High cohesion in Microservices - Practice Problems & Coding Challenges

Challenge - 5 Problems

🧠 Conceptual

intermediate

Why is high cohesion important in microservices?

In microservices architecture, why do we aim for high cohesion within each service?

A It allows services to share databases easily, reducing data duplication.

B It makes each service responsible for a single, well-defined task, improving maintainability and scalability.

C It forces all services to depend on each other, increasing integration complexity.

D It reduces the number of services by combining unrelated functionalities.

💡 Hint

Think about how grouping related tasks affects service clarity and updates.

High cohesion means each microservice focuses on a single responsibility. This makes it easier to maintain, test, and scale independently.

❓ Architecture

intermediate

Identifying high cohesion in microservice design

Which of the following microservice designs shows the highest cohesion?

A A service that manages orders and also sends marketing emails.

B A service that handles user authentication, payment processing, and product catalog updates.

C A service dedicated only to managing user profiles and preferences.

D A service that handles inventory updates and customer support tickets.

💡 Hint

Look for the service that groups closely related responsibilities.

Service A focuses solely on user profiles and preferences, which are closely related tasks, showing high cohesion.

❓ scaling

advanced

Impact of high cohesion on microservice scaling

How does high cohesion in microservices affect the ability to scale the system?

A It allows scaling only the entire system together, increasing resource use.

B It prevents scaling because services are too tightly coupled internally.

C It requires scaling all services simultaneously to maintain consistency.

D It enables scaling individual services independently based on their specific load.

💡 Hint

Think about how focused responsibilities affect resource allocation.

High cohesion means each service does one job, so you can scale only the services that need more resources, saving costs.

❓ tradeoff

advanced

Tradeoffs of enforcing very high cohesion in microservices

What is a potential downside of enforcing very high cohesion in microservices?

A It can lead to too many small services, increasing deployment and management overhead.

B It causes services to share too much data, risking data corruption.

C It forces unrelated functionalities into one service, reducing clarity.

D It eliminates the need for service communication, reducing flexibility.

💡 Hint

Consider what happens if you split responsibilities too finely.

Very high cohesion can create many tiny services, which makes deployment, monitoring, and coordination more complex.

❓ component

expert

Designing a highly cohesive microservice for an e-commerce platform

You need to design a microservice for an e-commerce platform that handles product inventory. Which set of responsibilities best ensures high cohesion?

A Managing product stock levels, updating inventory after sales, and handling supplier restock requests.

B Processing customer payments, sending marketing emails, and managing product stock levels.

C Handling supplier restock requests, managing user reviews, and updating product descriptions.

D Managing product stock levels, processing customer payments, and sending order confirmation emails.

💡 Hint

Focus on grouping tasks that relate directly to inventory management.

Option A groups all inventory-related tasks, ensuring the service has a clear, focused responsibility.