--kubernetes-version add support for checking github k8s versions and exit nicely on error

cmd/minikube/cmd/config/kubernetes_version.go

@@ -17,6 +17,10 @@ limitations under the License.
 package config
 
 import (
+	"context"
+	"sort"
+
+	"github.com/google/go-github/github"
 	"golang.org/x/mod/semver"
 	"k8s.io/minikube/pkg/minikube/constants"
 )
@@ -34,3 +38,29 @@ func supportedKubernetesVersions() (releases []string) {
 	}
 	return releases
 }
+
+// GetGithubKubernetesVersions returns reverse-sort Kubernetes releases
+func GetGithubKubernetesVersions(ver string) ([]string, error) {
+	ghc := github.NewClient(nil)
+
+	opts := &github.ListOptions{PerPage: 100}
+	var releases []string
+	for {
+		rls, resp, err := ghc.Repositories.ListReleases(context.Background(), "kubernetes", "kubernetes", opts)
+		if err != nil {
+			return nil, err
+		}
+		for _, rl := range rls {
+			tag := rl.GetTagName()
+			if semver.IsValid(tag) {
+				releases = append(releases, tag)
+			}
+		}
+		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
+}

cmd/minikube/cmd/start.go

@@ -1771,6 +1771,21 @@ func validateKubernetesVersion(old *config.ClusterConfig) {
 	}
 	if nvs.GT(newestVersion) {
 		out.WarningT("Specified Kubernetes version {{.specified}} is newer than the newest supported version: {{.newest}}. Use `minikube config defaults kubernetes-version` for details.", out.V{"specified": nvs, "newest": constants.NewestKubernetesVersion})
+		if contains(constants.ValidKubernetesVersions, kubernetesVer) {
+			out.Styled(style.Check, "Kubernetes version {{.specified}} found in version list", out.V{"specified": nvs})
+		} else {
+			out.WarningT("Specified Kubernetes version {{.specified}} not found in Kubernetes version list. Searching the internet...", out.V{"specified": nvs})
+			k8sVersions, err := cmdcfg.GetGithubKubernetesVersions(kubernetesVer)
+			if err != nil && !viper.GetBool(force) {
+				exit.Error(reason.KubernetesNotConnect, "error fetching Kubernetes version list from Github", err)
+			}
+			if k8sVersions != nil && contains(k8sVersions, kubernetesVer) {
+				out.Styled(style.Check, "Kubernetes version {{.specified}} found in Github version list", out.V{"specified": nvs})
+			} else if !viper.GetBool(force) {
+				out.WarningT("Kubernetes version not found in Github version list. You can force a Kubernetes version via the --force flag")
+				exitIfNotForced(reason.KubernetesTooNew, "Kubernetes {{.version}} is not supported by this release of minikube", out.V{"version": nvs})
+			}
+		}
 	}
 	if nvs.LT(oldestVersion) {
 		out.WarningT("Specified Kubernetes version {{.specified}} is less than the oldest supported version: {{.oldest}}. Use `minikube config defaults kubernetes-version` for details.", out.V{"specified": nvs, "oldest": constants.OldestKubernetesVersion})
@@ -2007,3 +2022,14 @@ func isTwoDigitSemver(ver string) bool {
 	majorMinorOnly := regexp.MustCompile(`^(?P<major>0|[1-9]\d*)\.(?P<minor>0|[1-9]\d*)$`)
 	return majorMinorOnly.MatchString(ver)
 }
+
+// contains checks whether the parameter slice contains the parameter string
+func contains(sl []string, s string) bool {
+	for _, k := range sl {
+		if s == k {
+			return true
+		}
+
+	}
+	return false
+}

go.mod

@@ -86,6 +86,7 @@ require (
 	github.com/blang/semver v3.5.1+incompatible
 	github.com/docker/cli v24.0.2+incompatible
 	github.com/docker/go-connections v0.4.0
+	github.com/google/go-github v17.0.0+incompatible
 	github.com/google/go-github/v53 v53.2.0
 	github.com/juju/clock v1.0.3
 	github.com/juju/fslock v0.0.0-20160525022230-4d5c94c67b4b

go.sum

@@ -834,6 +834,7 @@ github.com/google/go-cmp v0.5.9/go.mod h1:17dUlkBOakJ0+DkrSSNjCkIjxS6bF9zb3elmeN
 github.com/google/go-containerregistry v0.5.1/go.mod h1:Ct15B4yir3PLOP5jsy0GNeYVaIZs/MK/Jz5any1wFW0=
 github.com/google/go-containerregistry v0.15.2 h1:MMkSh+tjSdnmJZO7ljvEqV1DjfekB6VUEAZgy3a+TQE=
 github.com/google/go-containerregistry v0.15.2/go.mod h1:wWK+LnOv4jXMM23IT/F1wdYftGWGr47Is8CG+pmHK1Q=
+github.com/google/go-github v17.0.0+incompatible h1:N0LgJ1j65A7kfXrZnUDaYCs/Sf4rEjNlfyDHW9dolSY=
 github.com/google/go-github v17.0.0+incompatible/go.mod h1:zLgOLi98H3fifZn+44m+umXrS52loVEgC2AApnigrVQ=
 github.com/google/go-github/v53 v53.2.0 h1:wvz3FyF53v4BK+AsnvCmeNhf8AkTaeh2SoYu/XUvTtI=
 github.com/google/go-github/v53 v53.2.0/go.mod h1:XhFRObz+m/l+UCm9b7KSIC3lT3NWSXGt7mOsAWEloao=

pkg/minikube/reason/reason.go

@@ -466,6 +466,8 @@ var (
 	KubernetesTooOld = Kind{ID: "K8S_OLD_UNSUPPORTED", ExitCode: ExControlPlaneUnsupported}
 	// a too new Kubernetes version was specified for minikube to use
 	KubernetesTooNew = Kind{ID: "K8S_NEW_UNSUPPORTED", ExitCode: ExControlPlaneUnsupported}
+	// error fetching github kubernetes version list
+	KubernetesNotConnect = Kind{ID: "K8S_FAIL_CONNECT"}
 	// minikube was unable to safely downgrade installed Kubernetes version
 	KubernetesDowngrade = Kind{
 		ID:       "K8S_DOWNGRADE_UNSUPPORTED",