kubeadm: reduce the number of fetch configuration when reset

cmd/kubeadm/app/cmd/BUILD

@@ -84,6 +84,7 @@ go_test(
     ],
     embed = [":go_default_library"],
     deps = [
+        "//cmd/kubeadm/app/apis/kubeadm:go_default_library",
         "//cmd/kubeadm/app/apis/kubeadm/v1beta1:go_default_library",
         "//cmd/kubeadm/app/apis/kubeadm/validation:go_default_library",
         "//cmd/kubeadm/app/cmd/options:go_default_library",

cmd/kubeadm/app/cmd/reset.go

@@ -31,6 +31,7 @@ import (
 	"k8s.io/apimachinery/pkg/util/sets"
 	clientset "k8s.io/client-go/kubernetes"
 	"k8s.io/klog"
+	kubeadmapi "k8s.io/kubernetes/cmd/kubeadm/app/apis/kubeadm"
 	kubeadmapiv1beta1 "k8s.io/kubernetes/cmd/kubeadm/app/apis/kubeadm/v1beta1"
 	"k8s.io/kubernetes/cmd/kubeadm/app/apis/kubeadm/validation"
 	"k8s.io/kubernetes/cmd/kubeadm/app/cmd/options"
@@ -68,15 +69,20 @@ func NewCmdReset(in io.Reader, out io.Writer) *cobra.Command {
 				kubeadmutil.CheckErr(err)
 			}
 
+			cfg, err := configutil.FetchInitConfigurationFromCluster(client, os.Stdout, "reset", false)
+			if err != nil {
+				klog.Warningf("[reset] Unable to fetch the kubeadm-config ConfigMap from cluster: %v", err)
+			}
+
 			if criSocketPath == "" {
-				criSocketPath, err = resetDetectCRISocket(client)
+				criSocketPath, err = resetDetectCRISocket(cfg)
 				kubeadmutil.CheckErr(err)
 				klog.V(1).Infof("[reset] detected and using CRI socket: %s", criSocketPath)
 			}
 
 			r, err := NewReset(in, ignorePreflightErrorsSet, forceReset, certsDir, criSocketPath)
 			kubeadmutil.CheckErr(err)
-			kubeadmutil.CheckErr(r.Run(out, client))
+			kubeadmutil.CheckErr(r.Run(out, client, cfg))
 		},
 	}
 
@@ -131,18 +137,20 @@ func NewReset(in io.Reader, ignorePreflightErrors sets.String, forceReset bool,
 }
 
 // Run reverts any changes made to this host by "kubeadm init" or "kubeadm join".
-func (r *Reset) Run(out io.Writer, client clientset.Interface) error {
+func (r *Reset) Run(out io.Writer, client clientset.Interface, cfg *kubeadmapi.InitConfiguration) error {
 	var dirsToClean []string
 	// Only clear etcd data when using local etcd.
 	etcdManifestPath := filepath.Join(kubeadmconstants.KubernetesDir, kubeadmconstants.ManifestsSubDirName, "etcd.yaml")
 
 	klog.V(1).Infof("[reset] checking for etcd config")
-	etcdDataDir, err := getEtcdDataDir(etcdManifestPath, client)
+	etcdDataDir, err := getEtcdDataDir(etcdManifestPath, cfg)
 	if err == nil {
 		dirsToClean = append(dirsToClean, etcdDataDir)
-		if err := removeEtcdMember(client); err != nil {
+		if cfg != nil {
+			if err := etcdphase.RemoveStackedEtcdMemberFromCluster(client, cfg); err != nil {
 				klog.Warningf("[reset] failed to remove etcd member: %v\n.Please manually remove this etcd member using etcdctl", err)
 			}
+		}
 	} else {
 		fmt.Println("[reset] no etcd config found. Assuming external etcd")
 		fmt.Println("[reset] please manually reset etcd to prevent further issues")
@@ -209,25 +217,14 @@ func (r *Reset) Run(out io.Writer, client clientset.Interface) error {
 	return nil
 }
 
-func removeEtcdMember(client clientset.Interface) error {
-	cfg, err := configutil.FetchInitConfigurationFromCluster(client, os.Stdout, "reset", false)
-	if err != nil {
-		return err
-	}
-	return etcdphase.RemoveStackedEtcdMemberFromCluster(client, cfg)
-}
-
-func getEtcdDataDir(manifestPath string, client clientset.Interface) (string, error) {
+func getEtcdDataDir(manifestPath string, cfg *kubeadmapi.InitConfiguration) (string, error) {
 	const etcdVolumeName = "etcd-data"
 	var dataDir string
 
