{"id":438,"date":"2024-01-29T11:22:01","date_gmt":"2024-01-29T11:22:01","guid":{"rendered":"https:\/\/learnpython.elegantwallp.com\/?p=438"},"modified":"2024-01-29T11:22:02","modified_gmt":"2024-01-29T11:22:02","slug":"python-mock-requests","status":"publish","type":"post","link":"https:\/\/learnpython.elegantwallp.com\/2024\/01\/29\/python-mock-requests\/","title":{"rendered":"Python Mock Requests"},"content":{"rendered":"\n

Summary<\/strong>: In this tutorial, you\u2019ll learn how to mock the\u00a0requests<\/code>\u00a0module in Python to test an API call using the\u00a0unittest\u00a0module.<\/p>\n\n\n\n

The requests<\/code> module is an HTTP library that allows you to send HTTP requests easily. Typically, you use the requests<\/code> module to call an API from a remote server.<\/p>\n\n\n\n

The scenario<\/h2>\n\n\n\n

For the demo purposes, we\u2019ll use a public API provided by\u00a0jsonplaceholder.typicode.com:<\/p>\n\n\n\n

https:\/\/jsonplaceholder.typicode.com\/<\/code>Code language: Python (python)<\/small><\/code><\/pre>\n\n\n\n
To make an API call, you\u2019ll use the\u00a0requests<\/code>\u00a0method to send an HTTP GET method to the following end-point:<\/p>\n\n\n\n
https:\/\/jsonplaceholder.typicode.com\/albums\/1<\/code>Code language: Python (python)<\/small><\/code><\/pre>\n\n\n\n
It\u2019ll return JSON data in the following format:<\/p>\n\n\n\n
{ \"userId\": 1, \"id\": 1, \"title\": \"quidem molestiae enim\" }<\/code>Code language: Python (python)<\/small><\/p>\n\n\n\n
Since the\u00a0requests<\/code>\u00a0module is not a built-in module, you need to install it by running the following pip command:<\/p>\n\n\n\n
pip install requests<\/code>Code language: Python (python)<\/small><\/code><\/pre>\n\n\n\n
Making an API call using the requests module<\/h2>\n\n\n\n
The following defines a new module called\u00a0album.py<\/code>\u00a0with a function\u00a0find_album_by_id()<\/code>\u00a0that returns an album by an id:<\/p>\n\n\n\n
import requests 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<\/code>Code language: Python (python)<\/small><\/code><\/pre>\n\n\n\n
How it works.<\/p>\n\n\n\n
First, format the API end-point that includes the id parameter:<\/p>\n\n\n\n
url = f'https:\/\/jsonplaceholder.typicode.com\/albums\/{id}'<\/code>Code language: Python (python)<\/small><\/code><\/pre>\n\n\n\n
Second, call the\u00a0get()<\/code>\u00a0function of the requests module to get a\u00a0Response<\/code>\u00a0object:<\/p>\n\n\n\n
response = requests.get(url)<\/code>Code language: Python (python)<\/small><\/code><\/pre>\n\n\n\n
Third, call the\u00a0json()<\/code>\u00a0method of the response object if the API call succeeds:<\/p>\n\n\n\n
if response.status_code == 200: return response.json()['title'] else: return None<\/code>Code language: Python (python)<\/small><\/code><\/pre>\n\n\n\n
The response.json()<\/code> returns a dictionary that represents the JSON data.<\/p>\n\n\n\n
Creating a test module<\/h2>\n\n\n\n
We\u2019ll create a\u00a0test_album.py<\/code>\u00a0test module that tests the functions in the\u00a0album.py<\/code>\u00a0module:<\/p>\n\n\n\n
import unittest from album import find_album_by_id class TestAlbum(unittest.TestCase): pass<\/code>Code language: Python (python)<\/small><\/code><\/pre>\n\n\n\n
Mocking the requests module<\/h3>\n\n\n\n
The find_album_by_id()<\/code> function has two dependencies:<\/p>\n\n\n\n
    \n
  • The get()<\/code> method of the requests<\/code> module<\/li>\n\n\n\n
  • The Response<\/code> object returned by the get()<\/code> function.<\/li>\n<\/ul>\n\n\n\n
    So to test the find_album_by_id()<\/code> function, you need to:<\/p>\n\n\n\n
      \n
    • First, mock the requests module and call the get()<\/code> function (mock_requests<\/code>)<\/li>\n\n\n\n
    • Second, mock the returned response object.<\/li>\n<\/ul>\n\n\n\n
      In other words, the mock_requests.get()<\/code> returns a mock response object.<\/p>\n\n\n\n
      To mock the requests module, you can use the patch()<\/code> function. Suppose that the mock_requests<\/code> is a mock of the requests<\/code> module.<\/p>\n\n\n\n
      The mock_requests.get()<\/code> should return a mock for the response. To mock the response, you can use the MagicMock<\/code> class of the unittest.mock<\/code> module.<\/p>\n\n\n\n
      The following shows how to test the\u00a0find_album_by_id()<\/code>\u00a0using the\u00a0test_find_album_by_id_success()<\/code>\u00a0test method:<\/p>\n\n\n\n
      import unittest from unittest.mock import MagicMock, patch from album import find_album_by_id class TestAlbum(unittest.TestCase): @patch('album.requests') def test_find_album_by_id_success(self, mock_requests): # mock the response<\/em> 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<\/em> mock_requests.get.return_value = mock_response # call the find_album_by_id and test if the title is 'hello'<\/em> self.assertEqual(find_album_by_id(1), 'hello')<\/code>Code language: Python (python)<\/small><\/code><\/pre>\n\n\n\n
