Use the Join of Dir and File name instead of DefaultKubeConfig

cmd/kubeadm/app/cmd/config.go

@@ -21,6 +21,7 @@ import (
 	"fmt"
 	"io"
 	"io/ioutil"
+	"path/filepath"
 	"strings"
 
 	"github.com/golang/glog"
@@ -80,7 +81,7 @@ func NewCmdConfig(out io.Writer) *cobra.Command {
 		RunE: cmdutil.SubCmdRunE("config"),
 	}
 
-	cmd.PersistentFlags().StringVar(&kubeConfigFile, "kubeconfig", kubeadmconstants.DefaultKubeConfig, "The KubeConfig file to use when talking to the cluster.")
+	cmd.PersistentFlags().StringVar(&kubeConfigFile, "kubeconfig", filepath.Join(kubeadmconstants.KubernetesDir, kubeadmconstants.AdminKubeConfigFileName), "The KubeConfig file to use when talking to the cluster.")
 
 	cmd.AddCommand(NewCmdConfigPrintDefault(out))
 	cmd.AddCommand(NewCmdConfigMigrate(out))

cmd/kubeadm/app/cmd/phases/addons.go

@@ -17,6 +17,7 @@ limitations under the License.
 package phases
 
 import (
+	"path/filepath"
 	"strings"
 
 	"github.com/golang/glog"
@@ -141,7 +142,7 @@ func getAddonsSubCommands() []*cobra.Command {
 		}
 
 		// Add flags to the command
-		cmd.Flags().StringVar(&kubeConfigFile, "kubeconfig", kubeadmconstants.DefaultKubeConfig, "The KubeConfig file to use when talking to the cluster")
+		cmd.Flags().StringVar(&kubeConfigFile, "kubeconfig", filepath.Join(kubeadmconstants.KubernetesDir, kubeadmconstants.AdminKubeConfigFileName), "The KubeConfig file to use when talking to the cluster")
 		cmd.Flags().StringVar(&cfgPath, "config", cfgPath, "Path to a kubeadm config file. WARNING: Usage of a configuration file is experimental")
 		cmd.Flags().StringVar(&cfg.KubernetesVersion, "kubernetes-version", cfg.KubernetesVersion, `Choose a specific Kubernetes version for the control plane`)
 		cmd.Flags().StringVar(&cfg.ImageRepository, "image-repository", cfg.ImageRepository, `Choose a container registry to pull control plane images from`)

cmd/kubeadm/app/cmd/phases/bootstraptoken.go

@@ -18,6 +18,7 @@ package phases
 
 import (
 	"fmt"
+	"path/filepath"
 
 	"github.com/golang/glog"
 	"github.com/spf13/cobra"
@@ -95,7 +96,7 @@ func NewCmdBootstrapToken() *cobra.Command {
 		Aliases: []string{"bootstraptoken"},
 	}
 
-	cmd.PersistentFlags().StringVar(&kubeConfigFile, "kubeconfig", kubeadmconstants.DefaultKubeConfig, "The KubeConfig file to use when talking to the cluster")
+	cmd.PersistentFlags().StringVar(&kubeConfigFile, "kubeconfig", filepath.Join(kubeadmconstants.KubernetesDir, kubeadmconstants.AdminKubeConfigFileName), "The KubeConfig file to use when talking to the cluster")
 
 	// Add subcommands
 	cmd.AddCommand(NewSubCmdBootstrapTokenAll(&kubeConfigFile))

cmd/kubeadm/app/cmd/phases/markmaster.go

@@ -17,6 +17,8 @@ limitations under the License.
 package phases
 
 import (
+	"path/filepath"
+
 	"github.com/spf13/cobra"
 
 	kubeadmscheme "k8s.io/kubernetes/cmd/kubeadm/app/apis/kubeadm/scheme"
@@ -81,7 +83,7 @@ func NewCmdMarkMaster() *cobra.Command {
 		},
 	}
 
-	cmd.Flags().StringVar(&kubeConfigFile, "kubeconfig", kubeadmconstants.DefaultKubeConfig, "The KubeConfig file to use when talking to the cluster")
+	cmd.Flags().StringVar(&kubeConfigFile, "kubeconfig", filepath.Join(kubeadmconstants.KubernetesDir, kubeadmconstants.AdminKubeConfigFileName), "The KubeConfig file to use when talking to the cluster")
 	cmd.Flags().StringVar(&cfgPath, "config", cfgPath, "Path to kubeadm config file. WARNING: Usage of a configuration file is experimental")
 	cmd.Flags().StringVar(&cfg.NodeRegistration.Name, "node-name", cfg.NodeRegistration.Name, `The node name to which label and taints should apply`)
 

cmd/kubeadm/app/cmd/phases/selfhosting.go

@@ -18,6 +18,7 @@ package phases
 
 import (
 	"os"
+	"path/filepath"
 	"strings"
 	"time"
 
