--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"
+	"net/http"
+
+	"github.com/google/go-github/v53/github"
 	"golang.org/x/mod/semver"
 	"k8s.io/minikube/pkg/minikube/constants"
 )
@@ -34,3 +38,17 @@ func supportedKubernetesVersions() (releases []string) {
 	}
 	return releases
 }
+
+// IsInGitHubKubernetesVersions checks whether ver is in the GitHub list of K8s versions
+func IsInGitHubKubernetesVersions(ver string) (bool, error) {
+	ghc := github.NewClient(nil)
+
+	_, resp, err := ghc.Repositories.GetReleaseByTag(context.Background(), "kubernetes", "kubernetes", ver)
+	if err != nil {
+		if resp != nil && resp.StatusCode == http.StatusNotFound {
+			return false, nil
+		}
+		return false, err
+	}
+	return true, nil
+}

cmd/minikube/cmd/start.go

@@ -1771,6 +1771,22 @@ 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", out.V{"specified": nvs})
+			out.Styled(style.Verifying, "Searching the internet for Kubernetes version...")
+			found, err := cmdcfg.IsInGitHubKubernetesVersions(kubernetesVer)
+			if err != nil && !viper.GetBool(force) {
+				exit.Error(reason.KubernetesNotConnect, "error fetching Kubernetes version list from GitHub", err)
+			}
+			if found {
+				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 {{.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 +2023,14 @@ 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
+}

hack/update/go_github_version/update_go_github_version.go

@@ -67,6 +67,7 @@ func generateSchema() map[string]update.Item {
 		"hack/update/kubeadm_constants/update_kubeadm_constants.go",
 		"hack/update/kubernetes_versions_list/update_kubernetes_versions_list.go",
 		"pkg/perf/monitor/github.go",
+		"cmd/minikube/cmd/config/kubernetes_version.go",
 	}
 
 	schema := make(map[string]update.Item)

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",