K8s-解析云上初始化(keadm init)

什么是keadm init

keadm init通过keadm init可以实现初始化cloudcore。

解析keadm init过程

ExecuteInit就是真正执行init的方法，实际上是通过实现了InstallTools接口函数的方法实现的
所以InstallTools方法实现了init的进入函数
真正实现下载安装的函数是runHelmInstall

// IsKubeEdgeProcessRunning checks if the given process is running or not
func IsKubeEdgeProcessRunning(proc string) (bool, error) {
   //pidof是Linux系统中用来查找正在运行进程的进程号（pid)的工具 
  // proc=cloudcore
    procRunning := fmt.Sprintf("pidof %s 2>&1", proc)
    cmd := NewCommand(procRunning)

    err := cmd.Exec()
	// 通过退出码检查是否安装
    if cmd.ExitCode == 0 {
       return true, nil
    } else if cmd.ExitCode == 1 {
       return false, nil
    }

    return false, err
}

// 真正的拉起Kubeedge的Cloudcore
func (cu *KubeCloudHelmInstTool) runHelmInstall(r *Renderer) (*release.Release, error) {
    cf := genericclioptions.NewConfigFlags(true)
    cf.KubeConfig = &cu.Common.KubeConfig
    cf.Namespace = &cu.Namespace

    cfg := &action.Configuration{}
    // let the os.Stdout not print the details
    logFunc := func(format string, v ...interface{}) {}
    if err := cfg.Init(cf, cu.Namespace, "", logFunc); err != nil {
       return nil, err
    }

    // a flag to confirm the install/upgrade action
    var performInstall bool
    _, err := cfg.Releases.Last(r.componentName)
    if err != nil && errors.Is(err, driver.ErrReleaseNotFound) {
       performInstall = true
    }

    if performInstall {
       helmInstall := action.NewInstall(cfg)
       helmInstall.DryRun = cu.DryRun
       helmInstall.Namespace = cu.Namespace
       // --force would not wait.
       if !cu.Force {
          helmInstall.Wait = DefaultHelmWait
          helmInstall.Timeout = DefaultHelmTimeout
       }
       helmInstall.CreateNamespace = DefaultHelmCreateNs
       helmInstall.ReleaseName = r.componentName

       rel, err := helmInstall.Run(r.chart, r.profileValsMap)
       if err != nil {
          return nil, err
       }
       return rel, nil
    }

    // try to update a version
    helmUpgrade := action.NewUpgrade(cfg)
    helmUpgrade.DryRun = cu.DryRun
    helmUpgrade.Namespace = cu.Namespace
    // --force would not wait.
    if !cu.Force {
       helmUpgrade.Wait = DefaultHelmWait
       helmUpgrade.Timeout = DefaultHelmTimeout
    }

    rel, err := helmUpgrade.Run(r.componentName, r.chart, r.profileValsMap)
    if err != nil {
       return nil, err
    }
    return rel, nil
}