index.php

<?php

/* A modified version of the monitoring script described in the article at
  https://medium.com/winkhosting/server-monitoring-with-php-and-bash-scripts-c078616a6e2f

  For demonstration purposes only

  Since the monitor script does not send files, the script is written 
  to handle the POST request via routes
*/

// Received files storage path.
$_SAVEPATH = __DIR__ . "/files";

// Preparation of valid routes
$valid_route = array("storage", "memoryusage", "top10cpu", "uptime");

// Remove trailing slash from request URI
$route = ltrim($_SERVER["REQUEST_URI"], '/');

// Check valid routes and save POST content to the file to the $_SAVEPATH
if (in_array($route, $valid_route)) {
  $_SAVEPATH = $_SAVEPATH . "/" . date("Ymdhis") . "_" . $route . ".log";
  file_put_contents($_SAVEPATH, file_get_contents('php://input'));
  echo "File saved at {$_SAVEPATH}\n";
}