Microservices

Microservices

References:

• Building Microservices, Sam Newman.
• Monolith to Microservice, Sam Newman.

What are Microservices?
Microservices are small, autonomous services that work together.

Microservices Characteristics

• Small, focused on doing one thing well:
  • Single Responsibility Principle.
  • Services boundaries on business boundaries.
• Autonomous
  • Our microservice is a separate entity. It might be deployed as an isolated service or in its own operating system process.
  • Avoid multiple services onto the same machine.

Key Benefits

• Technology Heterogeneity.
• Resilience:
  • Isolate a failing component that doesn’t cascade.
• Scaling:
  • Scale just the services that need to be scaled.
• Ease of deployment:
  • We can make a change to ca single service and deploy it independently of the rest of the system.
• Organizational alignment:
  • Microservices allows us to align our architecture to our organization.
• Composability (reuse of functionality).
• Optimizing for replaceability:
  • we can rewrite services when required.

Modeling Microservices

Loose Coupling
A change to one service should not require a change to another.

High Cohesion Ensure that related behaviour is in one place, and that communicate with other boundaries as loosely as possible.

Integrating Microservices

• principles-for-integration
• integration-patterns

Forms of Integration:

• The shared Database.
• Sync vs Async.

Testing, deployment, etc etc.