কুবারনেটস হেলম গাইড 2026: চার্ট, মান এবং উত্পাদন স্থাপনা

# macOS
brew install helm

# Linux
curl https://raw.githubusercontent.com/helm/helm/main/scripts/get-helm-3 | bash

# Verify
helm version

# Add popular repositories
helm repo add stable https://charts.helm.sh/stable
helm repo add bitnami https://charts.bitnami.com/bitnami
helm repo add prometheus-community https://prometheus-community.github.io/helm-charts
helm repo update

# Search for charts
helm search repo postgres
helm search hub nginx

# Install PostgreSQL
helm install my-postgres bitnami/postgresql   --namespace database   --create-namespace   --set auth.postgresPassword=secretpassword   --set primary.persistence.size=20Gi

# Install with custom values file
helm install my-app ./my-chart -f values.prod.yaml

# Check release status
helm list -n database
helm status my-postgres -n database

# Get notes after install
helm get notes my-postgres -n database

# Upgrade release
helm upgrade my-postgres bitnami/postgresql   --namespace database   --set auth.postgresPassword=newpassword

# Rollback
helm rollback my-postgres 1  # rollback to revision 1

# Uninstall
helm uninstall my-postgres -n database

# Scaffold a new chart
helm create myapp

# Structure:
# myapp/
#   Chart.yaml          - chart metadata
#   values.yaml         - default values
#   templates/          - Kubernetes manifests (templated)
#     deployment.yaml
#     service.yaml
#     ingress.yaml
#     _helpers.tpl      - template helpers
#     NOTES.txt         - post-install notes
#   charts/             - dependency charts
#   .helmignore

apiVersion: v2
name: myapp
description: My production application
type: application
version: 0.1.0      # chart version (semver)
appVersion: "1.2.3"  # app version

dependencies:
  - name: postgresql
    version: "13.x.x"
    repository: https://charts.bitnami.com/bitnami
    condition: postgresql.enabled

  - name: redis
    version: "17.x.x"
    repository: https://charts.bitnami.com/bitnami
    condition: redis.enabled

replicaCount: 2

image:
  repository: mycompany/myapp
  tag: "1.2.3"
  pullPolicy: IfNotPresent

service:
  type: ClusterIP
  port: 8000

ingress:
  enabled: true
  className: nginx
  annotations:
    cert-manager.io/cluster-issuer: letsencrypt-prod
  hosts:
    - host: myapp.example.com
      paths:
        - path: /
          pathType: Prefix
  tls:
    - secretName: myapp-tls
      hosts:
        - myapp.example.com

resources:
  limits:
    cpu: 500m
    memory: 512Mi
  requests:
    cpu: 100m
    memory: 128Mi

autoscaling:
  enabled: true
  minReplicas: 2
  maxReplicas: 10
  targetCPUUtilizationPercentage: 70

postgresql:
  enabled: true
  auth:
    database: myapp_db
    existingSecret: myapp-db-secret

redis:
  enabled: true
  architecture: standalone

# templates/deployment.yaml
apiVersion: apps/v1
kind: Deployment
metadata:
  name: {{ include "myapp.fullname" . }}
  labels:
    {{- include "myapp.labels" . | nindent 4 }}
spec:
  {{- if not .Values.autoscaling.enabled }}
  replicas: {{ .Values.replicaCount }}
  {{- end }}
  selector:
    matchLabels:
      {{- include "myapp.selectorLabels" . | nindent 6 }}
  template:
    metadata:
      labels:
        {{- include "myapp.selectorLabels" . | nindent 8 }}
    spec:
      containers:
        - name: {{ .Chart.Name }}
          image: "{{ .Values.image.repository }}:{{ .Values.image.tag }}"
          imagePullPolicy: {{ .Values.image.pullPolicy }}
          ports:
            - containerPort: {{ .Values.service.port }}
          env:
            - name: DATABASE_URL
              valueFrom:
                secretKeyRef:
                  name: myapp-db-secret
                  key: database-url
            - name: APP_VERSION
              value: {{ .Chart.AppVersion | quote }}
          resources:
            {{- toYaml .Values.resources | nindent 12 }}
          livenessProbe:
            httpGet:
              path: /health
              port: {{ .Values.service.port }}
            initialDelaySeconds: 30
            periodSeconds: 10

# values.dev.yaml — development overrides
# helm install myapp ./myapp -f values.yaml -f values.dev.yaml

# values.prod.yaml — production overrides
# helm install myapp ./myapp -f values.yaml -f values.prod.yaml

# values.prod.yaml
replicaCount: 5

image:
  tag: "1.2.3-stable"

resources:
  limits:
    cpu: 2000m
    memory: 2Gi
  requests:
    cpu: 500m
    memory: 512Mi

autoscaling:
  enabled: true
  minReplicas: 5
  maxReplicas: 50

# .github/workflows/deploy.yml
- name: Deploy with Helm
  run: |
    helm upgrade --install myapp ./charts/myapp       --namespace production       --create-namespace       --set image.tag=${{ github.sha }}       --set image.repository=ghcr.io/${{ github.repository }}       -f values.prod.yaml       --wait       --timeout 10m       --atomic  # rollback automatically on failure

# Lint chart before install
helm lint ./myapp

# Render templates without installing
helm template myapp ./myapp -f values.prod.yaml

# Diff current vs proposed changes
helm plugin install https://github.com/databus23/helm-diff
helm diff upgrade myapp ./myapp -f values.prod.yaml

# Show all values (defaults + overrides)
helm get values myapp -n production --all

# History
helm history myapp -n production