This document discusses using Helm and continuous delivery to deploy applications to Kubernetes. It provides an overview of CI/CD pipelines for Kubernetes and how Helm can be used to package and deploy Kubernetes applications and their dependencies. The document includes an example Helm deployment pipeline with stages for building, testing, releasing container images, and deploying applications to staging and production environments in Kubernetes.

2. Continuous Delivery to
Kubernetes using
Helm
Adnan Abdulhussein - @prydonius

3. Agenda
•CI/CD on Kubernetes
•Helm recap
•Demo

5. CI/CD
•Run Unit/Functional Tests
… also for PRs
•Automatically Build and Push Images
•Rollout New Version

6. Code/config change
Build
Test
Push Docker image
Staging/QA deployment
Production deployment
Manual verification

7. Code/config change
Build
Test
Push Docker image
Staging/QA deployment
Production deployment
Manual verification

9. Kubernetes Resource Definitions
MongoDB
Service
resource
Database tier
Secret
resource
Deployment
resource
Application
Service
resource
Backend tier
Config Map
resource
Deployment
resource
Nginx
Service
resource
Frontend tier
Deployment
resource

10. Example: Kubernetes resource
apiVersion: v1
kind: Deployment
metadata:
name: my-app
spec:
replicas: 1
template:
metadata:
labels:
app: my-app
spec:
containers:
- name: my-app
image: prydonius/node-todo:v1.0.0
ports:
- containerPort: 80
livenessProbe:
httpGet:
path: /
port: http
initialDelaySeconds: 120
timeoutSeconds: 5

11. kubectl apply -f manifests/

12. sed -i.bak 's#prydonius/node-
todo:v1.0.0#${imageTag}#' deployment.yaml

13. Tool for managing
resources as a
single unit
● Reuse resources
● Logically group app resources
● Manage app lifecycles

14. Charts
(packages)
Application definitions
Consist of
Metadata (Chart.yaml)
Documentation
Kubernetes templates
Configuration file (values.yaml)
Can depend on other charts

15. helm install my-app --set image.tag=${imageTag}

17. Demo!

18. Pipeline Stages: Build
environment {
IMAGE_NAME = 'prydonius/node-todo'
}
stage('Build') {
agent any
steps {
checkout scm
sh 'docker build -t $IMAGE_NAME:$BUILD_ID .'
}
}

19. Pipeline Stages: Push
stage('Image Release') {
agent any
when {
expression { env.BRANCH_NAME == 'master' }
}
steps {
withCredentials([[$class: 'UsernamePasswordMultiBinding',
credentialsId: 'dockerhub',
usernameVariable: 'DOCKER_USERNAME', passwordVariable:
'DOCKER_PASSWORD']]) {
sh '''
docker login -u $DOCKER_USERNAME -p $DOCKER_PASSWORD
docker push $IMAGE_NAME:$BUILD_ID
'''
}
}
}
Only release master builds

20. Pipeline Stages: Staging Deployment
stage('Staging Deployment') {
...
environment {
RELEASE_NAME = 'todos-staging'
SERVER_HOST = 'todos.staging.k8s.prydoni.us'
}
steps {
sh '''
. ./helm/helm-init.sh
helm dependencies build ./helm/todo
helm upgrade --install --namespace staging $RELEASE_NAME ./helm/todo
--set image.tag=$BUILD_ID,ingress.host=$SERVER_HOST
'''
}
}

21. Pipeline Stages: Manual Verification
stage('Deploy to Production?') {
when {
expression { env.BRANCH_NAME == 'master' }
}
steps {
// Prevent any older builds from deploying to production
milestone(1)
input 'Deploy to Production?'
milestone(2)
}
}

22. Pipeline Stages: Production Deployment
stage('Production Deployment') {
...
environment {
RELEASE_NAME = 'todos-production'
SERVER_HOST = 'todos.k8s.prydoni.us'
}
steps {
sh '''
. ./helm/helm-init.sh
helm dependencies build ./helm/todo
helm upgrade --install --namespace production $RELEASE_NAME ./helm/todo
--set image.tag=$BUILD_ID,ingress.host=$SERVER_HOST
'''
}
}

23. Helm Community
• Over 140 contributors
• Helm 2.4.1 released last week!
• Slack channel: Kubernetes #helm-users
• Public dev meetings: Thursdays @ 9:30 pacific (5:30pm BST)
• Weekly updates & demos at SIG-Apps meetings:
Mondays @ 9am pacific (5pm BST)
Join
us!

24. Thank You