Merge pull request #78033 from rajansandeep/corednsmigration

Add the ability to migrate CoreDNS configmap in kubeadm

Godeps/LICENSES

@@ -4231,6 +4231,215 @@ SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 ================================================================================
 
 
+================================================================================
+= vendor/github.com/coredns/corefile-migration licensed under: =
+
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+= vendor/github.com/coredns/corefile-migration/LICENSE 86d3f3a95c324c9479bd8986968f4327
+================================================================================
+
+
 ================================================================================
 = vendor/github.com/coreos/bbolt licensed under: =
 

build/dependencies.yaml

@@ -73,7 +73,7 @@ dependencies:
       match: k8s.gcr.io/coredns
 
   - name: "coredns-kubeadm"
-    version: 1.3.1
+    version: 1.5.0
     refPaths:
     - path: cmd/kubeadm/app/constants/constants.go
       match: CoreDNSVersion =

cmd/kubeadm/.import-restrictions

@@ -101,6 +101,7 @@
 			"AllowedPrefixes": [
 				"github.com/beorn7/perks/quantile",
 				"github.com/blang/semver",
+				"github.com/coredns/corefile-migration/migration",
 				"github.com/coreos/etcd/auth/authpb",
 				"github.com/coreos/etcd/clientv3",
 				"github.com/coreos/etcd/etcdserver/api/v3rpc/rpctypes",

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

@@ -120,7 +120,7 @@ func enforceRequirements(flags *applyPlanFlags, dryRun bool, newK8sVersion strin
 
 	// Ensure the user is root
 	klog.V(1).Info("running preflight checks")
-	if err := runPreflightChecks(ignorePreflightErrorsSet); err != nil {
+	if err := runPreflightChecks(client, ignorePreflightErrorsSet, &cfg.ClusterConfiguration); err != nil {
 		return nil, nil, nil, err
 	}
 
@@ -178,9 +178,17 @@ func printConfiguration(clustercfg *kubeadmapi.ClusterConfiguration, w io.Writer
 }
 
 // runPreflightChecks runs the root preflight check
-func runPreflightChecks(ignorePreflightErrors sets.String) error {
+func runPreflightChecks(client clientset.Interface, ignorePreflightErrors sets.String, cfg *kubeadmapi.ClusterConfiguration) error {
 	fmt.Println("[preflight] Running pre-flight checks.")
-	return preflight.RunRootCheckOnly(ignorePreflightErrors)
+	err := preflight.RunRootCheckOnly(ignorePreflightErrors)
+	if err != nil {
+		return err
+	}
+	err = upgrade.RunCoreDNSMigrationCheck(client, ignorePreflightErrors, cfg.DNS.Type)
+	if err != nil {
+		return err
+	}
+	return nil
 }
 
 // getClient gets a real or fake client depending on whether the user is dry-running or not

cmd/kubeadm/app/constants/constants.go

@@ -333,7 +333,7 @@ const (
 	KubeDNSVersion = "1.14.13"
 
 	// CoreDNSVersion is the version of CoreDNS to be deployed if it is used
-	CoreDNSVersion = "1.3.1"
+	CoreDNSVersion = "1.5.0"
 
 	// ClusterConfigurationKind is the string kind value for the ClusterConfiguration struct
 	ClusterConfigurationKind = "ClusterConfiguration"

cmd/kubeadm/app/phases/addons/dns/BUILD

@@ -44,9 +44,11 @@ go_library(
         "//staging/src/k8s.io/apimachinery/pkg/api/errors:go_default_library",
         "//staging/src/k8s.io/apimachinery/pkg/apis/meta/v1:go_default_library",
         "//staging/src/k8s.io/apimachinery/pkg/runtime:go_default_library",
+        "//staging/src/k8s.io/apimachinery/pkg/types:go_default_library",
         "//staging/src/k8s.io/client-go/kubernetes:go_default_library",
         "//staging/src/k8s.io/client-go/kubernetes/scheme:go_default_library",
         "//vendor/github.com/caddyserver/caddy/caddyfile:go_default_library",
+        "//vendor/github.com/coredns/corefile-migration/migration:go_default_library",
         "//vendor/github.com/pkg/errors:go_default_library",
         "//vendor/k8s.io/klog:go_default_library",
         "//vendor/k8s.io/utils/net:go_default_library",

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

@@ -23,6 +23,7 @@ import (
 	"strings"
 
 	"github.com/caddyserver/caddy/caddyfile"
+	"github.com/coredns/corefile-migration/migration"
 	"github.com/pkg/errors"
 
 	apps "k8s.io/api/apps/v1"
@@ -31,6 +32,7 @@ import (
 	apierrors "k8s.io/apimachinery/pkg/api/errors"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 	kuberuntime "k8s.io/apimachinery/pkg/runtime"
+	"k8s.io/apimachinery/pkg/types"
 	clientset "k8s.io/client-go/kubernetes"
 	clientsetscheme "k8s.io/client-go/kubernetes/scheme"
 	"k8s.io/klog"
@@ -228,9 +230,19 @@ func createCoreDNSAddon(deploymentBytes, serviceBytes, configBytes []byte, clien
 		return errors.Wrapf(err, "%s ConfigMap", unableToDecodeCoreDNS)
 	}
 
-	// Create the ConfigMap for CoreDNS or retain it in case it already exists
+	// Create the ConfigMap for CoreDNS or update/migrate it in case it already exists
-	if err := apiclient.CreateOrRetainConfigMap(client, coreDNSConfigMap, kubeadmconstants.CoreDNSConfigMap); err != nil {
+	_, corefile, currentInstalledCoreDNSVersion, err := GetCoreDNSInfo(client)
-		return err
+	if err != nil {
+		return errors.Wrap(err, "unable to fetch CoreDNS current installed version and ConfigMap.")
+	}
+	if IsCoreDNSConfigMapMigrationRequired(corefile) {
+		if err := migrateCoreDNSCorefile(client, coreDNSConfigMap, corefile, currentInstalledCoreDNSVersion); err != nil {
+			return err
+		}
+	} else {
+		if err := apiclient.CreateOrUpdateConfigMap(client, coreDNSConfigMap); err != nil {
+			return err
+		}
 	}
 
 	coreDNSClusterRoles := &rbac.ClusterRole{}
@@ -298,6 +310,102 @@ func createDNSService(dnsService *v1.Service, serviceBytes []byte, client client
 	return nil
 }
 
+// IsCoreDNSConfigMapMigrationRequired checks if a migration of the CoreDNS ConfigMap is required.
+func IsCoreDNSConfigMapMigrationRequired(corefile string) bool {
+	if corefile == "" || migration.Default("", corefile) {
+		return false
+	}
+	return true
+}
+
+func migrateCoreDNSCorefile(client clientset.Interface, cm *v1.ConfigMap, corefile, currentInstalledCoreDNSVersion string) error {
+	// Take a copy of the Corefile data as `Corefile-backup` and update the ConfigMap
+	// Also point the CoreDNS deployment to the `Corefile-backup` data.
+
+	if _, err := client.CoreV1().ConfigMaps(cm.ObjectMeta.Namespace).Update(&v1.ConfigMap{
+		ObjectMeta: metav1.ObjectMeta{
+			Name:      kubeadmconstants.CoreDNSConfigMap,
+			Namespace: metav1.NamespaceSystem,
+		},
+		Data: map[string]string{
+			"Corefile":        corefile,
+			"Corefile-backup": corefile,
+		},
+	}); err != nil {
+		return errors.Wrap(err, "unable to update the CoreDNS ConfigMap with backup Corefile")
+	}
+	if err := patchCoreDNSDeployment(client, "Corefile-backup"); err != nil {
+		return err
+	}
+
+	// Since the current configuration present is not the default version, try and migrate it.
+	updatedCorefile, err := migration.Migrate(currentInstalledCoreDNSVersion, kubeadmconstants.CoreDNSVersion, corefile, false)
+	if err != nil {
+		return errors.Wrap(err, "unable to migrate CoreDNS ConfigMap")
+	}
+
+	if _, err := client.CoreV1().ConfigMaps(cm.ObjectMeta.Namespace).Update(&v1.ConfigMap{
+		ObjectMeta: metav1.ObjectMeta{
+			Name:      kubeadmconstants.CoreDNSConfigMap,
+			Namespace: metav1.NamespaceSystem,
+		},
+		Data: map[string]string{
+			"Corefile":        updatedCorefile,
+			"Corefile-backup": corefile,
+		},
+	}); err != nil {
+		return errors.Wrap(err, "unable to update the CoreDNS ConfigMap")
+	}
+	fmt.Println("[addons]: Migrating CoreDNS Corefile")
+	changes, err := migration.Deprecated(currentInstalledCoreDNSVersion, kubeadmconstants.CoreDNSVersion, corefile)
+	if err != nil {
+		return errors.Wrap(err, "unable to get list of changes to the configuration.")
+	}
+	// show the migration changes
+	klog.V(2).Infof("the CoreDNS configuration has been migrated and applied: %v.", updatedCorefile)
+	klog.V(2).Infoln("the old migration has been saved in the CoreDNS ConfigMap under the name [Corefile-backup]")
+	klog.V(2).Infoln("The changes in the new CoreDNS Configuration are as follows:")
+	for _, change := range changes {
+		klog.V(2).Infof("%v", change.ToString())
+	}
+	return nil
+}
+
+// GetCoreDNSInfo gets the current CoreDNS installed and the current Corefile Configuration of CoreDNS.
+func GetCoreDNSInfo(client clientset.Interface) (*v1.ConfigMap, string, string, error) {
+	coreDNSConfigMap, err := client.CoreV1().ConfigMaps(metav1.NamespaceSystem).Get(kubeadmconstants.CoreDNSConfigMap, metav1.GetOptions{})
+	if err != nil && !apierrors.IsNotFound(err) {
+		return nil, "", "", err
+	}
+	if apierrors.IsNotFound(err) {
+		return nil, "", "", nil
+	}
+	corefile, ok := coreDNSConfigMap.Data["Corefile"]
+	if !ok {
+		return nil, "", "", errors.New("unable to find the CoreDNS Corefile data")
+	}
+
+	_, currentCoreDNSversion, err := DeployedDNSAddon(client)
+	if err != nil {
+		return nil, "", "", err
+	}
+
+	return coreDNSConfigMap, corefile, currentCoreDNSversion, nil
+}
+
+func patchCoreDNSDeployment(client clientset.Interface, coreDNSCorefileName string) error {
+	dnsDeployment, err := client.AppsV1().Deployments(metav1.NamespaceSystem).Get(kubeadmconstants.CoreDNSDeploymentName, metav1.GetOptions{})
+	if err != nil {
+		return err
+	}
+	patch := fmt.Sprintf(`{"spec":{"template":{"spec":{"volumes":[{"name": "config-volume", "configMap":{"name": "coredns", "items":[{"key": "%s", "path": "%s"}]}}]}}}}`, coreDNSCorefileName, coreDNSCorefileName)
+
+	if _, err := client.AppsV1().Deployments(dnsDeployment.ObjectMeta.Namespace).Patch(dnsDeployment.Name, types.StrategicMergePatchType, []byte(patch)); err != nil {
+		return errors.Wrap(err, "unable to patch the CoreDNS deployment")
+	}
+	return nil
+}
+
 // translateStubDomainOfKubeDNSToForwardCoreDNS translates StubDomain Data in kube-dns ConfigMap
 // in the form of Proxy for the CoreDNS Corefile.
 func translateStubDomainOfKubeDNSToForwardCoreDNS(dataField string, kubeDNSConfigMap *v1.ConfigMap) (string, error) {
@@ -351,7 +459,7 @@ func translateStubDomainOfKubeDNSToForwardCoreDNS(dataField string, kubeDNSConfi
 // in the form of Proxy for the CoreDNS Corefile.
 func translateUpstreamNameServerOfKubeDNSToUpstreamForwardCoreDNS(dataField string, kubeDNSConfigMap *v1.ConfigMap) (string, error) {
 	if kubeDNSConfigMap == nil {
-		return "", nil
+		return "/etc/resolv.conf", nil
 	}
 
