#!/bin/bash
# Helm commands
# Add repositories
helm repo add bitnami https://charts.bitnami.com/bitnami
helm repo update
# Install chart
helm install web-app ./charts/web-app --namespace production --create-namespace --values values-production.yaml
# Upgrade
helm upgrade web-app ./charts/web-app --namespace production --values values-production.yaml --set image.tag=1.3.0
# Rollback
helm rollback web-app 1 --namespace production
# List releases
helm list --namespace production
# Show values
helm get values web-app --namespace production
# Template (render without installing)
helm template web-app ./charts/web-app --values values-production.yaml
# Uninstall
helm uninstall web-app --namespace production
# Package chart
helm package ./charts/web-app
helm push web-app-0.3.0.tgz oci://registry.example.com/charts
# Update dependencies
helm dependency update ./charts/web-app
apiVersion: v2
name: web-app
description: A Helm chart for the web application
type: application
version: 0.3.0
appVersion: "1.2.0"
dependencies:
- name: postgresql
version: "13.x.x"
repository: https://charts.bitnami.com/bitnami
condition: postgresql.enabled
- name: redis
version: "18.x.x"
repository: https://charts.bitnami.com/bitnami
condition: redis.enabled
# Default values for web-app
replicaCount: 3
image:
repository: registry.example.com/web-app
tag: "1.2.0"
pullPolicy: IfNotPresent
service:
type: ClusterIP
port: 80
targetPort: 3000
ingress:
enabled: true
className: nginx
annotations:
cert-manager.io/cluster-issuer: letsencrypt-prod
hosts:
- host: app.example.com
paths:
- path: /
pathType: Prefix
tls:
- secretName: app-tls
hosts:
- app.example.com
resources:
requests:
cpu: 250m
memory: 256Mi
limits:
cpu: 500m
memory: 512Mi
autoscaling:
enabled: true
minReplicas: 3
maxReplicas: 20
targetCPUUtilizationPercentage: 70
env:
NODE_ENV: production
LOG_LEVEL: info
secrets:
databaseUrl: ""
jwtSecret: ""
postgresql:
enabled: true
auth:
database: myapp
primary:
persistence:
size: 20Gi
redis:
enabled: true
architecture: standalone
master:
persistence:
size: 5Gi
apiVersion: apps/v1
kind: Deployment
metadata:
name: {{ include "web-app.fullname" . }}
labels:
{{- include "web-app.labels" . | nindent 4 }}
spec:
{{- if not .Values.autoscaling.enabled }}
replicas: {{ .Values.replicaCount }}
{{- end }}
selector:
matchLabels:
{{- include "web-app.selectorLabels" . | nindent 6 }}
template:
metadata:
labels:
{{- include "web-app.selectorLabels" . | nindent 8 }}
annotations:
checksum/config: {{ include (print $.Template.BasePath "/configmap.yaml") . | sha256sum }}
spec:
containers:
- name: {{ .Chart.Name }}
image: "{{ .Values.image.repository }}:{{ .Values.image.tag }}"
imagePullPolicy: {{ .Values.image.pullPolicy }}
ports:
- name: http
containerPort: {{ .Values.service.targetPort }}
envFrom:
- configMapRef:
name: {{ include "web-app.fullname" . }}
- secretRef:
name: {{ include "web-app.fullname" . }}
resources:
{{- toYaml .Values.resources | nindent 12 }}
readinessProbe:
httpGet:
path: /health
port: http
initialDelaySeconds: 5
periodSeconds: 10
livenessProbe:
httpGet:
path: /health
port: http
initialDelaySeconds: 15
periodSeconds: 20
Helm is the package manager for Kubernetes, bundling manifests into reusable charts. A Chart.yaml defines chart metadata and dependencies. values.yaml provides default configuration that users can override. Templates in the templates/ directory use Go template syntax with {{ .Values.key }}. _helpers.tpl defines reusable template functions. helm install deploys a chart, helm upgrade updates it. helm rollback reverts to a previous release. helm repo add registers chart repositories. The --set flag overrides values at install time. Subcharts in charts/ manage dependencies. Hooks run jobs at lifecycle events like pre-install and post-upgrade. Helm simplifies deploying complex applications with configurable, versioned packages.
