add custom help command

cli/cli.go

@@ -82,6 +82,7 @@ Version:
 	rootCmd.PersistentFlags().Bool("no-audit", try.Try(try.EnvBool("RELAY_NO_AUDIT"), try.Static(false)), "disable audit logs [$RELAY_NO_AUDIT=1]")
 	rootCmd.PersistentFlags().BoolVar(&cfg.Logger.DisableColor, "no-color", false, "disable colors in command output [$NO_COLOR=1]")
 
+	rootCmd.SetHelpCommand(cmd.HelpCmd())
 	rootCmd.AddCommand(cmd.AddCmd(manager))
 	rootCmd.AddCommand(cmd.DelCmd(manager))
 	rootCmd.AddCommand(cmd.LsCmd(manager))

internal/cmd/help.go

@@ -0,0 +1,32 @@
+package cmd
+
+import (
+	"fmt"
+
+	"github.com/spf13/cobra"
+)
+
+func HelpCmd() *cobra.Command {
+	cmd := &cobra.Command{
+		Use:          "help [command]",
+		Short:        "help for a command",
+		SilenceUsage: true,
+		RunE: func(c *cobra.Command, args []string) error {
+			cmd, _, e := c.Root().Find(args)
+
+			if cmd == nil || e != nil {
+				fmt.Printf("warning: unknown help topic %#q\n", args)
+
+				return e
+			}
+
+			if err := cmd.Help(); err != nil {
+				return err
+			}
+
+			return nil
+		},
+	}
+
+	return cmd
+}