使用file_put_contents将当前的php页面保存为服务器的html

I have this code for save current page output to directory on my server it's working good now but i want to add security password to that page. What is the ways for secure that saved page ?

date_default_timezone_set('Europe/Istanbul');
$path = "backup/";
$date = date('d', time());
$number= $date;
$name = $number;
$filetype = ".html";
file_put_contents(html_entity_decode($path.$name.$filetype), ob_get_contents());

Thank you.