 	if upstreamValues, ok := kubeDNSConfigMap.Data[dataField]; ok {

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

@@ -568,10 +568,11 @@ func TestDeploymentsHaveSystemClusterCriticalPriorityClassName(t *testing.T) {
 		{
 			name:     "CoreDNSDeployment",
 			manifest: CoreDNSDeployment,
-			data: struct{ DeploymentName, Image, ControlPlaneTaintKey string }{
+			data: struct{ DeploymentName, Image, ControlPlaneTaintKey, CoreDNSConfigMapName string }{
 				DeploymentName:       "foo",
 				Image:                "foo",
 				ControlPlaneTaintKey: "foo",
+				CoreDNSConfigMapName: "foo",
 			},
 		},
 	}
@@ -588,3 +589,150 @@ func TestDeploymentsHaveSystemClusterCriticalPriorityClassName(t *testing.T) {
 		})
 	}
 }
+
+func TestCreateCoreDNSConfigMap(t *testing.T) {
+	tests := []struct {
+		name                 string
+		initialCorefileData  string
+		expectedCorefileData string
+		coreDNSVersion       string
+	}{
+		{
+			name: "Remove Deprecated options",
+			initialCorefileData: `.:53 {
+        errors
+        health
+        kubernetes cluster.local in-addr.arpa ip6.arpa {
+           pods insecure
+           upstream
+           fallthrough in-addr.arpa ip6.arpa
+           ttl 30
+        }
+        prometheus :9153
+        forward . /etc/resolv.conf
+        cache 30
+        loop
+        reload
+        loadbalance
+    }`,
+			expectedCorefileData: `.:53 {
+    errors
+    health
+    kubernetes cluster.local in-addr.arpa ip6.arpa {
+        pods insecure
+        fallthrough in-addr.arpa ip6.arpa
+        ttl 30
+    }
+    prometheus :9153
+    forward . /etc/resolv.conf
+    cache 30
+    loop
+    reload
+    loadbalance
+    ready
+}
+`,
+			coreDNSVersion: "1.3.1",
+		},
+		{
+			name: "Update proxy plugin to forward plugin",
+			initialCorefileData: `.:53 {
+        errors
+        health
+        kubernetes cluster.local in-addr.arpa ip6.arpa {
+           pods insecure
+           upstream
+           fallthrough in-addr.arpa ip6.arpa
+        }
+        prometheus :9153
+        proxy . /etc/resolv.conf
+        k8s_external example.com
+        cache 30
+        loop
+        reload
+        loadbalance
+    }`,
+			expectedCorefileData: `.:53 {
+    errors
+    health
+    kubernetes cluster.local in-addr.arpa ip6.arpa {
+        pods insecure
+        fallthrough in-addr.arpa ip6.arpa
+    }
+    prometheus :9153
+    forward . /etc/resolv.conf
+    k8s_external example.com
+    cache 30
+    loop
+    reload
+    loadbalance
+    ready
+}
+`,
+			coreDNSVersion: "1.3.1",
+		},
+	}
+
+	for _, tc := range tests {
+		t.Run(tc.name, func(t *testing.T) {
+			client := createClientAndCoreDNSManifest(t, tc.initialCorefileData, tc.coreDNSVersion)
+			// Get the Corefile and installed CoreDNS version.
+			cm, corefile, currentInstalledCoreDNSVersion, err := GetCoreDNSInfo(client)
+			if err != nil {
+				t.Fatalf("unable to fetch CoreDNS current installed version and ConfigMap.")
+			}
+			err = migrateCoreDNSCorefile(client, cm, corefile, currentInstalledCoreDNSVersion)
+			if err != nil {
+				t.Fatalf("error creating the CoreDNS ConfigMap: %v", err)
+			}
+			migratedConfigMap, _ := client.CoreV1().ConfigMaps(metav1.NamespaceSystem).Get(kubeadmconstants.CoreDNSConfigMap, metav1.GetOptions{})
+			if !strings.EqualFold(migratedConfigMap.Data["Corefile"], tc.expectedCorefileData) {
+				t.Fatalf("expected to get %v, but got %v", tc.expectedCorefileData, migratedConfigMap.Data["Corefile"])
+			}
+		})
+	}
+}
+
+func createClientAndCoreDNSManifest(t *testing.T, corefile, coreDNSVersion string) *clientsetfake.Clientset {
+	client := clientsetfake.NewSimpleClientset()
+	_, err := client.CoreV1().ConfigMaps(metav1.NamespaceSystem).Create(&v1.ConfigMap{
+		ObjectMeta: metav1.ObjectMeta{
+			Name:      kubeadmconstants.CoreDNSConfigMap,
+			Namespace: metav1.NamespaceSystem,
+		},
+		Data: map[string]string{
+			"Corefile": corefile,
+		},
+	})
+	if err != nil {
+		t.Fatalf("error creating ConfigMap: %v", err)
+	}
+	_, err = client.AppsV1().Deployments(metav1.NamespaceSystem).Create(&apps.Deployment{
+		TypeMeta: metav1.TypeMeta{
+			Kind:       "Deployment",
+			APIVersion: "apps/v1",
+		},
+		ObjectMeta: metav1.ObjectMeta{
+			Name:      kubeadmconstants.CoreDNSConfigMap,
+			Namespace: metav1.NamespaceSystem,
+			Labels: map[string]string{
+				"k8s-app": "kube-dns",
+			},
+		},
+		Spec: apps.DeploymentSpec{
+			Template: v1.PodTemplateSpec{
+				Spec: v1.PodSpec{
+					Containers: []v1.Container{
+						{
+							Image: "test:" + coreDNSVersion,
+						},
+					},
+				},
+			},
+		},
+	})
+	if err != nil {
+		t.Fatalf("error creating deployment: %v", err)
+	}
+	return client
+}

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

@@ -281,8 +281,8 @@ spec:
           failureThreshold: 5
         readinessProbe:
           httpGet:
-            path: /health
+            path: /ready
-            port: 8080
+            port: 8181
             scheme: HTTP
         securityContext:
           allowPrivilegeEscalation: false
@@ -314,9 +314,9 @@ data:
     .:53 {
         errors
         health
+        ready
         kubernetes {{ .DNSDomain }} in-addr.arpa ip6.arpa {
            pods insecure
-           upstream
            fallthrough in-addr.arpa ip6.arpa
            ttl 30
         }{{ .Federation }}

cmd/kubeadm/app/phases/upgrade/BUILD

@@ -7,6 +7,7 @@ go_library(
         "health.go",
         "policy.go",
         "postupgrade.go",
+        "preflight.go",
         "prepull.go",
         "staticpods.go",
         "versiongetter.go",
@@ -44,7 +45,9 @@ go_library(
         "//staging/src/k8s.io/apimachinery/pkg/util/sets:go_default_library",
         "//staging/src/k8s.io/apimachinery/pkg/util/version:go_default_library",
         "//staging/src/k8s.io/client-go/kubernetes:go_default_library",
+        "//vendor/github.com/coredns/corefile-migration/migration:go_default_library",
         "//vendor/github.com/pkg/errors:go_default_library",
+        "//vendor/k8s.io/klog:go_default_library",
         "//vendor/k8s.io/utils/pointer:go_default_library",
     ],
 )

cmd/kubeadm/app/phases/upgrade/preflight.go

@@ -0,0 +1,114 @@
+/*
+Copyright 2019 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.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package upgrade
+
+import (
+	"os"
+
+	"github.com/coredns/corefile-migration/migration"
+	"github.com/pkg/errors"
+
+	"k8s.io/apimachinery/pkg/util/sets"
+	clientset "k8s.io/client-go/kubernetes"
+	"k8s.io/klog"
+	kubeadmapi "k8s.io/kubernetes/cmd/kubeadm/app/apis/kubeadm"
+	kubeadmconstants "k8s.io/kubernetes/cmd/kubeadm/app/constants"
+	"k8s.io/kubernetes/cmd/kubeadm/app/phases/addons/dns"
+	"k8s.io/kubernetes/cmd/kubeadm/app/preflight"
+)
+
+// CoreDNSCheck validates installed kubelet version
+type CoreDNSCheck struct {
+	name   string
+	client clientset.Interface
+	f      func(clientset.Interface) error
+}
+
+// Name is part of the preflight.Checker interface
+func (c CoreDNSCheck) Name() string {
+	return c.name
+}
+
+// Check is part of the preflight.Checker interface
+func (c CoreDNSCheck) Check() (warnings, errors []error) {
+	if err := c.f(c.client); err != nil {
+		return nil, []error{err}
+	}
+	return nil, nil
+}
+
+// RunCoreDNSMigrationCheck initializes checks related to CoreDNS migration.
+func RunCoreDNSMigrationCheck(client clientset.Interface, ignorePreflightErrors sets.String, dnsType kubeadmapi.DNSAddOnType) error {
+	if dnsType != kubeadmapi.CoreDNS {
+		return nil
+	}
+	migrationChecks := []preflight.Checker{
+		&CoreDNSCheck{
+			name:   "CoreDNSUnsupportedPlugins",
+			client: client,
+			f:      checkUnsupportedPlugins,
+		},
+		&CoreDNSCheck{
+			name:   "CoreDNSMigration",
+			client: client,
+			f:      checkMigration,
+		},
+	}
+
+	return preflight.RunChecks(migrationChecks, os.Stderr, ignorePreflightErrors)
+}
+
+// checkUnsupportedPlugins checks if there are any plugins included in the current configuration
+// that are unsupported for migration.
+func checkUnsupportedPlugins(client clientset.Interface) error {
+	klog.V(1).Infoln("validating if there are any unsupported CoreDNS plugins in the Corefile")
+	_, corefile, currentInstalledCoreDNSversion, err := dns.GetCoreDNSInfo(client)
+	if err != nil {
+		return err
+	}
+	unsupportedCoreDNS, err := migration.Unsupported(currentInstalledCoreDNSversion, kubeadmconstants.CoreDNSVersion, corefile)
+	if err != nil {
+		return err
+	}
+	if unsupportedCoreDNS != nil {
+		var UnsupportedPlugins, UnsupportedVersion string
+		for _, unsup := range unsupportedCoreDNS {
+			UnsupportedPlugins = unsup.Plugin
+			UnsupportedVersion = unsup.Version
+
+		}
+		if UnsupportedPlugins != "" || UnsupportedVersion != "" {
+			return errors.New("there are unsupported plugins in the CoreDNS Corefile")
+		}
+	}
+	return nil
+}
+
+// checkMigration validates if migration of the current CoreDNS ConfigMap is possible.
+func checkMigration(client clientset.Interface) error {
+	klog.V(1).Infoln("validating if migration can be done for the current CoreDNS release.")
+	_, corefile, currentInstalledCoreDNSversion, err := dns.GetCoreDNSInfo(client)
+	if err != nil {
+		return err
+	}
+
+	_, err = migration.Migrate(currentInstalledCoreDNSversion, kubeadmconstants.CoreDNSVersion, corefile, false)
+	if err != nil {
+		return err
+	}
+	return nil
+}

go.mod

@@ -25,7 +25,7 @@ require (
 	github.com/bazelbuild/buildtools v0.0.0-20180226164855-80c7f0d45d7e
 	github.com/blang/semver v3.5.0+incompatible
 	github.com/boltdb/bolt v1.3.1 // indirect
-	github.com/caddyserver/caddy v1.0.1
+	github.com/caddyserver/caddy v1.0.3
 	github.com/cespare/prettybench v0.0.0-20150116022406-03b8cfe5406c
 	github.com/checkpoint-restore/go-criu v0.0.0-20190109184317-bdb7599cd87b // indirect
 	github.com/client9/misspell v0.3.4
@@ -37,6 +37,7 @@ require (
 	github.com/containerd/containerd v1.0.2 // indirect
 	github.com/containerd/typeurl v0.0.0-20190228175220-2a93cfde8c20 // indirect
 	github.com/containernetworking/cni v0.7.1
+	github.com/coredns/corefile-migration v1.0.2
 	github.com/coreos/etcd v3.3.13+incompatible
 	github.com/coreos/go-systemd v0.0.0-20180511133405-39ca1b05acc7
 	github.com/coreos/pkg v0.0.0-20180108230652-97fdf19511ea
@@ -115,7 +116,7 @@ require (
 	github.com/seccomp/libseccomp-golang v0.9.1 // indirect
 	github.com/smartystreets/goconvey v0.0.0-20190330032615-68dc04aab96a // indirect
 	github.com/spf13/afero v1.2.2
-	github.com/spf13/cobra v0.0.4
+	github.com/spf13/cobra v0.0.5
 	github.com/spf13/jwalterweatherman v1.1.0 // indirect
 	github.com/spf13/pflag v1.0.3
 	github.com/spf13/viper v1.3.2
@@ -211,7 +212,7 @@ replace (
 	github.com/bifurcation/mint => github.com/bifurcation/mint v0.0.0-20180715133206-93c51c6ce115
 	github.com/blang/semver => github.com/blang/semver v3.5.0+incompatible
 	github.com/boltdb/bolt => github.com/boltdb/bolt v1.3.1
-	github.com/caddyserver/caddy => github.com/caddyserver/caddy v1.0.1
+	github.com/caddyserver/caddy => github.com/caddyserver/caddy v1.0.3
 	github.com/cenkalti/backoff => github.com/cenkalti/backoff v2.1.1+incompatible
 	github.com/cespare/prettybench => github.com/cespare/prettybench v0.0.0-20150116022406-03b8cfe5406c
 	github.com/chai2010/gettext-go => github.com/chai2010/gettext-go v0.0.0-20160711120539-c6fed771bfd5
@@ -226,6 +227,7 @@ replace (
 	github.com/containerd/containerd => github.com/containerd/containerd v1.0.2
 	github.com/containerd/typeurl => github.com/containerd/typeurl v0.0.0-20190228175220-2a93cfde8c20
 	github.com/containernetworking/cni => github.com/containernetworking/cni v0.7.1
+	github.com/coredns/corefile-migration => github.com/coredns/corefile-migration v1.0.2
 	github.com/coreos/bbolt => github.com/coreos/bbolt v1.3.1-coreos.6
 	github.com/coreos/etcd => github.com/coreos/etcd v3.3.13+incompatible
 	github.com/coreos/go-etcd => github.com/coreos/go-etcd v2.0.0+incompatible
@@ -387,7 +389,7 @@ replace (
 	github.com/soheilhy/cmux => github.com/soheilhy/cmux v0.1.3
 	github.com/spf13/afero => github.com/spf13/afero v1.2.2
 	github.com/spf13/cast => github.com/spf13/cast v1.3.0
-	github.com/spf13/cobra => github.com/spf13/cobra v0.0.4
+	github.com/spf13/cobra => github.com/spf13/cobra v0.0.5
 	github.com/spf13/jwalterweatherman => github.com/spf13/jwalterweatherman v1.1.0
 	github.com/spf13/pflag => github.com/spf13/pflag v1.0.3
 	github.com/spf13/viper => github.com/spf13/viper v1.3.2

