• KubeSphere Helm 应用仓库源码分析


    作者:蔡锡生,LStack 平台研发工程师,近期专注于基于 OAM 的应用托管平台落地。

    背景介绍

    KubeSphere 应用商店简介

    作为一个开源的、以应用为中心的容器平台,KubeSphere 在 OpenPitrix 的基础上,为用户提供了一个基于 Helm 的应用商店,用于应用生命周期管理。OpenPitrix 是一个开源的 Web 平台,用于打包、部署和管理不同类型的应用。KubeSphere 应用商店让 ISV、开发者和用户能够在一站式服务中只需点击几下就可以上传、测试、部署和发布应用。

    KubeSphere 中的 Helm 仓库功能

    默认情况下,应用商店中内置了 16 个应用,但您可以通过应用模板添加更多应用。

    • KubeSphere Helm 仓库添加

    • Helm repo list

    • KubeSphere Helm 仓库中的应用模版查询

    Helm 仓库简介

    Helm charts 是存放 K8s 应用模版的仓库,该仓库由 index.yaml 文件和 .tgz 模版包组成。

    [root@ningbo stable]# ls -al 
    总用量 400
    drwxr-xr-x. 26 root root   4096 6月  22 17:01 .
    drwxr-xr-x.  4 root root     86 6月  22 16:37 ..
    -rw-r--r--.  1 root root  10114 6月  22 17:12 index.yaml
    -rw-r--r--.  1 root root   3803 6月   8 2020 lsh-cluster-csm-om-agent-0.1.0.tgz
    -rw-r--r--.  1 root root   4022 6月   8 2020 lsh-mcp-cc-alert-service-0.1.0.tgz
    -rw-r--r--.  1 root root   4340 6月   8 2020 lsh-mcp-cc-sms-service-0.1.0.tgz
    -rw-r--r--.  1 root root   4103 6月   8 2020 lsh-mcp-cpm-metrics-exchange-0.1.0.tgz
    -rw-r--r--.  1 root root   4263 6月   8 2020 lsh-mcp-cpm-om-service-0.1.0.tgz
    -rw-r--r--.  1 root root   4155 6月   8 2020 lsh-mcp-csm-om-service-0.1.0.tgz
    -rw-r--r--.  1 root root   3541 6月   8 2020 lsh-mcp-deploy-service-0.1.0.tgz
    -rw-r--r--.  1 root root   5549 6月   8 2020 lsh-mcp-iam-apigateway-service-0.1.0.tgz
    
    • index.yaml 文件
    apiVersion: v1
    entries:
      aliyun-ccm:
      - apiVersion: v2
        appVersion: addon
        created: "2021-06-21T08:59:58Z"
        description: A Helm chart for Kubernetes
        digest: 6bda563c86333475255e5edfedc200ae282544e2c6e22b519a59b3c7bdef9a32
        name: aliyun-ccm
        type: application
        urls:
        - charts/aliyun-ccm-0.1.0.tgz
        version: 0.1.0
      aliyun-csi-driver:
      - apiVersion: v2
        appVersion: addon
        created: "2021-06-21T08:59:58Z"
        description: A Helm chart for Kubernetes
        digest: b49f128d7a49401d52173e6f58caedd3fabbe8e2827dc00e6a824ee38860fa51
        name: aliyun-csi-driver
        type: application
        urls:
        - charts/aliyun-csi-driver-0.1.0.tgz
        version: 0.1.0
      application-controller:
      - apiVersion: v1
        appVersion: addon
        created: "2021-06-21T08:59:58Z"
        description: A Helm chart for application Controller
        digest: 546e72ce77f865683ce0ea75f6e0203537a40744f2eb34e36a5bd378f9452bc5
        name: application-controller
        urls:
        - charts/application-controller-0.1.0.tgz
        version: 0.1.0
    
    • .tgz 解压缩后的文件目录
    [root@ningbo stable]# cd mysql/
    [root@ningbo mysql]# ls -al
    总用量 20
    drwxr-xr-x.  3 root root   97 5月  25 2020 .
    drwxr-xr-x. 26 root root 4096 6月  22 17:01 ..
    -rwxr-xr-x.  1 root root  106 5月  25 2020 Chart.yaml
    -rwxr-xr-x.  1 root root  364 5月  25 2020 .Helmignore
    -rwxr-xr-x.  1 root root   76 5月  25 2020 index.yaml
    drwxr-xr-x.  3 root root  146 5月  25 2020 templates
    -rwxr-xr-x.  1 root root 1735 5月  25 2020 values.yaml
    
