Implementing Chart Best Practices

apiVersion: v2
name: myapp
description: A Helm chart for myapp
version: 1.2.3
appVersion: 2.0.1

{{- define "myapp.fullname" -}}
{{- if .Values.fullnameOverride }}
{{- .Values.fullnameOverride | trunc 63 | trimSuffix "-" }}
{{- else }}
{{- $name := default .Chart.Name .Values.nameOverride }}
{{- if contains $name .Release.Name }}
{{- .Release.Name }}
{{- else }}
{{- printf "%s-%s" .Release.Name $name | trunc 63 | trimSuffix "-" }}
{{- end }}
{{- end }}
{{- end }}

apiVersion: apps/v1
kind: Deployment
metadata:
  name: {{ include "myapp.fullname" . }}
  labels:
    app.kubernetes.io/name: {{ include "myapp.name" . }}
    app.kubernetes.io/instance: {{ .Release.Name }}
    app.kubernetes.io/version: "{{ .Chart.AppVersion }}"
    app.kubernetes.io/component: frontend
    app.kubernetes.io/part-of: myapp
    app.kubernetes.io/managed-by: {{ .Release.Service }}
spec:
  replicas: {{ .Values.replicaCount }}
  selector:
    matchLabels:
      app.kubernetes.io/name: {{ include "myapp.name" . }}
      app.kubernetes.io/instance: {{ .Release.Name }}
  template:
    metadata:
      labels:
        app.kubernetes.io/name: {{ include "myapp.name" . }}
        app.kubernetes.io/instance: {{ .Release.Name }}
        app.kubernetes.io/version: "{{ .Chart.AppVersion }}"
        app.kubernetes.io/component: frontend

annotations:
  helm.sh/chart: "myapp-1.2.3"
  app.kubernetes.io/name: "myapp"
  app.kubernetes.io/version: "v1.2.3"
  app.kubernetes.io/managed-by: "helm"

replicaCount: 2
image:
  repository: myapp
  tag: v1.0.0
service:
  type: LoadBalancer
resources:
  limits:
    cpu: 1000m
    memory: 1Gi
  requests:
    cpu: 500m
    memory: 256Mi

replicaCount: 1
image:
  repository: nginx
  tag: latest
service:
  type: ClusterIP
  port: 80
resources:
  limits:
    cpu: 500m
    memory: 512Mi
  requests:
    cpu: 250m
    memory: 256Mi

# MyChart

A Helm chart for deploying MyApplication.

## Prerequisites

- Kubernetes 1.20+
- Helm 3.0+

## Installing the Chart

To install the chart:

```bash
helm install my-release ./my-chart
```

## Configuration

The following table lists the configurable parameters of the chart and their default values.

### Parameters

| Name                      | Description                         | Value     |
| ------------------------- | ----------------------------------- | --------- |
| `replicaCount`            | Number of replicas                  | `1`       |
| `image.repository`        | Image repository                    | `nginx`   |
| `image.tag`               | Image tag                           | `latest`  |

# Default values for my-chart.
# This is a YAML-formatted file.
# Declare variables to be passed into your templates.

replicaCount: 1

image:
  repository: nginx
  pullPolicy: IfNotPresent
  # Overrides the image tag whose default is the chart appVersion.
  tag: ""

service:
  type: ClusterIP
  port: 80

# Additional annotations for resources
annotations: {}

Thank you for installing {{ .Chart.Name }}.

Your release is named {{ .Release.Name }}.

To learn more about the release, try:

  helm status {{ .Release.Name }}
  helm get all {{ .Release.Name }}

Get the application URL by running these commands:
{{- if .Values.ingress.enabled }}
  {{- range $host := .Values.ingress.hosts }}
  http{{ if $.Values.ingress.tls }}s{{ end }}://{{ $host.host }}{{ $host.path }}
  {{- end }}
{{- else if contains "NodePort" .Values.service.type }}
  export NODE_PORT=$(kubectl get --namespace {{ .Release.Namespace }} -o jsonpath="{.spec.ports[0].nodePort}" services {{ include "myapp.fullname" . }})
  export NODE_IP=$(kubectl get nodes --namespace {{ .Release.Namespace }} -o jsonpath="{.items[0].status.addresses[0].address}")
  echo http://$NODE_IP:$NODE_PORT
{{- else if contains "LoadBalancer" .Values.service.type }}
  export SERVICE_IP=$(kubectl get svc --namespace {{ .Release.Namespace }} {{ include "myapp.fullname" . }} -o jsonpath="{.status.loadBalancer.ingress[0].hostname}")
  echo http://$SERVICE_IP:{{ .Values.service.port }}
{{- else if contains "ClusterIP" .Values.service.type }}
  export POD_NAME=$(kubectl get pods --namespace {{ .Release.Namespace }} -l "app.kubernetes.io/name={{ include "myapp.name" . }},app.kubernetes.io/instance={{ .Release.Name }}" -o jsonpath="{.items[0].metadata.name}")
  echo "Visit http://127.0.0.1:8080 to use your application"
  kubectl --namespace {{ .Release.Namespace }} port-forward $POD_NAME 8080:80
{{- end }}

resources:
  requests:
    memory: "64Mi"
    cpu: "250m"
  limits:
    memory: "128Mi"
    cpu: "500m"

healthCheck:
  livenessProbe:
    httpGet:
      path: /health
      port: 8080
    initialDelaySeconds: 30
    periodSeconds: 10
  readinessProbe:
    tcpSocket:
      port: 8080
    initialDelaySeconds: 5
    periodSeconds: 5

apiVersion: v2
name: my-app
description: A Helm chart for my application
type: application
version: 1.0.0
appVersion: "1.0"

replicaCount: 1
image:
  repository: nginx
  tag: "1.20"
service:
  type: ClusterIP
  port: 80