Debug SNS messages

sns.php

<?php

// Fetch the raw POST body containing the message
$postBody = file_get_contents('php://input');

error_log($postBody);

// JSON decode the body to an array of message data
$message = json_decode($postBody, true);
if ($message) {
    // Do something with the data
    error_log($message['Message']);
    error_log($message['SubscribeURL']);
}