    • Chart.yaml
    [root@ningbo mysql]# cat Chart.yaml 
    apiVersion: v1
    appVersion: "1.0"
    description: A Helm chart for Kubernetes
    name: mysql
    version: 0.1.0
    

    添加 Helm 仓库代码介绍

    接口实现分析

    1. 路由注册
    2. handler,参数解析,调用 models 方面
    3. models ,调用 models 方法
    4. crd client,调用 K8s api 存储
        webservice.Route(webservice.POST("/repos").
            To(handler.CreateRepo). // 跟进
            Doc("Create a global repository, which is used to store package of app").
            Metadata(restfulspec.KeyOpenAPITags, []string{constants.OpenpitrixTag}).
            Param(webservice.QueryParameter("validate", "Validate repository")).
            Returns(http.StatusOK, api.StatusOK, openpitrix.CreateRepoResponse{}).
            Reads(openpitrix.CreateRepoRequest{}))
    
    func (h *openpitrixHandler) CreateRepo(req *restful.Request, resp *restful.Response) {
    
        createRepoRequest := &openpitrix.CreateRepoRequest{}
        err := req.ReadEntity(createRepoRequest)
        if err != nil {
            klog.V(4).Infoln(err)
            api.HandleBadRequest(resp, nil, err)
            return
        }
    
        createRepoRequest.Workspace = new(string)
        *createRepoRequest.Workspace = req.PathParameter("workspace")
    
        user, _ := request.UserFrom(req.Request.Context())
        creator := ""
        if user != nil {
            creator = user.GetName()
        }
        parsedUrl, err := url.Parse(createRepoRequest.URL)
        if err != nil {
            api.HandleBadRequest(resp, nil, err)
            return
        }
        userInfo := parsedUrl.User
        // trim credential from url
        parsedUrl.User = nil
    
        repo := v1alpha1.HelmRepo{
            ObjectMeta: metav1.ObjectMeta{
                Name: idutils.GetUuid36(v1alpha1.HelmRepoIdPrefix),
                Annotations: map[string]string{
                    constants.CreatorAnnotationKey: creator,
                },
                Labels: map[string]string{
                    constants.WorkspaceLabelKey: *createRepoRequest.Workspace,
                },
            },
            Spec: v1alpha1.HelmRepoSpec{
                Name:        createRepoRequest.Name,
                Url:         parsedUrl.String(),
                SyncPeriod:  0,
                Description: stringutils.ShortenString(createRepoRequest.Description, 512),
            },
        }
    
        if strings.HasPrefix(createRepoRequest.URL, "https://") || strings.HasPrefix(createRepoRequest.URL, "http://") {
            if userInfo != nil {
                repo.Spec.Credential.Username = userInfo.Username()
                repo.Spec.Credential.Password, _ = userInfo.Password()
            }
        } else if strings.HasPrefix(createRepoRequest.URL, "s3://") {
            cfg := v1alpha1.S3Config{}
            err := json.Unmarshal([]byte(createRepoRequest.Credential), &cfg)
            if err != nil {
                api.HandleBadRequest(resp, nil, err)
                return
            }
            repo.Spec.Credential.S3Config = cfg
        }
    
        var result interface{}
        // 1. validate repo
        result, err = h.openpitrix.ValidateRepo(createRepoRequest.URL, &repo.Spec.Credential)
        if err != nil {
            klog.Errorf("validate repo failed, err: %s", err)
            api.HandleBadRequest(resp, nil, err)
            return
        }
    
