Integration testing in Rest API - Practice Problems & Coding Challenges

Challenge - 5 Problems

❓ Predict Output

intermediate

What is the output of this integration test response check?

Consider a REST API integration test that sends a GET request to /users/123. The test expects a JSON response with the user's name and status code 200.

What will be the printed output of this test snippet?

Rest API

response = client.get('/users/123')
if response.status_code == 200 and response.json().get('name') == 'Alice':
    print('Test Passed')
else:
    print('Test Failed')

A Test Failed

B Test Passed

C KeyError

D AttributeError

💡 Hint

Check if the response status and JSON content match the expected values.

The test checks if the status code is 200 and the JSON response contains the name 'Alice'. If both are true, it prints 'Test Passed'.

🧠 Conceptual

intermediate

Which component is typically NOT tested in integration testing of REST APIs?

Integration testing usually checks how different parts of a system work together. Which of these is least likely to be tested during REST API integration testing?

A Individual function logic inside a utility module

B API endpoint response format correctness

C Database interaction with API endpoints

D Authentication flow between client and server

💡 Hint

Think about what integration testing focuses on versus unit testing.

Integration testing focuses on how components interact, not on isolated function logic which is covered by unit tests.

🔧 Debug

advanced

Why does this integration test fail with a timeout error?

Given this integration test code snippet that calls an external API endpoint, why does it fail with a timeout error?

Rest API

response = client.get('/external-data', timeout=0.001)
print(response.status_code)

A The timeout value is too low causing the request to abort before response

B The endpoint URL is incorrect causing no response

C The client.get method does not support timeout parameter

D The response object does not have a status_code attribute

💡 Hint

Consider what happens if the timeout is set very low.

The timeout is set to 0.001 seconds, which is too short for the external API to respond, causing a timeout error.

📝 Syntax

advanced

Which option correctly mocks an API response in integration testing?

You want to mock a REST API response in your integration test using Python's unittest.mock. Which code snippet correctly mocks the client.get method to return a response with status code 200 and JSON {'success': true}?

A

with patch('client.get') as mock_get:
    mock_get.return_value = {'status_code': 200, 'json': {'success': True}}

B

with patch('client.get') as mock_get:
    mock_get.status_code = 200
    mock_get.json = {'success': True}

C

with patch('client.get') as mock_get:
    mock_get.return_value.status_code = 200
    mock_get.return_value.json = lambda: {'success': True}

D

with patch('client.get') as mock_get:
    mock_get.return_value.status_code = 200
    mock_get.return_value.json = {'success': True}

💡 Hint

Remember that json is a method, not a property.

Option C correctly sets return_value.status_code and mocks json as a lambda function returning the dictionary.

🚀 Application

expert

What is the number of items in the combined response after integration test aggregation?

An integration test calls two API endpoints: /products returning 3 items and /categories returning 2 items. The test aggregates both JSON lists into one list.

How many items will the combined list contain?

Rest API

products = client.get('/products').json()  # returns list of 3 items
categories = client.get('/categories').json()  # returns list of 2 items
combined = products + categories
print(len(combined))

A 2

B 6

C 3

D 5

💡 Hint

Think about how list concatenation works in Python.

Concatenating two lists of lengths 3 and 2 results in a list of length 5.