In this chapter, we'll put the skills we've learned so far to use by building a microservice using the Kotlin programming language. We also want this microservice to be reactive, and to be as close to real life as possible. For that, we'll use Vert.x framework, the benefits of which we'll list in the next section.

You're probably tired of creating to-do or shopping lists.

So, instead, the microservice will be for a cat shelter. The microservice should be able to do the following:

• Supply an endpoint we can ping to check whether the service is up and running
• List cats currently in the shelter
• Provide us with a means to add new cats

What you'll need to get started:

• JDK 1.8 or later
• IntelliJ IDEA
• Gradle 4.2 or later
• PostgreSQL 9.4 or later

This chapter will assume that you have PostgreSQL already installed and that you have basic knowledge of working with it. If you don't, please refer to the official documentation: https://www.postgresql.org/docs/9.4/static/tutorial-install.html.

In this chapter, we will cover the following topics:

• Getting started with Vert.x
• Handling requests
• Testing
• Working with databases
• EventBus