add annotation to kubeconfig to identify contexts/clusters created by minikube

cmd/minikube/cmd/update-context.go

@@ -35,8 +35,9 @@ var updateContextCmd = &cobra.Command{
 	Run: func(cmd *cobra.Command, args []string) {
 		cname := ClusterFlagValue()
 		co := mustload.Running(cname)
+		//	cluster extension metada for kubeconfig
 
-		updated, err := kubeconfig.UpdateEndpoint(cname, co.CP.Hostname, co.CP.Port, kubeconfig.PathFromEnv())
+		updated, err := kubeconfig.UpdateEndpoint(cname, co.CP.Hostname, co.CP.Port, kubeconfig.PathFromEnv(), kubeconfig.NewExtension())
 		if err != nil {
 			exit.Error(reason.HostKubeconfigUpdate, "update config", err)
 		}

go.sum

@@ -988,8 +988,6 @@ github.com/tmc/grpc-websocket-proxy v0.0.0-20170815181823-89b8d40f7ca8/go.mod h1
 github.com/tmc/grpc-websocket-proxy v0.0.0-20190109142713-0ad062ec5ee5/go.mod h1:ncp9v5uamzpCO7NfCPTXjqaC+bZgJeR0sMTm6dMHP7U=
 github.com/ugorji/go v1.1.4/go.mod h1:uQMGLiO92mf5W77hV/PUCpI3pbzQx3CRekS0kk+RGrc=
 github.com/ugorji/go/codec v0.0.0-20181204163529-d75b2dcb6bc8/go.mod h1:VFNgLljTbGfSG7qAOspJ7OScBnGdDN/yBr0sguwnwf0=
-github.com/ulikunitz/xz v0.5.5 h1:pFrO0lVpTBXLpYw+pnLj6TbvHuyjXMfjGeCwSqCVwok=
-github.com/ulikunitz/xz v0.5.5/go.mod h1:2bypXElzHzzJZwzH67Y6wb67pO62Rzfn7BSiF4ABRW8=
 github.com/ulikunitz/xz v0.5.8 h1:ERv8V6GKqVi23rgu5cj9pVfVzJbOqAY2Ntl88O6c2nQ=
 github.com/ulikunitz/xz v0.5.8/go.mod h1:nbz6k7qbPmH4IRqmfOplQw/tblSgqTqBwxkY0oWt/14=
 github.com/ultraware/funlen v0.0.1/go.mod h1:Dp4UiAus7Wdb9KUZsYWZEWiRzGuM2kXM1lPbfaF6xhA=

pkg/minikube/bootstrapper/certs.go

@@ -99,6 +99,8 @@ func SetupCerts(cmd command.Runner, k8s config.KubernetesConfig, n config.Node)
 		ClientCertificate:    path.Join(vmpath.GuestKubernetesCertsDir, "apiserver.crt"),
 		ClientKey:            path.Join(vmpath.GuestKubernetesCertsDir, "apiserver.key"),
 		CertificateAuthority: path.Join(vmpath.GuestKubernetesCertsDir, "ca.crt"),
+		ExtensionContext:     kubeconfig.NewExtension(),
+		ExtensionCluster:     kubeconfig.NewExtension(),
 		KeepContext:          false,
 	}
 

pkg/minikube/bootstrapper/kubeadm/kubeadm.go

@@ -576,14 +576,14 @@ func (k *Bootstrapper) restartControlPlane(cfg config.ClusterConfig) error {
 		klog.Infof("restartCluster took %s", time.Since(start))
 	}()
 
-	version, err := util.ParseKubernetesVersion(cfg.KubernetesConfig.KubernetesVersion)
+	k8sVersion, err := util.ParseKubernetesVersion(cfg.KubernetesConfig.KubernetesVersion)
 	if err != nil {
 		return errors.Wrap(err, "parsing Kubernetes version")
 	}
 
 	phase := "alpha"
 	controlPlane := "controlplane"
-	if version.GTE(semver.MustParse("1.13.0")) {
+	if k8sVersion.GTE(semver.MustParse("1.13.0")) {
 		phase = "init"
 		controlPlane = "control-plane"
 	}
@@ -603,7 +603,7 @@ func (k *Bootstrapper) restartControlPlane(cfg config.ClusterConfig) error {
 	}
 
 	// Save the costly tax of reinstalling Kubernetes if the only issue is a missing kube context
-	_, err = kubeconfig.UpdateEndpoint(cfg.Name, hostname, port, kubeconfig.PathFromEnv())
+	_, err = kubeconfig.UpdateEndpoint(cfg.Name, hostname, port, kubeconfig.PathFromEnv(), kubeconfig.NewExtension())
 	if err != nil {
 		klog.Warningf("unable to update kubeconfig (cluster will likely require a reset): %v", err)
 	}

