Header for method devise invitable

header_for.rb

User.invite!({:email => "[email protected]", :name => "name one"}, User.first)

  def headers_for(action)
    headers = {}
    case action
    when :invitation_instructions
      headers.merge!({
        :subject => self.invited_by ? self.invited_by.name.titleize + " invited you to MyApp" : "Invitation",
        :reply_to => self.invited_by ? self.invited_by.to_e : "",
        :from => self.invited_by ? "#{self.invited_by.name.gsub(/\W/, ' ').titleize} via MyApp <[email protected]>" : "MyApp <[email protected]>"
      })
    end
    headers
  end