PHP Basic Authentication

php-auth.php

<?php

$auth_users = [
    'sysadmin' => 'kjhgkjhgkjhg'
];

if (!isset($_SERVER['PHP_AUTH_USER']) || !array_key_exists($_SERVER['PHP_AUTH_USER'], $auth_users)
|| !isset($_SERVER['PHP_AUTH_PW']) || ($_SERVER['PHP_AUTH_PW']) !== ($auth_users[$_SERVER['PHP_AUTH_USER']])) { 
    header('WWW-Authenticate: Basic realm="Admin"'); 
    header('HTTP/1.1 401 Access Denied'); 
    echo 'Unauthorized'; 
    exit; 
}

echo 'Welcome!!';