The Script

The script below when placed at the head of or in place of the script you want to capture requests to will write all data sent to files in a directory of your choosing for later analaysis:

$dir = "/tmp/analysis/a-descriptive-directory-name/".date("Y/m/d/Hi.s");
mkdir($dir, 0700, true);

file_put_contents($dir."/_REQUEST", var_export($_REQUEST,true));
file_put_contents($dir."/_COOKIE", var_export($_COOKIE,true));
file_put_contents($dir."/_SERVER", var_export($_SERVER,true));
file_put_contents($dir."/_POST", var_export($_POST,true));
file_put_contents($dir."/_GET", var_export($_GET,true));
file_put_contents($dir."/_FILES", var_export($_FILES,true));

$data = file_get_contents('php://input');

file_put_contents($dir."/input", var_export($data,true));

Nothing complicated but hopefully it will save someone some time. I also made it avaliable as a Gist