        // 2. create repo
        validate, _ := strconv.ParseBool(req.QueryParameter("validate"))
        if !validate {
            if repo.GetTrueName() == "" {
                api.HandleBadRequest(resp, nil, fmt.Errorf("repo name is empty"))
                return
            }
            result, err = h.openpitrix.CreateRepo(&repo) //跟进
        }
    
        if err != nil {
            klog.Errorln(err)
            handleOpenpitrixError(resp, err)
            return
        }
    
        resp.WriteEntity(result)
    }
    
    func (c *repoOperator) CreateRepo(repo *v1alpha1.HelmRepo) (*CreateRepoResponse, error) {
        name := repo.GetTrueName()
    
        items, err := c.repoLister.List(labels.SelectorFromSet(map[string]string{constants.WorkspaceLabelKey: repo.GetWorkspace()}))
        if err != nil && !apierrors.IsNotFound(err) {
            klog.Errorf("list Helm repo failed: %s", err)
            return nil, err
        }
    
        for _, exists := range items {
            if exists.GetTrueName() == name {
                klog.Error(repoItemExists, "name: ", name)
                return nil, repoItemExists
            }
        }
    
        repo.Spec.Description = stringutils.ShortenString(repo.Spec.Description, DescriptionLen)
        _, err = c.repoClient.HelmRepos().Create(context.TODO(), repo, metav1.CreateOptions{}) // 跟进
        if err != nil {
            klog.Errorf("create Helm repo failed, repo_id: %s, error: %s", repo.GetHelmRepoId(), err)
            return nil, err
        } else {
            klog.V(4).Infof("create Helm repo success, repo_id: %s", repo.GetHelmRepoId())
        }
    
        return &CreateRepoResponse{repo.GetHelmRepoId()}, nil
    }
    
    // Create takes the representation of a HelmRepo and creates it.  Returns the server's representation of the HelmRepo, and an error, if there is any.
    func (c *HelmRepos) Create(ctx context.Context, HelmRepo *v1alpha1.HelmRepo, opts v1.CreateOptions) (result *v1alpha1.HelmRepo, err error) {
        result = &v1alpha1.HelmRepo{}
        err = c.client.Post().
            Resource("Helmrepos").
            VersionedParams(&opts, scheme.ParameterCodec).
            Body(HelmRepo).
            Do(ctx).
            Into(result)
        return
    }
    

    查询Helm 仓库应用模版代码介绍

    接口实现

    1. 路由注册
    2. handler,参数解析,调用 models 方面
    3. models ,调用 models 方法
    4. crd client,调用 K8s api 存储
    webservice.Route(webservice.GET("/apps").LiHui, 6 months ago: • openpitrix crd
            Deprecate().
            To(handler.ListApps).  // 跟进
            Doc("List app templates").
            Param(webservice.QueryParameter(params.ConditionsParam, "query conditions,connect multiple conditions with commas, equal symbol for exact query, wave symbol for fuzzy query e.g. name~a").
                Required(false).
                DataFormat("key=%s,key~%s")).
            Param(webservice.QueryParameter(params.PagingParam, "paging query, e.g. limit=100,page=1").
                Required(false).
                DataFormat("limit=%d,page=%d").
                DefaultValue("limit=10,page=1")).
            Param(webservice.QueryParameter(params.ReverseParam, "sort parameters, e.g. reverse=true")).
            Param(webservice.QueryParameter(params.OrderByParam, "sort parameters, e.g. orderBy=createTime")).
            Metadata(restfulspec.KeyOpenAPITags, []string{constants.OpenpitrixTag}).
            Returns(http.StatusOK, api.StatusOK, models.PageableResponse{}))
    
    func (h *openpitrixHandler) ListApps(req *restful.Request, resp *restful.Response)
        limit, offset := params.ParsePaging(req)
        orderBy := params.GetStringValueWithDefault(req, params.OrderByParam, openpitrix.CreateTime)
        reverse := params.GetBoolValueWithDefault(req, params.ReverseParam, false)
        conditions, err := params.ParseConditions(req)
    
        if err != nil {
            klog.V(4).Infoln(err)
            api.HandleBadRequest(resp, nil, err)
            return
        }
    
        if req.PathParameter("workspace") != "" {
            conditions.Match[openpitrix.WorkspaceLabel] = req.PathParameter("workspace")
        }
    
        result, err := h.openpitrix.ListApps(conditions, orderBy, reverse, limit, offset)  // 跟进
    
        if err != nil {
            klog.Errorln(err)
            handleOpenpitrixError(resp, err)
            return
        }
    
        resp.WriteEntity(result)
    }
    
    func (c *applicationOperator) ListApps(conditions *params.Conditions, orderBy string, reverse bool, limit, offset int) (*models.PageableResponse, error) {
    
        apps, err := c.listApps(conditions)  // 重点跟进
        if err != nil {
            klog.Error(err)
            return nil, err
        }
        apps = filterApps(apps, conditions)
    
