Check if vcluster chart version supports k8s version

config/default_extra_values.go

@@ -5,6 +5,8 @@ import (
 	"regexp"
 	"strconv"
 	"strings"
+
+	"github.com/blang/semver"
 )
 
 const (
@@ -71,6 +73,16 @@ var K8SEtcdVersionMap = map[string]string{
 	"1.27": "registry.k8s.io/etcd:3.5.7-0",
 }
 
+var vclusterVersionsWithK8sVersionSupport []semver.Version
+
+func init() {
+	vclusterVersionsWithK8sVersionSupport = []semver.Version{
+		semver.MustParse("0.20.0-beta.16"),
+		semver.MustParse("0.20.0-alpha.99"),
+		semver.MustParse("0.21.0-alpha.4"),
+	}
+}
+
 // ExtraValuesOptions holds the chart options
 type ExtraValuesOptions struct {
 	Distro string
@@ -91,21 +103,21 @@ type KubernetesVersion struct {
 	Minor string
 }
 
-func GetExtraValues(options *ExtraValuesOptions) (string, error) {
+func GetExtraValues(options *ExtraValuesOptions, chartVersion string) (string, error) {
 	fromConfig, err := NewDefaultConfig()
 	if err != nil {
 		return "", err
 	}
 
-	toConfig, err := getExtraValues(options)
+	toConfig, err := getExtraValues(options, chartVersion)
 	if err != nil {
 		return "", fmt.Errorf("get extra values: %w", err)
 	}
 
 	return Diff(fromConfig, toConfig)
 }
 
-func getExtraValues(options *ExtraValuesOptions) (*Config, error) {
+func getExtraValues(options *ExtraValuesOptions, chartVersion string) (*Config, error) {
 	vConfig, err := NewDefaultConfig()
 	if err != nil {
 		return nil, err
@@ -124,7 +136,7 @@ func getExtraValues(options *ExtraValuesOptions) (*Config, error) {
 	}
 
 	// apply k8s values
-	err = applyK8SExtraValues(vConfig, options)
+	err = applyK8SExtraValues(vConfig, options, chartVersion)
 	if err != nil {
 		return nil, err
 	}
@@ -166,7 +178,7 @@ func applyK0SExtraValues(vConfig *Config, options *ExtraValuesOptions) error {
 	return nil
 }
 
-func applyK8SExtraValues(vConfig *Config, options *ExtraValuesOptions) error {
+func applyK8SExtraValues(vConfig *Config, options *ExtraValuesOptions, chartVersion string) error {
 	// get api server image
 	apiImage, err := getImageByVersion(options.KubernetesVersion, K8SAPIVersionMap)
 	if err != nil {
@@ -180,16 +192,63 @@ func applyK8SExtraValues(vConfig *Config, options *ExtraValuesOptions) error {
 	}
 
 	// build values
-	if apiImage != "" {
-		vConfig.ControlPlane.Distro.K8S.Version = parseImage(apiImage).Tag
+	k8sVersion, err := getK8sVersion(chartVersion, apiImage)
+	if err != nil {
+		return err
 	}
+	vConfig.ControlPlane.Distro.K8S.Version = k8sVersion
+
 	if etcdImage != "" {
 		vConfig.ControlPlane.BackingStore.Etcd.Deploy.StatefulSet.Image = parseImage(etcdImage)
 	}
 
 	return nil
 }
 
+func getK8sVersion(chartVersion, apiImage string) (string, error) {
+	if apiImage == "" {
+		return "", nil
+	}
+	isSupported, err := isK8sVersionSupported(chartVersion)
+	if err != nil {
+		return "", err
+	}
+
+	if isSupported {
+		return parseImage(apiImage).Tag, nil
+	}
+	// if we set a non-empty value for a vcluster chart version that does not support
+	// the k8s version field, vcluster will panic
+	return "", nil
+}
+
+func isK8sVersionSupported(chartVersion string) (bool, error) {
+	if chartVersion == "" {
+		// probably dev chart
+		return true, nil
+	}
+	v, err := semver.Parse(strings.TrimPrefix(chartVersion, "v"))
+	if err != nil {
+		return false, err
+	}
+	for _, supportedStartVer := range vclusterVersionsWithK8sVersionSupport {
+		if v.Minor != supportedStartVer.Minor {
+			continue
+		}
+		if len(supportedStartVer.Pre) > 0 && len(v.Pre) > 0 && supportedStartVer.Pre[0] != v.Pre[0] {
+			// this is a special case- its possible in our releases for an alpha to be ahead of a beta;
+			// we cannot compare prebuilds unless they share the same first element.
+			return true, nil
+		}
+		if v.GTE(supportedStartVer) {
+			return true, nil
+		}
+		return false, nil
+	}
+	// in the case no relevant start version was found for minor we can assume k8s version is supported
+	return true, nil
+}
+
 func parseImage(image string) Image {
 	registry, repository, tag := SplitImage(image)
 	return Image{

pkg/cli/create_helm.go

@@ -265,7 +265,7 @@ func CreateHelm(ctx context.Context, options *CreateOptions, globalFlags *flags.
 	if err != nil {
 		return err
 	}
-	chartValues, err := config.GetExtraValues(chartOptions)
+	chartValues, err := config.GetExtraValues(chartOptions, options.ChartVersion)
 	if err != nil {
 		return err
 	}

pkg/cli/create_platform.go

@@ -612,7 +612,7 @@ func mergeValues(platformClient platform.Client, options *CreateOptions, log log
 	if err != nil {
 		return "", err
 	}
-	chartValues, err := vclusterconfig.GetExtraValues(chartOptions)
+	chartValues, err := vclusterconfig.GetExtraValues(chartOptions, options.ChartVersion)
 	if err != nil {
 		return "", err
 	}