Demo for Server Side Software Developers South NL meetup 'Back-end programming: making your applications cloud ready'

Meetup event: https://www.meetup.com/Server-Side-Software-Developers-South-NL/events/264919153/

Pre-requisuites

• Docker for Desktop with Kubernetes enabled
• WSL (When running on Windows)

Before continuing, test that connectivity to Kubernetes is working

# docker-for-desktop test
kubectl --context=docker-for-desktop cluster-info

# all Jenkins demo deployments will be done to the default docker cluster. To check the default settings:
kubectl config current-context

Jenkins setup

Before starting docker-compose, make sure you have created the following files

• docker hub credentials for pushing images
  • .secrets/docker-hub-username
  • .secrets/docker-hub-password
• github credentials for discoverying repositories
  • .secrets/github-username
  • .secrets/github-password
• .env file

  SMEE_CHANNEL=<channel id>
  HOME=<only needed on Windows, set to C:\Users\username>

The following files will be automatically created on first start, these are:

• ./secrets/kubectl-encoded-config (a copy of ~/.kube/config)
• ./secrets/ssh-github-java-meetup-key (generated ssh keypair)
• ./secrets/ssh-github-java-meetup-key.pub (generated ssh keypair, used for cloning repositories)

Start jenkins using docker-compose

docker-compose --compatibility up -V --build

After Jenkins is up and running you can go ahead and visit these URL's

• Jenkins URL: http://localhost:8080
• Jenkins configuration as code: http://localhost:8080/configuration-as-code
• Jenkins Job DSL reference: http://localhost:8080/plugin/job-dsl/api-viewer/index.html

Kubernetes setup (Docker for Desktop)

Provision kubernetes with some default demo deployments. After running the script the following is done

• kubernetes-dashboard installed
• k8dash installed (another kubernetes dashboard)
• namespace 'java-meetup' created

# This installs some kubernetes tools using 'kubectl --context=docker-for-desktop'
./setup.sh

If something doesn't work in Docker for Desktop, try the following

# Check for any errors in the docker log
tail -f /c/Users/<username>/AppData/Local/Docker/log.txt

# If Kubernetes fails to start, remove all docker-for-desktop certificates.
# These are automatically re-generated after a first restart
rm -rf /c/ProgramData/DockerDesktop/pki

References

• Jenkins Job DSL docs: https://jenkinsci.github.io/job-dsl-plugin

Demo

Prepare:

• kubectl delete ns java-meetup && kubectl create ns java-meetup

Demo 1 - Maven build using Jenkins & Docker

• http://localhost:8080 (show jobs)
• vscode: Jenkinsfile-1-build
• http://localhost:8080/blue/organizations/jenkins/java-meetup-1-build

Demo 2 - Docker build and push

• http://localhost:8080 (show jobs)
• vscode: Jenkinsfile-2-docker-image-build
• http://localhost:8080/blue/organizations/jenkins/java-meetup-2-docker-image-build
• https://cloud.docker.com/u/jwnmulder/repository/docker/jwnmulder/java-meetup-quarkus

Demo 3 - Kubernetes deployment

• vscode: kustomize files
• vscode: Jenkinsfile-3-kubernetes-deploy
• vscode: > kubectl get events -n java-meetup --watch
• http://localhost:8080/blue/organizations/jenkins/java-meetup-3-kubernetes-deploy

Demo 4 - Testing on Kubernetes - multi branch pipeline

• vscode: Jenkinsfile
• http://kubernetes.docker.internal:31523 (check ./setup.sh for actual URL)
• test multibranch pipeline webhook

  git checkout master
  git branch -d feature/1 feature/2 feature/3
  git push origin --delete feature/1 feature/2 feature/3
  git checkout -b feature/1
  git checkout -b feature/2
  git checkout -b feature/3
  git checkout master
  git push --all origin
  kubectl get events -n java-meetup --watch