user.
Here is the Postman result:
{
"userId": 1,
"id": 1,
"title": "delectus aut autem",
"completed": false,
"foo": 0
}
Next, here is my pytest code:
import httpx, pytest
...
# The `client` parameter is the fixture of web app
def test_view_test(client, monkeypatch):
async def return_mock_response(*args, **kwargs):
return httpx.Response(200, content=b'{"response": "response"}')
monkeypatch.setattr(httpx.AsyncClient, 'get', return_mock_response)
_, response = client.test_client.get('/test')
assert response.json == {'response': 'response', 'foo': 0}
assert response.status_code == 200
I used pytest's monkeypatch fixture to mock the HTTPX request's result with {"response": "response"}.
So basically what I expected is that endpoint adds 'foo' = 0 to my mocked result. But instead it returned {"response": "response"} unmodified.
Here's the traceback of pytest -vv command:
> assert response.json == {'response': 'response', 'foo': 0}
E AssertionError: assert {'response': 'response'} == {'response': 'response', 'foo': 0}
E Common items:
E {'response': 'response'}
E Right contains 1 more item:
E {'foo': 0}
E Full diff:
E - {'foo': 0, 'response': 'response'}
E ? ----------
E + {'response': 'response'}
Can someone help me with why the endpoint doesn't modify httpx.AsyncClient().get mocked result?
I used sanic==22.9.0 for backend, httpx==0.23.0 for requests, and pytest==7.2.0 for testing.
Expected to get {'response': 'response', 'foo': 0} instead got {"response": "response"} - an unmodified result of mocked httpx response.

The issue is that sanic-testing uses httpx under the hood. So, when you are monkeypatching httpx you are also impacting the test client. Since you only want to mock the outgoing calls we need to exempt those from being impacted.
My comment to #srbssv on Discord was to monkeypatch httpx with a custom function that would inspect the location of the request. If it was the internal Sanic app, proceed as is. If not, then return with a mock object.
Basically, something like this:
from unittest.mock import AsyncMock
import pytest
from httpx import AsyncClient, Response
from sanic import Sanic, json
#pytest.fixture
def httpx():
orig = AsyncClient.request
mock = AsyncMock()
async def request(self, method, url, **kwargs):
if "127.0.0.1" in url:
return await orig(self, method, url, **kwargs)
return await mock(method, url, **kwargs)
AsyncClient.request = request
yield mock
AsyncClient.request = orig
#pytest.fixture
def app():
app = Sanic("Test")
#app.post("/")
async def handler(_):
async with AsyncClient() as client:
resp = await client.get("https://httpbin.org/get")
return json(resp.json(), status=resp.status_code)
return app
def test_outgoing(app: Sanic, httpx: AsyncMock):
httpx.return_value = Response(201, json={"foo": "bar"})
_, response = app.test_client.post("")
assert response.status == 201
assert response.json == {"foo": "bar"}
httpx.assert_awaited_once()

status_code from pytest is not equal to the real one

Here is a fastapi webapp. I got some trouble in test.
post in crud.py:
async def post(payload: BookSchema):
query = books.insert().values(book=payload.book, author=payload.author,
create_time=payload.create_time, update_time=payload.update_time)
return await database.execute(query=query)
create_book:
#router.post("/book", response_model=BookDB, status_code=201)
async def create_book(payload: BookSchema):
book_id = await crud.post(payload)
response_object = {
"id": book_id,
**payload.dict()
}
return response_object
conftest.py:
import pytest
from starlette.testclient import TestClient
from app.main import app
#pytest.fixture()
def test_app():
with TestClient(app) as client:
yield client
I use pytest to test my case:
def test_create_book_invalid_json(test_app):
response = test_app.post(API_PREFIX + "/book", data=json.dumps({"book": "smart"}))
print(f"response.status_code is {response.status_code}")
assert response.status_code == 422
Expected status_code should be 422 and I got 201. I try to print response.status_code, and the output is 422.
test_books.py::test_create_book_invalid_json FAILED [100%]response.status_code is 422
test_books.py:20 (test_create_book_invalid_json)
201 != 422
Expected :422
Actual :201

You have not provided information about your test client here, but I assume it is a requests-like one. In such case the data parameter expects a dictionary, not a string.
response = test_app.post(url, data={'book': 'smart'})
This will send corresponding form data to your web app. If what you need is sending JSON, use the json parameter instead:
response = test_app.post(url, json={'book': 'smart'})

How to fake my response in pytest requests mock

My function that I am trying to test is returning list of strings:
def listForumsIds:
response = requests.get(url)
forums= response.json().get('forums')
forumsIds= [forum['documentId'] for forum in forums]
# return like: ['id1', 'id2', 'id3'.....]
return forumsIds
My test function:
#requests_mock.mock()
def test_forms(self, m):
# I also used json='response'
m.get('valid url', text="response", status_code=200)
resp = listForumsIds('valid url')
# ERROR !!!!
assert resp == "response"
I am getting error like: json.decoder.JSONDecodeError or str object has no attribute get
How to fake my response to be match return value of my function?

