How to get the logged-in user on the machine accessing the PHP page?

Question

I need to get the user who is logged in to the machine being used to access a certain PHP page. The PHP page is being served by an Apache. Through some researches, I found in the PHP documentation the following $_SERVER["REMOTE_USER"] and $_SERVER["PHP_AUTH_USER"] keys that at first would have the information I need, but these are not being returned by Apache. Is there any configuration in Apache or any way to have this information with PHP?

Answer 1

Depending on the environment Apache may be going through a proxy

You can do as suggested on: https://renaudmarti.net/posts/make-apache-proxy-remote-user-to-backend/

In your . htaccess add the following

RewriteEngine on
RewriteCond %{REMOTE_USER} (.*)
RewriteRule .* - [E=X_REMOTE_USER:%1]
RequestHeader set REMOTE_USER %{X_REMOTE_USER}e