feat(cluster-version): add new command

cmd/cluster-version.go

@@ -0,0 +1,152 @@
+// SPDX-FileCopyrightText: 2024 SAP SE or an SAP affiliate company and Greenhouse contributors
+// SPDX-License-Identifier: Apache-2.0
+
+package cmd
+
+import (
+	"crypto/tls"
+	"crypto/x509"
+	"encoding/json"
+	"fmt"
+	"net/http"
+	"os"
+	"strings"
+
+	"github.com/spf13/cobra"
+	"k8s.io/apimachinery/pkg/version"
+	"k8s.io/client-go/kubernetes"
+	"k8s.io/client-go/rest"
+	clientcmd "k8s.io/client-go/tools/clientcmd"
+)
+
+var clusterVersionCmd = &cobra.Command{
+	Use:   "cluster-version",
+	Short: "Prints the cluster version of the context in kubeconfig",
+	RunE:  runClusterVersion,
+}
+
+var (
+	kubeconfig  string
+	kubecontext string
+)
+
+func runClusterVersion(cmd *cobra.Command, args []string) error {
+
+	cfg, err := clientcmd.BuildConfigFromFlags("", kubeconfig)
+	if err != nil {
+		return fmt.Errorf("failed to build kubeconfig: %w", err)
+	}
+
+	if kubecontext != "" {
+		cfg, err = configWithContext(kubecontext, kubeconfig)
+		if err != nil {
+			return fmt.Errorf("failed to build kubeconfig with context %s: %w", kubecontext, err)
+		}
+	}
+
+	// 1) Try unauthenticated GET /version
+	version, err := getUnauthenticatedVersion(cfg)
+	if err != nil {
+		// 2) Fallback to authenticated
+		if !hasAuth(cfg) {
+			return fmt.Errorf("no authentication methods found in your kubeconfig. please authenticate (`kubelogin`, etc.) and try again.")
+		}
+
+		clientset, cerr := kubernetes.NewForConfig(cfg)
+		if cerr != nil {
+			return fmt.Errorf("failed to create client: %w", cerr)
+		}
+		version, err = clientset.Discovery().ServerVersion()
+		if err != nil {
+			return fmt.Errorf("authenticated version fetch failed: %w", err)
+		}
+	}
+
+	// print out the relevant fields
+	parts := strings.Split(version.GitVersion, "-")
+	clean := parts[0]
+	parts = strings.Split(clean, "+")
+	clean = parts[0]
+	clusterVersion := strings.TrimPrefix(clean, "v")
+	fmt.Println(clusterVersion)
+	return nil
+}
+
+// hasAuth returns true if the rest.Config contains any credential source.
+func hasAuth(cfg *rest.Config) bool {
+	if cfg.BearerToken != "" || cfg.BearerTokenFile != "" {
+		return true
+	}
+	if cfg.Username != "" && cfg.Password != "" {
+		return true
+	}
+	if len(cfg.TLSClientConfig.CertData) > 0 || cfg.TLSClientConfig.CertFile != "" {
+		return true
+	}
+	if cfg.ExecProvider != nil {
+		return true
+	}
+
+	if cfg.ExecProvider != nil {
+		return true
+	}
+	if cfg.AuthProvider != nil {
+		if cfg.AuthProvider.Config["id-token"] != "" {
+			return true
+		}
+	}
+	return false
+}
+
+// getUnauthenticatedVersion does a direct HTTP GET to /version,
+// using the same Host and CA / TLS settings from cfg, but no creds.
+func getUnauthenticatedVersion(cfg *rest.Config) (*version.Info, error) {
+	url := strings.TrimRight(cfg.Host, "/") + "/version"
+
+	// build TLS config
+	tlsCfg := &tls.Config{}
+	if cfg.TLSClientConfig.Insecure {
+		tlsCfg.InsecureSkipVerify = true
+	}
+
+	// trust the same CA if provided
+	if len(cfg.TLSClientConfig.CAData) > 0 {
+		pool := x509.NewCertPool()
+		if ok := pool.AppendCertsFromPEM(cfg.TLSClientConfig.CAData); !ok {
+			return nil, fmt.Errorf("failed to append CA data")
+		}
+		tlsCfg.RootCAs = pool
+	} else if cfg.TLSClientConfig.CAFile != "" {
+		pem, err := os.ReadFile(cfg.TLSClientConfig.CAFile)
+		if err != nil {
+			return nil, err
+		}
+		pool := x509.NewCertPool()
+		if ok := pool.AppendCertsFromPEM(pem); !ok {
+			return nil, fmt.Errorf("failed to append CA file")
+		}
+		tlsCfg.RootCAs = pool
+	}
+
+	client := &http.Client{Transport: &http.Transport{TLSClientConfig: tlsCfg}}
+	resp, err := client.Get(url)
+	if err != nil {
+		return nil, err
+	}
+	defer resp.Body.Close()
+
+	if resp.StatusCode != http.StatusOK {
+		return nil, fmt.Errorf("unexpected HTTP status: %s", resp.Status)
+	}
+
+	var v version.Info
+	if err := json.NewDecoder(resp.Body).Decode(&v); err != nil {
+		return nil, err
+	}
+	return &v, nil
+}
+
+func init() {
+	clusterVersionCmd.Flags().StringVarP(&kubeconfig, "kubeconfig", "k", clientcmd.RecommendedHomeFile, "kubeconfig file path")
+	clusterVersionCmd.Flags().StringVarP(&kubecontext, "context", "c", "", "cluster version of the specified context in kubeconfig")
+}

