Update usage and long help for command.

cmd/provenanced/cmd/docgen.go

@@ -20,53 +20,68 @@ const (
 
 func GetDocGenCmd() *cobra.Command {
 	cmd := &cobra.Command{
-		Use:     "docgen",
-		Short:   "Generates cli documentation for the Provenance Blockchain.",
-		Long:    "",
+		Use:   "docgen <target directory> (--markdown) (--yaml) (--rest) (--manpages) [flags]",
+		Short: "Generates cli documentation for the Provenance Blockchain.",
+		Long: `Generates cli documentation for the Provenance Blockchain.
+Various documentation formats can be generated, including markdown, YAML, REST, and man pages. 
+To ensure the command's success, you must specify at least one format.
+A successful command will not only generate files in the selected formats but also create the target directory if it doesn't already exist.`,
 		Example: fmt.Sprintf("%s '/tmp' --yaml --markdown", docGenCmdStart),
 		Hidden:  true,
 		Args:    cobra.ExactArgs(1),
 		RunE: func(cmd *cobra.Command, args []string) error {
-			dir := args[0]
-			if !exists(dir) {
-				err := os.Mkdir(dir, 0755)
-				if err != nil {
-					return err
-				}
-			}
-
-			// Check if at least one flag is enabled
-
 			markdown, err := cmd.Flags().GetBool(FlagMarkdown)
 			if err != nil {
 				return err
 			}
-			if markdown {
-				doc.GenMarkdownTree(cmd.Root(), dir)
-			}
-
 			yaml, err := cmd.Flags().GetBool(FlagYaml)
 			if err != nil {
 				return err
 			}
-			if yaml {
-				doc.GenYamlTree(cmd.Root(), dir)
-			}
-
 			rest, err := cmd.Flags().GetBool(FlagRest)
 			if err != nil {
 				return err
 			}
-			if rest {
-				doc.GenReSTTree(cmd.Root(), dir)
-			}
-
 			manpage, err := cmd.Flags().GetBool(FlagManpage)
 			if err != nil {
 				return err
 			}
+
+			if !markdown && !yaml && !rest && !manpage {
+				return fmt.Errorf("at least one doc type must be specified.")
+			}
+
+			dir := args[0]
+			if !exists(dir) {
+				err := os.Mkdir(dir, 0755)
+				if err != nil {
+					return err
+				}
+			}
+
+			if markdown {
+				err = doc.GenMarkdownTree(cmd.Root(), dir)
+				if err != nil {
+					return err
+				}
+			}
+			if yaml {
+				err = doc.GenYamlTree(cmd.Root(), dir)
+				if err != nil {
+					return err
+				}
+			}
+			if rest {
+				err = doc.GenReSTTree(cmd.Root(), dir)
+				if err != nil {
+					return err
+				}
+			}
 			if manpage {
-				doc.GenManTree(cmd.Root(), nil, dir)
+				err = doc.GenManTree(cmd.Root(), nil, dir)
+				if err != nil {
+					return err
+				}
 			}
 
 			return nil