kubectl源码分析之set serviceaccount_kubectl set service-优快云博客

type SetServiceAccountOptions struct {//set serviceaccount结构体
	PrintFlags  *genericclioptions.PrintFlags
	RecordFlags *genericclioptions.RecordFlags

	fileNameOptions        resource.FilenameOptions
	dryRun                 bool
	shortOutput            bool
	all                    bool
	output                 string
	local                  bool
	updatePodSpecForObject polymorphichelpers.UpdatePodSpecForObjectFunc
	infos                  []*resource.Info
	serviceAccountName     string

	PrintObj printers.ResourcePrinterFunc
	Recorder genericclioptions.Recorder

	genericclioptions.IOStreams
}

func NewSetServiceAccountOptions(streams genericclioptions.IOStreams) *SetServiceAccountOptions {
	return &SetServiceAccountOptions{//初始化结构体
		PrintFlags:  genericclioptions.NewPrintFlags("serviceaccount updated").WithTypeSetter(scheme.Scheme),
		RecordFlags: genericclioptions.NewRecordFlags(),

		Recorder: genericclioptions.NoopRecorder{},

		IOStreams: streams,
	}
}

//创建set serviceaccount命令
func NewCmdServiceAccount(f cmdutil.Factory, streams genericclioptions.IOStreams) *cobra.Command {
	o := NewSetServiceAccountOptions(streams)//初始化结构体

	cmd := &cobra.Command{//创建cobra命令
		Use:                   "serviceaccount (-f FILENAME | TYPE NAME) SERVICE_ACCOUNT",
		DisableFlagsInUseLine: true,
		Aliases:               []string{"sa"},
		Short:                 i18n.T("Update ServiceAccount of a resource"),
		Long:                  serviceaccountLong,
		Example:               serviceaccountExample,
		Run: func(cmd *cobra.Command, args []string) {
			cmdutil.CheckErr(o.Complete(f, cmd, args))//准备
			cmdutil.CheckErr(o.Run())//运行
		},
	}

	o.PrintFlags.AddFlags(cmd)//设置print选项
	o.RecordFlags.AddFlags(cmd)//设置record选项

	usage := "identifying the resource to get from a server."
	cmdutil.AddFilenameOptionFlags(cmd, &o.fileNameOptions, usage)//设置文件选项
	cmd.Flags().BoolVar(&o.all, "all", o.all, "Select all resources, including uninitialized ones, in the namespace of the specified resource types")//设置all选项
	cmd.Flags().BoolVar(&o.local, "local", o.local, "If true, set serviceaccount will NOT contact api-server but run locally.")//设置local选项
	cmdutil.AddDryRunFlag(cmd)//设置干跑选项
	cmdutil.AddIncludeUninitializedFlag(cmd)
	return cmd
}

//准备
func (o *SetServiceAccountOptions) Complete(f cmdutil.Factory, cmd *cobra.Command, args []string) error {
	var err error

	o.RecordFlags.Complete(cmd)//record complete
	o.Recorder, err = o.RecordFlags.ToRecorder()//recordflag转recorder
	if err != nil {
		return err
	}

	o.shortOutput = cmdutil.GetFlagString(cmd, "output") == "name"//判断output是否为name
	o.dryRun = cmdutil.GetDryRunFlag(cmd)//设置干跑
	o.output = cmdutil.GetFlagString(cmd, "output")//设置output
	o.updatePodSpecForObject = polymorphichelpers.UpdatePodSpecForObjectFn//设置updatePodSpecforObject函数

	if o.dryRun {
		o.PrintFlags.Complete("%s (dry run)")
	}
	printer, err := o.PrintFlags.ToPrinter()//printflag转printer
	if err != nil {
		return err
	}
	o.PrintObj = printer.PrintObj//设置printObj函数

	cmdNamespace, enforceNamespace, err := f.ToRawKubeConfigLoader().Namespace()//获取namespace和enforceNamespace
	if err != nil {
		return err
	}
	if len(args) == 0 {//如果参数为空报错
		return errors.New("serviceaccount is required")
	}
	o.serviceAccountName = args[len(args)-1]
	resources := args[:len(args)-1]
	builder := f.NewBuilder().
		WithScheme(scheme.Scheme, scheme.Scheme.PrioritizedVersionsAllGroups()...).
		LocalParam(o.local).
		ContinueOnError().
		NamespaceParam(cmdNamespace).DefaultNamespace().
		FilenameParam(enforceNamespace, &o.fileNameOptions).
		Flatten()//构造info对象
	if !o.local {
		builder.ResourceTypeOrNameArgs(o.all, resources...).
			Latest()
	}
	o.infos, err = builder.Do().Infos()//设置info对象
	if err != nil {
		return err
	}
	return nil
}

func (o *SetServiceAccountOptions) Run() error {
	patchErrs := []error{}
	patchFn := func(obj runtime.Object) ([]byte, error) {//创建patch，修改海曙
		_, err := o.updatePodSpecForObject(obj, func(podSpec *v1.PodSpec) error {//更新pod spec
			podSpec.ServiceAccountName = o.serviceAccountName//更新serviceaccountName
			return nil
		})
		if err != nil {
			return nil, err
		}
		// record this change (for rollout history)
		if err := o.Recorder.Record(obj); err != nil {//判断是否创建change-cause注解
			klog.V(4).Infof("error recording current command: %v", err)
		}

		return runtime.Encode(scheme.DefaultJSONEncoder(), obj)//对象转json
	}

	patches := CalculatePatches(o.infos, scheme.DefaultJSONEncoder(), patchFn)//计算patch
	for _, patch := range patches {//遍历patch
		info := patch.Info
		name := info.ObjectName()
		if patch.Err != nil {//patch有错误则继续
			patchErrs = append(patchErrs, fmt.Errorf("error: %s %v\n", name, patch.Err))
			continue
		}
		if o.local || o.dryRun {//local或干跑则打印对象，继续
			if err := o.PrintObj(info.Object, o.Out); err != nil {
				patchErrs = append(patchErrs, err)
			}
			continue
		}
		actual, err := resource.NewHelper(info.Client, info.Mapping).Patch(info.Namespace, info.Name, types.StrategicMergePatchType, patch.Patch, nil)//应用patch到服务端
		if err != nil {
			patchErrs = append(patchErrs, fmt.Errorf("failed to patch ServiceAccountName %v", err))
			continue
		}

		if err := o.PrintObj(actual, o.Out); err != nil {//打印结果
			patchErrs = append(patchErrs, err)
		}
	}
	return utilerrors.NewAggregate(patchErrs)
}