Maven Multi-module project to illustrate how to structure a project based on an hexagonal architecture.
| Technology | Purpose |
|---|---|
| Hexagonal architecture | I tried to follow an hexagonal clean architecture when creating this simple example. You can take a look into the project modules to see how the code was divided into application, domain and infrastructure layers. You can also take a look into the interfaces I'm using as "ports" to avoid layer couplings. I think that it could be interesting to understand the difference between the Loan entity at domain level (I will try to complete this example with some DDD concepts), and the LoanEntity at the infrastructure layer. |
| Lombok | Helper to create builders, setters, getters, etc |
| MapStruct | Helper to create mappers to pass objects between the different layers |
| Quarkus | Quarkus is a full-stack, Kubernetes-native Java framework made for Java virtual machines (JVMs) and native compilation, optimizing Java specifically for containers and enabling it to become an effective platform for serverless, cloud, and Kubernetes environments. |
| JUnit 5 | Unit tests creation |
| Mockito | Adds mockito framework for testing purposes |
| Technology | Purpose |
|---|---|
| Hibernate panache | Database access |
| Flyway | To load database at start |
| Technology | Purpose |
|---|---|
| Dynamodb enhanced | Dynamodb enhanced library based on AWS SDK for Java 2.0, compatible with native image and quarkus. |
| Technology | Purpose |
|---|---|
| Resteasy | Annotation based Rest controllers with JSON serialization / desearialization |
| rest-assured | Testing and validating REST services |
| smallrye-openapi | Add OpenAPI spec to the project and helps with the generation of both schema and Swagger UI |
| OpenAPI | The OpenAPI Specification, previously known as the Swagger Specification, is a specification for a machine-readable interface definition language for describing, producing, consuming and visualizing RESTful web services. |
| openapi-generator-maven-plugin | A Maven plugin to support the OpenAPI generator project. |
| Technology | Purpose |
|---|---|
| TBC | TBC |
Compile, test, package and install the different artifacts in your local maven repository.
mvn clean installAfter creating all artifacts you can run the project in dev mode (hotreload enabled + dev services).
mvn quarkus:dev -pl bootloaderBootloader module is the providing the quarkus startup point. If you want to switch the db adapter and use adapter-postgresql, you have to comment the adapter-dynamodb dependency in the pom.xml file and uncomment the adapter-postgresql.
This project is using dev services to provide the external services like DB, Event broker, Identity Manager, etc.
In order to use Dev Services you will generally need a working Docker environment (remote environments are supported). If you don’t have Docker installed you will need to configure your services normally.
You will need to package the bootloader module:
mvn clean package -pl bootloaderIt produces several outputs in ./bootloader/target:
-
getting-started-1.0.0-SNAPSHOT.jar - containing just the classes and resources of the projects, it’s the regular artifact produced by the Maven build - it is not the runnable jar;
-
the quarkus-app directory which contains the quarkus-run.jar jar file - being an executable jar. Be aware that it’s not an
über-jaras the dependencies are copied into subdirectories of quarkus-app/lib/.
You can run the application using: java -jar ./bootloader/target/quarkus-app/quarkus-run.jar
If you want to deploy your application somewhere (typically in a container), you need to deploy the whole quarkus-app directory. Before running the application, don’t forget to stop the hot reload mode (hit CTRL+C), or you will have a port conflict.
For more information about running Quarkus applications (dev, test, prod, native) please take a look at Quarkus - getting started # running-the-application.