public function getMimeType($filename)
	{
		if ( ! file_exists($filename)) {
			throw new Exception\RuntimeException('File does not exist');
		}
		$finfo = finfo_open(FILEINFO_MIME_TYPE);
		$mimeType = finfo_file($finfo, $filename);
		finfo_close($finfo);
		return $mimeType;
	}