You have to pass the desired payload in the json field of the mocked response. Example, adapted to your code:
class MyTests(unittest.TestCase):
#requests_mock.mock()
def test_forms(self, m):
payload = {"forums": [{"documentId": "id1"}]}
m.register_uri("GET", "https://www.example.com", json=payload)
ids = listForumsIds('https://www.example.com')
assert ids == ['id1']

How can I mock requests and the response?

I am trying to use Pythons mock package to mock Pythons requests module. What are the basic calls to get me working in below scenario?
In my views.py, I have a function that makes variety of requests.get() calls with different response each time
def myview(request):
res1 = requests.get('aurl')
res2 = request.get('burl')
res3 = request.get('curl')
In my test class I want to do something like this but cannot figure out exact method calls
Step 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'
Step 2:
Call my view
Step 3:
verify response contains 'a response', 'b response' , 'c response'
How can I complete Step 1 (mocking the requests module)?

This is how you can do it (you can run this file as-is):
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()
Important Note: If your MyGreatClass class lives in a different package, say my.great.package, you have to mock my.great.package.requests.get instead of just 'request.get'. In that case your test case would look like this:
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()
Enjoy!

Try using the responses library. Here is an example from their documentation:
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"}'
It provides quite a nice convenience over setting up all the mocking yourself.
There's also HTTPretty:
It's not specific to requests library, more powerful in some ways though I found it doesn't lend itself so well to inspecting the requests that it intercepted, which responses does quite easily
There's also httmock.
A new library gaining popularity recently over the venerable requests is httpx, which adds first-class support for async. A mocking library for httpx is: https://github.com/lundberg/respx

Here is what worked for me:
import mock
#mock.patch('requests.get', mock.Mock(side_effect = lambda k:{'aurl': 'a response', 'burl' : 'b response'}.get(k, 'unhandled request %s'%k)))

I used requests-mock for writing tests for separate module:
# module.py
import requests
class A():
def get_response(self, url):
response = requests.get(url)
return response.text
And the tests:
# 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()

this is how you mock requests.post, change it to your http method
#patch.object(requests, 'post')
def your_test_method(self, mockpost):
mockresponse = Mock()
mockpost.return_value = mockresponse
mockresponse.text = 'mock return'
#call your target method now

Here is a solution with requests Response class. It is cleaner IMHO.
import json
from unittest.mock import patch
from requests.models import Response
def mocked_requests_get(*args, **kwargs):
response_content = None
request_url = kwargs.get('url', None)
if request_url == 'aurl':
response_content = json.dumps('a response')
elif request_url == 'burl':
response_content = json.dumps('b response')
elif request_url == 'curl':
response_content = json.dumps('c response')
response = Response()
response.status_code = 200
response._content = str.encode(response_content)
return response
#mock.patch('requests.get', side_effect=mocked_requests_get)
def test_fetch(self, mock_get):
response = requests.get(url='aurl')
assert ...

If you want to mock a fake response, another way to do it is to simply instantiate an instance of the base HttpResponse class, like so:
from django.http.response import HttpResponseBase
self.fake_response = HttpResponseBase()

I started out with Johannes Farhenkrug's answer here and it worked great for me. I needed to mock the requests library because my goal is to isolate my application and not test any 3rd party resources.
Then I read up some more about python's Mock library and I realized that I can replace the MockResponse class, which you might call a 'Test Double' or a 'Fake', with a python Mock class.
The advantage of doing so is access to things like assert_called_with, call_args and so on. No extra libraries are needed. Additional benefits such as 'readability' or 'its more pythonic' are subjective, so they may or may not play a role for you.
Here is my version, updated with using python's Mock instead of a test double:
import json
import requests
from unittest import mock
# defube stubs
AUTH_TOKEN = '{"prop": "value"}'
LIST_OF_WIDGETS = '{"widgets": ["widget1", "widget2"]}'
PURCHASED_WIDGETS = '{"widgets": ["purchased_widget"]}'
# exception class when an unknown URL is mocked
class MockNotSupported(Exception):
pass
# factory method that cranks out the Mocks
def mock_requests_factory(response_stub: str, status_code: int = 200):
return mock.Mock(**{
'json.return_value': json.loads(response_stub),
'text.return_value': response_stub,
'status_code': status_code,
'ok': status_code == 200
})
# side effect mock function
def mock_requests_post(*args, **kwargs):
if args[0].endswith('/api/v1/get_auth_token'):
return mock_requests_factory(AUTH_TOKEN)
elif args[0].endswith('/api/v1/get_widgets'):
return mock_requests_factory(LIST_OF_WIDGETS)
elif args[0].endswith('/api/v1/purchased_widgets'):
return mock_requests_factory(PURCHASED_WIDGETS)
raise MockNotSupported
# patch requests.post and run tests
with mock.patch('requests.post') as requests_post_mock:
requests_post_mock.side_effect = mock_requests_post
response = requests.post('https://myserver/api/v1/get_widgets')
assert response.ok is True
assert response.status_code == 200
assert 'widgets' in response.json()
# now I can also do this
requests_post_mock.assert_called_with('https://myserver/api/v1/get_widgets')
Repl.it links:
https://repl.it/#abkonsta/Using-unittestMock-for-requestspost#main.py
https://repl.it/#abkonsta/Using-test-double-for-requestspost#main.py