pkg/minikube/kubeconfig/extension.go

@@ -0,0 +1,66 @@
+/*
+Copyright 2021 The Kubernetes Authors All rights reserved.
+
+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 kubeconfig
+
+import (
+	"time"
+
+	"k8s.io/apimachinery/pkg/runtime"
+	"k8s.io/minikube/pkg/version"
+)
+
+// +k8s:deepcopy-gen:interfaces=k8s.io/apimachinery/pkg/runtime.Object
+// implementing the runtime.Object internally so we can write extensions to kubeconfig
+type Extension struct {
+	runtime.TypeMeta `json:",inline"`
+	Version          string `json:"version"`
+	Provider         string `json:"provider"`
+	LastUpdate       string `json:"last-update"`
+}
+
+// NewExtension returns a minikube formated kubeconfig's extension block to idenity clusters and contexts
+func NewExtension() *Extension {
+	return &Extension{
+		Provider: "minikube.sigs.k8s.io",
+		Version:  version.GetVersion(),
+		// time format matching other RFC in notify.go
+		LastUpdate: time.Now().Format(time.RFC1123)}
+}
+
+// DeepCopy is an autogenerated deepcopy function, copying the receiver, creating a new Extension.
+func (in *Extension) DeepCopy() *Extension {
+	if in == nil {
+		return nil
+	}
+	out := new(Extension)
+	in.DeepCopyInto(out)
+	return out
+}
+
+// DeepCopyObject is an autogenerated deepcopy function, copying the receiver, creating a new runtime.Object.
+func (in *Extension) DeepCopyObject() runtime.Object {
+	if c := in.DeepCopy(); c != nil {
+		return c
+	}
+	return nil
+}
+
+// DeepCopyInto is an autogenerated deepcopy function, copying the receiver, writing into out. in must be non-nil.
+func (in *Extension) DeepCopyInto(out *Extension) {
+	*out = *in
+	out.TypeMeta = in.TypeMeta
+}

pkg/minikube/kubeconfig/kubeconfig.go

@@ -105,7 +105,7 @@ func Endpoint(contextName string, configPath ...string) (string, int, error) {
 }
 
 // UpdateEndpoint overwrites the IP stored in kubeconfig with the provided IP.
-func UpdateEndpoint(contextName string, hostname string, port int, confpath string) (bool, error) {
+func UpdateEndpoint(contextName string, hostname string, port int, confpath string, ext *Extension) (bool, error) {
 	if hostname == "" {
 		return false, fmt.Errorf("empty ip")
 	}
@@ -136,6 +136,9 @@ func UpdateEndpoint(contextName string, hostname string, port int, confpath stri
 			CertificateAuthority: path.Join(gp, "ca.crt"),
 			KeepContext:          false,
 		}
+		if ext != nil {
+			kcs.ExtensionCluster = ext
+		}
 		err = PopulateFromSettings(kcs, cfg)
 		if err != nil {
 			return false, errors.Wrap(err, "populating kubeconfig")

pkg/minikube/kubeconfig/kubeconfig_test.go

@@ -410,7 +410,7 @@ func TestUpdateIP(t *testing.T) {
 			t.Parallel()
 			configFilename := tempFile(t, test.existing)
 			defer os.Remove(configFilename)
-			statusActual, err := UpdateEndpoint("minikube", test.hostname, test.port, configFilename)
+			statusActual, err := UpdateEndpoint("minikube", test.hostname, test.port, configFilename, nil)
 			if err != nil && !test.err {
 				t.Errorf("Got unexpected error: %v", err)
 			}
@@ -430,7 +430,7 @@ func TestUpdateIP(t *testing.T) {
 				t.Fatal(err)
 			}
 			if !configEquals(actual, expected) {
-				t.Fatal("configs did not match")
+				t.Fatalf("configs did not match: Actual:\n%+v\n Expected:\n%+v", actual, expected)
 			}
 		})
 

pkg/minikube/kubeconfig/settings.go

@@ -23,6 +23,7 @@ import (
 
 	"github.com/juju/mutex"
 	"github.com/pkg/errors"
+	"k8s.io/apimachinery/pkg/runtime"
 	"k8s.io/client-go/tools/clientcmd/api"
 	"k8s.io/klog/v2"
 	"k8s.io/minikube/pkg/util/lock"
@@ -54,6 +55,12 @@ type Settings struct {
 	// Should the certificate files be embedded instead of referenced by path
 	EmbedCerts bool
 
+	// Extension meta data for the cluster
+	ExtensionCluster *Extension
+
+	// Extension meta data for the cluster
+	ExtensionContext *Extension
+
 	// kubeConfigFile is the path where the kube config is stored
 	// Only access this with atomic ops
 	kubeConfigFile atomic.Value
@@ -83,6 +90,10 @@ func PopulateFromSettings(cfg *Settings, apiCfg *api.Config) error {
 	} else {
 		cluster.CertificateAuthority = cfg.CertificateAuthority
 	}
+
+	if cfg.ExtensionCluster != nil {
+		cluster.Extensions = map[string]runtime.Object{"cluster_info": cfg.ExtensionCluster.DeepCopy()}
+	}
 	apiCfg.Clusters[clusterName] = cluster
 
 	// user
@@ -109,6 +120,10 @@ func PopulateFromSettings(cfg *Settings, apiCfg *api.Config) error {
 	context.Cluster = cfg.ClusterName
 	context.Namespace = cfg.Namespace
 	context.AuthInfo = userName
+	if cfg.ExtensionContext != nil {
+		context.Extensions = map[string]runtime.Object{"context_info": cfg.ExtensionContext.DeepCopy()}
+	}
+
 	apiCfg.Contexts[contextName] = context
 
 	// Only set current context to minikube if the user has not used the keepContext flag
@@ -138,6 +153,9 @@ func Update(kcs *Settings) error {
 		return err
 	}
 
+	ext := NewExtension()
+	kcs.ExtensionCluster = ext
+	kcs.ExtensionContext = ext
 	err = PopulateFromSettings(kcs, kcfg)
 	if err != nil {
 		return err