First create an engine, for example with name 'cms'.
$ rails plugin new cms --mountable
This command will create full file tree for your engine.
Use manual and some extra tips from below - https://github.com/plataformatec/devise/wiki/How-To:-Use-devise-inside-a-mountable-engine.
Steps and tips:
| class ApplicationController < ActionController::Base | |
| before_filter :prepend_view_path_if_mobile | |
| def mobile_request? | |
| @mobile_request ||= (request.subdomains.first == domain_prefixes[:mobile]) | |
| end | |
| helper_method :mobile_request? | |
| def prepend_view_path_if_mobile | |
| prepend_view_path Rails.root + 'app' + 'views_mobile' if mobile_request? |
