feat: version command

main.go

@@ -15,11 +15,13 @@ func main() {
 	restartCmd := cmd.NewRestartCmd(cfg)
 	drainCmd := cmd.NewDrainCmd(cfg)
 	showCmd := cmd.NewShowCmd(cfg)
+	versionCmd := cmd.NewVersionCmd()
 
 	rootCmd.Subcommands = []*ffcli.Command{
 		restartCmd,
 		drainCmd,
 		showCmd,
+		versionCmd,
 	}
 
 	if err := rootCmd.Parse(os.Args[1:]); err != nil {

pkg/cmd/version.go

@@ -0,0 +1,23 @@
+package cmd
+
+import (
+	"context"
+	"fmt"
+
+	"github.com/peterbourgon/ff/v3/ffcli"
+)
+
+const Version = "v0.0.5"
+
+func NewVersionCmd() *ffcli.Command {
+	c := &ffcli.Command{
+		Name:       "version",
+		ShortUsage: "show version of kroller",
+		ShortHelp:  "show version of kroller",
+		Exec: func(context.Context, []string) error {
+			fmt.Printf("version: %s\n", Version)
+			return nil
+		},
+	}
+	return c
+}