API client testing in PyTest - Test Execution Trace

Test Overview

This test checks if the API client correctly fetches user data from a web service and verifies the response content.

Test Code - pytest

PyTest

import requests
import pytest

def get_user(user_id):
    response = requests.get(f"https://jsonplaceholder.typicode.com/users/{user_id}")
    response.raise_for_status()
    return response.json()


def test_get_user():
    user = get_user(1)
    assert user["id"] == 1
    assert user["username"] == "Bret"
    assert "email" in user

Execution Trace - 7 Steps

Step	Action	System State	Assertion	Result
1	Test starts	pytest test runner initialized	-	PASS
2	Calls get_user(1) which sends GET request to https://jsonplaceholder.typicode.com/users/1	HTTP request sent to API server	-	PASS
3	Receives HTTP 200 OK response with JSON user data	Response JSON: {"id":1,"username":"Bret","email":"[e-mail]", ...}	-	PASS
4	Asserts user["id"] == 1	User data loaded in memory	Check if user id equals 1	PASS
5	Asserts user["username"] == "Bret"	User data loaded in memory	Check if username is 'Bret'	PASS
6	Asserts "email" key exists in user data	User data loaded in memory	Check if 'email' field is present	PASS
7	Test ends successfully	All assertions passed	-	PASS

Failure Scenario

Failing Condition: API returns 404 Not Found or user data is missing expected fields

Execution Trace Quiz - 3 Questions

What does the test verify about the API response?

A The user id is 1 and username is 'Bret'

B The API returns a 500 server error

C The user has no email field

D The API response is empty

Key Result

Always verify both the HTTP status and the content of the API response to ensure the client handles data correctly.