Implemented simple rendering of generic HTML as result of handler by adding support for creation of templates for every result of every handler. If we create proper file (compatible with GStringTemplateEngine) and we put it under correct name (ie. UsersListGet.html in same folder as UsersList.groovy file containing handler for action GET) and in Accept HTTP header we will suggest text/html as supported type then this renderer will be used to process results of handler before sending them to user. Every browser sends Accept HTTP header containing text/html part as most important accepted result of request so this rendering mechanism would be triggered by every request from browser if it is not changes or if request will not contain HTTP type parameter set to other value (ie. application/xml or @application/json@)

Example file template files are available in project directory next to groovy handlers.

I also introduced support for header and footer files which might be placed in top directory of rest scripts and might contain header and footer parts of page to incude by template files for particular handlers.