Improve the kubeadm reset command. Reorder the functions and log more user-friendly output

cmd/kubeadm/app/cmd/reset.go

 /*
-Copyright 2014 The Kubernetes Authors.
+Copyright 2016 The Kubernetes Authors.
 
 Licensed under the Apache License, Version 2.0 (the "License");
 you may not use this file except in compliance with the License.
@@ -21,16 +21,17 @@ import (
 	"io"
 	"os"
 	"os/exec"
-	"path/filepath"
+	"path"
 
 	"github.com/spf13/cobra"
 
+	kubeadmapi "k8s.io/kubernetes/cmd/kubeadm/app/apis/kubeadm"
 	"k8s.io/kubernetes/cmd/kubeadm/app/preflight"
 	kubeadmutil "k8s.io/kubernetes/cmd/kubeadm/app/util"
 	"k8s.io/kubernetes/pkg/util/initsystem"
 )
 
-// NewCmdReset returns "kubeadm reset" command.
+// NewCmdReset returns the "kubeadm reset" command
 func NewCmdReset(out io.Writer) *cobra.Command {
 	var skipPreFlight bool
 	cmd := &cobra.Command{
@@ -55,111 +56,118 @@ type Reset struct{}
 
 func NewReset(skipPreFlight bool) (*Reset, error) {
 	if !skipPreFlight {
-		fmt.Println("Running pre-flight checks")
-		err := preflight.RunResetCheck()
-		if err != nil {
+		fmt.Println("[preflight] Running pre-flight checks...")
+
+		if err := preflight.RunResetCheck(); err != nil {
 			return nil, &preflight.PreFlightError{Msg: err.Error()}
 		}
 	} else {
-		fmt.Println("Skipping pre-flight checks")
+		fmt.Println("[preflight] Skipping pre-flight checks...")
 	}
 
 	return &Reset{}, nil
 }
 
-// cleanDir removes everything in a directory, but not the directory itself:
-func cleanDir(path string) {
-	// If the directory doesn't even exist there's nothing to do, and we do
-	// not consider this an error:
-	if _, err := os.Stat(path); os.IsNotExist(err) {
-		return
-	}
-
-	d, err := os.Open(path)
-	if err != nil {
-		fmt.Printf("failed to remove directory: [%v]\n", err)
-	}
-	defer d.Close()
-	names, err := d.Readdirnames(-1)
-	if err != nil {
-		fmt.Printf("failed to remove directory: [%v]\n", err)
-	}
-	for _, name := range names {
-		err = os.RemoveAll(filepath.Join(path, name))
-		if err != nil {
-			fmt.Printf("failed to remove directory: [%v]\n", err)
-		}
-	}
-}
-
-// resetConfigDir is used to cleanup the files kubeadm writes in /etc/kubernetes/.
-func resetConfigDir(configDirPath string) {
-	dirsToClean := []string{
-		filepath.Join(configDirPath, "manifests"),
-		filepath.Join(configDirPath, "pki"),
-	}
-	fmt.Printf("Deleting contents of config directories: %v\n", dirsToClean)
-	for _, dir := range dirsToClean {
-		cleanDir(dir)
-	}
-
-	filesToClean := []string{
-		filepath.Join(configDirPath, "admin.conf"),
-		filepath.Join(configDirPath, "kubelet.conf"),
-	}
-	fmt.Printf("Deleting files: %v\n", filesToClean)
-	for _, path := range filesToClean {
-		err := os.RemoveAll(path)
-		if err != nil {
-			fmt.Printf("failed to remove file: [%v]\n", err)
-		}
-	}
-}
-
 // Run reverts any changes made to this host by "kubeadm init" or "kubeadm join".
 func (r *Reset) Run(out io.Writer) error {
 	serviceToStop := "kubelet"
 	initSystem, err := initsystem.GetInitSystem()
 	if err != nil {
-		fmt.Printf("%v", err)
+		fmt.Printf("[reset] Failed to detect init system and stop the kubelet service: %v\n", err)
 	} else {
-		fmt.Printf("Stopping the %s service...\n", serviceToStop)
+		fmt.Printf("[reset] Stopping the %s service...\n", serviceToStop)
 		if err := initSystem.ServiceStop(serviceToStop); err != nil {
-			fmt.Printf("failed to stop the %s service", serviceToStop)
+			fmt.Printf("[reset] Failed to stop the %s service", serviceToStop)
 		}
 	}
 
