class DBi {
    public static $connection;
}
$dbhost = "192.168.31.30";
$dbuser = "test";
$dbpass = "test";
$dbname = "metal";
DBi::$connection = mysqli_connect($dbhost, $dbuser, $dbpass, $dbname);
if (mysqli_connect_errno()) {
  die ("Database connection failed: " . mysqli_connect_error() . " (" . mysqli_connect_errno() . ")");
}