code: def check_services(first_file)
        if first_file.start_with?('service:')
          service = first_file.sub(/service:/, '')
          SERVICES.each do |k,v|
            if k == service
              @files = v
            end
          end
        end
      end
docs: Check if the first file matches service:<service-name>
   and try to determine the files based on the service.
  
   first_file the first file given