Spring Boot REST API Projects With Code Examples

This guide will help you understand the REST API projects with code examples on GitHub. We have a number of articles explaining these projects. These code examples will help beginners and experts to learn and gain expertise in developing RESTful Services with Spring Boot.

Spring Boot REST API Projects - Code Examples on GitHub

Let’s look at the articles in the following sections

• Projects Creating Basic REST API
• Adding Unit and Integration Tests to RESTful Services
• Securing RESTful Services
• Basic RESTful Service Features
• Advanced RESTful Service Features

Projects Creating Basic REST API

We explore a couple of options to create RESTful Services with Spring Boot:

• Using Spring Boot Web Starter
• Using Spring Data REST Starter

Using Spring Boot Web Starter, we have articles with

• An article focusing on basics of a REST Service
• A project exposing an end to end CRUD API for an entire Resource. The project uses JPA (Hibernate) to connect to an H2 in-memory database.

Adding Unit and Integration Tests to RESTful Services

Automation Tests (including Unit and Integration Tests) are a key part of ensuring your services and APIs evolve over a time period.

Let’s consider a StudentController which depends on StudentService.

In the unit test

• We will mock out the StudentService using Mockito
• We will use Mock MVC framework to launch only StudentController.

A key part of unit testing is to restrict the scope to a minimum. In this unit test, we want to test only the methods in StudentController.

In the integration test:

• We will launch the complete Spring Boot application using @SpringBootTest
• We will invoke the service methods using TestRestTemplate
• We will assert the results using a great JSON assert framework - org.skyscreamer.jsonassert.JSONAssert

A key part of integration testing is testing all the layers in the application.

Securing RESTful Services

In the article below, we implement basic security for a REST API.

Basic Restful Service Features

Great REST APIs have:

• Awesome Exception Handling - You would want to return the right response with the exact response status based on the situation.
• Proper Validation - You would want to validate the right stuff and return a message which helps the consumer understand what failed.
• Current Documentation - A consumer needs to understand how to use your API. Great documentation makes your consumer and your job easy.

The articles below explore these features in depth.

REST API Advanced Features

At the next level, REST APIs have:

• HATEOAS - HATEOAS stands for “Hypermedia as the engine of application state.” When some details of a resource are requested, you will provide the resource details as well as details of related resources and the possible actions you can perform on the resource. For example, when requesting information about a Facebook user, a REST service can return the following:
  • User details.
  • Links to get their recent posts.
  • Links to get their recent comments.
  • Links to retrieve their friend’s list.
• Content Negotiation - Why should JSON be the only data exchange format to be supported? What if your consumer loves (or is stuck with) XML? Content Negotiation helps you support multiple data exchange formats for your RESTful API.
• Versioning - As your API evolves with your and your consumer needs, you would have the need to have multiple versions of the same Resouce API. How do you handle that?

The articles below explore these features in depth.

Other References

• Other great courses at in28Minutes
• Spring - spring-framework-tutorial-for-beginners
• Spring MVC - https://www.youtube.com/watch?v=BjNhGaZDr0Y
• Spring Boot - https://www.youtube.com/watch?v=PSP1-2cN7vM
• Eclipse - https://www.youtube.com/watch?v=s4ShbtOHMCA
• Maven - https://www.youtube.com/watch?v=0CFWeVgzsqY
• JUnit - https://www.youtube.com/watch?v=o5k9NOR9lrI
• Mockito - https://www.youtube.com/watch?v=d2KwvXQgQx4