def set_index_options
        limit          = params[:limit].to_i > 0 ? params[:limit].to_i : nil
        reverse        = params[:reverse].present? ?
                           params[:reverse].to_s.to_boolean(false) : nil
        @index_options = params.permit(:filter, :filtered_by_key, :routing_scope, :devise_default_routes)
                               .to_h.symbolize_keys.merge(limit: limit, reverse: reverse)
      end
def set_index_options
        limit          = params[:limit].to_i > 0 ? params[:limit].to_i : nil
        reverse        = params[:reverse].present? ?
                           params[:reverse].to_s.to_boolean(false) : nil
        @index_options = params.permit(:filter, :filtered_by_key, :routing_scope, :devise_default_routes)
                               .to_h.symbolize_keys.merge(limit: limit, reverse: reverse)
      end
Sets options to load subscription index from request parameters.
 @api protected
 @return [Hash] options to load subscription index