Hexagonal Architecture With Spring Boot

Hexagonal architecture example

WIP project that aims to have a basic structure of hexagonal infrastructure setup with spring boot example...

• Ports: Interfaces in core (domain)
• Adapters: Implementations of ports
• API: that which drives the core (web api for example)
• SPI (Service provider interface): that which is driven by core (database for example)

Example

• Core defines interfaces (ports) for the input (API) and for the output (SPI)

Input adapters (API)

• Web input adapter implements one of the ports and exposes a web api that drives the core
• Different input adapters can drive the logic, for example pubsub subscription etc...

Output adapters (SPI)

• Firebase output adapter implements one of the ports and provides means for persisting the data (in firebase)
• Different output adapters can implement output port, for example Postgres adapter to store data into the database...

Config

If you are using a firebase project: https://firebase.google.com/docs/admin/setup

export GOOGLE_APPLICATION_CREDENTIALS="/home/user/Downloads/service-account-file.json"

Or you can have a dummy adapter that stores data into h2 for example...

Update the application-dev.properties file with following:

firebase.sa=/path/to/serviceaccount/key/firebaseSA.json
firebase.db=https://your-db.firebasedatabase.app

Run the project

  $ ./mvnw spring-boot: run (or mvn spring-boot:run)