list all currently supported Kubernetes versions

cmd/minikube/cmd/start.go

@@ -1585,10 +1585,10 @@ func validateKubernetesVersion(old *config.ClusterConfig) {
 		exitIfNotForced(reason.KubernetesTooNew, "Kubernetes {{.version}} is not supported by this release of minikube", out.V{"version": nvs})
 	}
 	if nvs.GT(newestVersion) {
-		out.WarningT("Specified Kubernetes version {{.specified}} is newer than the newest supported version: {{.newest}}", out.V{"specified": nvs, "newest": constants.NewestKubernetesVersion})
+		out.WarningT("Specified Kubernetes version {{.specified}} is newer than the newest supported version: {{.newest}}. Use `minikube version --kubernetes` for details.", out.V{"specified": nvs, "newest": constants.NewestKubernetesVersion})
 	}
 	if nvs.LT(oldestVersion) {
-		out.WarningT("Specified Kubernetes version {{.specified}} is less than the oldest supported version: {{.oldest}}", out.V{"specified": nvs, "oldest": constants.OldestKubernetesVersion})
+		out.WarningT("Specified Kubernetes version {{.specified}} is less than the oldest supported version: {{.oldest}}. Use `minikube version --kubernetes` for details.", out.V{"specified": nvs, "oldest": constants.OldestKubernetesVersion})
 		if !viper.GetBool(force) {
 			out.WarningT("You can force an unsupported Kubernetes version via the --force flag")
 		}

cmd/minikube/cmd/version.go

@@ -17,14 +17,19 @@ limitations under the License.
 package cmd
 
 import (
+	"context"
 	"encoding/json"
+	"fmt"
 	"os/exec"
 	"sort"
 	"strings"
 
+	"github.com/google/go-github/v43/github"
 	"github.com/spf13/cobra"
+	"golang.org/x/mod/semver"
 	"gopkg.in/yaml.v2"
 	"k8s.io/klog/v2"
+	"k8s.io/minikube/pkg/minikube/constants"
 	"k8s.io/minikube/pkg/minikube/exit"
 	"k8s.io/minikube/pkg/minikube/mustload"
 	"k8s.io/minikube/pkg/minikube/out"
@@ -36,6 +41,7 @@ var (
 	versionOutput          string
 	shortVersion           bool
 	listComponentsVersions bool
+	listKubernetesVersions bool
 )
 
 var versionCmd = &cobra.Command{
@@ -82,6 +88,16 @@ var versionCmd = &cobra.Command{
 
 		}
 
+		if listKubernetesVersions && !shortVersion {
+			skv, err := supportedKubernetesVersions(constants.OldestKubernetesVersion, constants.NewestKubernetesVersion, true)
+			if err != nil {
+				klog.Warningf("Unable to get supported Kubernetes versions: {{.error}}", out.V{"error": err})
+				data["supportedKubernetesVersions"] = fmt.Sprintf("[%s..%s]", constants.OldestKubernetesVersion, constants.NewestKubernetesVersion)
+			} else {
+				data["supportedKubernetesVersions"] = fmt.Sprintf("%v", skv)
+			}
+		}
+
 		switch versionOutput {
 		case "":
 			if !shortVersion {
@@ -125,8 +141,54 @@ var versionCmd = &cobra.Command{
 	},
 }
 