@@ -123,7 +124,7 @@ func getSelfhostingSubCommand() *cobra.Command {
 
 	// flags that are not bound to the configuration object
 	// Note: All flags that are not bound to the cfg object should be whitelisted in cmd/kubeadm/app/apis/kubeadm/validation/validation.go
-	cmd.Flags().StringVar(&kubeConfigFile, "kubeconfig", kubeadmconstants.DefaultKubeConfig, "The KubeConfig file to use when talking to the cluster")
+	cmd.Flags().StringVar(&kubeConfigFile, "kubeconfig", filepath.Join(kubeadmconstants.KubernetesDir, kubeadmconstants.AdminKubeConfigFileName), "The KubeConfig file to use when talking to the cluster")
 
 	return cmd
 }

cmd/kubeadm/app/cmd/phases/uploadconfig.go

@@ -18,6 +18,7 @@ package phases
 
 import (
 	"fmt"
+	"path/filepath"
 
 	"github.com/spf13/cobra"
 
@@ -77,7 +78,7 @@ func NewCmdUploadConfig() *cobra.Command {
 		},
 	}
 
-	cmd.Flags().StringVar(&kubeConfigFile, "kubeconfig", kubeadmconstants.DefaultKubeConfig, "The KubeConfig file to use when talking to the cluster")
+	cmd.Flags().StringVar(&kubeConfigFile, "kubeconfig", filepath.Join(kubeadmconstants.KubernetesDir, kubeadmconstants.AdminKubeConfigFileName), "The KubeConfig file to use when talking to the cluster")
 	cmd.Flags().StringVar(&cfgPath, "config", "", "Path to a kubeadm config file. WARNING: Usage of a configuration file is experimental")
 
 	return cmd

cmd/kubeadm/app/cmd/token.go

@@ -20,6 +20,7 @@ import (
 	"fmt"
 	"io"
 	"os"
+	"path/filepath"
 	"strings"
 	"text/tabwriter"
 	"time"
@@ -34,7 +35,6 @@ import (
 	clientset "k8s.io/client-go/kubernetes"
 	bootstrapapi "k8s.io/client-go/tools/bootstrap/token/api"
 	bootstraputil "k8s.io/client-go/tools/bootstrap/token/util"
-	"k8s.io/client-go/tools/clientcmd"
 	kubeadmapi "k8s.io/kubernetes/cmd/kubeadm/app/apis/kubeadm"
 	kubeadmscheme "k8s.io/kubernetes/cmd/kubeadm/app/apis/kubeadm/scheme"
 	kubeadmapiv1alpha3 "k8s.io/kubernetes/cmd/kubeadm/app/apis/kubeadm/v1alpha3"
@@ -85,7 +85,7 @@ func NewCmdToken(out io.Writer, errW io.Writer) *cobra.Command {
 	}
 
 	tokenCmd.PersistentFlags().StringVar(&kubeConfigFile,
-		"kubeconfig", kubeadmconstants.DefaultKubeConfig, "The KubeConfig file to use when talking to the cluster. If the flag is not set a set of standard locations are searched for an existing KubeConfig file")
+		"kubeconfig", filepath.Join(kubeadmconstants.KubernetesDir, kubeadmconstants.AdminKubeConfigFileName), "The KubeConfig file to use when talking to the cluster. If the flag is not set a set of standard locations are searched for an existing KubeConfig file")
 	tokenCmd.PersistentFlags().BoolVar(&dryRun,
 		"dry-run", dryRun, "Whether to enable dry-run mode or not")
 
@@ -122,7 +122,7 @@ func NewCmdToken(out io.Writer, errW io.Writer) *cobra.Command {
 			kubeadmutil.CheckErr(err)
 
 			glog.V(1).Infoln("[token] getting Clientsets from KubeConfig file")
-			kubeConfigFile = findExistingKubeConfig(kubeConfigFile)
+			kubeConfigFile = cmdutil.FindExistingKubeConfig(kubeConfigFile)
 			client, err := getClientset(kubeConfigFile, dryRun)
 			kubeadmutil.CheckErr(err)
 
@@ -149,7 +149,7 @@ func NewCmdToken(out io.Writer, errW io.Writer) *cobra.Command {
 			This command will list all bootstrap tokens for you.
 		`),
 		Run: func(tokenCmd *cobra.Command, args []string) {
-			kubeConfigFile = findExistingKubeConfig(kubeConfigFile)
+			kubeConfigFile = cmdutil.FindExistingKubeConfig(kubeConfigFile)
 			client, err := getClientset(kubeConfigFile, dryRun)
 			kubeadmutil.CheckErr(err)
 
@@ -173,7 +173,7 @@ func NewCmdToken(out io.Writer, errW io.Writer) *cobra.Command {
 			if len(args) < 1 {
 				kubeadmutil.CheckErr(fmt.Errorf("missing subcommand; 'token delete' is missing token of form %q", bootstrapapi.BootstrapTokenIDPattern))
 			}
-			kubeConfigFile = findExistingKubeConfig(kubeConfigFile)
+			kubeConfigFile = cmdutil.FindExistingKubeConfig(kubeConfigFile)
 			client, err := getClientset(kubeConfigFile, dryRun)
 			kubeadmutil.CheckErr(err)
 
