helm原理及实践

• 为什么用Helm
• Helm是什么
  • 简介
  • 设计目标
  • 架构
  • 核心概念
• 如何使用
  • 客户端命令使用

为什么用Helm

它使Kubernetes应用程序的配置、部署和维护变得更加简单、可控和可重复。

Helm是什么

简介

Helm是k8s的包管理工具，用于配置和部署复杂的应用程序、微服务和资源。

设计目标

Helm 的设计目标是使Kubernetes应用程序的配置和部署变得更加简单、可控和可重复，同时提供了一种标准的方法来管理和共享应用程序配置。

架构

Image from: https://developer.ibm.com/blogs/kubernetes-helm-3/

核心概念

如何使用

客户端命令使用

# 查看helm帮助命令
$ helm -h
The Kubernetes package manager

Common actions for Helm:

- helm search:    search for charts
- helm pull:      download a chart to your local directory to view
- helm install:   upload the chart to Kubernetes
- helm list:      list releases of charts

...

Usage:
  helm [command]

Available Commands:
  completion  generate autocompletion scripts for the specified shell
  create      create a new chart with the given name
  dependency  manage a chart's dependencies
  env         helm client environment information
  get         download extended information of a named release
  help        Help about any command
  history     fetch release history
  install     install a chart
  lint        examine a chart for possible issues
  list        list releases
  package     package a chart directory into a chart archive
  plugin      install, list, or uninstall Helm plugins
  pull        download a chart from a repository and (optionally) unpack it in local directory
  repo        add, list, remove, update, and index chart repositories
  rollback    roll back a release to a previous revision
  search      search for a keyword in charts
  show        show information of a chart
  status      display the status of the named release
  template    locally render templates
  test        run tests for a release
  uninstall   uninstall a release
  upgrade     upgrade a release
  verify      verify that a chart at the given path has been signed and is valid
  version     print the client version information

Flags:
      --debug                       enable verbose output
  -h, --help                        help for helm
  ...


# 添加helm仓库
helm repo add --username $HELM_REPO_USERNAME --password $HELM_REPO_PASSWORD helm_publish_test $HELM_REPO_ADDR
# 更新本地repo信息
helm repo update
# 推送chart包
curl -F "chart=nginx" -u $HELM_REPO_USERNAME:$HELM_REPO_PASSWORD $HELM_REPO_PUSH_DIR
# 安装chart包
helm install myapp helm_publish_test/<PACKAGE_NAME>
# 创建chart包
helm create mychart
# 搜索chart包
helm search repo nginx
# 列出chart包的所有版本
helm search repo bcs-webhook-server -l --devel # 包含开发包
# 查看release情况，-v 9用于打印调试日志信息（包含具体的API调用情况）
helm list -v 9
# 拉取chart包到本地
helm pull bitnami/nginx
# 查看本地或仓库中chart包的信息
helm show all bitnami/nginx | less
# 查看chart模版渲染后的内容
helm template my-release ./my-chart --values my-values.yaml
# 查看chart release
helm ls
# 获取已安装chart release的信息
helm get all my-nginx|less
# 打包chart,指定版本
helm package mychart --version 3.10.5
# 安装chart包
helm install -f nginx_values.yaml helm_publish_test/nginx