Hands-On Microservices with Kotlin

Creating a service interface

First, we will create a service interface. We could do this in IntelliJ by right-clicking in our package and selecting a new Kotlin File | Class and then choosing Interface in the drop-down. We will be naming it CustomerService.

We will define the methods that our service will need:

package com.microservices.chapter3interface CustomerService {  fun getCustomer(id: Int) : Customer?  fun createCustomer(customer: Customer)  fun deleteCustomer(id: Int)  fun updateCustomer(id: Int, customer: Customer)  fun searchCustomers(nameFilter: String): List<Customer>}

These operations don't expose how customers are stored/saved or searched, they are purely the interface that we like to have and are not exposing anything internal ...