name : observer_mail.php <?php require_once 'Log/observer.php'; class Log_observer_mail extends Log_observer { private $to = ''; private $subject = ''; private $pattern = ''; public function __construct($priority, $conf) { /* Call the base class constructor. */ parent::__construct($priority); /* Configure the observer. */ $this->to = $conf['to']; $this->subject = $conf['subject']; $this->pattern = $conf['pattern']; } public function notify($event): void { if (preg_match($this->pattern, $event['message']) != 0) { mail($this->to, $this->subject, $event['message']); } } } ?>