+// supportedKubernetesVersions returns reverse-sort supported Kubernetes releases from GitHub that are in [minver, maxver] range, optionally including prereleases, and any error occurred.
+func supportedKubernetesVersions(minver, maxver string, prereleases bool) (releases []string, err error) {
+	ghc := github.NewClient(nil)
+
+	if (minver != "" && !semver.IsValid(minver)) || (maxver != "" && !semver.IsValid(maxver)) {
+		return nil, fmt.Errorf("invalid release version(s) semver format: %q or %q", minver, maxver)
+	}
+	if minver != "" && maxver != "" && semver.Compare(minver, maxver) == 1 {
+		return nil, fmt.Errorf("invalid release versions range: min(%s) > max(%s)", minver, maxver)
+	}
+
+	opts := &github.ListOptions{PerPage: 100}
+	for (opts.Page+1)*100 <= 300 {
+		rls, resp, err := ghc.Repositories.ListReleases(context.Background(), "kubernetes", "kubernetes", opts)
+		if err != nil {
+			return nil, err
+		}
+		for _, r := range rls {
+			// extract version from release name (eg, "Kubernetes v1.22.0-beta.2" => "v1.22.0-beta.2")
+			v := r.GetName()
+			t := strings.Fields(v)
+			if len(t) > 1 {
+				v = t[len(t)-1]
+			}
+			if !semver.IsValid(v) {
+				continue
+			}
+			if !prereleases && r.GetPrerelease() {
+				continue
+			}
+			// skip out-of-range versions
+			if (minver != "" && semver.Compare(minver, v) == 1) || (maxver != "" && semver.Compare(v, maxver) == 1) {
+				continue
+			}
+			releases = append(releases, v)
+		}
+		if resp.NextPage == 0 {
+			break
+		}
+		opts.Page = resp.NextPage
+	}
+	sort.Slice(releases, func(i, j int) bool { return semver.Compare(releases[i], releases[j]) == 1 })
+	return releases, nil
+}
+
 func init() {
 	versionCmd.Flags().StringVarP(&versionOutput, "output", "o", "", "One of 'yaml' or 'json'.")
 	versionCmd.Flags().BoolVar(&shortVersion, "short", false, "Print just the version number.")
 	versionCmd.Flags().BoolVar(&listComponentsVersions, "components", false, "list versions of all components included with minikube. (the cluster must be running)")
+	versionCmd.Flags().BoolVar(&listKubernetesVersions, "kubernetes", false, "list all Kubernetes versions supported by this minikube version.")
 }

go.mod

@@ -100,6 +100,7 @@ require (
 require (
 	github.com/Xuanwo/go-locale v1.1.0
 	github.com/docker/go-connections v0.4.0
+	github.com/google/go-github/v43 v43.0.0
 	github.com/opencontainers/runc v1.0.2
 	github.com/santhosh-tekuri/jsonschema/v5 v5.0.0
 )
@@ -153,7 +154,7 @@ require (
 	github.com/golang/protobuf v1.5.2 // indirect
 	github.com/golang/snappy v0.0.3 // indirect
 	github.com/google/gnostic v0.5.7-v3refs // indirect
-	github.com/google/go-querystring v1.0.0 // indirect
+	github.com/google/go-querystring v1.1.0 // indirect
 	github.com/google/gofuzz v1.1.0 // indirect
 	github.com/googleapis/gax-go/v2 v2.3.0 // indirect
 	github.com/googleapis/go-type-adapters v1.0.0 // indirect

go.sum

@@ -576,8 +576,11 @@ github.com/google/go-containerregistry v0.6.0/go.mod h1:euCCtNbZ6tKqi1E72vwDj2xZ
 github.com/google/go-github v17.0.0+incompatible/go.mod h1:zLgOLi98H3fifZn+44m+umXrS52loVEgC2AApnigrVQ=
 github.com/google/go-github/v36 v36.0.0 h1:ndCzM616/oijwufI7nBRa+5eZHLldT+4yIB68ib5ogs=
 github.com/google/go-github/v36 v36.0.0/go.mod h1:LFlKC047IOqiglRGNqNb9s/iAPTnnjtlshm+bxp+kwk=
-github.com/google/go-querystring v1.0.0 h1:Xkwi/a1rcvNg1PPYe5vI8GbeBY/jrVuDX5ASuANWTrk=
+github.com/google/go-github/v43 v43.0.0 h1:y+GL7LIsAIF2NZlJ46ZoC/D1W1ivZasT0lnWHMYPZ+U=
+github.com/google/go-github/v43 v43.0.0/go.mod h1:ZkTvvmCXBvsfPpTHXnH/d2hP9Y0cTbvN9kr5xqyXOIc=
 github.com/google/go-querystring v1.0.0/go.mod h1:odCYkC5MyYFN7vkCjXpyrEuKhc/BUO6wN/zVPAxq5ck=
+github.com/google/go-querystring v1.1.0 h1:AnCroh3fv4ZBgVIf1Iwtovgjaw/GiKJo8M8yD/fhyJ8=
+github.com/google/go-querystring v1.1.0/go.mod h1:Kcdr2DB4koayq7X8pmAG4sNG59So17icRSOU623lUBU=
 github.com/google/gofuzz v1.0.0/go.mod h1:dBl0BpW6vV/+mYPU4Po3pmUjxk6FQPldtuIdl/M65Eg=
 github.com/google/gofuzz v1.1.0 h1:Hsa8mG0dQ46ij8Sl2AYJDUv1oA9/d6Vk+3LG99Oe02g=
 github.com/google/gofuzz v1.1.0/go.mod h1:dBl0BpW6vV/+mYPU4Po3pmUjxk6FQPldtuIdl/M65Eg=