How to make Rails helper methods available when calling render_to_string to render a template

I have a ActiveMailer class, and inside I am sending emails with attached PDF template using the render_to_string method like this: ``` def send_sales_order(email_service) @email_service = email_service @sales_order = SalesOrder.find_by_cid(email_service.order[:id]) mail(:subject => I18n.t("custom_mailer.sales_order.subject", company_name: "test"), :to => @email_service.recipients) do |format| format.html format.pdf do attachments['purchase_order.pdf'] = WickedPdf.new.pdf_from_string( render_to_string('sales_orders/show.pdf.erb', locals: {current_company: @sales_order.company}) ) end end end ``` Inside the show.pdf.erb template, I called my helper methods defined elsewhere such as the current_company method defined in ApplicationController like follow: ``` class ApplicationController < ActionController::Base helper_method :current_company, :current_role def current_company return if current_user.nil? if session[:current_company_id].blank? session[:current_company_id] = current_user.companies.first.id.to_s end @current_company ||= Company.find(session[:current_company_id]) end ``` But these helper methods are not available when I use the render_to_string method to render the template, is there a way around this? Thanks