PHP Get Site URL Protocol - http vs https

I know it's late, although there is a much more convenient way to solve this kind of problem! The other solutions are quite messy; this is how I would do it:

$protocol = stripos($_SERVER['SERVER_PROTOCOL'],'https') === 0 ? 'https://' : 'http://';

...or even without condition if you prefer:

$protocol = strtolower(substr($_SERVER["SERVER_PROTOCOL"],0,strpos( $_SERVER["SERVER_PROTOCOL"],'/'))).'://';

Have a look at $_SERVER["SERVER_PROTOCOL"]

It is not automatic. Your top function looks ok.

This works for me

if (isset($_SERVER['HTTPS']) &&
    ($_SERVER['HTTPS'] == 'on' || $_SERVER['HTTPS'] == 1) ||
    isset($_SERVER['HTTP_X_FORWARDED_PROTO']) &&
    $_SERVER['HTTP_X_FORWARDED_PROTO'] == 'https') {
  $protocol = 'https://';
}
else {
  $protocol = 'http://';
}