Paystack Webhook Code Skeleton, PHP

verify-and-handle-paystack-event.php

<?php
if ((strtoupper($_SERVER['REQUEST_METHOD']) != 'POST' ) || !array_key_exists('HTTP_X_PAYSTACK_SIGNATURE', $_SERVER) ) {
    // only a post with paystack signature header gets our attention
    exit();
}

// Retrieve the request's body
$input = @file_get_contents("php://input");
define('PAYSTACK_SECRET_KEY','sk_xxxx_xxxxxx');

if(!$_SERVER['HTTP_X_PAYSTACK_SIGNATURE'] || ($_SERVER['HTTP_X_PAYSTACK_SIGNATURE'] !== hash_hmac('sha512', $input, PAYSTACK_SECRET_KEY))){
  // silently forget this ever happened
  exit();
}


http_response_code(200);

// parse event (which is json string) as object
// Do something - that will not take long - with $event
$event = json_decode($input);
switch($event->event){
    // subscription.create
    case 'subscription.create':
        break;

    // charge.success
    case 'charge.success':
        break;

    // subscription.disable
    case 'subscription.disable':
        break;

    // invoice.create and invoice.update
    case 'invoice.create':
    case 'invoice.update':
        break;

}

exit();