I created a website and I integrated payment using PayStack and it is fully functional, but something unusual came up sometime when a customer wanted to make a payment. After the successful payment processing, maybe something went wrong with the customer's Network provider but the customer was not redirected to a success page where to give values to database. So I implemented webhooks to get values from paystack and PUT THE CONTENTS in a .txt (webhookApi.txt) file but it seems something is wrong with the code and I can't figure it out.
`
<?php
// only a post with paystack signature header gets our attention
if ((strtoupper($_SERVER['REQUEST_METHOD']) != 'POST' ) || !array_key_exists('x-paystack-signature', $_SERVER) )
exit();
// Retrieve the request's body
$input = @file_get_contents("php://input");
define('PAYSTACK_SECRET_KEY','sk_live_xxxxxxxxxxxxxxxxxxxxxxxxxxx');
// validate event do all at once to avoid timing attack
if($_SERVER['HTTP_X_PAYSTACK_SIGNATURE'] !== hash_hmac('HMAC SHA512', $input, PAYSTACK_SECRET_KEY))
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);
$reference = $event->data->reference;
$email = $event->data->customer->email;
$eventMessage = $event->event;
file_put_contents("webhookApi.txt", PHP_EOL.$input, FILE_APPEND);
exit();
?>
`
