csrf_helper.rb

    def csrf_meta_tags
      if protect_against_forgery?
        [].tap do |tags|
          tags << tag('meta', {:name => 'csrf-param', :content => request_forgery_protection_token})
          tags << tag('meta', {:name => 'csrf-token', :content => form_authenticity_token})
        end.join("\n").html_safe
      end
    end