This worked for me, although I haven't done much complicated testing yet.
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
Then you can create responses :
mock_response = MockResponse(
headers={'Content-Type' :'application/json'},
status_code=401,
json_={'success': False},
reason='Unauthorized'
)
mock_response.raise_for_status()
gives
requests.exceptions.HTTPError: 401 Client Error: Unauthorized for url: http://example.com

One possible way to work around requests is using the library betamax, it records all requests and after that if you make a request in the same url with the same parameters the betamax will use the recorded request, I have been using it to test web crawler and it save me a lot time.
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/

Can you use requests-mock instead?
Suppose your myview function instead takes a requests.Session object, makes requests with it, and does something to the output:
# 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
You can also use requests_mock with frameworks other than Pytest - the documentation is great.

Using requests_mock is easy to patch any requests
pip install requests-mock
from unittest import TestCase
import requests_mock
from <yourmodule> import <method> (auth)
class TestApi(TestCase):
#requests_mock.Mocker()
def test_01_authentication(self, m):
"""Successful authentication using username password"""
token = 'token'
m.post(f'http://localhost/auth', json= {'token': token})
act_token =auth("user", "pass")
self.assertEqual(act_token, token)

I will add this information since I had a hard time figuring how to mock an async api call.
Here is what I did to mock an async call.
Here is the function I wanted to test
async def get_user_info(headers, payload):
return await httpx.AsyncClient().post(URI, json=payload, headers=headers)
You still need the MockResponse class
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
You add the MockResponseAsync class
class MockResponseAsync:
def __init__(self, json_data, status_code):
self.response = MockResponse(json_data, status_code)
async def getResponse(self):
return self.response
Here is the test. The important thing here is I create the response before since init function can't be async and the call to getResponse is async so it all checked out.
#pytest.mark.asyncio
#patch('httpx.AsyncClient')
async def test_get_user_info_valid(self, mock_post):
"""test_get_user_info_valid"""
# Given
token_bd = "abc"
username = "bob"
payload = {
'USERNAME': username,
'DBNAME': 'TEST'
}
headers = {
'Authorization': 'Bearer ' + token_bd,
'Content-Type': 'application/json'
}
async_response = MockResponseAsync("", 200)
mock_post.return_value.post.return_value = async_response.getResponse()
# When
await api_bd.get_user_info(headers, payload)
# Then
mock_post.return_value.post.assert_called_once_with(
URI, json=payload, headers=headers)
If you have a better way of doing that tell me but I think it's pretty clean like that.

The simplest way so far:
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

For those, who don't want to install additional libs for pytest, there is an example. I will duplicate it here with some extension, based on examples above:
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 ===============================

To avoid installing other dependencies you should create a fake response. This FakeResponse could be a child of Response (I think this is a good approach because it's more realistic) or just a simple class with the attributes you need.
Simple Fake class
class FakeResponse:
status_code = None
def __init__(self, *args, **kwargs):
self.status_code = 500
self.text = ""
Child of Response
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()

Just a helpful hint to those that are still struggling, converting from urllib or urllib2/urllib3 to requests AND trying to mock a response- I was getting a slightly confusing error when implementing my mock:
with requests.get(path, auth=HTTPBasicAuth('user', 'pass'), verify=False) as url:
AttributeError: __enter__
Well, of course, if I knew anything about how with works (I didn't), I'd know it was a vestigial, unnecessary context (from PEP 343). Unnecessary when using the requests library because it does basically the same thing for you under the hood. Just remove the with and use bare requests.get(...) and Bob's your uncle.

For pytest users there is a convinient fixture from https://pypi.org/project/pytest-responsemock/
For example to mock GET to http://some.domain you can:
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'

I will demonstrate how to detach your programming logic from the actual external library by swapping the real request with a fake one that returns the same data. In your view if external api call then this process is best
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

If using pytest:
>>> import pytest
>>> import requests
>>> def test_url(requests_mock):
... requests_mock.get('http://test.com', text='data')
... assert 'data' == requests.get('http://test.com').text
Taken from the official documentation