@@ -356,16 +356,3 @@ func getClientset(file string, dryRun bool) (clientset.Interface, error) {
 	}
 	return kubeconfigutil.ClientSetFromFile(file)
 }
-
-func findExistingKubeConfig(file string) string {
-	// The user did provide a --kubeconfig flag. Respect that and threat it as an
-	// explicit path without building a DefaultClientConfigLoadingRules object.
-	if file != kubeadmconstants.DefaultKubeConfig {
-		return file
-	}
-	// The user did not provide a --kubeconfig flag. Find a config in the standard
-	// locations using DefaultClientConfigLoadingRules, but also consider `defaultKubeConfig`.
-	rules := clientcmd.NewDefaultClientConfigLoadingRules()
-	rules.Precedence = append(rules.Precedence, kubeadmconstants.DefaultKubeConfig)
-	return rules.GetDefaultFilename()
-}

cmd/kubeadm/app/cmd/upgrade/upgrade.go

@@ -18,6 +18,7 @@ package upgrade
 
 import (
 	"io"
+	"path/filepath"
 	"strings"
 
 	"github.com/spf13/cobra"
@@ -46,7 +47,7 @@ type applyPlanFlags struct {
 // NewCmdUpgrade returns the cobra command for `kubeadm upgrade`
 func NewCmdUpgrade(out io.Writer) *cobra.Command {
 	flags := &applyPlanFlags{
-		kubeConfigPath:            kubeadmconstants.DefaultKubeConfig,
+		kubeConfigPath:            filepath.Join(kubeadmconstants.KubernetesDir, kubeadmconstants.AdminKubeConfigFileName),
 		cfgPath:                   "",
 		featureGatesString:        "",
 		allowExperimentalUpgrades: false,

cmd/kubeadm/app/cmd/util/BUILD

@@ -10,6 +10,7 @@ go_library(
     importpath = "k8s.io/kubernetes/cmd/kubeadm/app/cmd/util",
     visibility = ["//visibility:public"],
     deps = [
+        "//cmd/kubeadm/app/constants:go_default_library",
         "//cmd/kubeadm/app/util/kubeconfig:go_default_library",
         "//cmd/kubeadm/app/util/pubkeypin:go_default_library",
         "//pkg/util/normalizer:go_default_library",

cmd/kubeadm/app/cmd/util/cmdutil.go

@@ -18,8 +18,11 @@ package util
 
 import (
 	"fmt"
+	"path/filepath"
 
 	"github.com/spf13/cobra"
+	"k8s.io/client-go/tools/clientcmd"
+	kubeadmconstants "k8s.io/kubernetes/cmd/kubeadm/app/constants"
 )
 
 // SubCmdRunE returns a function that handles a case where a subcommand must be specified
@@ -57,3 +60,17 @@ func ValidateExactArgNumber(args []string, supportedArgs []string) error {
 	}
 	return nil
 }
+
+// FindExistingKubeConfig returns the localtion of kubeconfig
+func FindExistingKubeConfig(file string) string {
+	// The user did provide a --kubeconfig flag. Respect that and threat it as an
+	// explicit path without building a DefaultClientConfigLoadingRules object.
+	if file != filepath.Join(kubeadmconstants.KubernetesDir, kubeadmconstants.AdminKubeConfigFileName) {
+		return file
+	}
+	// The user did not provide a --kubeconfig flag. Find a config in the standard
+	// locations using DefaultClientConfigLoadingRules, but also consider `defaultKubeConfig`.
+	rules := clientcmd.NewDefaultClientConfigLoadingRules()
+	rules.Precedence = append(rules.Precedence, filepath.Join(kubeadmconstants.KubernetesDir, kubeadmconstants.AdminKubeConfigFileName))
+	return rules.GetDefaultFilename()
+}

cmd/kubeadm/app/constants/constants.go

@@ -302,9 +302,6 @@ const (
 	// YAMLDocumentSeparator is the separator for YAML documents
 	// TODO: Find a better place for this constant
 	YAMLDocumentSeparator = "---\n"
-
-	// DefaultKubeConfig is the default localtion of KubeConfig
-	DefaultKubeConfig = "/etc/kubernetes/admin.conf"
 )
 
 var (

cmd/kubeadm/app/constants/constants_test.go

@@ -18,6 +18,7 @@ package constants
 
 import (
 	"fmt"
+	"path/filepath"
 	"strings"
 	"testing"
 
@@ -38,7 +39,7 @@ func TestGetStaticPodDirectory(t *testing.T) {
 }
 
 func TestGetAdminKubeConfigPath(t *testing.T) {
-	expected := DefaultKubeConfig
+	expected := filepath.Join(KubernetesDir, AdminKubeConfigFileName)
 	actual := GetAdminKubeConfigPath()
 
 	if actual != expected {