ITSynOpen/server/ping.php

<?php
require_once('config.inc.php');

$apikeys = $config['ping'];

header('Content-type: text/plain');
if ($_SERVER['REQUEST_METHOD'] == 'POST' &&
    isset($_GET['apikey']) && in_array($_GET['apikey'], $apikeys, true))
{
    file_put_contents ( 'pinged.txt' , 'true' );
    echo $str;
} else {
    $str=file_get_contents('pinged.txt');
    echo "API Key Missing (must be POST method)!\n";
    echo $str;
}
?>