-	if client != nil {
-		cfg, err := configutil.FetchInitConfigurationFromCluster(client, os.Stdout, "reset", false)
-		if err == nil && cfg.Etcd.Local != nil {
+	if cfg != nil && cfg.Etcd.Local != nil {
 		return cfg.Etcd.Local.DataDir, nil
 	}
-		klog.Warningf("[reset] Unable to fetch the kubeadm-config ConfigMap, using etcd pod spec as fallback: %v", err)
-	}
+	klog.Warningln("[reset] No kubeadm config, using etcd pod spec to get data directory")
 
 	etcdPod, err := utilstaticpod.ReadStaticPodFromDisk(manifestPath)
 	if err != nil {
@@ -311,14 +308,11 @@ func resetConfigDir(configPathDir, pkiPathDir string) {
 	}
 }
 
-func resetDetectCRISocket(client clientset.Interface) (string, error) {
-	if client != nil {
-		// first try to connect to the cluster for the CRI socket
-		cfg, err := configutil.FetchInitConfigurationFromCluster(client, os.Stdout, "reset", false)
-		if err == nil {
+func resetDetectCRISocket(cfg *kubeadmapi.InitConfiguration) (string, error) {
+	if cfg != nil {
+		// first try to get the CRI socket from the cluster configuration
 		return cfg.NodeRegistration.CRISocket, nil
 	}
-	}
 
 	// if this fails, try to detect it
 	return utilruntime.DetectCRISocket()

cmd/kubeadm/app/cmd/reset_test.go

@@ -25,7 +25,7 @@ import (
 
 	"github.com/lithammer/dedent"
 
-	clientsetfake "k8s.io/client-go/kubernetes/fake"
+	kubeadmapi "k8s.io/kubernetes/cmd/kubeadm/app/apis/kubeadm"
 	kubeadmapiv1beta1 "k8s.io/kubernetes/cmd/kubeadm/app/apis/kubeadm/v1beta1"
 	"k8s.io/kubernetes/cmd/kubeadm/app/apis/kubeadm/validation"
 	kubeadmconstants "k8s.io/kubernetes/cmd/kubeadm/app/constants"
@@ -275,38 +275,38 @@ func TestGetEtcdDataDir(t *testing.T) {
 		podYaml       string
 		expectErr     bool
 		writeManifest bool
-		validClient   bool
+		validConfig   bool
 	}{
 		"non-existent file returns error": {
 			expectErr:     true,
 			writeManifest: false,
-			validClient:   true,
+			validConfig:   true,
 		},
 		"return etcd data dir": {
 			dataDir:       "/path/to/etcd",
 			podYaml:       etcdPod,
 			expectErr:     false,
 			writeManifest: true,
-			validClient:   true,
+			validConfig:   true,
 		},
 		"invalid etcd pod": {
 			podYaml:       etcdPodInvalid,
 			expectErr:     true,
 			writeManifest: true,
-			validClient:   true,
+			validConfig:   true,
 		},
 		"etcd pod spec without data volume": {
 			podYaml:       etcdPodWithoutDataVolume,
 			expectErr:     true,
 			writeManifest: true,
-			validClient:   true,
+			validConfig:   true,
 		},
 		"kubeconfig file doesn't exist": {
 			dataDir:       "/path/to/etcd",
 			podYaml:       etcdPod,
 			expectErr:     false,
 			writeManifest: true,
-			validClient:   false,
+			validConfig:   false,
 		},
 	}
 
@@ -325,9 +325,9 @@ func TestGetEtcdDataDir(t *testing.T) {
 
 			var dataDir string
 			var err error
-			if test.validClient {
-				client := clientsetfake.NewSimpleClientset()
-				dataDir, err = getEtcdDataDir(manifestPath, client)
+			if test.validConfig {
+				cfg := &kubeadmapi.InitConfiguration{}
+				dataDir, err = getEtcdDataDir(manifestPath, cfg)
 			} else {
 				dataDir, err = getEtcdDataDir(manifestPath, nil)
 			}