API API Mocking and Stubbing 3

Question 1

What is 'contract testing' in API testing?

Accepted Answer

Verifying that an API provider and its consumers agree on the expected structure and behavior of the API interface

Answer

Verifying that API usage agreements between companies are legally enforceable

Answer

Running tests against endpoints explicitly listed in the API service contract document

Answer

Automatically generating service level agreements from API test result data

Question 2

Which tool is specifically designed for consumer-driven contract testing of APIs?

Accepted Answer

Pact

Answer

Postman

Answer

WireMock

Answer

Mockito

Question 3

What is the primary risk of using overly simplified API mocks in automated tests?

Accepted Answer

Tests may pass against the mock but fail in production if the mock does not accurately reflect real API behavior

Answer

Simplified mocks will cause test suites to run significantly slower than necessary

Answer

Simplified mocks consume substantially more memory than complex, fully-featured mocks

Answer

Simple mocks cannot be integrated into modern CI/CD pipeline toolchains

Question 4

In API mocking, what does 'chaos engineering' applied to mock servers involve?

Accepted Answer

Deliberately configuring mocks to return errors, timeouts, or malformed responses to verify system resilience

Answer

Using randomly generated test data payloads to stress-test API parsers

Answer

Running API test cases in random order to uncover hidden ordering dependencies

Answer

Generating intentionally invalid API schemas to test schema validator robustness

Question 5

When should you prefer integration testing against real APIs over mock-based testing?

Accepted Answer

During final acceptance testing when verifying actual compatibility with the real third-party service is critical

Answer

Whenever you want faster test feedback cycles in the local development environment

Answer

When network connectivity to the real API is slow or unreliable during development

Answer

When the development environment has insufficient resources to maintain real API connections

Question 6

What is 'stateful mocking' in API testing?

Accepted Answer

Configuring a mock server to change its responses based on the sequence or history of previous requests received

Answer

Mocking APIs that use stateful HTTP session management protocols like cookies

Answer

Using statically defined, unchanging responses for all requests to a mock endpoint

Answer

Mocking APIs that maintain persistent WebSocket connections with clients

Question 7

According to the 'test pyramid' principle, how should API mock usage be distributed across testing levels?

Accepted Answer

Use mocks extensively in fast unit tests to isolate components, less so in integration tests, and minimally in end-to-end tests

Answer

Use mocks only at the UI/end-to-end testing level to maximize realistic coverage

Answer

Avoid all mocking at every level because it reduces test suite reliability and confidence

Answer

Apply mocks equally at unit, integration, and end-to-end levels to ensure testing consistency