cmd/root.go

@@ -22,4 +22,5 @@ func Execute() error {
 func init() {
 	// Add subcommands here
 	rootCmd.AddCommand(syncCmd)
+	rootCmd.AddCommand(clusterVersionCmd)
 }

go.mod

@@ -1,64 +1,67 @@
 module github.com/cloudoperators/cloudctl
 
-go 1.23.4
+go 1.24.0
+
+toolchain go1.24.2
 
 require (
-	github.com/cloudoperators/greenhouse v0.0.1-alpha.1
+	github.com/cloudoperators/greenhouse v0.3.0-rc.1
 	github.com/spf13/cobra v1.9.1
 	github.com/spf13/viper v1.20.1
-	k8s.io/apimachinery v0.32.4
-	k8s.io/client-go v0.32.4
+	k8s.io/apimachinery v0.33.0
+	k8s.io/client-go v0.33.0
 	sigs.k8s.io/controller-runtime v0.20.4
 )
 
 require (
 	github.com/davecgh/go-spew v1.1.2-0.20180830191138-d8f796af33cc // indirect
-	github.com/emicklei/go-restful/v3 v3.11.2 // indirect
+	github.com/emicklei/go-restful/v3 v3.12.2 // indirect
 	github.com/evanphx/json-patch/v5 v5.9.11 // indirect
-	github.com/fsnotify/fsnotify v1.8.0 // indirect
-	github.com/fxamacker/cbor/v2 v2.7.0 // indirect
+	github.com/fsnotify/fsnotify v1.9.0 // indirect
+	github.com/fxamacker/cbor/v2 v2.8.0 // indirect
 	github.com/go-logr/logr v1.4.2 // indirect
-	github.com/go-openapi/jsonpointer v0.21.0 // indirect
-	github.com/go-openapi/jsonreference v0.20.4 // indirect
-	github.com/go-openapi/swag v0.23.0 // indirect
+	github.com/go-openapi/jsonpointer v0.21.1 // indirect
+	github.com/go-openapi/jsonreference v0.21.0 // indirect
+	github.com/go-openapi/swag v0.23.1 // indirect
 	github.com/go-viper/mapstructure/v2 v2.2.1 // indirect
 	github.com/gogo/protobuf v1.3.2 // indirect
-	github.com/golang/protobuf v1.5.4 // indirect
-	github.com/google/gnostic-models v0.6.9-0.20230804172637-c7be7c783f49 // indirect
-	github.com/google/go-cmp v0.6.0 // indirect
-	github.com/google/gofuzz v1.2.0 // indirect
+	github.com/google/gnostic-models v0.6.9 // indirect
+	github.com/google/go-cmp v0.7.0 // indirect
 	github.com/google/uuid v1.6.0 // indirect
 	github.com/inconshreveable/mousetrap v1.1.0 // indirect
 	github.com/josharian/intern v1.0.0 // indirect
 	github.com/json-iterator/go v1.1.12 // indirect
-	github.com/mailru/easyjson v0.7.7 // indirect
+	github.com/mailru/easyjson v0.9.0 // indirect
 	github.com/modern-go/concurrent v0.0.0-20180306012644-bacd9c7ef1dd // indirect
