Book Image

Learning Spring Boot 2.0 - Second Edition

By : Greg L. Turnquist, Greg L. Turnquist
Book Image

Learning Spring Boot 2.0 - Second Edition

By: Greg L. Turnquist, Greg L. Turnquist

Overview of this book

Spring Boot provides a variety of features that address today's business needs along with today's scalable requirements. In this book, you will learn how to leverage powerful databases and Spring Boot's state-of-the-art WebFlux framework. This practical guide will help you get up and running with all the latest features of Spring Boot, especially the new Reactor-based toolkit. The book starts off by helping you build a simple app, then shows you how to bundle and deploy it to the cloud. From here, we take you through reactive programming, showing you how to interact with controllers and templates and handle data access. Once you're done, you can start writing unit tests, slice tests, embedded container tests, and even autoconfiguration tests. We go into detail about developer tools, AMQP messaging, WebSockets, security, and deployment. You will learn how to secure your application using both routes and method-based rules. By the end of the book, you'll have built a social media platform from which to apply the lessons you have learned to any problem. If you want a good understanding of building scalable applications using the core functionality of Spring Boot, this is the book for you.
Table of Contents (11 chapters)

Unit testing

The smallest scoped tests we can write are referred to as unit tests. In fact, people have been writing tiny tests for years. A common paradigm is to try and test just one class in a given unit test.

To get going, let's test the smallest unit of code we have: our Lombok-enabled Image domain object.

As a reminder, here is what that code looks like:

    public class Image { 
        @Id final private String id; 
        final private String name; 

This tiny little POJO is flagged with Spring Data MongoDB annotations as well as Lombok's @Data annotation providing getters and setters.

A unit test shouldn't be too hard. We can start by creating in /src/test/java, and in the same package as the original class (com.greglturnquist.learningspringboot), as follows:

    public class ImageTests {