-	fmt.Printf("Unmounting directories in /var/lib/kubelet...\n")
+	fmt.Println("[reset] Unmounting directories in /var/lib/kubelet...")
 	umountDirsCmd := "cat /proc/mounts | awk '{print $2}' | grep '/var/lib/kubelet' | xargs -r umount"
 	umountOutputBytes, err := exec.Command("sh", "-c", umountDirsCmd).Output()
 	if err != nil {
-		fmt.Printf("failed to unmount directories in /var/lib/kubelet, %s", string(umountOutputBytes))
+		fmt.Printf("[reset] Failed to unmount directories in /var/lib/kubelet: %s\n", string(umountOutputBytes))
 	}
 
+	// Remove contents from the config and pki directories
+	resetConfigDir(kubeadmapi.GlobalEnvParams.KubernetesDir, kubeadmapi.GlobalEnvParams.HostPKIPath)
+
 	dirsToClean := []string{"/var/lib/kubelet", "/etc/cni/net.d"}
 
 	// Only clear etcd data when the etcd manifest is found. In case it is not found, we must assume that the user
 	// provided external etcd endpoints. In that case, it is his own responsibility to reset etcd
 	if _, err := os.Stat("/etc/kubernetes/manifests/etcd.json"); os.IsNotExist(err) {
 		dirsToClean = append(dirsToClean, "/var/lib/etcd")
+	} else {
+		fmt.Println("[reset] No etcd manifest found in %q, assuming external etcd.", "/etc/kubernetes/manifests/etcd.json")
 	}
 
-	resetConfigDir("/etc/kubernetes/")
-
-	fmt.Printf("Deleting contents of stateful directories: %v\n", dirsToClean)
+	fmt.Printf("[reset] Deleting contents of stateful directories: %v\n", dirsToClean)
 	for _, dir := range dirsToClean {
 		cleanDir(dir)
 	}
 
 	dockerCheck := preflight.ServiceCheck{Service: "docker"}
 	if warnings, errors := dockerCheck.Check(); len(warnings) == 0 && len(errors) == 0 {
-		fmt.Println("Stopping all running docker containers...")
-		if err := exec.Command("sh", "-c", "docker ps | grep 'k8s_' | awk '{print $1}' | xargs docker rm --force --volumes").Run(); err != nil {
-			fmt.Println("failed to stop the running containers")
+		fmt.Println("[reset] Stopping all running docker containers...")
+		if err := exec.Command("sh", "-c", "docker ps | grep 'k8s_' | awk '{print $1}' | xargs -r docker rm --force --volumes").Run(); err != nil {
+			fmt.Println("[reset] Failed to stop the running containers")
 		}
 	} else {
-		fmt.Println("docker doesn't seem to be running, skipping the removal of kubernetes containers")
+		fmt.Println("[reset] docker doesn't seem to be running, skipping the removal of running kubernetes containers")
 	}
 
 	return nil
 }
+
+// cleanDir removes everything in a directory, but not the directory itself
+func cleanDir(filepath string) error {
+	// If the directory doesn't even exist there's nothing to do, and we do
+	// not consider this an error
+	if _, err := os.Stat(filepath); os.IsNotExist(err) {
+		return nil
+	}
+
+	d, err := os.Open(filepath)
+	if err != nil {
+		return err
+	}
+	defer d.Close()
+	names, err := d.Readdirnames(-1)
+	if err != nil {
+		return err
+	}
+	for _, name := range names {
+		err = os.RemoveAll(path.Join(filepath, name))
+		if err != nil {
+			return err
+		}
+	}
+	return nil
+}
+
+// resetConfigDir is used to cleanup the files kubeadm writes in /etc/kubernetes/.
+func resetConfigDir(configPathDir, pkiPathDir string) {
+	dirsToClean := []string{
+		path.Join(configPathDir, "manifests"),
+		pkiPathDir,
+	}
+	fmt.Printf("[reset] Deleting contents of config directories: %v\n", dirsToClean)
+	for _, dir := range dirsToClean {
+		err := cleanDir(dir)
+		if err != nil {
+			fmt.Printf("[reset] Failed to remove directory: %q [%v]", dir, err)
+		}
+	}
+
+	filesToClean := []string{
+		path.Join(configPathDir, "admin.conf"),
+		path.Join(configPathDir, "kubelet.conf"),
+	}
+	fmt.Printf("[reset] Deleting files: %v\n", filesToClean)
+	for _, path := range filesToClean {
+		err := os.RemoveAll(path)
+		if err != nil {
+			fmt.Printf("[reset] Failed to remove file: %q [%v]\n", path, err)
+		}
+	}
+}

cmd/kubeadm/app/cmd/reset_test.go

@@ -162,7 +162,7 @@ func TestConfigDirCleaner(t *testing.T) {
 			}
 		}
 
-		resetConfigDir(tmpDir)
+		resetConfigDir(tmpDir, filepath.Join(tmpDir, "pki"))
 
 		// Verify the files we cleanup implicitly in every test:
 		assertExists(t, tmpDir)