Merge pull request #34834 from apprenda/kubeadm_fix_preflight

Automatic merge from submit-queue

kubeadm: fix preflight checks

This PR fixes a couple issues cause by some bad rebases:
* When a pre-flight check returned errors, `kubeadm` would exit with error code `1` instead of `2` as the original pre-flight PR meant. This would also cause the output of `kubeadm` to include some stuff that was not supposed to be there.
* Duplicated `k8s.io/kubernetes/cmd/kubeadm/app/util` import.

I also took the freedom to do some output clean-up based on the input from the original pre-flight PR.

/cc @dmmcquay @dgoodwin @luxas

cmd/kubeadm/app/cmd/init.go

@@ -27,7 +27,6 @@ import (
 	kubeadmapi "k8s.io/kubernetes/cmd/kubeadm/app/apis/kubeadm"
 	kubemaster "k8s.io/kubernetes/cmd/kubeadm/app/master"
 	"k8s.io/kubernetes/cmd/kubeadm/app/preflight"
-	cmdutil "k8s.io/kubernetes/cmd/kubeadm/app/util"
 	kubeadmutil "k8s.io/kubernetes/cmd/kubeadm/app/util"
 	"k8s.io/kubernetes/pkg/api"
 	"k8s.io/kubernetes/pkg/cloudprovider"
@@ -55,14 +54,9 @@ func NewCmdInit(out io.Writer) *cobra.Command {
 		Use:   "init",
 		Short: "Run this in order to set up the Kubernetes master.",
 		Run: func(cmd *cobra.Command, args []string) {
-			check := func(err error) {
-				if err != nil {
-					cmdutil.CheckErr(fmt.Errorf("<cmd/init> %v", err))
-				}
-			}
 			i, err := NewInit(cfgPath, cfg, skipPreFlight)
-			check(err)
-			check(i.Run(out))
+			kubeadmutil.CheckErr(err)
+			kubeadmutil.CheckErr(i.Run(out))
 		},
 	}
 
@@ -126,6 +120,7 @@ func NewCmdInit(out io.Writer) *cobra.Command {
 		"etcd client key file. Note: The path must be in /etc/ssl/certs",
 	)
 	cmd.PersistentFlags().MarkDeprecated("external-etcd-keyfile", "this flag will be removed when componentconfig exists")
+
 	cmd.PersistentFlags().BoolVar(
 		&skipPreFlight, "skip-preflight-checks", false,
 		"skip preflight checks normally run before modifying the system",
@@ -150,10 +145,10 @@ func NewInit(cfgPath string, cfg *kubeadmapi.MasterConfiguration, skipPreFlight
 	}
 
 	if !skipPreFlight {
-		fmt.Println("<cmd/init> Running pre-flight checks")
+		fmt.Println("Running pre-flight checks")
 		err := preflight.RunInitMasterChecks()
 		if err != nil {
-			return nil, err
+			return nil, &preflight.PreFlightError{Msg: err.Error()}
 		}
 	} else {
 		fmt.Println("Skipping pre-flight checks")
@@ -180,9 +175,8 @@ func NewInit(cfgPath string, cfg *kubeadmapi.MasterConfiguration, skipPreFlight
 	return &Init{cfg: cfg}, nil
 }
 
-// RunInit executes master node provisioning, including certificates, needed static pod manifests, etc.
+// Run executes master node provisioning, including certificates, needed static pod manifests, etc.
 func (i *Init) Run(out io.Writer) error {
-
 	if err := kubemaster.CreateTokenAuthFile(&i.cfg.Secrets); err != nil {
 		return err
 	}

cmd/kubeadm/app/cmd/join.go

@@ -73,7 +73,7 @@ func RunJoin(out io.Writer, cmd *cobra.Command, args []string, s *kubeadmapi.Nod
 		fmt.Println("Running pre-flight checks")
 		err := preflight.RunJoinNodeChecks()
 		if err != nil {
-			return err
+			return &preflight.PreFlightError{Msg: err.Error()}
 		}
 	} else {
 		fmt.Println("Skipping pre-flight checks")

cmd/kubeadm/app/preflight/checks.go

@@ -17,6 +17,7 @@ limitations under the License.
 package preflight
 
 import (
+	"errors"
 	"fmt"
 	"io"
 	"net"
@@ -27,12 +28,11 @@ import (
 )
 
 type PreFlightError struct {
-	Msg   string
-	Count int
+	Msg string
 }
 
 func (e *PreFlightError) Error() string {
-	return fmt.Sprintf("preflight check error\n  count: %d \n  msg: %s", e.Count, e.Msg)
+	return fmt.Sprintf("preflight check errors:\n%s", e.Msg)
 }
 
 // PreFlightCheck validates the state of the system to ensure kubeadm will be
@@ -216,23 +216,20 @@ func RunJoinNodeChecks() error {
 func runChecks(checks []PreFlightCheck) error {
 	found := []error{}
 	for _, c := range checks {
-		warnings, errors := c.Check()
+		warnings, errs := c.Check()
 		for _, w := range warnings {
-			fmt.Printf("<preflight/checks> WARNING: %s\n", w)
+			fmt.Printf("WARNING: %s\n", w)
 		}
-		for _, e := range errors {
+		for _, e := range errs {
 			found = append(found, e)
 		}
 	}
 	if len(found) > 0 {
-		errors := "\n"
+		errs := ""
 		for _, i := range found {
-			errors += "\t" + i.Error() + "\n"
-		}
-		return &PreFlightError{
-			Msg:   errors,
-			Count: len(found),
+			errs += "\t" + i.Error() + "\n"
 		}
+		return errors.New(errs)
 	}
 	return nil
 }