go.sum

@@ -63,8 +63,8 @@ github.com/blang/semver v3.5.0+incompatible h1:CGxCgetQ64DKk7rdZ++Vfnb1+ogGNnB17
 github.com/blang/semver v3.5.0+incompatible/go.mod h1:kRBLl5iJ+tD4TcOOxsy/0fnwebNt5EWlYSAyrTnjyyk=
 github.com/boltdb/bolt v1.3.1 h1:JQmyP4ZBrce+ZQu0dY660FMfatumYDLun9hBCUVIkF4=
 github.com/boltdb/bolt v1.3.1/go.mod h1:clJnj/oiGkjum5o1McbSZDSLxVThjynRyGBgiAx27Ps=
-github.com/caddyserver/caddy v1.0.1 h1:oor6ep+8NoJOabpFXhvjqjfeldtw1XSzfISVrbfqTKo=
+github.com/caddyserver/caddy v1.0.3 h1:i9gRhBgvc5ifchwWtSe7pDpsdS9+Q0Rw9oYQmYUTw1w=
-github.com/caddyserver/caddy v1.0.1/go.mod h1:G+ouvOY32gENkJC+jhgl62TyhvqEsFaDiZ4uw0RzP1E=
+github.com/caddyserver/caddy v1.0.3/go.mod h1:G+ouvOY32gENkJC+jhgl62TyhvqEsFaDiZ4uw0RzP1E=
 github.com/cenkalti/backoff v2.1.1+incompatible/go.mod h1:90ReRw6GdpyfrHakVjL/QHaoyV4aDUVVkXQJJJ3NXXM=
 github.com/cespare/prettybench v0.0.0-20150116022406-03b8cfe5406c h1:p8i+qCbr/dNhS2FoQhRpSS7X5+IlxTa94nRNYXu4fyo=
 github.com/cespare/prettybench v0.0.0-20150116022406-03b8cfe5406c/go.mod h1:Xe6ZsFhtM8HrDku0pxJ3/Lr51rwykrzgFwpmTzleatY=
@@ -91,6 +91,8 @@ github.com/containerd/typeurl v0.0.0-20190228175220-2a93cfde8c20 h1:14r0i3IeJj6z
 github.com/containerd/typeurl v0.0.0-20190228175220-2a93cfde8c20/go.mod h1:Cm3kwCdlkCfMSHURc+r6fwoGH6/F1hH3S4sg0rLFWPc=
 github.com/containernetworking/cni v0.7.1 h1:fE3r16wpSEyaqY4Z4oFrLMmIGfBYIKpPrHK31EJ9FzE=
 github.com/containernetworking/cni v0.7.1/go.mod h1:LGwApLUm2FpoOfxTDEeq8T9ipbpZ61X79hmU3w8FmsY=
+github.com/coredns/corefile-migration v1.0.2 h1:kQga1ATFIZdkBtU6c/oJdtASLcCRkDh3fW8vVyVdvUc=
+github.com/coredns/corefile-migration v1.0.2/go.mod h1:OFwBp/Wc9dJt5cAZzHWMNhK1r5L0p0jDwIBc6j8NC8E=
 github.com/coreos/bbolt v1.3.1-coreos.6 h1:uTXKg9gY70s9jMAKdfljFQcuh4e/BXOM+V+d00KFj3A=
 github.com/coreos/bbolt v1.3.1-coreos.6/go.mod h1:iRUV2dpdMOn7Bo10OQBFzIJO9kkE559Wcmn+qkEiiKk=
 github.com/coreos/etcd v3.3.13+incompatible h1:8F3hqu9fGYLBifCmRCJsicFqDx/D68Rt3q1JMazcgBQ=
@@ -389,8 +391,8 @@ github.com/spf13/afero v1.2.2 h1:5jhuqJyZCZf2JRofRvN/nIFgIWNzPa3/Vz8mYylgbWc=
 github.com/spf13/afero v1.2.2/go.mod h1:9ZxEEn6pIJ8Rxe320qSDBk6AsU0r9pR7Q4OcevTdifk=
 github.com/spf13/cast v1.3.0 h1:oget//CVOEoFewqQxwr0Ej5yjygnqGkvggSE/gB35Q8=
 github.com/spf13/cast v1.3.0/go.mod h1:Qx5cxh0v+4UWYiBimWS+eyWzqEqokIECu5etghLkUJE=
-github.com/spf13/cobra v0.0.4 h1:S0tLZ3VOKl2Te0hpq8+ke0eSJPfCnNTPiDlsfwi1/NE=
+github.com/spf13/cobra v0.0.5 h1:f0B+LkLX6DtmRH1isoNA9VTtNUK9K8xYd28JNNfOv/s=
-github.com/spf13/cobra v0.0.4/go.mod h1:3K3wKZymM7VvHMDS9+Akkh4K60UwM26emMESw8tLCHU=
+github.com/spf13/cobra v0.0.5/go.mod h1:3K3wKZymM7VvHMDS9+Akkh4K60UwM26emMESw8tLCHU=
 github.com/spf13/jwalterweatherman v1.1.0 h1:ue6voC5bR5F8YxI5S67j9i582FU4Qvo2bmqnqMYADFk=
 github.com/spf13/jwalterweatherman v1.1.0/go.mod h1:aNWZUN0dPAAO/Ljvb5BEdw96iTZ0EXowPYD95IqWIGo=
 github.com/spf13/pflag v1.0.3 h1:zPAT6CGy6wXeQ7NtTnaTerfKOsV6V6F8agHXFiazDkg=

staging/src/k8s.io/apiextensions-apiserver/go.mod

@@ -17,7 +17,7 @@ require (
 	github.com/googleapis/gnostic v0.0.0-20170729233727-0c5108395e2d
 	github.com/pborman/uuid v1.2.0
 	github.com/prometheus/client_golang v0.9.2
-	github.com/spf13/cobra v0.0.4
+	github.com/spf13/cobra v0.0.5
 	github.com/spf13/pflag v1.0.3
 	github.com/stretchr/testify v1.3.0
 	gopkg.in/yaml.v2 v2.2.2

staging/src/k8s.io/apiextensions-apiserver/go.sum

@@ -230,8 +230,8 @@ github.com/spf13/afero v1.1.2/go.mod h1:j4pytiNVoe2o6bmDsKpLACNPDBIoEAkihy7loJ1B
 github.com/spf13/afero v1.2.2 h1:5jhuqJyZCZf2JRofRvN/nIFgIWNzPa3/Vz8mYylgbWc=
 github.com/spf13/afero v1.2.2/go.mod h1:9ZxEEn6pIJ8Rxe320qSDBk6AsU0r9pR7Q4OcevTdifk=
 github.com/spf13/cast v1.3.0/go.mod h1:Qx5cxh0v+4UWYiBimWS+eyWzqEqokIECu5etghLkUJE=
-github.com/spf13/cobra v0.0.4 h1:S0tLZ3VOKl2Te0hpq8+ke0eSJPfCnNTPiDlsfwi1/NE=
+github.com/spf13/cobra v0.0.5 h1:f0B+LkLX6DtmRH1isoNA9VTtNUK9K8xYd28JNNfOv/s=
-github.com/spf13/cobra v0.0.4/go.mod h1:3K3wKZymM7VvHMDS9+Akkh4K60UwM26emMESw8tLCHU=
+github.com/spf13/cobra v0.0.5/go.mod h1:3K3wKZymM7VvHMDS9+Akkh4K60UwM26emMESw8tLCHU=
 github.com/spf13/jwalterweatherman v1.0.0/go.mod h1:cQK4TGJAtQXfYWX+Ddv3mKDzgVb68N+wFjFa4jdeBTo=
 github.com/spf13/pflag v0.0.0-20170130214245-9ff6c6923cff/go.mod h1:DYY7MBk1bdzusC3SYhjObp+wFpr4gzcvqqNjLnInEg4=
 github.com/spf13/pflag v1.0.3 h1:zPAT6CGy6wXeQ7NtTnaTerfKOsV6V6F8agHXFiazDkg=

staging/src/k8s.io/cli-runtime/go.mod

@@ -11,7 +11,7 @@ require (
 	github.com/ghodss/yaml v0.0.0-20180820084758-c7ce16629ff4 // indirect
 	github.com/go-openapi/spec v0.19.2 // indirect
 	github.com/pkg/errors v0.8.0
-	github.com/spf13/cobra v0.0.4
+	github.com/spf13/cobra v0.0.5
 	github.com/spf13/pflag v1.0.3
 	github.com/stretchr/testify v1.3.0
 	golang.org/x/text v0.3.2

staging/src/k8s.io/cli-runtime/go.sum

@@ -123,8 +123,8 @@ github.com/russross/blackfriday v1.5.2/go.mod h1:JO/DiYxRf+HjHt06OyowR9PTA263kcR
 github.com/spf13/afero v1.1.2/go.mod h1:j4pytiNVoe2o6bmDsKpLACNPDBIoEAkihy7loJ1B0CQ=
 github.com/spf13/afero v1.2.2/go.mod h1:9ZxEEn6pIJ8Rxe320qSDBk6AsU0r9pR7Q4OcevTdifk=
 github.com/spf13/cast v1.3.0/go.mod h1:Qx5cxh0v+4UWYiBimWS+eyWzqEqokIECu5etghLkUJE=
-github.com/spf13/cobra v0.0.4 h1:S0tLZ3VOKl2Te0hpq8+ke0eSJPfCnNTPiDlsfwi1/NE=
+github.com/spf13/cobra v0.0.5 h1:f0B+LkLX6DtmRH1isoNA9VTtNUK9K8xYd28JNNfOv/s=
-github.com/spf13/cobra v0.0.4/go.mod h1:3K3wKZymM7VvHMDS9+Akkh4K60UwM26emMESw8tLCHU=
+github.com/spf13/cobra v0.0.5/go.mod h1:3K3wKZymM7VvHMDS9+Akkh4K60UwM26emMESw8tLCHU=
 github.com/spf13/jwalterweatherman v1.0.0/go.mod h1:cQK4TGJAtQXfYWX+Ddv3mKDzgVb68N+wFjFa4jdeBTo=
 github.com/spf13/pflag v0.0.0-20170130214245-9ff6c6923cff/go.mod h1:DYY7MBk1bdzusC3SYhjObp+wFpr4gzcvqqNjLnInEg4=
 github.com/spf13/pflag v1.0.3 h1:zPAT6CGy6wXeQ7NtTnaTerfKOsV6V6F8agHXFiazDkg=

staging/src/k8s.io/kube-aggregator/go.mod

@@ -10,7 +10,7 @@ require (
 	github.com/go-openapi/spec v0.19.2
 	github.com/gogo/protobuf v1.2.2-0.20190723190241-65acae22fc9d
 	github.com/prometheus/client_golang v0.9.2
-	github.com/spf13/cobra v0.0.4
+	github.com/spf13/cobra v0.0.5
 	github.com/spf13/pflag v1.0.3
 	github.com/stretchr/testify v1.3.0
 	golang.org/x/net v0.0.0-20190812203447-cdfb69ac37fc

staging/src/k8s.io/kube-aggregator/go.sum

@@ -186,8 +186,8 @@ github.com/spf13/afero v1.1.2/go.mod h1:j4pytiNVoe2o6bmDsKpLACNPDBIoEAkihy7loJ1B
 github.com/spf13/afero v1.2.2 h1:5jhuqJyZCZf2JRofRvN/nIFgIWNzPa3/Vz8mYylgbWc=
 github.com/spf13/afero v1.2.2/go.mod h1:9ZxEEn6pIJ8Rxe320qSDBk6AsU0r9pR7Q4OcevTdifk=
 github.com/spf13/cast v1.3.0/go.mod h1:Qx5cxh0v+4UWYiBimWS+eyWzqEqokIECu5etghLkUJE=
-github.com/spf13/cobra v0.0.4 h1:S0tLZ3VOKl2Te0hpq8+ke0eSJPfCnNTPiDlsfwi1/NE=
+github.com/spf13/cobra v0.0.5 h1:f0B+LkLX6DtmRH1isoNA9VTtNUK9K8xYd28JNNfOv/s=
-github.com/spf13/cobra v0.0.4/go.mod h1:3K3wKZymM7VvHMDS9+Akkh4K60UwM26emMESw8tLCHU=
+github.com/spf13/cobra v0.0.5/go.mod h1:3K3wKZymM7VvHMDS9+Akkh4K60UwM26emMESw8tLCHU=
 github.com/spf13/jwalterweatherman v1.0.0/go.mod h1:cQK4TGJAtQXfYWX+Ddv3mKDzgVb68N+wFjFa4jdeBTo=
 github.com/spf13/pflag v0.0.0-20170130214245-9ff6c6923cff/go.mod h1:DYY7MBk1bdzusC3SYhjObp+wFpr4gzcvqqNjLnInEg4=
 github.com/spf13/pflag v1.0.3 h1:zPAT6CGy6wXeQ7NtTnaTerfKOsV6V6F8agHXFiazDkg=

staging/src/k8s.io/kubectl/go.mod

@@ -29,7 +29,7 @@ require (
 	github.com/opencontainers/go-digest v1.0.0-rc1 // indirect
 	github.com/russross/blackfriday v1.5.2
 	github.com/sirupsen/logrus v1.4.2 // indirect
-	github.com/spf13/cobra v0.0.4
+	github.com/spf13/cobra v0.0.5
 	github.com/spf13/pflag v1.0.3
 	github.com/stretchr/testify v1.3.0
 	golang.org/x/sys v0.0.0-20190616124812-15dcb6c0061f

staging/src/k8s.io/kubectl/go.sum

@@ -173,8 +173,8 @@ github.com/sirupsen/logrus v1.4.2/go.mod h1:tLMulIdttU9McNUspp0xgXVQah82FyeX6Mwd
 github.com/spf13/afero v1.1.2/go.mod h1:j4pytiNVoe2o6bmDsKpLACNPDBIoEAkihy7loJ1B0CQ=
 github.com/spf13/afero v1.2.2/go.mod h1:9ZxEEn6pIJ8Rxe320qSDBk6AsU0r9pR7Q4OcevTdifk=
 github.com/spf13/cast v1.3.0/go.mod h1:Qx5cxh0v+4UWYiBimWS+eyWzqEqokIECu5etghLkUJE=
-github.com/spf13/cobra v0.0.4 h1:S0tLZ3VOKl2Te0hpq8+ke0eSJPfCnNTPiDlsfwi1/NE=
+github.com/spf13/cobra v0.0.5 h1:f0B+LkLX6DtmRH1isoNA9VTtNUK9K8xYd28JNNfOv/s=
-github.com/spf13/cobra v0.0.4/go.mod h1:3K3wKZymM7VvHMDS9+Akkh4K60UwM26emMESw8tLCHU=
+github.com/spf13/cobra v0.0.5/go.mod h1:3K3wKZymM7VvHMDS9+Akkh4K60UwM26emMESw8tLCHU=
 github.com/spf13/jwalterweatherman v1.0.0/go.mod h1:cQK4TGJAtQXfYWX+Ddv3mKDzgVb68N+wFjFa4jdeBTo=
 github.com/spf13/pflag v0.0.0-20170130214245-9ff6c6923cff/go.mod h1:DYY7MBk1bdzusC3SYhjObp+wFpr4gzcvqqNjLnInEg4=
 github.com/spf13/pflag v1.0.3 h1:zPAT6CGy6wXeQ7NtTnaTerfKOsV6V6F8agHXFiazDkg=

staging/src/k8s.io/sample-apiserver/go.mod

@@ -7,7 +7,7 @@ go 1.12
 require (
 	github.com/go-openapi/spec v0.19.2
 	github.com/google/gofuzz v1.0.0
-	github.com/spf13/cobra v0.0.4
+	github.com/spf13/cobra v0.0.5
 	k8s.io/apimachinery v0.0.0
 	k8s.io/apiserver v0.0.0
 	k8s.io/client-go v0.0.0

staging/src/k8s.io/sample-apiserver/go.sum

@@ -183,8 +183,8 @@ github.com/spf13/afero v1.1.2/go.mod h1:j4pytiNVoe2o6bmDsKpLACNPDBIoEAkihy7loJ1B
 github.com/spf13/afero v1.2.2 h1:5jhuqJyZCZf2JRofRvN/nIFgIWNzPa3/Vz8mYylgbWc=
 github.com/spf13/afero v1.2.2/go.mod h1:9ZxEEn6pIJ8Rxe320qSDBk6AsU0r9pR7Q4OcevTdifk=
 github.com/spf13/cast v1.3.0/go.mod h1:Qx5cxh0v+4UWYiBimWS+eyWzqEqokIECu5etghLkUJE=
-github.com/spf13/cobra v0.0.4 h1:S0tLZ3VOKl2Te0hpq8+ke0eSJPfCnNTPiDlsfwi1/NE=
+github.com/spf13/cobra v0.0.5 h1:f0B+LkLX6DtmRH1isoNA9VTtNUK9K8xYd28JNNfOv/s=
-github.com/spf13/cobra v0.0.4/go.mod h1:3K3wKZymM7VvHMDS9+Akkh4K60UwM26emMESw8tLCHU=
+github.com/spf13/cobra v0.0.5/go.mod h1:3K3wKZymM7VvHMDS9+Akkh4K60UwM26emMESw8tLCHU=
 github.com/spf13/jwalterweatherman v1.0.0/go.mod h1:cQK4TGJAtQXfYWX+Ddv3mKDzgVb68N+wFjFa4jdeBTo=
 github.com/spf13/pflag v0.0.0-20170130214245-9ff6c6923cff/go.mod h1:DYY7MBk1bdzusC3SYhjObp+wFpr4gzcvqqNjLnInEg4=
 github.com/spf13/pflag v1.0.3 h1:zPAT6CGy6wXeQ7NtTnaTerfKOsV6V6F8agHXFiazDkg=

