Defining environment variables within a manifest file is really useful, as it allows you to abstract configuration values away from the application you’re building. Similarly to Docker Swarm, you can define environment variables for your Kubernetes Pods and Deployments within those manifest files. In Kubernetes, everything is a resource, and you manage those resources through manifest files. You can define environment variables in the stacks files which are then passed to the running containers. In Docker Swarm, you deploy services via a stack file, this is very similar to docker-compose for those familiar with that approach.
One of those challenges was how to externalize the Spring Boot configuration within the Kubernetes cluster, I’d thought it would be similar to Docker Swarm, but there were several differences I found along the way.
My previous experience has primarily been with Docker Swarm up until this project, so it’s been an interesting switch with different challenges. I’ve recently been working on a project where we’re writing Spring Boot microservices, which are being deployed into a Kubernetes cluster. Kubernetes is an open source container management and orchestration system, which makes it quick and easy to deploy and manage those production grade applications. Spring Boot is a widely used JVM-based framework which allows you to build out stand-alone, production grade applications. Spring Boot and Kubernetes go hand in hand when building modern microservices. =jdbc:mysql://$" -t "$DOCKER_USERNAME"/semaphore-demo-java-spring:$SEMAPHORE_WORKFLOW_ID.
Then, between the … tags, add the MySQL driver as a dependency: įinally create a production-only properties file at src/main/resources/application-production.properties: .dialect=55Dialect You can follow me with MySQL on this section or choose any other backend from the Hibernate providers page.įirst, edit the Maven manifest file (pom.xml) to add a production profile inside the … tags:
For the purposes of this tutorial, I’ll choose a MySQL. Fortunately, this is easily fixed by adding a new profile with a real database. You may recall from the first part of the tutorial that our application has a glaring flaw: the lack of data persistence-our precious data is lost across reboots. With Kubernetes, we can run those packages in the cloud, scaling them up and down to go along with fluctuating demands, and releasing updates with no downtime.
We’ll extend CI/CD with Continuous Deployment to a Kubernetes cluster.ĭocker allows us to create easy-to-deploy, portable packages for our application.
In this second (and final) part, we’ll introduce Kubernetes to the picture. We used CI/CD to build and test a Java Spring microservice application, and the end result was a ready-to-deploy Docker image. In part one of this tutorial, we learned about the basics of Docker and Continuous Integration and Delivery (CI/CD).