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)

Querying by example

So far, we've built up several reactive queries using property navigation. And we've updated ImageService to reactively transform our queried results into operations needed to support our social media platform.

But something that may not be apparent in the design of our data API is the fact that our method signatures are tied to the properties directly. This means that if a domain field changes, we would have to update the queries, or they will break.

There are other issues we might run into, such as offering the ability to put a filter on our web page, and letting the user fetch a subset of images based on their needs.

What if we had a system that listed information about employees. If we imagined writing a finder that lets a user enter firstName, lastName, and age range, it would probably look like this:

    interface PersonRepository