 	github.com/modern-go/reflect2 v1.0.2 // indirect
 	github.com/munnerz/goautoneg v0.0.0-20191010083416-a7dc8b61c822 // indirect
-	github.com/pelletier/go-toml/v2 v2.2.3 // indirect
-	github.com/sagikazarmark/locafero v0.7.0 // indirect
+	github.com/pelletier/go-toml/v2 v2.2.4 // indirect
+	github.com/pkg/errors v0.9.1 // indirect
+	github.com/sagikazarmark/locafero v0.9.0 // indirect
 	github.com/sourcegraph/conc v0.3.0 // indirect
-	github.com/spf13/afero v1.12.0 // indirect
-	github.com/spf13/cast v1.7.1 // indirect
+	github.com/spf13/afero v1.14.0 // indirect
+	github.com/spf13/cast v1.8.0 // indirect
 	github.com/spf13/pflag v1.0.6 // indirect
 	github.com/subosito/gotenv v1.6.0 // indirect
 	github.com/x448/float16 v0.8.4 // indirect
 	go.uber.org/multierr v1.11.0 // indirect
-	golang.org/x/net v0.38.0 // indirect
-	golang.org/x/oauth2 v0.25.0 // indirect
-	golang.org/x/sys v0.31.0 // indirect
-	golang.org/x/term v0.30.0 // indirect
-	golang.org/x/text v0.23.0 // indirect
-	golang.org/x/time v0.8.0 // indirect
-	google.golang.org/protobuf v1.36.1 // indirect
+	golang.org/x/net v0.40.0 // indirect
+	golang.org/x/oauth2 v0.30.0 // indirect
+	golang.org/x/sys v0.33.0 // indirect
+	golang.org/x/term v0.32.0 // indirect
+	golang.org/x/text v0.25.0 // indirect
+	golang.org/x/time v0.11.0 // indirect
+	google.golang.org/protobuf v1.36.6 // indirect
+	gopkg.in/evanphx/json-patch.v4 v4.12.0 // indirect
 	gopkg.in/inf.v0 v0.9.1 // indirect
 	gopkg.in/yaml.v3 v3.0.1 // indirect
-	k8s.io/api v0.32.4 // indirect
-	k8s.io/apiextensions-apiserver v0.32.1 // indirect
+	k8s.io/api v0.33.0 // indirect
+	k8s.io/apiextensions-apiserver v0.33.0 // indirect
 	k8s.io/klog/v2 v2.130.1 // indirect
-	k8s.io/kube-openapi v0.0.0-20241105132330-32ad38e42d3f // indirect
-	k8s.io/utils v0.0.0-20241104100929-3ea5e8cea738 // indirect
-	sigs.k8s.io/json v0.0.0-20241010143419-9aa6b5e7a4b3 // indirect
-	sigs.k8s.io/structured-merge-diff/v4 v4.4.2 // indirect
+	k8s.io/kube-openapi v0.0.0-20250318190949-c8a335a9a2ff // indirect
+	k8s.io/utils v0.0.0-20250502105355-0f33e8f1c979 // indirect
+	sigs.k8s.io/json v0.0.0-20241014173422-cfa47c3a1cc8 // indirect
+	sigs.k8s.io/randfill v1.0.0 // indirect
+	sigs.k8s.io/structured-merge-diff/v4 v4.7.0 // indirect
 	sigs.k8s.io/yaml v1.4.0 // indirect
 )