Bits of .NET

📦 Helm = Kubernetes Package Manager

Kubernetes YAML is repetitive. Helm packages Kubernetes apps. Templates, versioning, sharing — like apt/yum for K8s.

📝 Helm Commands

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

# Add repositories
helm repo add bitnami https://charts.bitnami.com/bitnami
helm repo add stable https://charts.helm.sh/stable
helm repo update

# Search charts
helm search repo nginx
helm search hub nginx

# Install chart
helm install my-nginx bitnami/nginx
helm install my-postgres bitnami/postgresql

# List releases
helm list
helm list -n namespace

# Upgrade
helm upgrade my-nginx bitnami/nginx --set replicaCount=3

# Rollback
helm rollback my-nginx 1

# Uninstall
helm uninstall my-nginx

# View values
helm show values bitnami/nginx

# Create chart
helm create my-chart

🎯 Creating a Helm Chart

# Chart structure
my-chart/
├── Chart.yaml          # Chart metadata
├── values.yaml         # Default values
├── templates/          # Kubernetes templates
│   ├── deployment.yaml
│   ├── service.yaml
│   ├── configmap.yaml
│   └── _helpers.tpl    # Helper functions

# Chart.yaml
apiVersion: v2
name: my-app
description: My application
type: application
version: 0.1.0
appVersion: 1.16.0

# values.yaml
replicaCount: 1
image:
    repository: myapp
    tag: latest
    pullPolicy: IfNotPresent
service:
    type: ClusterIP
    port: 80
ingress:
    enabled: false
resources:
    limits:
        cpu: 100m
        memory: 128Mi

# templates/deployment.yaml
apiVersion: apps/v1
kind: Deployment
metadata:
    name: {{ include "my-app.fullname" . }}
    labels:
        app: {{ include "my-app.name" . }}
spec:
    replicas: {{ .Values.replicaCount }}
    selector:
        matchLabels:
            app: {{ include "my-app.name" . }}
    template:
        metadata:
            labels:
                app: {{ include "my-app.name" . }}
        spec:
            containers:
                - name: {{ .Chart.Name }}
                  image: "{{ .Values.image.repository }}:{{ .Values.image.tag }}"
                  imagePullPolicy: {{ .Values.image.pullPolicy }}
                  ports:
                    - containerPort: 80
                  resources:
                    {{- toYaml .Values.resources | nindent 12 }}

💡 Best Practices

• Use official repositories when possible
• Version your charts
• Use values.yaml for customization
• Test charts with helm test
• Store charts in Helm repo (ChartMuseum)