        if reverse {
            sort.Sort(sort.Reverse(HelmApplicationList(apps)))
        } else {
            sort.Sort(HelmApplicationList(apps))
        }
    
        totalCount := len(apps)
        start, end := (&query.Pagination{Limit: limit, Offset: offset}).GetValidPagination(totalCount)
        apps = apps[start:end]
        items := make([]interface{}, 0, len(apps))
    
        for i := range apps {
            versions, err := c.getAppVersionsByAppId(apps[i].GetHelmApplicationId())
            if err != nil && !apierrors.IsNotFound(err) {
                return nil, err
            }
            ctg, _ := c.ctgLister.Get(apps[i].GetHelmCategoryId())
            items = append(items, convertApp(apps[i], versions, ctg, 0))
        }
        return &models.PageableResponse{Items: items, TotalCount: totalCount}, nil
    }
    
    // line 601
    func (c *applicationOperator) listApps(conditions *params.Conditions) (ret []*v1alpha1.HelmApplication, err error) {
        repoId := conditions.Match[RepoId]
        if repoId != "" && repoId != v1alpha1.AppStoreRepoId {
            // get Helm application from Helm repo
            if ret, exists := c.cachedRepos.ListApplicationsByRepoId(repoId); !exists {
                klog.Warningf("load repo failed, repo id: %s", repoId)
                return nil, loadRepoInfoFailed
            } else {
                return ret, nil
            }
        } else {
            if c.backingStoreClient == nil {
                return []*v1alpha1.HelmApplication{}, nil
            }
            ret, err = c.appLister.List(labels.SelectorFromSet(buildLabelSelector(conditions)))
        }
    
        return
    }
    
    func (c *cachedRepos) ListApplicationsByRepoId(repoId string) (ret []*v1alpha1.HelmApplication, exists bool) {
        c.RLock()
        defer c.RUnlock()
    
        if repo, exists := c.repos[repoId]; !exists {
            return nil, false
        } else {
            ret = make([]*v1alpha1.HelmApplication, 0, 10)
            for _, app := range c.apps {
                if app.GetHelmRepoId() == repo.Name { // 应用的仓库ID相同则追加
                    ret = append(ret, app)
                }
            }
        }
        return ret, true
    }
    

    既然 app template 是从缓存中获取的,那么缓存中的数据又是什么时候录入的呢?

    1. 创建全局缓存变量
    2. 添加新 Helm 仓库,K8s 中已安装 crd 控制器 HelmRepoController 发现有新的 HelmRepo 创建,更新 .Status.Data 内容
    3. informer 发现有更新,同时更新缓存

    缓存更新的实现

    1. 创建全局变量,通过 init 函数初始化
    2. 通过 HelmRepo 的 informer 实现缓存同步更新
    3. 在每次调用接口的时候,hanlder 类中包换了缓存变量

    创建接口类 openpitrix.Interface

    type openpitrixHandler struct {
        openpitrix openpitrix.Interface
    }
    
    func newOpenpitrixHandler(ksInformers informers.InformerFactory, ksClient versioned.Interface, option *openpitrixoptions.Options) *openpitrixHandler {
        var s3Client s3.Interface
        if option != nil && option.S3Options != nil && len(option.S3Options.Endpoint) != 0 {
            var err error
            s3Client, err = s3.NewS3Client(option.S3Options)
            if err != nil {
                klog.Errorf("failed to connect to storage, please check storage service status, error: %v", err)
            }
        }
    
        return &openpitrixHandler{
            openpitrix.NewOpenpitrixOperator(ksInformers, ksClient, s3Client),
        }
    }
    

    NewOpenpitrixOperator

    • 通过在 informer 中添加通知函数,执行缓存更新
    • once.Do 只执行一次
    var cachedReposData reposcache.ReposCache
    var HelmReposInformer cache.SharedIndexInformer
    var once sync.Once
    
    
    func init() {
        cachedReposData = reposcache.NewReposCache() // 全局缓存
    }
    
    func NewOpenpitrixOperator(ksInformers ks_informers.InformerFactory, ksClient versioned.Interface, s3Client s3.Interface) Interface {
    
