Automated testing strategy in Microservices - Practice Problems & Coding Challenges

Challenge - 5 Problems

🧠 Conceptual

intermediate

Key benefit of contract testing in microservices

Which of the following best describes the main benefit of using contract testing between microservices?

A It automatically scales microservices based on traffic.

B It ensures that the user interface looks consistent across services.

C It verifies that the communication between services adheres to agreed API specifications.

D It replaces the need for unit testing within each microservice.

💡 Hint

Think about how microservices communicate and what contract testing checks.

Contract testing verifies that the API requests and responses between microservices match the agreed contract, preventing integration issues.

❓ Architecture

intermediate

Designing an automated testing pipeline for microservices

Which sequence best represents a scalable automated testing pipeline for microservices from code commit to deployment?

A 1,2,4,3

B 1,3,2,4

C 2,1,3,4

D 1,2,3,4

💡 Hint

Think about testing from smallest scope to largest before deployment.

Unit tests run first to check code correctness, then contract tests verify API compatibility, followed by deployment to staging and end-to-end tests.

❓ scaling

advanced

Scaling automated tests for a large microservices system

What is the best approach to scale automated testing when the number of microservices grows to hundreds?

A Use parallel test execution with isolated environments per microservice.

B Skip integration tests to save time and run only unit tests.

C Only run tests for the microservice with the most recent code changes.

D Run all tests for all microservices sequentially on a single server.

💡 Hint

Consider how to reduce test time and avoid interference between tests.

Parallel execution with isolated environments allows tests to run faster and independently, supporting scalability.

❓ tradeoff

advanced

Tradeoff between test coverage and deployment speed

In a continuous deployment pipeline for microservices, what is a common tradeoff when increasing automated test coverage?

A Increasing test coverage can slow down deployment speed due to longer test execution.

B More tests reduce the need for monitoring in production.

C Higher test coverage always leads to faster deployments.

D Test coverage does not affect deployment speed.

💡 Hint

Think about how running more tests affects pipeline duration.

More tests mean longer execution times, which can delay deployments despite improving reliability.

❓ estimation

expert

Estimating test infrastructure capacity for microservices

You have 50 microservices, each with 100 automated tests averaging 5 seconds per test. If you want to run all tests daily within 1 hour, how many parallel test runners are needed?

A 5

B 10

C 50

D 100

💡 Hint

Calculate total test time and divide by allowed time to find parallelism.

Total tests = 50 * 100 = 5000 tests. Total time = 5000 * 5s = 25000s. 1 hour = 3600s. Parallel runners = 25000 / 3600 ≈ 7, so 10 runners cover comfortably.