Package structure for projects

Package structure for projects

Refer Hexagonal architecture for an introduction to this concept.

Package structure

• domain
  • exception
  • model
  • service
• persistence
  • dto
  • repository
  • entity
• web
  • adapters
    • error
  • controller
  • contract
• consumer
  • listener

Summary of the package structure

• The domain package should have classes that are only responsible for domain logic. This layer is agnostic of web, data stores (PostGres, Redis) or messaging (Kafka).

• The persistence package is responsible for adapting the domain models to data store specific representations and vice-versa. Interactions to other HTTP services via RestTemplate are also done using the Repository pattern. The dto package houses the request and response classes from upstream services.

• The web package is responsible for adapting the domain models to web contract classes and vice-versa. Exceptions raised by the domain layer are transformed by error adapters to web contract specific error responses.

• The listener package houses the Kafka listener.