Request and response validation in Testing Fundamentals - Practice Problems & Coding Challenges

Challenge - 5 Problems

❓ Predict Output

intermediate

What is the output of this API response validation code?

Consider this Python code snippet that validates an API JSON response status and content:

response = {'status_code': 200, 'data': {'user': 'alice', 'id': 123}}

assert response['status_code'] == 200
assert 'user' in response['data']
print('Validation passed')

What will be printed when this code runs?

Testing Fundamentals

response = {'status_code': 200, 'data': {'user': 'alice', 'id': 123}}

assert response['status_code'] == 200
assert 'user' in response['data']
print('Validation passed')

A KeyError

B AssertionError

C TypeError

D Validation passed

💡 Hint

Check if the status code is 200 and if the key 'user' exists in the nested data dictionary.

The response has status_code 200 and the 'user' key is present in the 'data' dictionary, so both assertions pass and 'Validation passed' is printed.

❓ assertion

intermediate

Which assertion correctly checks the response contains a non-empty 'items' list?

You receive this JSON response from an API:

{'status': 'success', 'items': [1, 2, 3]}

Which assertion statement correctly verifies that 'items' exists and is not empty?

A assert response['items'] != None

B assert 'items' in response and len(response['items']) > 0

C assert response['items'] is not []

D assert response['items']

💡 Hint

Check both the presence of the key and that the list has elements.

Option B explicitly checks the key exists and the list length is greater than zero, ensuring 'items' is present and non-empty.

Option B only checks not None but key might be missing.

Option B compares list identity which is unreliable.

Option B passes if list is truthy but fails if key missing.

🔧 Debug

advanced

Why does this request validation test fail with a KeyError?

Given this test code snippet:

request = {'method': 'POST', 'body': {'username': 'bob'}}
assert request['body']['password'] == 'secret'

Why does this test raise a KeyError?

Testing Fundamentals

request = {'method': 'POST', 'body': {'username': 'bob'}}
assert request['body']['password'] == 'secret'

A The 'password' key does not exist in the 'body' dictionary, causing KeyError

B The 'body' key is missing in the request dictionary

C The 'method' key is not 'POST', causing assertion failure

D The 'password' value is None, causing TypeError

💡 Hint

Check if the key you access exists in the dictionary.

The 'body' dictionary has only 'username' key. Accessing 'password' key raises KeyError because it is missing.

🧠 Conceptual

advanced

What is the main purpose of response schema validation in API testing?

Why do testers perform response schema validation when testing APIs?

A To ensure the response structure and data types match the expected format

B To check if the API server is running and reachable

C To verify the response time is under a threshold

D To confirm the API request headers are correctly set

💡 Hint

Think about what schema means in data context.

Response schema validation checks that the response JSON has the correct keys, nested structure, and data types as expected.

❓ framework

expert

Which test framework feature best supports automated request and response validation?

In automated API testing, which feature of a test framework helps validate both request payloads and response data effectively?

A Static code analysis tools for syntax checking

B Manual test case execution with screenshots

C Data-driven testing with parameterized test cases

D Version control integration for code commits

💡 Hint

Consider how to run the same test with many input and output variations automatically.

Data-driven testing allows running the same test logic with multiple sets of request and expected response data, automating validation efficiently.