Microservices for Java Developers

Chapter 6. Hands-on Cluster Management, Failover, and Load Balancing

In Chapter 5, we just had a quick introduction to cluster management, Linux containers, and cluster management. Let’s jump into using these things to solve issues with running microservices at scale. For reference, we’ll be using the microservice projects we developed in Chapters 2, 3, and 4 (Spring Boot, Dropwizard, and WildFly Swarm, respectively). The following steps can be accomplished with any of the three Java frameworks.

Getting Started

To package our microservice as a Docker image and eventually deploy it to Kubernetes, let’s navigate to our project (Spring Boot example in this case) and return to JBoss Forge. JBoss Forge has some plug-ins for making it easy to quickly add the Maven plug-ins we need to use:

$ cd hola-springboot
$ forge

Now let’s install a JBoss Forge addon:

hola-springboot]$ addon-install \
--coordinate io.fabric8.forge:devops,2.2.148

***SUCCESS*** Addon io.fabric8.forge:devops,2.2.148 was
installed successfully.

Now let’s add the Maven plug-ins:

[hola-springboot]$ fabric8-setup
***SUCCESS*** Added Fabric8 Maven support with base Docker
image: fabric8/java-jboss-openjdk8-jdk:1.0.10. Added the
following Maven profiles [f8-build, f8-deploy,
f8-local-deploy] to make building the project easier,
e.g., mvn -Pf8-local-deploy

Let’s take a look at what the tooling did. If we open the pom.xml file, we see it added some properties:

<docker.assemblyDescriptorRef>
    artifact
</docker.assemblyDescriptorRef> ...