staging/src/k8s.io/sample-cli-plugin/go.mod

@@ -5,7 +5,7 @@ module k8s.io/sample-cli-plugin
 go 1.12
 
 require (
-	github.com/spf13/cobra v0.0.4
+	github.com/spf13/cobra v0.0.5
 	github.com/spf13/pflag v1.0.3
 	k8s.io/cli-runtime v0.0.0
 	k8s.io/client-go v0.0.0

staging/src/k8s.io/sample-cli-plugin/go.sum

@@ -123,8 +123,8 @@ github.com/russross/blackfriday v1.5.2/go.mod h1:JO/DiYxRf+HjHt06OyowR9PTA263kcR
 github.com/spf13/afero v1.1.2/go.mod h1:j4pytiNVoe2o6bmDsKpLACNPDBIoEAkihy7loJ1B0CQ=
 github.com/spf13/afero v1.2.2/go.mod h1:9ZxEEn6pIJ8Rxe320qSDBk6AsU0r9pR7Q4OcevTdifk=
 github.com/spf13/cast v1.3.0/go.mod h1:Qx5cxh0v+4UWYiBimWS+eyWzqEqokIECu5etghLkUJE=
-github.com/spf13/cobra v0.0.4 h1:S0tLZ3VOKl2Te0hpq8+ke0eSJPfCnNTPiDlsfwi1/NE=
+github.com/spf13/cobra v0.0.5 h1:f0B+LkLX6DtmRH1isoNA9VTtNUK9K8xYd28JNNfOv/s=
-github.com/spf13/cobra v0.0.4/go.mod h1:3K3wKZymM7VvHMDS9+Akkh4K60UwM26emMESw8tLCHU=
+github.com/spf13/cobra v0.0.5/go.mod h1:3K3wKZymM7VvHMDS9+Akkh4K60UwM26emMESw8tLCHU=
 github.com/spf13/jwalterweatherman v1.0.0/go.mod h1:cQK4TGJAtQXfYWX+Ddv3mKDzgVb68N+wFjFa4jdeBTo=
 github.com/spf13/pflag v0.0.0-20170130214245-9ff6c6923cff/go.mod h1:DYY7MBk1bdzusC3SYhjObp+wFpr4gzcvqqNjLnInEg4=
 github.com/spf13/pflag v1.0.3 h1:zPAT6CGy6wXeQ7NtTnaTerfKOsV6V6F8agHXFiazDkg=

vendor/BUILD

@@ -101,6 +101,7 @@ filegroup(
         "//vendor/github.com/containernetworking/cni/pkg/invoke:all-srcs",
         "//vendor/github.com/containernetworking/cni/pkg/types:all-srcs",
         "//vendor/github.com/containernetworking/cni/pkg/version:all-srcs",
+        "//vendor/github.com/coredns/corefile-migration/migration:all-srcs",
         "//vendor/github.com/coreos/bbolt:all-srcs",
         "//vendor/github.com/coreos/etcd/alarm:all-srcs",
         "//vendor/github.com/coreos/etcd/auth:all-srcs",

vendor/github.com/coredns/corefile-migration/LICENSE

@@ -0,0 +1,201 @@
+                                 Apache License
+                           Version 2.0, January 2004
+                        http://www.apache.org/licenses/
+
+   TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION
+
+   1. Definitions.
+
+      "License" shall mean the terms and conditions for use, reproduction,
+      and distribution as defined by Sections 1 through 9 of this document.
+
+      "Licensor" shall mean the copyright owner or entity authorized by
+      the copyright owner that is granting the License.
+
+      "Legal Entity" shall mean the union of the acting entity and all
+      other entities that control, are controlled by, or are under common
+      control with that entity. For the purposes of this definition,
+      "control" means (i) the power, direct or indirect, to cause the
+      direction or management of such entity, whether by contract or
+      otherwise, or (ii) ownership of fifty percent (50%) or more of the
+      outstanding shares, or (iii) beneficial ownership of such entity.
+
+      "You" (or "Your") shall mean an individual or Legal Entity
+      exercising permissions granted by this License.
+
+      "Source" form shall mean the preferred form for making modifications,
+      including but not limited to software source code, documentation
+      source, and configuration files.
+
+      "Object" form shall mean any form resulting from mechanical
+      transformation or translation of a Source form, including but
+      not limited to compiled object code, generated documentation,
+      and conversions to other media types.
+
+      "Work" shall mean the work of authorship, whether in Source or
+      Object form, made available under the License, as indicated by a
+      copyright notice that is included in or attached to the work
+      (an example is provided in the Appendix below).
+
+      "Derivative Works" shall mean any work, whether in Source or Object
+      form, that is based on (or derived from) the Work and for which the
+      editorial revisions, annotations, elaborations, or other modifications
+      represent, as a whole, an original work of authorship. For the purposes
+      of this License, Derivative Works shall not include works that remain
+      separable from, or merely link (or bind by name) to the interfaces of,
+      the Work and Derivative Works thereof.
+
+      "Contribution" shall mean any work of authorship, including
+      the original version of the Work and any modifications or additions
+      to that Work or Derivative Works thereof, that is intentionally
+      submitted to Licensor for inclusion in the Work by the copyright owner
+      or by an individual or Legal Entity authorized to submit on behalf of
+      the copyright owner. For the purposes of this definition, "submitted"
+      means any form of electronic, verbal, or written communication sent
+      to the Licensor or its representatives, including but not limited to
+      communication on electronic mailing lists, source code control systems,
+      and issue tracking systems that are managed by, or on behalf of, the
+      Licensor for the purpose of discussing and improving the Work, but
+      excluding communication that is conspicuously marked or otherwise
+      designated in writing by the copyright owner as "Not a Contribution."
+
+      "Contributor" shall mean Licensor and any individual or Legal Entity
+      on behalf of whom a Contribution has been received by Licensor and
+      subsequently incorporated within the Work.
+
+   2. Grant of Copyright License. Subject to the terms and conditions of
+      this License, each Contributor hereby grants to You a perpetual,
+      worldwide, non-exclusive, no-charge, royalty-free, irrevocable
+      copyright license to reproduce, prepare Derivative Works of,
+      publicly display, publicly perform, sublicense, and distribute the
+      Work and such Derivative Works in Source or Object form.
+
+   3. Grant of Patent License. Subject to the terms and conditions of
+      this License, each Contributor hereby grants to You a perpetual,
+      worldwide, non-exclusive, no-charge, royalty-free, irrevocable
+      (except as stated in this section) patent license to make, have made,
+      use, offer to sell, sell, import, and otherwise transfer the Work,
+      where such license applies only to those patent claims licensable
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+      Contribution(s) alone or by combination of their Contribution(s)
+      with the Work to which such Contribution(s) was submitted. If You
+      institute patent litigation against any entity (including a
+      cross-claim or counterclaim in a lawsuit) alleging that the Work
+      or a Contribution incorporated within the Work constitutes direct
+      or contributory patent infringement, then any patent licenses
+      granted to You under this License for that Work shall terminate
+      as of the date such litigation is filed.
+
+   4. Redistribution. You may reproduce and distribute copies of the
+      Work or Derivative Works thereof in any medium, with or without
+      modifications, and in Source or Object form, provided that You
+      meet the following conditions:
+
+      (a) You must give any other recipients of the Work or
+          Derivative Works a copy of this License; and
+
+      (b) You must cause any modified files to carry prominent notices
+          stating that You changed the files; and
+
+      (c) You must retain, in the Source form of any Derivative Works
+          that You distribute, all copyright, patent, trademark, and
+          attribution notices from the Source form of the Work,
+          excluding those notices that do not pertain to any part of
+          the Derivative Works; and
+
+      (d) If the Work includes a "NOTICE" text file as part of its
+          distribution, then any Derivative Works that You distribute must
+          include a readable copy of the attribution notices contained
+          within such NOTICE file, excluding those notices that do not
+          pertain to any part of the Derivative Works, in at least one
+          of the following places: within a NOTICE text file distributed
+          as part of the Derivative Works; within the Source form or
+          documentation, if provided along with the Derivative Works; or,
+          within a display generated by the Derivative Works, if and
+          wherever such third-party notices normally appear. The contents
+          of the NOTICE file are for informational purposes only and
+          do not modify the License. You may add Your own attribution
+          notices within Derivative Works that You distribute, alongside
+          or as an addendum to the NOTICE text from the Work, provided
+          that such additional attribution notices cannot be construed
+          as modifying the License.
+
+      You may add Your own copyright statement to Your modifications and
+      may provide additional or different license terms and conditions
+      for use, reproduction, or distribution of Your modifications, or
+      for any such Derivative Works as a whole, provided Your use,
+      reproduction, and distribution of the Work otherwise complies with
+      the conditions stated in this License.
+
+   5. Submission of Contributions. Unless You explicitly state otherwise,
+      any Contribution intentionally submitted for inclusion in the Work
+      by You to the Licensor shall be under the terms and conditions of
+      this License, without any additional terms or conditions.
+      Notwithstanding the above, nothing herein shall supersede or modify
+      the terms of any separate license agreement you may have executed
+      with Licensor regarding such Contributions.
+
+   6. Trademarks. This License does not grant permission to use the trade
+      names, trademarks, service marks, or product names of the Licensor,
+      except as required for reasonable and customary use in describing the
+      origin of the Work and reproducing the content of the NOTICE file.
+
+   7. Disclaimer of Warranty. Unless required by applicable law or
+      agreed to in writing, Licensor provides the Work (and each
+      Contributor provides its Contributions) on an "AS IS" BASIS,
+      WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
+      implied, including, without limitation, any warranties or conditions
+      of TITLE, NON-INFRINGEMENT, MERCHANTABILITY, or FITNESS FOR A
+      PARTICULAR PURPOSE. You are solely responsible for determining the
+      appropriateness of using or redistributing the Work and assume any
+      risks associated with Your exercise of permissions under this License.
+
+   8. Limitation of Liability. In no event and under no legal theory,
+      whether in tort (including negligence), contract, or otherwise,
+      unless required by applicable law (such as deliberate and grossly
+      negligent acts) or agreed to in writing, shall any Contributor be
+      liable to You for damages, including any direct, indirect, special,
+      incidental, or consequential damages of any character arising as a
+      result of this License or out of the use or inability to use the
+      Work (including but not limited to damages for loss of goodwill,
+      work stoppage, computer failure or malfunction, or any and all
+      other commercial damages or losses), even if such Contributor
+      has been advised of the possibility of such damages.
+
+   9. Accepting Warranty or Additional Liability. While redistributing
+      the Work or Derivative Works thereof, You may choose to offer,
+      and charge a fee for, acceptance of support, warranty, indemnity,
+      or other liability obligations and/or rights consistent with this
+      License. However, in accepting such obligations, You may act only
+      on Your own behalf and on Your sole responsibility, not on behalf
+      of any other Contributor, and only if You agree to indemnify,
+      defend, and hold each Contributor harmless for any liability
+      incurred by, or claims asserted against, such Contributor by reason
+      of your accepting any such warranty or additional liability.
+
+   END OF TERMS AND CONDITIONS
+
+   APPENDIX: How to apply the Apache License to your work.
+
+      To apply the Apache License to your work, attach the following
+      boilerplate notice, with the fields enclosed by brackets "[]"
+      replaced with your own identifying information. (Don't include
+      the brackets!)  The text should be enclosed in the appropriate
+      comment syntax for the file format. We also recommend that a
+      file or class name and description of purpose be included on the
+      same "printed page" as the copyright notice for easier
+      identification within third-party archives.
+
+   Copyright [yyyy] [name of copyright owner]
+
+   Licensed under the Apache License, Version 2.0 (the "License");
+   you may not use this file except in compliance with the License.
+   You may obtain a copy of the License at
+
+       http://www.apache.org/licenses/LICENSE-2.0
+
+   Unless required by applicable law or agreed to in writing, software
+   distributed under the License is distributed on an "AS IS" BASIS,
+   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+   See the License for the specific language governing permissions and
+   limitations under the License.

vendor/github.com/coredns/corefile-migration/migration/BUILD

@@ -0,0 +1,31 @@
+load("@io_bazel_rules_go//go:def.bzl", "go_library")
+
+go_library(
+    name = "go_default_library",
+    srcs = [
+        "migrate.go",
+        "notice.go",
+        "versions.go",
+    ],
+    importmap = "k8s.io/kubernetes/vendor/github.com/coredns/corefile-migration/migration",
+    importpath = "github.com/coredns/corefile-migration/migration",
+    visibility = ["//visibility:public"],
+    deps = ["//vendor/github.com/coredns/corefile-migration/migration/corefile:go_default_library"],
+)
+
+filegroup(
+    name = "package-srcs",
+    srcs = glob(["**"]),
+    tags = ["automanaged"],
+    visibility = ["//visibility:private"],
+)
+
+filegroup(
+    name = "all-srcs",
+    srcs = [
+        ":package-srcs",
+        "//vendor/github.com/coredns/corefile-migration/migration/corefile:all-srcs",
+    ],
+    tags = ["automanaged"],
+    visibility = ["//visibility:public"],
+)

vendor/github.com/coredns/corefile-migration/migration/corefile/BUILD

@@ -0,0 +1,24 @@
+load("@io_bazel_rules_go//go:def.bzl", "go_library")
+
+go_library(
+    name = "go_default_library",
+    srcs = ["corefile.go"],
+    importmap = "k8s.io/kubernetes/vendor/github.com/coredns/corefile-migration/migration/corefile",
+    importpath = "github.com/coredns/corefile-migration/migration/corefile",
+    visibility = ["//visibility:public"],
+    deps = ["//vendor/github.com/caddyserver/caddy/caddyfile:go_default_library"],
+)
+
+filegroup(
+    name = "package-srcs",
+    srcs = glob(["**"]),
+    tags = ["automanaged"],
+    visibility = ["//visibility:private"],
+)
+
+filegroup(
+    name = "all-srcs",
+    srcs = [":package-srcs"],
+    tags = ["automanaged"],
+    visibility = ["//visibility:public"],
+)