        once.Do(func() {
            klog.Infof("start Helm repo informer")
            HelmReposInformer = ksInformers.KubeSphereSharedInformerFactory().Application().V1alpha1().HelmRepos().Informer()
            HelmReposInformer.AddEventHandler(cache.ResourceEventHandlerFuncs{
                AddFunc: func(obj interface{}) {
                    r := obj.(*v1alpha1.HelmRepo)
                    cachedReposData.AddRepo(r) // 缓存更新, 点击跟进
                },
                UpdateFunc: func(oldObj, newObj interface{}) {
                    oldR := oldObj.(*v1alpha1.HelmRepo)
                    cachedReposData.DeleteRepo(oldR)
                    r := newObj.(*v1alpha1.HelmRepo)
                    cachedReposData.AddRepo(r)
                },
                DeleteFunc: func(obj interface{}) {
                    r := obj.(*v1alpha1.HelmRepo)
                    cachedReposData.DeleteRepo(r)
                },
            })
            go HelmReposInformer.Run(wait.NeverStop)
        })
    
        return &openpitrixOperator{
            AttachmentInterface:  newAttachmentOperator(s3Client),
        // cachedReposData used
            ApplicationInterface: newApplicationOperator(cachedReposData, ksInformers.KubeSphereSharedInformerFactory(), ksClient, s3Client),
        // cachedReposData used
            RepoInterface:        newRepoOperator(cachedReposData, ksInformers.KubeSphereSharedInformerFactory(), ksClient),
        // cachedReposData used
            ReleaseInterface:     newReleaseOperator(cachedReposData, ksInformers.KubernetesSharedInformerFactory(), ksInformers.KubeSphereSharedInformerFactory(), ksClient),
            CategoryInterface:    newCategoryOperator(ksInformers.KubeSphereSharedInformerFactory(), ksClient),
        }
    }
    

    缓存更新逻辑

    // 缓存结构体
    type cachedRepos struct {
        sync.RWMutex
    
        chartsInRepo  map[workspace]map[string]int
        repoCtgCounts map[string]map[string]int
    
        repos    map[string]*v1alpha1.HelmRepo
        apps     map[string]*v1alpha1.HelmApplication
        versions map[string]*v1alpha1.HelmApplicationVersion
    }
    
    • ByteArrayToSavedIndex:将 repo.Status.Data 转换为 SavedIndex 数组对象
    • 遍历 SavedIndex.Applications
    • 保存(app.ApplicationId:HelmApplication)到 cachedRepos.apps
    func (c *cachedRepos) AddRepo(repo *v1alpha1.HelmRepo) error {
        return c.addRepo(repo, false)
    }
    
    //Add new Repo to cachedRepos
    func (c *cachedRepos) addRepo(repo *v1alpha1.HelmRepo, builtin bool) error {
        if len(repo.Status.Data) == 0 {
            return nil
        }
        index, err := Helmrepoindex.ByteArrayToSavedIndex([]byte(repo.Status.Data))
        if err != nil {
            klog.Errorf("json unmarshal repo %s failed, error: %s", repo.Name, err)
            return err
        }
        ...
    
        chartsCount := 0
        for key, app := range index.Applications {
            if builtin {
                appName = v1alpha1.HelmApplicationIdPrefix + app.Name
            } else {
                appName = app.ApplicationId
            }
    
            HelmApp := v1alpha1.HelmApplication{
            ....
            }
            c.apps[app.ApplicationId] = &HelmApp
    
            var ctg, appVerName string
            var chartData []byte
            for _, ver := range app.Charts {
                chartsCount += 1
                if ver.Annotations != nil && ver.Annotations["category"] != "" {
                    ctg = ver.Annotations["category"]
                }
                if builtin {
                    appVerName = base64.StdEncoding.EncodeToString([]byte(ver.Name + ver.Version))
                    chartData, err = loadBuiltinChartData(ver.Name, ver.Version)
                    if err != nil {
                        return err
                    }
                } else {
                    appVerName = ver.ApplicationVersionId
                }
    
                version := &v1alpha1.HelmApplicationVersion{
                ....
                }
                c.versions[ver.ApplicationVersionId] = version
            }
            ....
        }
        return nil
    }
    

    HelmRepo 协调器

    HelmRepo.Status.Data 加载流程

    1. LoadRepoIndex: convert index.yaml to IndexFile
    2. MergeRepoIndex: merge new and old IndexFile
    3. savedIndex.Bytes(): compress data with zlib.NewWriter
    4. 将 savedIndex 数据存入 CRD(HelmRepo.Status.Data)

