public function send_message() {
        global $USER;

        $subjectraw = get_config('backup', 'backup_async_message_subject');
        $subjecttext = preg_replace_callback(
                '/\{([-_A-Za-z0-9]+)\}/u',
                array('async_helper', 'lookup_message_variables'),
                $subjectraw);

        $messageraw = get_config('backup', 'backup_async_message');
        $messagehtml = preg_replace_callback(
                '/\{([-_A-Za-z0-9]+)\}/u',
                array('async_helper', 'lookup_message_variables'),
                $messageraw);
        $messagetext = html_to_text($messagehtml);

        $message = new \core\message\message();
        $message->component = 'moodle';
        $message->name = 'asyncbackupnotification';
        $message->userfrom          = $USER;
        $message->userto            = $this->user;
        $message->subject           = $subjecttext;
        $message->fullmessage       = $messagetext;
        $message->fullmessageformat = FORMAT_HTML;
        $message->fullmessagehtml   = $messagehtml;
        $message->smallmessage      = '';
        $message->notification      = '1';

        $messageid = message_send($message);

        return $messageid;
    }