vendor/github.com/coredns/corefile-migration/migration/corefile/corefile.go

@@ -0,0 +1,179 @@
+package corefile
+
+import (
+	"strings"
+
+	"github.com/caddyserver/caddy/caddyfile"
+)
+
+type Corefile struct {
+	Servers []*Server
+}
+
+type Server struct {
+	DomPorts []string
+	Plugins  []*Plugin
+}
+
+type Plugin struct {
+	Name    string
+	Args    []string
+	Options []*Option
+}
+
+type Option struct {
+	Name string
+	Args []string
+}
+
+func New(s string) (*Corefile, error) {
+	c := Corefile{}
+	cc := caddyfile.NewDispenser("migration", strings.NewReader(s))
+	depth := 0
+	var cSvr *Server
+	var cPlg *Plugin
+	for cc.Next() {
+		if cc.Val() == "{" {
+			depth += 1
+			continue
+		} else if cc.Val() == "}" {
+			depth -= 1
+			continue
+		}
+		val := cc.Val()
+		args := cc.RemainingArgs()
+		switch depth {
+		case 0:
+			c.Servers = append(c.Servers,
+				&Server{
+					DomPorts: append([]string{val}, args...),
+				})
+			cSvr = c.Servers[len(c.Servers)-1]
+		case 1:
+			cSvr.Plugins = append(cSvr.Plugins,
+				&Plugin{
+					Name: val,
+					Args: args,
+				})
+			cPlg = cSvr.Plugins[len(cSvr.Plugins)-1]
+		case 2:
+			cPlg.Options = append(cPlg.Options,
+				&Option{
+					Name: val,
+					Args: args,
+				})
+		}
+	}
+	return &c, nil
+}
+
+func (c *Corefile) ToString() (out string) {
+	strs := []string{}
+	for _, s := range c.Servers {
+		strs = append(strs, s.ToString())
+	}
+	return strings.Join(strs, "\n")
+}
+
+func (s *Server) ToString() (out string) {
+	str := strings.Join(s.DomPorts, " ")
+	strs := []string{}
+	for _, p := range s.Plugins {
+		strs = append(strs, strings.Repeat(" ", indent)+p.ToString())
+	}
+	if len(strs) > 0 {
+		str += " {\n" + strings.Join(strs, "\n") + "\n}\n"
+	}
+	return str
+}
+
+func (p *Plugin) ToString() (out string) {
+	str := strings.Join(append([]string{p.Name}, p.Args...), " ")
+	strs := []string{}
+	for _, o := range p.Options {
+		strs = append(strs, strings.Repeat(" ", indent*2)+o.ToString())
+	}
+	if len(strs) > 0 {
+		str += " {\n" + strings.Join(strs, "\n") + "\n" + strings.Repeat(" ", indent*1) + "}"
+	}
+	return str
+}
+
+func (o *Option) ToString() (out string) {
+	str := strings.Join(append([]string{o.Name}, o.Args...), " ")
+	return str
+}
+
+func (s *Server) FindMatch(def []*Server) (*Server, bool) {
+NextServer:
+	for _, sDef := range def {
+		for i, dp := range sDef.DomPorts {
+			if dp == "*" {
+				continue
+			}
+			if dp == "***" {
+				return sDef, true
+			}
+			if i >= len(s.DomPorts) || dp != s.DomPorts[i] {
+				continue NextServer
+			}
+		}
+		if len(sDef.DomPorts) != len(s.DomPorts) {
+			continue
+		}
+		return sDef, true
+	}
+	return nil, false
+}
+
+func (p *Plugin) FindMatch(def []*Plugin) (*Plugin, bool) {
+NextPlugin:
+	for _, pDef := range def {
+		if pDef.Name != p.Name {
+			continue
+		}
+		for i, arg := range pDef.Args {
+			if arg == "*" {
+				continue
+			}
+			if arg == "***" {
+				return pDef, true
+			}
+			if i >= len(p.Args) || arg != p.Args[i] {
+				continue NextPlugin
+			}
+		}
+		if len(pDef.Args) != len(p.Args) {
+			continue
+		}
+		return pDef, true
+	}
+	return nil, false
+}
+
+func (o *Option) FindMatch(def []*Option) (*Option, bool) {
+NextPlugin:
+	for _, oDef := range def {
+		if oDef.Name != o.Name {
+			continue
+		}
+		for i, arg := range oDef.Args {
+			if arg == "*" {
+				continue
+			}
+			if arg == "***" {
+				return oDef, true
+			}
+			if i >= len(o.Args) || arg != o.Args[i] {
+				continue NextPlugin
+			}
+		}
+		if len(oDef.Args) != len(o.Args) {
+			continue
+		}
+		return oDef, true
+	}
+	return nil, false
+}
+
+const indent = 4

vendor/github.com/coredns/corefile-migration/migration/migrate.go

@@ -0,0 +1,445 @@
+package migration
+
+// This package provides a set of functions to help handle migrations of CoreDNS Corefiles to be compatible with new
+// versions of CoreDNS. The task of upgrading CoreDNS is the responsibility of a variety of Kubernetes management tools
+// (e.g. kubeadm and others), and the precise behavior may be different for each one. This library abstracts some basic
+// helper functions that make this easier to implement.
+
+import (
+	"fmt"
+	"sort"
+
+	"github.com/coredns/corefile-migration/migration/corefile"
+)
+
+// Deprecated returns a list of deprecation notifications affecting the guven Corefile.  Notifications are returned for
+// any deprecated, removed, or ignored plugins/directives present in the Corefile.  Notifications are also returned for
+// any new default plugins that would be added in a migration.
+func Deprecated(fromCoreDNSVersion, toCoreDNSVersion, corefileStr string) ([]Notice, error) {
+	return getStatus(fromCoreDNSVersion, toCoreDNSVersion, corefileStr, all)
+}
+
+// Unsupported returns a list notifications of plugins/options that are not handled supported by this migration tool,
+// but may still be valid in CoreDNS.
+func Unsupported(fromCoreDNSVersion, toCoreDNSVersion, corefileStr string) ([]Notice, error) {
+	return getStatus(fromCoreDNSVersion, toCoreDNSVersion, corefileStr, unsupported)
+}
+
+func getStatus(fromCoreDNSVersion, toCoreDNSVersion, corefileStr, status string) ([]Notice, error) {
+	if fromCoreDNSVersion == toCoreDNSVersion {
+		return nil, nil
+	}
+	err := validUpMigration(fromCoreDNSVersion, toCoreDNSVersion)
+	if err != nil {
+		return nil, err
+	}
+	cf, err := corefile.New(corefileStr)
+	if err != nil {
+		return nil, err
+	}
+	notices := []Notice{}
+	v := fromCoreDNSVersion
+	for {
+		v = Versions[v].nextVersion
+		for _, s := range cf.Servers {
+			for _, p := range s.Plugins {
+				vp, present := Versions[v].plugins[p.Name]
+				if status == unsupported {
+					if present {
+						continue
+					}
+					notices = append(notices, Notice{Plugin: p.Name, Severity: status, Version: v})
+					continue
+				}
+				if !present {
+					continue
+				}
+				if vp.status != "" && vp.status != newdefault {
+					notices = append(notices, Notice{
+						Plugin:     p.Name,
+						Severity:   vp.status,
+						Version:    v,
+						ReplacedBy: vp.replacedBy,
+						Additional: vp.additional,
+					})
+					continue
+				}
+				for _, o := range p.Options {
+					vo, present := Versions[v].plugins[p.Name].options[o.Name]
+					if status == unsupported {
+						if present {
+							continue
+						}
+						notices = append(notices, Notice{
+							Plugin:     p.Name,
+							Option:     o.Name,
+							Severity:   status,
+							Version:    v,
+							ReplacedBy: vo.replacedBy,
+							Additional: vo.additional,
+						})
+						continue
+					}
+					if !present {
+						continue
+					}
+					if vo.status != "" && vo.status != newdefault {
+						notices = append(notices, Notice{Plugin: p.Name, Option: o.Name, Severity: vo.status, Version: v})
+						continue
+					}
+				}
+				if status != unsupported {
+				CheckForNewOptions:
+					for name, vo := range Versions[v].plugins[p.Name].options {
+						if vo.status != newdefault {
+							continue
+						}
+						for _, o := range p.Options {
+							if name == o.Name {
+								continue CheckForNewOptions
+							}
+						}
+						notices = append(notices, Notice{Plugin: p.Name, Option: name, Severity: newdefault, Version: v})
+					}
+				}
+			}
+			if status != unsupported {
+			CheckForNewPlugins:
+				for name, vp := range Versions[v].plugins {
+					if vp.status != newdefault {
+						continue
+					}
+					for _, p := range s.Plugins {
+						if name == p.Name {
+							continue CheckForNewPlugins
+						}
+					}
+					notices = append(notices, Notice{Plugin: name, Option: "", Severity: newdefault, Version: v})
+				}
+			}
+		}
+		if v == toCoreDNSVersion {
+			break
+		}
+	}
+	return notices, nil
+}
+
+// Migrate returns the Corefile converted to toCoreDNSVersion, or an error if it cannot.  This function only accepts
+// a forward migration, where the destination version is => the start version.
+// If deprecations is true, deprecated plugins/options will be migrated as soon as they are deprecated.
+// If deprecations is false, deprecated plugins/options will be migrated only once they become removed or ignored.
+func Migrate(fromCoreDNSVersion, toCoreDNSVersion, corefileStr string, deprecations bool) (string, error) {
+	if fromCoreDNSVersion == toCoreDNSVersion {
+		return corefileStr, nil
+	}
+	err := validUpMigration(fromCoreDNSVersion, toCoreDNSVersion)
+	if err != nil {
+		return "", err
+	}
+	cf, err := corefile.New(corefileStr)
+	if err != nil {
+		return "", err
+	}
+	v := fromCoreDNSVersion
+	for {
+		v = Versions[v].nextVersion
+		newSrvs := []*corefile.Server{}
+		for _, s := range cf.Servers {
+			newPlugs := []*corefile.Plugin{}
+			for _, p := range s.Plugins {
+				vp, present := Versions[v].plugins[p.Name]
+				if !present {
+					newPlugs = append(newPlugs, p)
+					continue
+				}
+				if !deprecations && vp.status == deprecated {
+					newPlugs = append(newPlugs, p)
+					continue
+				}
+				if vp.action != nil {
+					p, err := vp.action(p)
+					if err != nil {
+						return "", err
+					}
+					if p == nil {
+						// remove plugin, skip options processing
+						continue
+					}
+				}
+				newOpts := []*corefile.Option{}
+				for _, o := range p.Options {
+					vo, present := Versions[v].plugins[p.Name].options[o.Name]
+					if !present {
+						newOpts = append(newOpts, o)
+						continue
+					}
+					if !deprecations && vo.status == deprecated {
+						newOpts = append(newOpts, o)
+						continue
+					}
+					if vo.action == nil {
+						newOpts = append(newOpts, o)
+						continue
+					}
+					o, err := vo.action(o)
+					if err != nil {
+						return "", err
+					}
+					if o == nil {
+						// remove option
+						continue
+					}
+					newOpts = append(newOpts, o)
+				}
+				newPlug := &corefile.Plugin{
+					Name:    p.Name,
+					Args:    p.Args,
+					Options: newOpts,
+				}
+			CheckForNewOptions:
+				for name, vo := range Versions[v].plugins[p.Name].options {
+					if vo.status != newdefault {
+						continue
+					}
+					for _, o := range p.Options {
+						if name == o.Name {
+							continue CheckForNewOptions
+						}
+					}
+					newPlug, err = vo.add(newPlug)
+					if err != nil {
+						return "", err
+					}
+				}
+
+				newPlugs = append(newPlugs, newPlug)
+			}
+			newSrv := &corefile.Server{
+				DomPorts: s.DomPorts,
+				Plugins:  newPlugs,
+			}
+		CheckForNewPlugins:
+			for name, vp := range Versions[v].plugins {
+				if vp.status != newdefault {
+					continue
+				}
+				for _, p := range s.Plugins {
+					if name == p.Name {
+						continue CheckForNewPlugins
+					}
+				}
+				newSrv, err = vp.add(newSrv)
+				if err != nil {
+					return "", err
+				}
+			}
+
+			newSrvs = append(newSrvs, newSrv)
+		}
+
+		cf = &corefile.Corefile{Servers: newSrvs}
+
+		// apply any global corefile level post processing
+		if Versions[v].postProcess != nil {
+			cf, err = Versions[v].postProcess(cf)
+			if err != nil {
+				return "", err
+			}
+		}
+
+		if v == toCoreDNSVersion {
+			break
+		}
+	}
+	return cf.ToString(), nil
+}
+
+// MigrateDown returns the Corefile converted to toCoreDNSVersion, or an error if it cannot. This function only accepts
+// a downward migration, where the destination version is <= the start version.
+func MigrateDown(fromCoreDNSVersion, toCoreDNSVersion, corefileStr string) (string, error) {
+	if fromCoreDNSVersion == toCoreDNSVersion {
+		return corefileStr, nil
+	}
+	err := validDownMigration(fromCoreDNSVersion, toCoreDNSVersion)
+	if err != nil {
+		return "", err
+	}
+	cf, err := corefile.New(corefileStr)
+	if err != nil {
+		return "", err
+	}
+	v := fromCoreDNSVersion
+	for {
+		newSrvs := []*corefile.Server{}
+		for _, s := range cf.Servers {
+			newPlugs := []*corefile.Plugin{}
+			for _, p := range s.Plugins {
+				vp, present := Versions[v].plugins[p.Name]
+				if !present {
+					newPlugs = append(newPlugs, p)
+					continue
+				}
+				if vp.downAction == nil {
+					newPlugs = append(newPlugs, p)
+					continue
+				}
+				p, err := vp.downAction(p)
+				if err != nil {
+					return "", err
+				}
+				if p == nil {
+					// remove plugin, skip options processing
+					continue
+				}
+
+				newOpts := []*corefile.Option{}
+				for _, o := range p.Options {
+					vo, present := Versions[v].plugins[p.Name].options[o.Name]
+					if !present {
+						newOpts = append(newOpts, o)
+						continue
+					}
+					if vo.downAction == nil {
+						newOpts = append(newOpts, o)
+						continue
+					}
+					o, err := vo.downAction(o)
+					if err != nil {
+						return "", err
+					}
+					if o == nil {
+						// remove option
+						continue
+					}
+					newOpts = append(newOpts, o)
+				}
+				newPlug := &corefile.Plugin{
+					Name:    p.Name,
+					Args:    p.Args,
+					Options: newOpts,
+				}
+				newPlugs = append(newPlugs, newPlug)
+			}
+			newSrv := &corefile.Server{
+				DomPorts: s.DomPorts,
+				Plugins:  newPlugs,
+			}
+			newSrvs = append(newSrvs, newSrv)
+		}
+
+		cf = &corefile.Corefile{Servers: newSrvs}
+
+		if v == toCoreDNSVersion {
+			break
+		}
+		v = Versions[v].priorVersion
+	}
+	return cf.ToString(), nil
+}
+
+// Default returns true if the Corefile is the default for a given version of Kubernetes.
+// Or, if k8sVersion is empty, Default returns true if the Corefile is the default for any version of Kubernetes.
+func Default(k8sVersion, corefileStr string) bool {
+	cf, err := corefile.New(corefileStr)
+	if err != nil {
+		return false
+	}
+NextVersion:
+	for _, v := range Versions {
+		for _, release := range v.k8sReleases {
+			if k8sVersion != "" && k8sVersion != release {
+				continue
+			}
+		}
+		defCf, err := corefile.New(v.defaultConf)
+		if err != nil {
+			continue
+		}
+		// check corefile against k8s release default
+		if len(cf.Servers) != len(defCf.Servers) {
+			continue NextVersion
+		}
+		for _, s := range cf.Servers {
+			defS, found := s.FindMatch(defCf.Servers)
+			if !found {
+				continue NextVersion
+			}
+			if len(s.Plugins) != len(defS.Plugins) {
+				continue NextVersion
+			}
+			for _, p := range s.Plugins {
+				defP, found := p.FindMatch(defS.Plugins)
+				if !found {
+					continue NextVersion
+				}
+				if len(p.Options) != len(defP.Options) {
+					continue NextVersion
+				}
+				for _, o := range p.Options {
+					_, found := o.FindMatch(defP.Options)
+					if !found {
+						continue NextVersion
+					}
+				}
+			}
+		}
+		return true
+	}
+	return false
+}
+
+// Released returns true if dockerImageSHA matches any released image of CoreDNS.
+func Released(dockerImageSHA string) bool {
+	for _, v := range Versions {
+		if v.dockerImageSHA == dockerImageSHA {
+			return true
+		}
+	}
+	return false
+}
+
+// ValidVersions returns a list of all versions defined
+func ValidVersions() []string {
+	var vStrs []string
+	for vStr := range Versions {
+		vStrs = append(vStrs, vStr)
+	}
+	sort.Strings(vStrs)
+	return vStrs
+}
+
+func validateVersion(fromCoreDNSVersion string) error {
+	if _, ok := Versions[fromCoreDNSVersion]; !ok {
+		return fmt.Errorf("start version '%v' not supported", fromCoreDNSVersion)
+	}
+	return nil
+}
+
+func validUpMigration(fromCoreDNSVersion, toCoreDNSVersion string) error {
+	err := validateVersion(fromCoreDNSVersion)
+	if err != nil {
+		return err
+	}
+	for next := Versions[fromCoreDNSVersion].nextVersion; next != ""; next = Versions[next].nextVersion {
+		if next != toCoreDNSVersion {
+			continue
+		}
+		return nil
+	}
+	return fmt.Errorf("cannot migrate up to '%v' from '%v'", toCoreDNSVersion, fromCoreDNSVersion)
+}
+
+func validDownMigration(fromCoreDNSVersion, toCoreDNSVersion string) error {
+	err := validateVersion(fromCoreDNSVersion)
+	if err != nil {
+		return err
+	}
+	for prior := Versions[fromCoreDNSVersion].priorVersion; prior != ""; prior = Versions[prior].priorVersion {
+		if prior != toCoreDNSVersion {
+			continue
+		}
+		return nil
+	}
+	return fmt.Errorf("cannot migrate down to '%v' from '%v'", toCoreDNSVersion, fromCoreDNSVersion)
+}

