feat: Add new version subcommand (#10)

cmd/graphql-schema-picker/main.go

@@ -4,6 +4,16 @@ import (
 	"github.com/kevinmichaelchen/graphql-schema-picker/internal/cli"
 )
 
+var (
+	version = "dev"
+	commit  = "none"
+	date    = "unknown"
+)
+
 func main() {
-	cli.Main()
+	cli.Main(cli.LDFlags{
+		Version: version,
+		Commit:  commit,
+		Date:    date,
+	})
 }

internal/cli/cli.go

@@ -20,15 +20,25 @@ var rootCmd = &cobra.Command{
 }
 
 var (
+	ldFlags            LDFlags
 	sdlFile            string
 	debug              bool
 	dryRun             bool
 	desiredDefinitions []string
 	output             string
 )
 
+// LDFlags contain fields that get linked and compiled into the final binary
+// program at build time.
+type LDFlags struct {
+	Version string
+	Commit  string
+	Date    string
+}
+
 func init() {
 	rootCmd.AddCommand(pick)
+	rootCmd.AddCommand(versionCmd)
 
 	rootCmd.PersistentFlags().StringVarP(&sdlFile, "sdl-file", "f", "", "path to an SDL file")
 	rootCmd.PersistentFlags().BoolVarP(&debug, "debug", "", false, "verbose debug logging")
@@ -38,7 +48,8 @@ func init() {
 	pick.Flags().StringVarP(&output, "output", "o", "", "where the resulting schema/SDL file is written")
 }
 
-func Main() {
+func Main(ldf LDFlags) {
+	ldFlags = ldf
 	if err := rootCmd.Execute(); err != nil {
 		log.Error("execution failed", "err", err)
 		os.Exit(1)

internal/cli/cli_version.go

@@ -0,0 +1,17 @@
+package cli
+
+import (
+	"fmt"
+	"github.com/spf13/cobra"
+)
+
+var versionCmd = &cobra.Command{
+	Use:   "version",
+	Short: "Prints CLI version info",
+	Long:  `Prints CLI version info`,
+	Run:   fnVersion,
+}
+
+func fnVersion(cmd *cobra.Command, args []string) {
+	fmt.Printf("version %s\n", ldFlags.Version)
+}