public function addAttachmentFromFile($name, $path, $mimeType = 'application/octet-stream', $contentId = null)
    {
        if (file_exists($path) && is_file($path) && is_readable($path)) {
            $this->addAttachmentFromData($name, file_get_contents($path), $mimeType, $contentId);
        }
    }