Add version command

cmd/cmd.go

@@ -6,6 +6,7 @@ import (
 	"os"
 	"time"
 
+	"gitea.e13.dev/e13/kubectl-unready/cmd/version"
 	"github.com/spf13/cobra"
 	corev1 "k8s.io/api/core/v1"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
@@ -35,6 +36,8 @@ func NewUnreadyCmd(ctx context.Context) *cobra.Command {
 
 	cmd.Flags().BoolVarP(&allNamespacesFlag, "all-namespaces", "A", false, "If present, list unready pods across all namespaces.")
 
+	cmd.AddCommand(version.NewVersionCmd(ctx))
+
 	return cmd
 }
 

cmd/version/version.go

@@ -0,0 +1,88 @@
+package version
+
+import (
+	"context"
+	"encoding/json/v2"
+	"fmt"
+	"os"
+	"runtime"
+	"runtime/debug"
+	"strconv"
+
+	"github.com/spf13/cobra"
+)
+
+func NewVersionCmd(ctx context.Context) *cobra.Command {
+	return &cobra.Command{
+		Use:   "version",
+		Short: "print the plugin's version",
+		RunE: func(cmd *cobra.Command, args []string) error {
+			if err := json.MarshalWrite(os.Stdout, Get()); err != nil {
+				return err
+			}
+			fmt.Println()
+			return nil
+		},
+	}
+}
+
+// GitTreeState represents the state of the Git repository's working tree
+// at the time of compilation. It provides a type-safe way to indicate whether
+// the source tree was clean, modified, or in an unknown state.
+type GitTreeState string
+
+func (g GitTreeState) String() string {
+	return string(g)
+}
+
+// These constants define all possible values for the GitTreeState contained in Info.
+const (
+	GitTreeStateModified GitTreeState = "modified"
+	GitTreeStateClean    GitTreeState = "clean"
+	GitTreeStateUnknown  GitTreeState = "unknown"
+)
+
+// Info carries the information gathered and returned by GetVersion().
+type Info struct {
+	Version       string
+	GitCommit     string
+	GitCommitTime string
+	GitTreeState  GitTreeState
+	GoVersion     string
+}
+
+// Get returns the version of the application derived directly from the runtime's debug information.
+func Get() Info {
+	var res Info
+	bi, ok := debug.ReadBuildInfo()
+	if !ok {
+		res.Version = "unknown"
+	}
+
+	res.Version = bi.Main.Version
+	for _, bs := range bi.Settings {
+		switch bs.Key {
+		case "vcs.revision":
+			res.GitCommit = bs.Value
+		case "vcs.modified":
+			mod, err := strconv.ParseBool(bs.Value)
+			if err != nil {
+				res.GitTreeState = GitTreeStateUnknown
+				continue
+			}
+			if mod {
+				res.GitTreeState = GitTreeStateModified
+				continue
+			}
+			res.GitTreeState = GitTreeStateClean
+		case "vcs.time":
+			res.GitCommitTime = bs.Value
+		default:
+			// we don't care about other settings for now
+		}
+	}
+
+	res.GoVersion = runtime.Version()
+
+	return res
+}