It's about my understanding of hexagonal architecture, based on the work of Julien Julien Topçu. I don't own the demo. And I haven't tested all the concepts he'd like to demonstrate. Thanks to my pair programming assistants Claude AI, Vercel AI, ChatGPT.
The code could certainly be improved. The main objective was to understand the concepts demonstrated by:
- DDD by Eric Evans
- Port Adapter/Hexagonal Architecture Alistair Cockburn, Juan Manuel Garrido de Paz
You can find original source in kotlin to Hexagonal Architecture.
In the Hive, each bounded-context having domain services are implemented using modules having hexagons. This kind of module have a domain sub-module (hexagon containing the business logic and the ports), and the infrastructure containing the adapters. Modular Monolith developed with the Hive pattern follows a vertical slicing.
To illustrate that, the backend is divided into several modules:
mandalore-express-money
Generic sub-domain containing only value objects. Basically a library without ports and adapters.
mandalore-express-search
Core domain exposing search domain services (features).
mandalore-express-booking
Core domain exposing booking domain services (features).
mandalore-express-annotations
Trick to invert the dependency between the domains and the dependency injection framework (here Spring).
mandalore-express-hypermedia
Technical module which allows controllers of each module to serialize links to external resources.
mandalore-express-composition-root
Composition Root which assembles the application. It builds the context for dependency injection frameworks.
Basically in Spring-based application, this is where you'll find the SpringBootApplication.
maven 3.8.3, Java JDK11.
Build:
cd backend
mvn clean installLaunch:
cd backend/src/mandalore-express-composition-root/
mvn spring-boot:runVisit the repository Hive Repository