Request and response validation in Testing Fundamentals - Test Execution Trace

Test Overview

This test sends a request to a web API and checks if the response status and data are correct. It verifies that the server returns the expected success code and the right message in the response body.

Test Code - unittest

Testing Fundamentals

import requests
import unittest

class TestAPIRequestResponse(unittest.TestCase):
    def test_get_user(self):
        url = "https://api.example.com/user/123"
        response = requests.get(url)
        self.assertEqual(response.status_code, 200)
        data = response.json()
        self.assertIn('username', data)
        self.assertEqual(data['username'], 'john_doe')

if __name__ == '__main__':
    unittest.main()

Execution Trace - 6 Steps

Step	Action	System State	Assertion	Result
1	Test starts	Test runner initialized, ready to execute test_get_user	-	PASS
2	Sends GET request to https://api.example.com/user/123	HTTP request sent, waiting for response	-	PASS
3	Receives HTTP response with status code 200	Response received with JSON body {"username": "john_doe", "id": 123}	Check response.status_code == 200	PASS
4	Parses JSON response body	Parsed data contains keys: username, id	Check 'username' key exists in response JSON	PASS
5	Verifies username value is 'john_doe'	username value is 'john_doe'	Check data['username'] == 'john_doe'	PASS
6	Test ends successfully	All assertions passed, test case completed	-	PASS

Failure Scenario

Failing Condition: Response status code is not 200 or username key missing or username value incorrect

Execution Trace Quiz - 3 Questions

What does the test check first after sending the request?

A The HTTP status code is 200

B The username value is 'john_doe'

C The response time is less than 1 second

D The response contains an error message

Key Result

Always validate both the HTTP status code and the response data to ensure the API behaves as expected and returns correct information.