      How it works.<\/p>\n\n\n\n
      First, patch the\u00a0requests<\/code>\u00a0module as the\u00a0mock_requests<\/code>\u00a0object:<\/p>\n\n\n\n
      @patch('album.requests') def test_find_album_by_id_success(self, mock_requests): # ...<\/em><\/code>Code language: Python (python)<\/small><\/code><\/pre>\n\n\n\n
      Second, mock the response of the\u00a0get()<\/code>\u00a0function using the\u00a0MagicMock<\/code>\u00a0class. In this test method, we specify the status code 200 and\u00a0return_value<\/code>\u00a0of the\u00a0json()<\/code>\u00a0function as a hard-coded value:<\/p>\n\n\n\n
      mock_response = MagicMock() mock_response.status_code = 200 mock_response.json.return_value = { 'userId': 1, 'id': 1, 'title': 'hello', }<\/code>Code language: Python (python)<\/small><\/code><\/pre>\n\n\n\n
      Third, use the mock_response as the return value of the\u00a0get()<\/code>\u00a0function:<\/p>\n\n\n\n
       mock_requests.get.return_value = mock_response<\/code>Code language: Python (python)<\/small><\/code><\/pre>\n\n\n\n
      Finally, test if the title of the album is equal to the one that we specified in the\u00a0return_value<\/code>\u00a0of the\u00a0mock_response<\/code>:<\/p>\n\n\n\n
      self.assertEqual(find_album_by_id(1), 'hello')<\/code>Code language: Python (python)<\/small><\/code><\/pre>\n\n\n\n
      Run the test:<\/p>\n\n\n\n
      python -m unittest -v<\/code>Code language: Python (python)<\/small><\/code><\/pre>\n\n\n\n
      Output:<\/p>\n\n\n\n
      test_find_album_by_id_success (test_album.TestAlbum) ... ok ---------------------------------------------------------------------- Ran 1 test in 0.001s OK<\/code>Code language: Python (python)<\/small><\/code><\/pre>\n\n\n\n
      By using the same technique, you can also test the\u00a0find_album_by_id()<\/code>\u00a0function in the failed case:<\/p>\n\n\n\n
      import unittest from unittest.mock import MagicMock, patch from album import find_album_by_id class TestAlbum(unittest.TestCase): @patch('album.requests') def test_find_album_by_id_success(self, mock_requests): # mock the response<\/em> 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<\/em> mock_requests.get.return_value = mock_response # call the find_album_by_id and test if the title is 'hello'<\/em> self.assertEqual(find_album_by_id(1), 'hello') @patch('album.requests') def test_find_album_by_id_fail(self, mock_requests): mock_response = MagicMock() mock_response.status_code = 400 mock_requests.get.return_value = mock_response self.assertIsNone(find_album_by_id(1))<\/code>Code language: Python (python)<\/small><\/code><\/pre>\n\n\n\n
      Output:<\/p>\n\n\n\n
      test_find_album_by_id_fail (test_album.TestAlbum) ... ok test_find_album_by_id_success (test_album.TestAlbum) ... ok ---------------------------------------------------------------------- Ran 2 tests in 0.002s OK<\/code><\/code><\/pre>\n","protected":false},"excerpt":{"rendered":"
      Summary: In this tutorial, you\u2019ll learn how to mock the\u00a0requests\u00a0module in Python to test an API call using the\u00a0unittest\u00a0module. The requests module is an HTTP library that allows you to send HTTP requests easily. Typically, you use the requests module to call an API from a remote server. The scenario For the demo purposes, we\u2019ll use a public API […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[43],"tags":[],"class_list":["post-438","post","type-post","status-publish","format-standard","hentry","category-3-python-unit-testing"],"_links":{"self":[{"href":"https:\/\/learnpython.elegantwallp.com\/wp-json\/wp\/v2\/posts\/438","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/learnpython.elegantwallp.com\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/learnpython.elegantwallp.com\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/learnpython.elegantwallp.com\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/learnpython.elegantwallp.com\/wp-json\/wp\/v2\/comments?post=438"}],"version-history":[{"count":1,"href":"https:\/\/learnpython.elegantwallp.com\/wp-json\/wp\/v2\/posts\/438\/revisions"}],"predecessor-version":[{"id":439,"href":"https:\/\/learnpython.elegantwallp.com\/wp-json\/wp\/v2\/posts\/438\/revisions\/439"}],"wp:attachment":[{"href":"https:\/\/learnpython.elegantwallp.com\/wp-json\/wp\/v2\/media?parent=438"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/learnpython.elegantwallp.com\/wp-json\/wp\/v2\/categories?post=438"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/learnpython.elegantwallp.com\/wp-json\/wp\/v2\/tags?post=438"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}