vendor/github.com/coredns/corefile-migration/migration/notice.go

@@ -0,0 +1,48 @@
+package migration
+
+import "fmt"
+
+// Notice is a migration warning
+type Notice struct {
+	Plugin     string
+	Option     string
+	Severity   string // 'deprecated', 'removed', or 'unsupported'
+	ReplacedBy string
+	Additional string
+	Version    string
+}
+
+func (n *Notice) ToString() string {
+	s := ""
+	if n.Option == "" {
+		s += fmt.Sprintf(`Plugin "%v" `, n.Plugin)
+	} else {
+		s += fmt.Sprintf(`Option "%v" in plugin "%v" `, n.Option, n.Plugin)
+	}
+	if n.Severity == unsupported {
+		s += "is unsupported by this migration tool in " + n.Version + "."
+	} else if n.Severity == newdefault {
+		s += "is added as a default in " + n.Version + "."
+	} else {
+		s += "is " + n.Severity + " in " + n.Version + "."
+	}
+	if n.ReplacedBy != "" {
+		s += fmt.Sprintf(` It is replaced by "%v".`, n.ReplacedBy)
+	}
+	if n.Additional != "" {
+		s += " " + n.Additional
+	}
+	return s
+}
+
+const (
+	// The following statuses are used to indicate the state of support/deprecation in a given release.
+	deprecated  = "deprecated"  // deprecated, but still completely functional
+	ignored     = "ignored"     // if included in the corefile, it will be ignored by CoreDNS
+	removed     = "removed"     // completely removed from CoreDNS, and would cause CoreDNS to exit if present in the Corefile
+	newdefault  = "newdefault"  // added to the default corefile.  CoreDNS may not function properly if it is not present in the corefile.
+	unsupported = "unsupported" // the plugin/option is not supported by the migration tool
+
+	// The following statuses are used for selecting/filtering notifications
+	all = "all" // show all statuses
+)

vendor/github.com/spf13/cobra/.gitignore

@@ -34,3 +34,5 @@ tags
 *.exe
 
 cobra.test
+
+.idea/*

vendor/github.com/spf13/cobra/BUILD

@@ -9,6 +9,8 @@ go_library(
         "command.go",
         "command_notwin.go",
         "command_win.go",
+        "powershell_completions.go",
+        "shell_completions.go",
         "zsh_completions.go",
     ],
     importmap = "k8s.io/kubernetes/vendor/github.com/spf13/cobra",

vendor/github.com/spf13/cobra/README.md

@@ -23,6 +23,7 @@ Many of the most widely used Go projects are built using Cobra, such as:
 [Istio](https://istio.io),
 [Prototool](https://github.com/uber/prototool),
 [mattermost-server](https://github.com/mattermost/mattermost-server),
+[Gardener](https://github.com/gardener/gardenctl),
 etc.
 
 [![Build Status](https://travis-ci.org/spf13/cobra.svg "Travis CI status")](https://travis-ci.org/spf13/cobra)
@@ -48,6 +49,7 @@ etc.
   * [Suggestions when "unknown command" happens](#suggestions-when-unknown-command-happens)
   * [Generating documentation for your command](#generating-documentation-for-your-command)
   * [Generating bash completions](#generating-bash-completions)
+  * [Generating zsh completions](#generating-zsh-completions)
 - [Contributing](#contributing)
 - [License](#license)
 
@@ -336,7 +338,7 @@ rootCmd.PersistentFlags().BoolVarP(&Verbose, "verbose", "v", false, "verbose out
 A flag can also be assigned locally which will only apply to that specific command.
 
 ```go
-rootCmd.Flags().StringVarP(&Source, "source", "s", "", "Source directory to read from")
+localCmd.Flags().StringVarP(&Source, "source", "s", "", "Source directory to read from")
 ```
 
 ### Local Flag on Parent Commands
@@ -719,6 +721,11 @@ Cobra can generate documentation based on subcommands, flags, etc. in the follow
 
 Cobra can generate a bash-completion file. If you add more information to your command, these completions can be amazingly powerful and flexible.  Read more about it in [Bash Completions](bash_completions.md).
 
+## Generating zsh completions
+
+Cobra can generate zsh-completion file. Read more about it in
+[Zsh Completions](zsh_completions.md).
+
 # Contributing
 
 1. Fork it

vendor/github.com/spf13/cobra/bash_completions.go

@@ -545,51 +545,3 @@ func (c *Command) GenBashCompletionFile(filename string) error {
 
 	return c.GenBashCompletion(outFile)
 }
-
-// MarkFlagRequired adds the BashCompOneRequiredFlag annotation to the named flag if it exists,
-// and causes your command to report an error if invoked without the flag.
-func (c *Command) MarkFlagRequired(name string) error {
-	return MarkFlagRequired(c.Flags(), name)
-}
-
-// MarkPersistentFlagRequired adds the BashCompOneRequiredFlag annotation to the named persistent flag if it exists,
-// and causes your command to report an error if invoked without the flag.
-func (c *Command) MarkPersistentFlagRequired(name string) error {
-	return MarkFlagRequired(c.PersistentFlags(), name)
-}
-
-// MarkFlagRequired adds the BashCompOneRequiredFlag annotation to the named flag if it exists,
-// and causes your command to report an error if invoked without the flag.
-func MarkFlagRequired(flags *pflag.FlagSet, name string) error {
-	return flags.SetAnnotation(name, BashCompOneRequiredFlag, []string{"true"})
-}
-
-// MarkFlagFilename adds the BashCompFilenameExt annotation to the named flag, if it exists.
-// Generated bash autocompletion will select filenames for the flag, limiting to named extensions if provided.
-func (c *Command) MarkFlagFilename(name string, extensions ...string) error {
-	return MarkFlagFilename(c.Flags(), name, extensions...)
-}
-
-// MarkFlagCustom adds the BashCompCustom annotation to the named flag, if it exists.
-// Generated bash autocompletion will call the bash function f for the flag.
-func (c *Command) MarkFlagCustom(name string, f string) error {
-	return MarkFlagCustom(c.Flags(), name, f)
-}
-
-// MarkPersistentFlagFilename adds the BashCompFilenameExt annotation to the named persistent flag, if it exists.
-// Generated bash autocompletion will select filenames for the flag, limiting to named extensions if provided.
-func (c *Command) MarkPersistentFlagFilename(name string, extensions ...string) error {
-	return MarkFlagFilename(c.PersistentFlags(), name, extensions...)
-}
-
-// MarkFlagFilename adds the BashCompFilenameExt annotation to the named flag in the flag set, if it exists.
-// Generated bash autocompletion will select filenames for the flag, limiting to named extensions if provided.
-func MarkFlagFilename(flags *pflag.FlagSet, name string, extensions ...string) error {
-	return flags.SetAnnotation(name, BashCompFilenameExt, extensions)
-}
-
-// MarkFlagCustom adds the BashCompCustom annotation to the named flag in the flag set, if it exists.
-// Generated bash autocompletion will call the bash function f for the flag.
-func MarkFlagCustom(flags *pflag.FlagSet, name string, f string) error {
-	return flags.SetAnnotation(name, BashCompCustom, []string{f})
-}

vendor/github.com/spf13/cobra/command.go

@@ -177,8 +177,6 @@ type Command struct {
 	// that we can use on every pflag set and children commands
 	globNormFunc func(f *flag.FlagSet, name string) flag.NormalizedName
 
-	// output is an output writer defined by user.
-	output io.Writer
 	// usageFunc is usage func defined by user.
 	usageFunc func(*Command) error
 	// usageTemplate is usage template defined by user.
@@ -195,6 +193,13 @@ type Command struct {
 	helpCommand *Command
 	// versionTemplate is the version template defined by user.
 	versionTemplate string
+
+	// inReader is a reader defined by the user that replaces stdin
+	inReader io.Reader
+	// outWriter is a writer defined by the user that replaces stdout
+	outWriter io.Writer
+	// errWriter is a writer defined by the user that replaces stderr
+	errWriter io.Writer
 }
 
 // SetArgs sets arguments for the command. It is set to os.Args[1:] by default, if desired, can be overridden
@@ -205,8 +210,28 @@ func (c *Command) SetArgs(a []string) {
 
 // SetOutput sets the destination for usage and error messages.
 // If output is nil, os.Stderr is used.
+// Deprecated: Use SetOut and/or SetErr instead
 func (c *Command) SetOutput(output io.Writer) {
-	c.output = output
+	c.outWriter = output
+	c.errWriter = output
+}
+
+// SetOut sets the destination for usage messages.
+// If newOut is nil, os.Stdout is used.
+func (c *Command) SetOut(newOut io.Writer) {
+	c.outWriter = newOut
+}
+
+// SetErr sets the destination for error messages.
+// If newErr is nil, os.Stderr is used.
+func (c *Command) SetErr(newErr io.Writer) {
+	c.errWriter = newErr
+}
+
+// SetOut sets the source for input data
+// If newIn is nil, os.Stdin is used.
+func (c *Command) SetIn(newIn io.Reader) {
+	c.inReader = newIn
 }
 
 // SetUsageFunc sets usage function. Usage can be defined by application.
@@ -267,9 +292,19 @@ func (c *Command) OutOrStderr() io.Writer {
 	return c.getOut(os.Stderr)
 }
 
+// ErrOrStderr returns output to stderr
+func (c *Command) ErrOrStderr() io.Writer {
+	return c.getErr(os.Stderr)
+}
+
+// ErrOrStderr returns output to stderr
+func (c *Command) InOrStdin() io.Reader {
+	return c.getIn(os.Stdin)
+}
+
 func (c *Command) getOut(def io.Writer) io.Writer {
-	if c.output != nil {
+	if c.outWriter != nil {
-		return c.output
+		return c.outWriter
 	}
 	if c.HasParent() {
 		return c.parent.getOut(def)
@@ -277,6 +312,26 @@ func (c *Command) getOut(def io.Writer) io.Writer {
 	return def
 }
 
+func (c *Command) getErr(def io.Writer) io.Writer {
+	if c.errWriter != nil {
+		return c.errWriter
+	}
+	if c.HasParent() {
+		return c.parent.getErr(def)
+	}
+	return def
+}
+
+func (c *Command) getIn(def io.Reader) io.Reader {
+	if c.inReader != nil {
+		return c.inReader
+	}
+	if c.HasParent() {
+		return c.parent.getIn(def)
+	}
+	return def
+}
+
 // UsageFunc returns either the function set by SetUsageFunc for this command
 // or a parent, or it returns a default usage function.
 func (c *Command) UsageFunc() (f func(*Command) error) {
@@ -329,13 +384,22 @@ func (c *Command) Help() error {
 	return nil
 }
 
-// UsageString return usage string.
+// UsageString returns usage string.
 func (c *Command) UsageString() string {
-	tmpOutput := c.output
+	// Storing normal writers
+	tmpOutput := c.outWriter
+	tmpErr := c.errWriter
+
 	bb := new(bytes.Buffer)
-	c.SetOutput(bb)
+	c.outWriter = bb
+	c.errWriter = bb
+
 	c.Usage()
-	c.output = tmpOutput
+
+	// Setting things back to normal
+	c.outWriter = tmpOutput
+	c.errWriter = tmpErr
+
 	return bb.String()
 }
 
@@ -1068,6 +1132,21 @@ func (c *Command) Printf(format string, i ...interface{}) {
 	c.Print(fmt.Sprintf(format, i...))
 }
 