    关键结构体

    // HelmRepo.Status.Data == SavedIndex 压缩后的数据
       type SavedIndex struct {
           APIVersion   string                  `json:"apiVersion"`
           Generated    time.Time               `json:"generated"`
           Applications map[string]*Application `json:"apps"`
           PublicKeys   []string                `json:"publicKeys,omitempty"`
    
           // Annotations are additional mappings uninterpreted by Helm. They are made available for
           // other applications to add information to the index file.
           Annotations map[string]string `json:"annotations,omitempty"`
       }
    
       // IndexFile represents the index file in a chart repository
       type IndexFile struct {
           APIVersion string                   `json:"apiVersion"`
           Generated  time.Time                `json:"generated"`
           Entries    map[string]ChartVersions `json:"entries"`
           PublicKeys []string                 `json:"publicKeys,omitempty"`
       }
    

    代码位置

    func (r *ReconcileHelmRepo) syncRepo(instance *v1alpha1.HelmRepo) error {
           // 1. load index from Helm repo
           index, err := Helmrepoindex.LoadRepoIndex(context.TODO(), instance.Spec.Url, &instance.Spec.Credential)
    
           if err != nil {
               klog.Errorf("load index failed, repo: %s, url: %s, err: %s", instance.GetTrueName(), instance.Spec.Url, err)
               return err
           }
    
           existsSavedIndex := &Helmrepoindex.SavedIndex{}
           if len(instance.Status.Data) != 0 {
               existsSavedIndex, err = Helmrepoindex.ByteArrayToSavedIndex([]byte(instance.Status.Data))
               if err != nil {
                   klog.Errorf("json unmarshal failed, repo: %s,  error: %s", instance.GetTrueName(), err)
                   return err
               }
           }
    
           // 2. merge new index with old index which is stored in crd
           savedIndex := Helmrepoindex.MergeRepoIndex(index, existsSavedIndex)
    
           // 3. save index in crd
           data, err := savedIndex.Bytes()
           if err != nil {
               klog.Errorf("json marshal failed, error: %s", err)
               return err
           }
    
           instance.Status.Data = string(data)
           return nil
       }
    

    Question:

    Q1:Helm 仓库发包时如何进行 Helm release 版本控制

    A:修改 Charts.yaml 中的字段 version,然后 Helm package, 等于新增一个 .tgz 包,老版本的不要删除,这时候执行 index 的时候会吧所有的 .tgz 包包含在内。

    $ Helm repo index stable --url=xxx.xx.xx.xxx:8081/
      $ cat index.yaml
      ....
      redis:
      - apiVersion: v1
        appVersion: "1.0"
        created: "2021-06-22T16:34:58.286583012+08:00"
        description: A Helm chart for Kubernetes
        digest: fd7c0d962155330527c0a512a74bea33302fca940b810c43ee5f461b1013dbf5
        name: redis
        urls:
        - xxx.xx.xx.xxx:8081/redis-0.1.1.tgz
        version: 0.1.1
      - apiVersion: v1
        appVersion: "1.0"
        created: "2021-06-22T16:34:58.286109049+08:00"
        description: A Helm chart for Kubernetes
        digest: 1a23bd6d5e45f9d323500bbe170011fb23bfccf2c1bd25814827eb8dc643d7f0
        name: redis
        urls:
        - xxx.xx.xx.xxx:8081/redis-0.1.0.tgz
        version: 0.1.0
    

    Q2:KuberSphere 版本同步功能有缺失?用户添加完 Helm 仓库后,如果有新的应用发布,查询不到

    A:解决方案:使用 3 种同步策略

    • 定时同步 Helm 仓库(HelmRepo 设置一个定时协调的事件)
    • 企业仓库,用户可以设置 hook,发布新版本的时候主动触发更新
    • 用户主动更新 charts

    Q3:index.yaml 缓存位置

    A:某些仓库的index.yaml 比较大,如果1000个用户,1000个charts 会太吃内存。建议常用index.yaml的放在内存中,不常用的index.yaml存储在本地磁盘。

    本文由博客一文多发平台 OpenWrite 发布!

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  • 原文地址:https://www.cnblogs.com/kubesphere/p/14931543.html
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