Add version cmd

cmd/root.go

@@ -37,15 +37,17 @@ func Execute(version string) {
 		},
 	}
 
+	rootCmd.PersistentFlags().Bool("help", false, "Show help for command")
 	rootCmd.SetHelpFunc(root.HelpFunc)
 	rootCmd.SetHelpCommand(&cobra.Command{Hidden: true})
 
+	rootCmd.PersistentFlags().Bool("version", false, "Show ae version")
+	rootCmd.SetVersionTemplate(versionFormat(version))
+
+	rootCmd.AddCommand(newVersionCommand(version))
 	rootCmd.AddCommand(newCompletionCommand())
 	rootCmd.AddCommand(newUserCommands()...)
 
-	rootCmd.PersistentFlags().Bool("help", false, "Show help for command")
-	rootCmd.PersistentFlags().Bool("version", false, "Show ae version")
-
 	if err := rootCmd.Execute(); err != nil {
 		fmt.Println(err)
 		os.Exit(1)

cmd/version.go

@@ -0,0 +1,37 @@
+package cmd
+
+import (
+	"fmt"
+	"regexp"
+
+	"github.com/spf13/cobra"
+)
+
+func newVersionCommand(version string) *cobra.Command {
+	cmd := &cobra.Command{
+		Use:    "version",
+		Hidden: true,
+
+		RunE: func(cmd *cobra.Command, args []string) error {
+			fmt.Fprint(cmd.OutOrStdout(), versionFormat(version))
+			return nil
+		},
+	}
+
+	return cmd
+}
+
+func versionFormat(version string) string {
+	return fmt.Sprintf("ae version %s\n%s\n", version, changelogURL(version))
+}
+
+func changelogURL(version string) string {
+	path := "https://github.com/IQ2i/aergie"
+
+	r := regexp.MustCompile(`^\d+\.\d+\.\d+$`)
+	if !r.MatchString(version) {
+		return fmt.Sprintf("%s/releases/latest", path)
+	}
+
+	return fmt.Sprintf("https://github.com/IQ2i/aergie/releases/tag/v%s", version)
+}

cmd/version_test.go

@@ -0,0 +1,28 @@
+package cmd
+
+import (
+	"testing"
+)
+
+func TestFormat(t *testing.T) {
+	expects := "ae version 1.0.0\nhttps://github.com/IQ2i/aergie/releases/tag/v1.0.0\n"
+	if got := versionFormat("1.0.0"); got != expects {
+		t.Errorf("versionFormat() = %q, wants %q", got, expects)
+	}
+}
+
+func TestChangelogURL(t *testing.T) {
+	tag := "1.0.0"
+	url := "https://github.com/IQ2i/aergie/releases/tag/v1.0.0"
+	result := changelogURL(tag)
+	if result != url {
+		t.Errorf("expected %s to create url %s but got %s", tag, url, result)
+	}
+
+	tag = "DEV"
+	url = "https://github.com/IQ2i/aergie/releases/latest"
+	result = changelogURL(tag)
+	if result != url {
+		t.Errorf("expected %s to create url %s but got %s", tag, url, result)
+	}
+}