Use custom cli classes

cli_generate_secret.go

@@ -6,7 +6,12 @@ import (
 	"github.com/9seconds/mtg/v2/mtglib"
 )
 
-func runGenerateSecret(cli *CLI) {
+type cliCommandGenerateSecret struct {
+	HostName string `arg optional help:"Hostname to use for domain fronting. Default is '${domain_front}'." name:"hostname" default:"${domain_front}"` // nolint: lll, govet
+	Hex      bool   `help:"Print secret in hex encoding."`
+}
+
+func (c *cliCommandGenerateSecret) Run(cli *CLI) error { // nolint: unparam
 	secret := mtglib.GenerateSecret(cli.GenerateSecret.HostName)
 
 	if cli.GenerateSecret.Hex {
@@ -14,4 +19,6 @@ func runGenerateSecret(cli *CLI) {
 	} else {
 		fmt.Println(secret.Base64()) // nolint: forbidigo
 	}
+
+	return nil
 }