Will man in einer Liveumgebung schell mal was testen, sollte man wenigstens einen IP-Filter einbauen:

function getRemoteAddress() {
    if ( ! empty( $_SERVER['HTTP_CLIENT_IP'] ) ) {
      $remoteAddress = $_SERVER['HTTP_CLIENT_IP']; // ip from share internet
    } elseif ( ! empty( $_SERVER['HTTP_X_FORWARDED_FOR'] ) ) {
     $remoteAddress = $_SERVER['HTTP_X_FORWARDED_FOR']; // ip from proxy
    } elseif ( ! empty( $_SERVER['REMOTE_ADDR'] ) ) {
     $remoteAddress = $_SERVER['REMOTE_ADDR'];
    } else {
     $remoteAddress = '';
    }
  return $remoteAddress;
}

$remoteAddress = getRemoteAddress();

if($remoteAddress == '80.81.23.234'){
  // doSomething
}
// oder mit zwei IP's
if($remoteAddress == '80.81.23.234' || $remoteAddress == '88.116.109.126'){
  // doSomething
}

/* ALT
if($_SERVER['REMOTE_ADDR'] == '80.81.23.234'){
  // doSomething
}
// oder mit zwei IP's
if($_SERVER['REMOTE_ADDR'] == '80.81.23.234' || $_SERVER[ 'REMOTE_ADDR'] == '88.116.109.126'){
  // doSomething
}
*/