basic-spring-boot

A Sample OpenShift Pipeline for a Spring Boot Application

This example demonstrates how to implement a full end-to-end Jenkins Pipeline for a Java application in OpenShift Container Platform. This sample demonstrates the following capabilities:

• Deploying an integrated Jenkins server inside of OpenShift
• Running both custom and oob Jenkins slaves as pods in OpenShift
• "One Click" instantiation of a Jenkins Pipeline using OpenShift's Jenkins Pipeline Strategy feature
• Promotion of an application's container image within an OpenShift Cluster (using oc tag)
• Promotion of an application's container image to a separate OpenShift Cluster (using skopeo) - Coming Soon!
• Automated rollout using the openshift-appler project.

Automated Quickstart

This quickstart can be deployed quickly using Ansible. Here are the steps.

1. Clone this repo and the openshift-applier repo.
2. Log into an OpenShift cluster, then run the following command.

$ oc login
$ ansible-playbook -i ./applier/inventory/ /path/to/openshift-applier/playbooks/openshift-cluster-seed.yml

At this point you should have 3 projects deployed (basic-spring-boot-build, basic-spring-boot-dev, basic-spring-boot-stage, and basic-spring-boot-prod) with our Spring Rest demo application deployed to all 3.

Architecture

The following breaks down the architecture of the pipeline deployed, as well as walks through the manual deployment steps

OpenShift Templates

The components of this pipeline are divided into two templates.

The first template, applier/templates/build.yml is what we are calling the "Build" template. It contains:

• A jenkinsPipelineStrategy BuildConfig
• An s2i BuildConfig
• An ImageStream for the s2i build config to push to

The build template contains a default source code repo for a java application compatible with this pipelines architecture (https://github.com/redhat-cop/spring-rest).

The second template, applier/templates/deployment.yml is the "Deploy" template. It contains:

• A tomcat8 DeploymentConfig
• A Service definition
• A Route

The idea behind the split between the templates is that I can deploy the build template only once (to my dev project) and that the pipeline will promote my image through all of the various stages of my application's lifecycle. The deployment template gets deployed once to each of the stages of the application lifecycle (once per OpenShift project).

Pipeline Script

This project includes a sample Jenkinsfile pipeline script that could be included with a Java project in order to implement a basic CI/CD pipeline for that project, under the following assumptions:

• The project is built with Maven
• The OpenShift projects that represent the Application's lifecycle stages are of the naming format: <app-name>-dev, <app-name>-stage, <app-name>-prod.

This pipeline defaults to use our Spring Boot Demo App.

Bill of Materials

• One or Two OpenShift Container Platform Clusters
  • OpenShift 3.5+ is required
  • Red Hat OpenJDK 1.8 image is required
• Access to GitHub

Manual Deployment Instructions

1. Create Lifecycle Stages

For the purposes of this demo, we are going to create three stages for our application to be promoted through.

• basic-spring-boot-build
• basic-spring-boot-dev
• basic-spring-boot-stage
• basic-spring-boot-prod

In the spirit of Infrastructure as Code we have a YAML file that defines the ProjectRequests for us. This is as an alternative to running oc new-project, but will yeild the same result.

$ oc create -f applier/projects/projects.yml
projectrequest "basic-spring-boot-build" created
projectrequest "basic-spring-boot-dev" created
projectrequest "basic-spring-boot-stage" created
projectrequest "basic-spring-boot-prod" created

2. Stand up Jenkins master in dev

For this step, the OpenShift default template set provides exactly what we need to get jenkins up and running.

$ oc process openshift//jenkins-ephemeral | oc apply -f- -n basic-spring-boot-build
route "jenkins" created
deploymentconfig "jenkins" created
serviceaccount "jenkins" created
rolebinding "jenkins_edit" created
service "jenkins-jnlp" created
service "jenkins" created

4. Instantiate Pipeline

A deploy template is provided at applier/templates/deployment.yml that defines all of the resources required to run our Tomcat application. It includes:

• A Service
• A Route
• An ImageStream
• A DeploymentConfig
• A RoleBinding to allow Jenkins to deploy in each namespace.

This template should be instantiated once in each of the namespaces that our app will be deployed to. For this purpose, we have created a param file to be fed to oc process to customize the template for each environment.

Deploy the deployment template to all three projects.

$ oc process -f applier/templates/deployment.yml --param-file=applier/params/deployment-dev | oc apply -f-
service "spring-rest" created
route "spring-rest" created
imagestream "spring-rest" created
deploymentconfig "spring-rest" created
rolebinding "jenkins_edit" configured
$ oc process -f applier/templates/deployment.yml --param-file=applier/params/deployment-stage | oc apply -f-
service "spring-rest" created
route "spring-rest" created
imagestream "spring-rest" created
deploymentconfig "spring-rest" created
rolebinding "jenkins_edit" created
$ oc process -f applier/templates/deployment.yml --param-file=applier/params/deployment-prod | oc apply -f-
service "spring-rest" created
route "spring-rest" created
imagestream "spring-rest" created
deploymentconfig "spring-rest" created
rolebinding "jenkins_edit" created

A build template is provided at applier/templates/build.yml that defines all the resources required to build our java app. It includes:

• A BuildConfig that defines a JenkinsPipelineStrategy build, which will be used to define out pipeline.
• A BuildConfig that defines a Source build with Binary input. This will build our image.

Deploy the pipeline template in dev only.

$ oc process -f applier/templates/build.yml --param-file applier/params/build-dev | oc apply -f-
buildconfig "spring-rest-pipeline" created
buildconfig "spring-rest" created

At this point you should be able to go to the Web Console and follow the pipeline by clicking in your basic-spring-boot-dev project, and going to Builds -> Pipelines. At several points you will be prompted for input on the pipeline. You can interact with it by clicking on the input required link, which takes you to Jenkins, where you can click the Proceed button. By the time you get through the end of the pipeline you should be able to visit the Route for your app deployed to the myapp-prod project to confirm that your image has been promoted through all stages.

Cleanup

Cleaning up this example is as simple as deleting the projects we created at the beginning.

oc delete project basic-spring-boot-build basic-spring-boot-dev basic-spring-boot-prod basic-spring-boot-stage