class ActionMailbox::Ingresses::Mandrill::InboundEmailsController

def authenticated?
  if key.present?
    Authenticator.new(request, key).authenticated?
  else
    raise ArgumentError, <<~MESSAGE.squish
      Missing required Mandrill API key. Set action_mailbox.mandrill_api_key in your application's
      encrypted credentials or provide the MANDRILL_INGRESS_API_KEY environment variable.
    MESSAGE
  end
end