API client testing in PyTest - Cheat Sheet & Quick Revision

Recall & Review

beginner

What is API client testing?

API client testing checks if the code that talks to an API works correctly. It ensures the client sends requests and handles responses as expected.

beginner

Why do we mock API responses in client testing?

We mock API responses to test the client without calling the real API. This makes tests faster, reliable, and independent of the API server.

intermediate

What pytest feature helps to mock API calls?

The pytest feature called 'monkeypatch' or libraries like 'requests-mock' help replace real API calls with fake responses during tests.

intermediate

How do you check if an API client handles errors correctly?

Write tests that simulate error responses from the API and assert the client reacts properly, like raising exceptions or returning error messages.

intermediate

What is a good practice for API client test assertions?

Assert both the status code and the content of the response. Also, check that the client sends correct request data and headers.

What is the main goal of API client testing?

A To test the API server's performance

B To check the database schema

C To verify the client correctly communicates with the API

D To design the API endpoints

API client testing focuses on the client code that sends requests and processes responses from the API.

Which pytest tool helps replace real API calls with fake ones?

A assert

B fixture

C parametrize

D monkeypatch

monkeypatch allows you to replace parts of your code, like API calls, with mocks during tests.

Why should API client tests mock API responses?

A To increase test execution time

B To avoid network delays and make tests reliable

C To test the real API server

D To skip testing error cases

Mocking avoids real network calls, making tests faster and stable.

What should you assert in API client tests?

A Response status code and content

B Only the response time

C Only the request URL

D The API server logs

Checking both status code and content ensures the client handles responses correctly.

How can you test API client error handling?

A Simulate error responses and check client reactions

B Ignore error cases in tests

C Only test successful responses

D Test the API server instead

Simulating errors helps verify the client handles failures properly.

Explain how you would write a pytest test to check an API client method that fetches user data.

Think about replacing the real API call with a fake response and then verifying the client processes it correctly.

Describe why mocking is important in API client testing and how it improves test quality.

Consider what happens if tests depend on a real API server.