Book Image

Hands-On Cloud Development with WildFly

By : Tomasz Adamski
Book Image

Hands-On Cloud Development with WildFly

By: Tomasz Adamski

Overview of this book

The book starts by introducing you to WildFly Swarm—a tool that allows you to create runnable microservices from Java EE components. You’ll learn the basics of Swarm operation—creating microservices containing only the parts of enterprise runtime needed in a specific case. Later, you’ll learn how to configure and test those services. In order to deploy our services in the cloud, we’ll use OpenShift. You’ll get to know basic information on its architecture, features, and relationship to Docker and Kubernetes. Later, you’ll learn how to deploy and configure your services to run in the OpenShift cloud. In the last part of the book, you’ll see how to make your application production-ready. You’ll find out how to configure continuous integration for your services using Jenkins, make your application resistant to network failures using Hystrix, and how to secure them using Keycloak. By the end of the book, you’ll have a functional example application and will have practical knowledge of Java EE cloud development that can be used as a reference in your other projects.
Table of Contents (14 chapters)

OpenShift storage concepts

In the previous chapter, we hinted a the volume concept—the tool that is used by OpenShift to implement storage. Let's start by looking at it more thoroughly.


As we mentioned in the preceding chapter, OpenShift's unit of deployment and scaling is a pod, which can contain many containers. The containers in the pod are ephemeral—they can be stopped and started at any moment by Kubernetes. The data stored in the container will be lost when the container goes down because during the restart the fresh container is recreated from the image.

As a result, we will need another tool to implement the storage. Such a tool is the volume.

So, what is a volume? From the technical...