Add version command

Author: leadpony

cmd/docksider/main.go

@@ -2,20 +2,24 @@ package main
 
 import (
 	"context"
+	_ "embed"
 	"log"
 	"os"
 	"os/signal"
 
 	"github.com/openclosed-dev/docksider/internal/cmd"
 )
 
+//go:embed version.txt
+var version string
+
 func main() {
 
 	log.SetFlags(0)
 
 	ctx, cancel := signal.NotifyContext(context.Background(), os.Interrupt)
 	defer cancel()
-	if err := cmd.NewRootCmd().ExecuteContext(ctx); err != nil {
+	if err := cmd.NewRootCmd(version).ExecuteContext(ctx); err != nil {
 		cancel()
 		os.Exit(1)
 	}

cmd/docksider/version.txt

@@ -0,0 +1 @@
+0.1.0

internal/cmd/root.go

@@ -1,20 +1,25 @@
 package cmd
 
 import (
+	"strings"
+
 	"github.com/openclosed-dev/docksider/internal/cmd/image"
 	"github.com/spf13/cobra"
 )
 
-func NewRootCmd() *cobra.Command {
+func NewRootCmd(version string) *cobra.Command {
 
 	const (
 		use   = "docksider [OPTIONS] COMMAND [ARG...]"
 		short = "A Docker-style CLI for pulling and pushing images directly to container registries"
 	)
 
+	version = strings.TrimSpace(version)
+
 	root := &cobra.Command{
 		Use:           use,
 		Short:         short,
+		Version:       version,
 		SilenceUsage:  true,
 		SilenceErrors: false,
 
@@ -33,6 +38,7 @@ func NewRootCmd() *cobra.Command {
 		image.NewImagesCmd(),
 		image.NewPullCmd(),
 		image.NewPushCmd(),
+		NewVersionCmd(version),
 	)
 
 	return root

internal/cmd/version.go

@@ -0,0 +1,27 @@
+package cmd
+
+import (
+	"fmt"
+
+	"github.com/spf13/cobra"
+)
+
+func NewVersionCmd(version string) *cobra.Command {
+
+	const (
+		use   = "version"
+		short = "Print the version"
+	)
+
+	cmd := &cobra.Command{
+		Use:   use,
+		Short: short,
+		RunE: func(cmd *cobra.Command, _ []string) error {
+			fmt.Fprintln(cmd.OutOrStdout(), version)
+			return nil
+		},
+		DisableFlagsInUseLine: true,
+	}
+
+	return cmd
+}