Change a php command in a script

Maybe i didn’t understand your problem either. Can’t you just create new keys with the PHP script you mentioned?

If you only have a a web service not not a php command line:

I think the first problem is the fact that you can not use shell_exec() in your php script. So i searched the internet for a php version. Please first check this script. Does it work?

<?php
$password = trim(substr(base64_encode(mt_rand()), 0, 47));
$hash = password_hash($password, PASSWORD_DEFAULT);
echo "hash: " . $hash . "<br>";
echo "password: " . $password . "<br>";
?>

If yes i can post you the part for writing to a file.
hash for updater.secret and password is cleartext password.