LAB14a: Using Helm to Deploy

LAB500a: Using helm to deploy hello-world static website

Method 1: Helm Templating Approach

Helm uses templating + values files, allowing each environment (dev/prod) to override:

• namespace

• domain

• SSL on/off

• index.html content

• name suffix

• labels

Helm Directory Structure

helm-website/
├── Chart.yaml
├── values.yaml
├── values-dev.yaml
├── values-prod.yaml
├── dev-index.html
├── prod-index.html
└── templates/
    ├── configmap.yaml
    ├── deployment.yaml
    ├── service.yaml
    └── ingress.yaml

1. Chart.yaml

apiVersion: v2
name: helm-helloworld
version: 1.0.0
description: Simple static website using Nginx

---

2. Base Values (values.yaml)

nameSuffix: ""
namespace: default
domain: example.com
enableTLS: false
contentFile: dev-index.html

---

3. Dev Environment Values (values-dev.yaml)

nameSuffix: "-dev"
namespace: "hello-dev"
domain: "dev.hello-world.xyz"
enableTLS: false
contentFile: "dev-index.html"

dev-index.html

Hello from Dev Environment

4. Prod Environment Values (values-prod.yaml)

nameSuffix: "-prod"
namespace: "hello-prod"
domain: "hello-world.xyz"
enableTLS: true
contentFile: "prod-index.html"

prod-index.html

Hello from Production Environment

5. Templates

templates/configmap.yaml

apiVersion: v1
kind: ConfigMap
metadata:
  name: website-config{{ .Values.nameSuffix }}
  namespace: {{ .Values.namespace }}
  labels:
    env: {{ trimPrefix "-" .Values.nameSuffix }}
data:
  index.html: |
{{ .Files.Get .Values.contentFile | indent 4 }}

Loads file-based content.

templates/deployment.yaml

apiVersion: apps/v1
kind: Deployment
metadata:
  name: website{{ .Values.nameSuffix }}
  namespace: {{ .Values.namespace }}
  labels:
    app: website
    env: {{ trimPrefix "-" .Values.nameSuffix }}
spec:
  replicas: 1
  selector:
    matchLabels:
      app: website
      env: {{ trimPrefix "-" .Values.nameSuffix }}
  template:
    metadata:
      labels:
        app: website
        env: {{ trimPrefix "-" .Values.nameSuffix }}
    spec:
      containers:
      - name: website
        image: nginx
        volumeMounts:
        - name: html
          mountPath: /usr/share/nginx/html
      volumes:
      - name: html
        configMap:
          name: website-config{{ .Values.nameSuffix }}

templates/service.yaml

apiVersion: v1
kind: Service
metadata:
  name: website-svc{{ .Values.nameSuffix }}
  namespace: {{ .Values.namespace }}
  labels:
    app: website
    env: {{ trimPrefix "-" .Values.nameSuffix }}
spec:
  ports:
    - port: 80
  selector:
    app: website
    env: {{ trimPrefix "-" .Values.nameSuffix }}

templates/ingress.yaml

apiVersion: networking.k8s.io/v1
kind: Ingress
metadata:
  name: website-ingress{{ .Values.nameSuffix }}
  namespace: {{ .Values.namespace }}
  labels:
    env: {{ trimPrefix "-" .Values.nameSuffix }}
spec:
  {{- if .Values.enableTLS }}
  tls:
    - hosts:
      - {{ .Values.domain }}
      secretName: website-tls
  {{- end }}
  rules:
    - host: {{ .Values.domain }}
      http:
        paths:
        - path: /
          pathType: Prefix
          backend:
            service:
              name: website-svc{{ .Values.nameSuffix }}
              port:
                number: 80

How to Deploy (Helm)

DEV Deployment

Preview first:

helm template website-dev ./helm-website -f values-dev.yaml

Deploy:

helm install website-dev ./helm-website -f values-dev.yaml

Verify:

kubectl get all -n hello-dev
kubectl get ingress -n hello-dev
kubectl get configmap -n hello-dev

---

PROD Deployment

Preview:

helm template website-prod ./helm-website -f values-prod.yaml

Deploy:

helm install website-prod ./helm-website -f values-prod.yaml

Verify:

kubectl get all -n hello-prod
kubectl get ingress -n hello-prod
kubectl get configmap -n hello-prod

Update Release

DEV:

helm upgrade website-dev ./helm-website -f values-dev.yaml

PROD:

helm upgrade website-prod ./helm-website -f values-prod.yaml

Uninstall

helm uninstall website-dev -n hello-dev
helm uninstall website-prod -n hello-prod