+// PrintErr is a convenience method to Print to the defined Err output, fallback to Stderr if not set.
+func (c *Command) PrintErr(i ...interface{}) {
+	fmt.Fprint(c.ErrOrStderr(), i...)
+}
+
+// PrintErrln is a convenience method to Println to the defined Err output, fallback to Stderr if not set.
+func (c *Command) PrintErrln(i ...interface{}) {
+	c.Print(fmt.Sprintln(i...))
+}
+
+// PrintErrf is a convenience method to Printf to the defined Err output, fallback to Stderr if not set.
+func (c *Command) PrintErrf(format string, i ...interface{}) {
+	c.Print(fmt.Sprintf(format, i...))
+}
+
 // CommandPath returns the full path to this command.
 func (c *Command) CommandPath() string {
 	if c.HasParent() {

vendor/github.com/spf13/cobra/powershell_completions.go

@@ -0,0 +1,100 @@
+// PowerShell completions are based on the amazing work from clap:
+// https://github.com/clap-rs/clap/blob/3294d18efe5f264d12c9035f404c7d189d4824e1/src/completions/powershell.rs
+//
+// The generated scripts require PowerShell v5.0+ (which comes Windows 10, but
+// can be downloaded separately for windows 7 or 8.1).
+
+package cobra
+
+import (
+	"bytes"
+	"fmt"
+	"io"
+	"os"
+	"strings"
+
+	"github.com/spf13/pflag"
+)
+
+var powerShellCompletionTemplate = `using namespace System.Management.Automation
+using namespace System.Management.Automation.Language
+Register-ArgumentCompleter -Native -CommandName '%s' -ScriptBlock {
+    param($wordToComplete, $commandAst, $cursorPosition)
+    $commandElements = $commandAst.CommandElements
+    $command = @(
+        '%s'
+        for ($i = 1; $i -lt $commandElements.Count; $i++) {
+            $element = $commandElements[$i]
+            if ($element -isnot [StringConstantExpressionAst] -or
+                $element.StringConstantType -ne [StringConstantType]::BareWord -or
+                $element.Value.StartsWith('-')) {
+                break
+            }
+            $element.Value
+        }
+    ) -join ';'
+    $completions = @(switch ($command) {%s
+    })
+    $completions.Where{ $_.CompletionText -like "$wordToComplete*" } |
+        Sort-Object -Property ListItemText
+}`
+
+func generatePowerShellSubcommandCases(out io.Writer, cmd *Command, previousCommandName string) {
+	var cmdName string
+	if previousCommandName == "" {
+		cmdName = cmd.Name()
+	} else {
+		cmdName = fmt.Sprintf("%s;%s", previousCommandName, cmd.Name())
+	}
+
+	fmt.Fprintf(out, "\n        '%s' {", cmdName)
+
+	cmd.Flags().VisitAll(func(flag *pflag.Flag) {
+		if nonCompletableFlag(flag) {
+			return
+		}
+		usage := escapeStringForPowerShell(flag.Usage)
+		if len(flag.Shorthand) > 0 {
+			fmt.Fprintf(out, "\n            [CompletionResult]::new('-%s', '%s', [CompletionResultType]::ParameterName, '%s')", flag.Shorthand, flag.Shorthand, usage)
+		}
+		fmt.Fprintf(out, "\n            [CompletionResult]::new('--%s', '%s', [CompletionResultType]::ParameterName, '%s')", flag.Name, flag.Name, usage)
+	})
+
+	for _, subCmd := range cmd.Commands() {
+		usage := escapeStringForPowerShell(subCmd.Short)
+		fmt.Fprintf(out, "\n            [CompletionResult]::new('%s', '%s', [CompletionResultType]::ParameterValue, '%s')", subCmd.Name(), subCmd.Name(), usage)
+	}
+
+	fmt.Fprint(out, "\n            break\n        }")
+
+	for _, subCmd := range cmd.Commands() {
+		generatePowerShellSubcommandCases(out, subCmd, cmdName)
+	}
+}
+
+func escapeStringForPowerShell(s string) string {
+	return strings.Replace(s, "'", "''", -1)
+}
+
+// GenPowerShellCompletion generates PowerShell completion file and writes to the passed writer.
+func (c *Command) GenPowerShellCompletion(w io.Writer) error {
+	buf := new(bytes.Buffer)
+
+	var subCommandCases bytes.Buffer
+	generatePowerShellSubcommandCases(&subCommandCases, c, "")
+	fmt.Fprintf(buf, powerShellCompletionTemplate, c.Name(), c.Name(), subCommandCases.String())
+
+	_, err := buf.WriteTo(w)
+	return err
+}
+
+// GenPowerShellCompletionFile generates PowerShell completion file.
+func (c *Command) GenPowerShellCompletionFile(filename string) error {
+	outFile, err := os.Create(filename)
+	if err != nil {
+		return err
+	}
+	defer outFile.Close()
+
+	return c.GenPowerShellCompletion(outFile)
+}

vendor/github.com/spf13/cobra/powershell_completions.md

@@ -0,0 +1,14 @@
+# Generating PowerShell Completions For Your Own cobra.Command
+
+Cobra can generate PowerShell completion scripts. Users need PowerShell version 5.0 or above, which comes with Windows 10 and can be downloaded separately for Windows 7 or 8.1. They can then write the completions to a file and source this file from their PowerShell profile, which is referenced by the `$Profile` environment variable. See `Get-Help about_Profiles` for more info about PowerShell profiles.
+
+# What's supported
+
+- Completion for subcommands using their `.Short` description
+- Completion for non-hidden flags using their `.Name` and `.Shorthand`
+
+# What's not yet supported
+
+- Command aliases
+- Required, filename or custom flags (they will work like normal flags)
+- Custom completion scripts

vendor/github.com/spf13/cobra/shell_completions.go

@@ -0,0 +1,85 @@
+package cobra
+
+import (
+	"github.com/spf13/pflag"
+)
+
+// MarkFlagRequired adds the BashCompOneRequiredFlag annotation to the named flag if it exists,
+// and causes your command to report an error if invoked without the flag.
+func (c *Command) MarkFlagRequired(name string) error {
+	return MarkFlagRequired(c.Flags(), name)
+}
+
+// MarkPersistentFlagRequired adds the BashCompOneRequiredFlag annotation to the named persistent flag if it exists,
+// and causes your command to report an error if invoked without the flag.
+func (c *Command) MarkPersistentFlagRequired(name string) error {
+	return MarkFlagRequired(c.PersistentFlags(), name)
+}
+
+// MarkFlagRequired adds the BashCompOneRequiredFlag annotation to the named flag if it exists,
+// and causes your command to report an error if invoked without the flag.
+func MarkFlagRequired(flags *pflag.FlagSet, name string) error {
+	return flags.SetAnnotation(name, BashCompOneRequiredFlag, []string{"true"})
+}
+
+// MarkFlagFilename adds the BashCompFilenameExt annotation to the named flag, if it exists.
+// Generated bash autocompletion will select filenames for the flag, limiting to named extensions if provided.
+func (c *Command) MarkFlagFilename(name string, extensions ...string) error {
+	return MarkFlagFilename(c.Flags(), name, extensions...)
+}
+
+// MarkFlagCustom adds the BashCompCustom annotation to the named flag, if it exists.
+// Generated bash autocompletion will call the bash function f for the flag.
+func (c *Command) MarkFlagCustom(name string, f string) error {
+	return MarkFlagCustom(c.Flags(), name, f)
+}
+
+// MarkPersistentFlagFilename instructs the various shell completion
+// implementations to limit completions for this persistent flag to the
+// specified extensions (patterns).
+//
+// Shell Completion compatibility matrix: bash, zsh
+func (c *Command) MarkPersistentFlagFilename(name string, extensions ...string) error {
+	return MarkFlagFilename(c.PersistentFlags(), name, extensions...)
+}
+
+// MarkFlagFilename instructs the various shell completion implementations to
+// limit completions for this flag to the specified extensions (patterns).
+//
+// Shell Completion compatibility matrix: bash, zsh
+func MarkFlagFilename(flags *pflag.FlagSet, name string, extensions ...string) error {
+	return flags.SetAnnotation(name, BashCompFilenameExt, extensions)
+}
+
+// MarkFlagCustom instructs the various shell completion implementations to
+// limit completions for this flag to the specified extensions (patterns).
+//
+// Shell Completion compatibility matrix: bash, zsh
+func MarkFlagCustom(flags *pflag.FlagSet, name string, f string) error {
+	return flags.SetAnnotation(name, BashCompCustom, []string{f})
+}
+
+// MarkFlagDirname instructs the various shell completion implementations to
+// complete only directories with this named flag.
+//
+// Shell Completion compatibility matrix: zsh
+func (c *Command) MarkFlagDirname(name string) error {
+	return MarkFlagDirname(c.Flags(), name)
+}
+
+// MarkPersistentFlagDirname instructs the various shell completion
+// implementations to complete only directories with this persistent named flag.
+//
+// Shell Completion compatibility matrix: zsh
+func (c *Command) MarkPersistentFlagDirname(name string) error {
+	return MarkFlagDirname(c.PersistentFlags(), name)
+}
+
+// MarkFlagDirname instructs the various shell completion implementations to
+// complete only directories with this specified flag.
+//
+// Shell Completion compatibility matrix: zsh
+func MarkFlagDirname(flags *pflag.FlagSet, name string) error {
+	zshPattern := "-(/)"
+	return flags.SetAnnotation(name, zshCompDirname, []string{zshPattern})
+}

vendor/github.com/spf13/cobra/zsh_completions.go

@@ -1,13 +1,102 @@
 package cobra
 
 import (
-	"bytes"
+	"encoding/json"
 	"fmt"
 	"io"
 	"os"
+	"sort"
 	"strings"
+	"text/template"
+
+	"github.com/spf13/pflag"
 )
 
+const (
+	zshCompArgumentAnnotation   = "cobra_annotations_zsh_completion_argument_annotation"
+	zshCompArgumentFilenameComp = "cobra_annotations_zsh_completion_argument_file_completion"
+	zshCompArgumentWordComp     = "cobra_annotations_zsh_completion_argument_word_completion"
+	zshCompDirname              = "cobra_annotations_zsh_dirname"
+)
+
+var (
+	zshCompFuncMap = template.FuncMap{
+		"genZshFuncName":              zshCompGenFuncName,
+		"extractFlags":                zshCompExtractFlag,
+		"genFlagEntryForZshArguments": zshCompGenFlagEntryForArguments,
+		"extractArgsCompletions":      zshCompExtractArgumentCompletionHintsForRendering,
+	}
+	zshCompletionText = `
+{{/* should accept Command (that contains subcommands) as parameter */}}
+{{define "argumentsC" -}}
+{{ $cmdPath := genZshFuncName .}}
+function {{$cmdPath}} {
+  local -a commands
+
+  _arguments -C \{{- range extractFlags .}}
+    {{genFlagEntryForZshArguments .}} \{{- end}}
+    "1: :->cmnds" \
+    "*::arg:->args"
+
+  case $state in
+  cmnds)
+    commands=({{range .Commands}}{{if not .Hidden}}
+      "{{.Name}}:{{.Short}}"{{end}}{{end}}
+    )
+    _describe "command" commands
+    ;;
+  esac
+
+  case "$words[1]" in {{- range .Commands}}{{if not .Hidden}}
+  {{.Name}})
+    {{$cmdPath}}_{{.Name}}
+    ;;{{end}}{{end}}
+  esac
+}
+{{range .Commands}}{{if not .Hidden}}
+{{template "selectCmdTemplate" .}}
+{{- end}}{{end}}
+{{- end}}
+
+{{/* should accept Command without subcommands as parameter */}}
+{{define "arguments" -}}
+function {{genZshFuncName .}} {
+{{"  _arguments"}}{{range extractFlags .}} \
+    {{genFlagEntryForZshArguments . -}}
+{{end}}{{range extractArgsCompletions .}} \
+    {{.}}{{end}}
+}
+{{end}}
+
+{{/* dispatcher for commands with or without subcommands */}}
+{{define "selectCmdTemplate" -}}
+{{if .Hidden}}{{/* ignore hidden*/}}{{else -}}
+{{if .Commands}}{{template "argumentsC" .}}{{else}}{{template "arguments" .}}{{end}}
+{{- end}}
+{{- end}}
+
+{{/* template entry point */}}
+{{define "Main" -}}
+#compdef _{{.Name}} {{.Name}}
+
+{{template "selectCmdTemplate" .}}
+{{end}}
+`
+)
+
+// zshCompArgsAnnotation is used to encode/decode zsh completion for
+// arguments to/from Command.Annotations.
+type zshCompArgsAnnotation map[int]zshCompArgHint
+
+type zshCompArgHint struct {
+	// Indicates the type of the completion to use. One of:
+	// zshCompArgumentFilenameComp or zshCompArgumentWordComp
+	Tipe string `json:"type"`
+
+	// A value for the type above (globs for file completion or words)
+	Options []string `json:"options"`
+}
+
 // GenZshCompletionFile generates zsh completion file.
 func (c *Command) GenZshCompletionFile(filename string) error {
 	outFile, err := os.Create(filename)
@@ -19,108 +108,229 @@ func (c *Command) GenZshCompletionFile(filename string) error {
 	return c.GenZshCompletion(outFile)
 }
 
