HelloController for Spark, Service & Repository

HelloController.kt

class HelloController(val service: HelloService) {
    init {
        get("/hello") {
            service.sayHello()
        }
    }
}

HelloRepository.kt

interface HelloRepository {
    fun getHello(): String
}

class HelloRepositoryImpl : HelloRepository {
    override fun getHello(): String = "Spark & Koin"
}

HelloService.kt

interface HelloService {
    fun sayHello(): String
}

class HelloServiceImpl(val helloRepository: HelloRepository) : HelloService {
    override fun sayHello() = "Hello ${helloRepository.getHello()} !"
}