Helm包管理 #

Helm核心概念
    │
    ├── Chart
    │   └── 应用包，包含Kubernetes资源模板
    │
    ├── Release
    │   └── Chart的部署实例
    │
    ├── Repository
    │   └── Chart仓库
    │
    └── Values
        └── 配置参数

# macOS
brew install helm

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

# Windows
choco install kubernetes-helm

# 验证安装
helm version

# 添加仓库
helm repo add bitnami https://charts.bitnami.com/bitnami
helm repo add stable https://charts.helm.sh/stable

# 更新仓库
helm repo update

# 查看仓库
helm repo list

# 搜索Chart
helm search repo nginx

mychart/
├── Chart.yaml          # Chart元数据
├── values.yaml         # 默认配置值
├── charts/             # 依赖Chart
├── templates/          # 模板文件
│   ├── deployment.yaml
│   ├── service.yaml
│   ├── configmap.yaml
│   ├── ingress.yaml
│   └── _helpers.tpl    # 模板助手
└── templates/NOTES.txt # 安装说明

apiVersion: v2
name: mychart
description: 学习 Kubernetes 集群管理和编排，用于容器运维
type: application
version: 1.0.0
appVersion: "1.0.0"
maintainers:
  - name: maintainer
    email: maintainer@example.com
dependencies:
  - name: redis
    version: "16.x"
    repository: "https://charts.bitnami.com/bitnami"

replicaCount: 3

image:
  repository: nginx
  tag: "1.25"
  pullPolicy: IfNotPresent

service:
  type: ClusterIP
  port: 80

resources:
  limits:
    cpu: 200m
    memory: 256Mi
  requests:
    cpu: 100m
    memory: 128Mi

ingress:
  enabled: false
  className: ""
  hosts:
    - host: chart-example.local
      paths:
        - path: /
          pathType: ImplementationSpecific

# templates/deployment.yaml
apiVersion: apps/v1
kind: Deployment
metadata:
  name: {{ include "mychart.fullname" . }}
  labels:
    {{- include "mychart.labels" . | nindent 4 }}
spec:
  replicas: {{ .Values.replicaCount }}
  selector:
    matchLabels:
      {{- include "mychart.selectorLabels" . | nindent 6 }}
  template:
    metadata:
      labels:
        {{- include "mychart.selectorLabels" . | nindent 8 }}
    spec:
      containers:
        - name: {{ .Chart.Name }}
          image: "{{ .Values.image.repository }}:{{ .Values.image.tag }}"
          imagePullPolicy: {{ .Values.image.pullPolicy }}
          ports:
            - containerPort: {{ .Values.service.port }}

# 条件判断
{{- if .Values.ingress.enabled }}
apiVersion: networking.k8s.io/v1
kind: Ingress
metadata:
  name: {{ include "mychart.fullname" . }}
{{- end }}

# 循环
{{- range .Values.hosts }}
  - host: {{ .host }}
{{- end }}

# with作用域
{{- with .Values.ingress }}
ingress:
  enabled: {{ .enabled }}
{{- end }}

# templates/_helpers.tpl
{{- define "mychart.labels" -}}
app.kubernetes.io/name: {{ .Chart.Name }}
app.kubernetes.io/instance: {{ .Release.Name }}
app.kubernetes.io/version: {{ .Chart.AppVersion }}
{{- end }}

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

# 安装Chart
helm install myrelease mychart/

# 使用自定义values
helm install myrelease mychart/ -f values.yaml

# 设置参数
helm install myrelease mychart/ --set replicaCount=5

# 升级Release
helm upgrade myrelease mychart/

# 升级并安装（推荐）
helm upgrade --install myrelease mychart/

# 查看Release列表
helm list

# 查看Release状态
helm status myrelease

# 查看Release历史
helm history myrelease

# 查看Release values
helm get values myrelease

# 查看Release manifest
helm get manifest myrelease

# 回滚到上一版本
helm rollback myrelease

# 回滚到指定版本
helm rollback myrelease 2

# 删除Release
helm uninstall myrelease

# 保留历史记录删除
helm uninstall myrelease --keep-history

# 创建Chart骨架
helm create mychart

# 验证Chart
helm lint mychart/

# 打包Chart
helm package mychart/

# 测试渲染
helm template myrelease mychart/

# 调试渲染
helm template myrelease mychart/ --debug

# 干运行安装
helm install myrelease mychart/ --dry-run --debug

# 验证模板
helm lint mychart/

# Chart.yaml
dependencies:
  - name: redis
    version: "16.x"
    repository: "https://charts.bitnami.com/bitnami"
    condition: redis.enabled
    tags:
      - cache
  - name: postgresql
    version: "12.x"
    repository: "https://charts.bitnami.com/bitnami"
    condition: postgresql.enabled

# 下载依赖
helm dependency update mychart/

# 列出依赖
helm dependency list mychart/

# 构建依赖
helm dependency build mychart/

# 打包Chart
helm package mychart/

# 生成索引
helm repo index ./charts/

# 启动本地仓库
helm serve

# 添加仓库
helm repo add myrepo https://charts.example.com

# 更新仓库
helm repo update

# 搜索Chart
helm search repo mychart

Chart设计原则
    │
    ├── 单一职责
    │   └── 一个Chart一个应用
    │
    ├── 可配置性
    │   └── 使用values.yaml
    │
    ├── 版本控制
    │   └── 语义化版本
    │
    └── 文档完善
        └── README和NOTES

# 分层配置
# 默认值 -> 环境values -> 命令行参数

# 合理默认值
replicaCount: 1

# 资源限制
resources:
  limits:
    cpu: 200m
    memory: 256Mi
  requests:
    cpu: 100m
    memory: 128Mi

# 开关控制
ingress:
  enabled: false