-// GenZshCompletion generates a zsh completion file and writes to the passed writer.
+// GenZshCompletion generates a zsh completion file and writes to the passed
+// writer. The completion always run on the root command regardless of the
+// command it was called from.
 func (c *Command) GenZshCompletion(w io.Writer) error {
-	buf := new(bytes.Buffer)
+	tmpl, err := template.New("Main").Funcs(zshCompFuncMap).Parse(zshCompletionText)
-
+	if err != nil {
-	writeHeader(buf, c)
+		return fmt.Errorf("error creating zsh completion template: %v", err)
-	maxDepth := maxDepth(c)
-	writeLevelMapping(buf, maxDepth)
-	writeLevelCases(buf, maxDepth, c)
-
-	_, err := buf.WriteTo(w)
-	return err
-}
-
-func writeHeader(w io.Writer, cmd *Command) {
-	fmt.Fprintf(w, "#compdef %s\n\n", cmd.Name())
-}
-
-func maxDepth(c *Command) int {
-	if len(c.Commands()) == 0 {
-		return 0
 	}
-	maxDepthSub := 0
+	return tmpl.Execute(w, c.Root())
-	for _, s := range c.Commands() {
+}
-		subDepth := maxDepth(s)
+
-		if subDepth > maxDepthSub {
+// MarkZshCompPositionalArgumentFile marks the specified argument (first
-			maxDepthSub = subDepth
+// argument is 1) as completed by file selection. patterns (e.g. "*.txt") are
+// optional - if not provided the completion will search for all files.
+func (c *Command) MarkZshCompPositionalArgumentFile(argPosition int, patterns ...string) error {
+	if argPosition < 1 {
+		return fmt.Errorf("Invalid argument position (%d)", argPosition)
+	}
+	annotation, err := c.zshCompGetArgsAnnotations()
+	if err != nil {
+		return err
+	}
+	if c.zshcompArgsAnnotationnIsDuplicatePosition(annotation, argPosition) {
+		return fmt.Errorf("Duplicate annotation for positional argument at index %d", argPosition)
+	}
+	annotation[argPosition] = zshCompArgHint{
+		Tipe:    zshCompArgumentFilenameComp,
+		Options: patterns,
+	}
+	return c.zshCompSetArgsAnnotations(annotation)
+}
+
+// MarkZshCompPositionalArgumentWords marks the specified positional argument
+// (first argument is 1) as completed by the provided words. At east one word
+// must be provided, spaces within words will be offered completion with
+// "word\ word".
+func (c *Command) MarkZshCompPositionalArgumentWords(argPosition int, words ...string) error {
+	if argPosition < 1 {
+		return fmt.Errorf("Invalid argument position (%d)", argPosition)
+	}
+	if len(words) == 0 {
+		return fmt.Errorf("Trying to set empty word list for positional argument %d", argPosition)
+	}
+	annotation, err := c.zshCompGetArgsAnnotations()
+	if err != nil {
+		return err
+	}
+	if c.zshcompArgsAnnotationnIsDuplicatePosition(annotation, argPosition) {
+		return fmt.Errorf("Duplicate annotation for positional argument at index %d", argPosition)
+	}
+	annotation[argPosition] = zshCompArgHint{
+		Tipe:    zshCompArgumentWordComp,
+		Options: words,
+	}
+	return c.zshCompSetArgsAnnotations(annotation)
+}
+
+func zshCompExtractArgumentCompletionHintsForRendering(c *Command) ([]string, error) {
+	var result []string
+	annotation, err := c.zshCompGetArgsAnnotations()
+	if err != nil {
+		return nil, err
+	}
+	for k, v := range annotation {
+		s, err := zshCompRenderZshCompArgHint(k, v)
+		if err != nil {
+			return nil, err
+		}
+		result = append(result, s)
+	}
+	if len(c.ValidArgs) > 0 {
+		if _, positionOneExists := annotation[1]; !positionOneExists {
+			s, err := zshCompRenderZshCompArgHint(1, zshCompArgHint{
+				Tipe:    zshCompArgumentWordComp,
+				Options: c.ValidArgs,
+			})
+			if err != nil {
+				return nil, err
+			}
+			result = append(result, s)
 		}
 	}
-	return 1 + maxDepthSub
+	sort.Strings(result)
+	return result, nil
 }
 
-func writeLevelMapping(w io.Writer, numLevels int) {
+func zshCompRenderZshCompArgHint(i int, z zshCompArgHint) (string, error) {
-	fmt.Fprintln(w, `_arguments \`)
+	switch t := z.Tipe; t {
-	for i := 1; i <= numLevels; i++ {
+	case zshCompArgumentFilenameComp:
-		fmt.Fprintf(w, `  '%d: :->level%d' \`, i, i)
+		var globs []string
-		fmt.Fprintln(w)
+		for _, g := range z.Options {
-	}
+			globs = append(globs, fmt.Sprintf(`-g "%s"`, g))
-	fmt.Fprintf(w, `  '%d: :%s'`, numLevels+1, "_files")
-	fmt.Fprintln(w)
-}
-
-func writeLevelCases(w io.Writer, maxDepth int, root *Command) {
-	fmt.Fprintln(w, "case $state in")
-	defer fmt.Fprintln(w, "esac")
-
-	for i := 1; i <= maxDepth; i++ {
-		fmt.Fprintf(w, "  level%d)\n", i)
-		writeLevel(w, root, i)
-		fmt.Fprintln(w, "  ;;")
-	}
-	fmt.Fprintln(w, "  *)")
-	fmt.Fprintln(w, "    _arguments '*: :_files'")
-	fmt.Fprintln(w, "  ;;")
-}
-
-func writeLevel(w io.Writer, root *Command, i int) {
-	fmt.Fprintf(w, "    case $words[%d] in\n", i)
-	defer fmt.Fprintln(w, "    esac")
-
-	commands := filterByLevel(root, i)
-	byParent := groupByParent(commands)
-
-	for p, c := range byParent {
-		names := names(c)
-		fmt.Fprintf(w, "      %s)\n", p)
-		fmt.Fprintf(w, "        _arguments '%d: :(%s)'\n", i, strings.Join(names, " "))
-		fmt.Fprintln(w, "      ;;")
-	}
-	fmt.Fprintln(w, "      *)")
-	fmt.Fprintln(w, "        _arguments '*: :_files'")
-	fmt.Fprintln(w, "      ;;")
-
-}
-
-func filterByLevel(c *Command, l int) []*Command {
-	cs := make([]*Command, 0)
-	if l == 0 {
-		cs = append(cs, c)
-		return cs
-	}
-	for _, s := range c.Commands() {
-		cs = append(cs, filterByLevel(s, l-1)...)
-	}
-	return cs
-}
-
-func groupByParent(commands []*Command) map[string][]*Command {
-	m := make(map[string][]*Command)
-	for _, c := range commands {
-		parent := c.Parent()
-		if parent == nil {
-			continue
 		}
-		m[parent.Name()] = append(m[parent.Name()], c)
+		return fmt.Sprintf(`'%d: :_files %s'`, i, strings.Join(globs, " ")), nil
+	case zshCompArgumentWordComp:
+		var words []string
+		for _, w := range z.Options {
+			words = append(words, fmt.Sprintf("%q", w))
+		}
+		return fmt.Sprintf(`'%d: :(%s)'`, i, strings.Join(words, " ")), nil
+	default:
+		return "", fmt.Errorf("Invalid zsh argument completion annotation: %s", t)
 	}
-	return m
 }
 
-func names(commands []*Command) []string {
+func (c *Command) zshcompArgsAnnotationnIsDuplicatePosition(annotation zshCompArgsAnnotation, position int) bool {
-	ns := make([]string, len(commands))
+	_, dup := annotation[position]
-	for i, c := range commands {
+	return dup
-		ns[i] = c.Name()
+}
-	}
+
-	return ns
+func (c *Command) zshCompGetArgsAnnotations() (zshCompArgsAnnotation, error) {
+	annotation := make(zshCompArgsAnnotation)
+	annotationString, ok := c.Annotations[zshCompArgumentAnnotation]
+	if !ok {
+		return annotation, nil
+	}
+	err := json.Unmarshal([]byte(annotationString), &annotation)
+	if err != nil {
+		return annotation, fmt.Errorf("Error unmarshaling zsh argument annotation: %v", err)
+	}
+	return annotation, nil
+}
+
+func (c *Command) zshCompSetArgsAnnotations(annotation zshCompArgsAnnotation) error {
+	jsn, err := json.Marshal(annotation)
+	if err != nil {
+		return fmt.Errorf("Error marshaling zsh argument annotation: %v", err)
+	}
+	if c.Annotations == nil {
+		c.Annotations = make(map[string]string)
+	}
+	c.Annotations[zshCompArgumentAnnotation] = string(jsn)
+	return nil
+}
+
+func zshCompGenFuncName(c *Command) string {
+	if c.HasParent() {
+		return zshCompGenFuncName(c.Parent()) + "_" + c.Name()
+	}
+	return "_" + c.Name()
+}
+
+func zshCompExtractFlag(c *Command) []*pflag.Flag {
+	var flags []*pflag.Flag
+	c.LocalFlags().VisitAll(func(f *pflag.Flag) {
+		if !f.Hidden {
+			flags = append(flags, f)
+		}
+	})
+	c.InheritedFlags().VisitAll(func(f *pflag.Flag) {
+		if !f.Hidden {
+			flags = append(flags, f)
+		}
+	})
+	return flags
+}
+
+// zshCompGenFlagEntryForArguments returns an entry that matches _arguments
+// zsh-completion parameters. It's too complicated to generate in a template.
+func zshCompGenFlagEntryForArguments(f *pflag.Flag) string {
+	if f.Name == "" || f.Shorthand == "" {
+		return zshCompGenFlagEntryForSingleOptionFlag(f)
+	}
+	return zshCompGenFlagEntryForMultiOptionFlag(f)
+}
+
+func zshCompGenFlagEntryForSingleOptionFlag(f *pflag.Flag) string {
+	var option, multiMark, extras string
+
+	if zshCompFlagCouldBeSpecifiedMoreThenOnce(f) {
+		multiMark = "*"
+	}
+
+	option = "--" + f.Name
+	if option == "--" {
+		option = "-" + f.Shorthand
+	}
+	extras = zshCompGenFlagEntryExtras(f)
+
+	return fmt.Sprintf(`'%s%s[%s]%s'`, multiMark, option, zshCompQuoteFlagDescription(f.Usage), extras)
+}
+
+func zshCompGenFlagEntryForMultiOptionFlag(f *pflag.Flag) string {
+	var options, parenMultiMark, curlyMultiMark, extras string
+
+	if zshCompFlagCouldBeSpecifiedMoreThenOnce(f) {
+		parenMultiMark = "*"
+		curlyMultiMark = "\\*"
+	}
+
+	options = fmt.Sprintf(`'(%s-%s %s--%s)'{%s-%s,%s--%s}`,
+		parenMultiMark, f.Shorthand, parenMultiMark, f.Name, curlyMultiMark, f.Shorthand, curlyMultiMark, f.Name)
+	extras = zshCompGenFlagEntryExtras(f)
+
+	return fmt.Sprintf(`%s'[%s]%s'`, options, zshCompQuoteFlagDescription(f.Usage), extras)
+}
+
+func zshCompGenFlagEntryExtras(f *pflag.Flag) string {
+	if f.NoOptDefVal != "" {
+		return ""
+	}
+
+	extras := ":" // allow options for flag (even without assistance)
+	for key, values := range f.Annotations {
+		switch key {
+		case zshCompDirname:
+			extras = fmt.Sprintf(":filename:_files -g %q", values[0])
+		case BashCompFilenameExt:
+			extras = ":filename:_files"
+			for _, pattern := range values {
+				extras = extras + fmt.Sprintf(` -g "%s"`, pattern)
+			}
+		}
+	}
+
+	return extras
+}
+
+func zshCompFlagCouldBeSpecifiedMoreThenOnce(f *pflag.Flag) bool {
+	return strings.Contains(f.Value.Type(), "Slice") ||
+		strings.Contains(f.Value.Type(), "Array")
+}
+
+func zshCompQuoteFlagDescription(s string) string {
+	return strings.Replace(s, "'", `'\''`, -1)
 }

vendor/github.com/spf13/cobra/zsh_completions.md

@@ -0,0 +1,39 @@
+## Generating Zsh Completion for your cobra.Command
+
+Cobra supports native Zsh completion generated from the root `cobra.Command`.
+The generated completion script should be put somewhere in your `$fpath` named
+`_<YOUR COMMAND>`.
+
+### What's Supported
+
+* Completion for all non-hidden subcommands using their `.Short` description.
+* Completion for all non-hidden flags using the following rules:
+  * Filename completion works by marking the flag with `cmd.MarkFlagFilename...`
+    family of commands.
+  * The requirement for argument to the flag is decided by the `.NoOptDefVal`
+    flag value - if it's empty then completion will expect an argument.
+  * Flags of one of the various `*Array` and `*Slice` types supports multiple
+    specifications (with or without argument depending on the specific type).
+* Completion of positional arguments using the following rules:
+  * Argument position for all options below starts at `1`. If argument position
+    `0` is requested it will raise an error.
+  * Use `command.MarkZshCompPositionalArgumentFile` to complete filenames. Glob
+    patterns (e.g. `"*.log"`) are optional - if not specified it will offer to
+    complete all file types.
+  * Use `command.MarkZshCompPositionalArgumentWords` to offer specific words for
+    completion. At least one word is required.
+  * It's possible to specify completion for some arguments and leave some
+    unspecified (e.g. offer words for second argument but nothing for first
+    argument). This will cause no completion for first argument but words
+    completion for second argument.
+  * If no argument completion was specified for 1st argument (but optionally was
+    specified for 2nd) and the command has `ValidArgs` it will be used as
+    completion options for 1st argument.
+  * Argument completions only offered for commands with no subcommands.
+
+### What's not yet Supported
+
+* Custom completion scripts are not supported yet (We should probably create zsh
+  specific one, doesn't make sense to re-use the bash one as the functions will
+  be different).
+* Whatever other feature you're looking for and doesn't exist :)

vendor/modules.txt

@@ -139,7 +139,7 @@ github.com/bazelbuild/buildtools/wspace
 github.com/beorn7/perks/quantile
 # github.com/blang/semver v3.5.0+incompatible => github.com/blang/semver v3.5.0+incompatible
 github.com/blang/semver
-# github.com/caddyserver/caddy v1.0.1 => github.com/caddyserver/caddy v1.0.1
+# github.com/caddyserver/caddy v1.0.3 => github.com/caddyserver/caddy v1.0.3
 github.com/caddyserver/caddy/caddyfile
 # github.com/cespare/prettybench v0.0.0-20150116022406-03b8cfe5406c => github.com/cespare/prettybench v0.0.0-20150116022406-03b8cfe5406c
 github.com/cespare/prettybench
@@ -190,6 +190,9 @@ github.com/containernetworking/cni/pkg/types
 github.com/containernetworking/cni/pkg/types/020
 github.com/containernetworking/cni/pkg/types/current
 github.com/containernetworking/cni/pkg/version
+# github.com/coredns/corefile-migration v1.0.2 => github.com/coredns/corefile-migration v1.0.2
+github.com/coredns/corefile-migration/migration
+github.com/coredns/corefile-migration/migration/corefile
 # github.com/coreos/bbolt v1.3.1-coreos.6 => github.com/coreos/bbolt v1.3.1-coreos.6
 github.com/coreos/bbolt
 # github.com/coreos/etcd v3.3.13+incompatible => github.com/coreos/etcd v3.3.13+incompatible
@@ -743,7 +746,7 @@ github.com/spf13/afero
 github.com/spf13/afero/mem
 # github.com/spf13/cast v1.3.0 => github.com/spf13/cast v1.3.0
 github.com/spf13/cast
-# github.com/spf13/cobra v0.0.4 => github.com/spf13/cobra v0.0.4
+# github.com/spf13/cobra v0.0.5 => github.com/spf13/cobra v0.0.5
 github.com/spf13/cobra
 github.com/spf13/cobra/doc
 # github.com/spf13/jwalterweatherman v1.1.0 => github.com/spf13/jwalterweatherman v1.1.0