View file Script/requests/listener.php

<?php
include("../includes/config.php");
session_start();
if($_POST['token_id'] != $_SESSION['token_id']) {
	return false;
}
include("../includes/classes.php");
include(getLanguage(null, (!empty($_GET['lang']) ? $_GET['lang'] : $_COOKIE['lang']), 2));
$db = new mysqli($CONF['host'], $CONF['user'], $CONF['pass'], $CONF['name']);
if ($db->connect_errno) {
    echo "Failed to connect to MySQL: (" . $db->connect_errno . ") " . $db->connect_error;
}
$db->set_charset("utf8");

$resultSettings = $db->query(getSettings());
$settings = $resultSettings->fetch_assoc();

// Turn on or off the debugging
$debug = 0; // 

// Define the sandbox
$sandbox = ($settings['paypalsand'] ? 1 : 0);

// IPN log file
$logfile = './ipn.log';

// PayPal request url
if($sandbox) {
	$paypalurl = "https://www.sandbox.paypal.com/cgi-bin/webscr";
} else {
	$paypalurl = "https://www.paypal.com/cgi-bin/webscr";
}

if($_POST) {
	$req = 'cmd='.urlencode('_notify-validate');

	foreach($_POST as $key => $value) {
		$value = urlencode(stripslashes($value));
		$req .= "&$key=$value";
	}

	$ch = curl_init();
	curl_setopt($ch, CURLOPT_URL, $paypalurl);
	curl_setopt($ch, CURLOPT_HTTP_VERSION, CURL_HTTP_VERSION_1_1);
	curl_setopt($ch, CURLOPT_HEADER, 0);
	curl_setopt($ch, CURLOPT_FORBID_REUSE, 1);
	curl_setopt($ch, CURLOPT_POST, 1);
	curl_setopt($ch, CURLOPT_RETURNTRANSFER,1);
	curl_setopt($ch, CURLOPT_POSTFIELDS, $req);
	if($debug) {
		curl_setopt($ch, CURLINFO_HEADER_OUT, 1);
		curl_setopt($ch, CURLOPT_SSL_VERIFYHOST, 0);
		curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, 0); 
	} else {
		curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, 1);
		curl_setopt($ch, CURLOPT_SSL_VERIFYHOST, 2);
	}
	curl_setopt($ch, CURLOPT_HTTPHEADER, array('Host: www'.$sandbox.'.sandbox.paypal.com'));
	$res = curl_exec($ch);
	
	// cURL error
	if(curl_errno($ch) != 0) {
		if($debug) {	
			error_log(date('[Y-m-d H:i e] '). "Can't connect to PayPal to validate IPN message: " . curl_error($ch) . PHP_EOL, 3, $logfile);
		}
		curl_close($ch);
	} else {
		// Log the entire HTTP response if debug is switched on.
		if($debug) {
			error_log(date('[Y-m-d H:i e] '). "HTTP request of validation request:". curl_getinfo($ch, CURLINFO_HEADER_OUT) ." for IPN payload: $req" . PHP_EOL, 3, $logfile);
			error_log(date('[Y-m-d H:i e] '). "HTTP response of validation request: $res" . PHP_EOL, 3, $logfile);

			// Split response headers and payload
			list($headers, $res) = explode("\r\n\r\n", $res, 2);
		}
		curl_close($ch);
	}
	
	if(strcmp($res, "VERIFIED") == 0) {
		$transaction_id = $_POST['txn_id'];
		$payerid = $_POST['payer_id'];
		$firstname = $_POST['first_name'];
		$lastname = $_POST['last_name'];
		$payeremail = $_POST['payer_email'];
		$paymentdate = $_POST['payment_date'];
		$paymentstatus = $_POST['payment_status'];
		$parent_txn_id = $_POST['parent_txn_id'];
		$mdate= date('Y-m-d h:i:s',strtotime($paymentdate));
		
		$managePayments = new managePayments();
		$managePayments->db = $db;
		$managePayments->url = $CONF['url'];
		$managePayments->per_page = $settings['rperpage'];
		
		// Payment Status Codes: https://developer.paypal.com/webapps/developer/docs/classic/ipn/integration-guide/IPNandPDTVariables/#id091EB04C0HS__id0913D0E0UQU
		// Set the new Payment Status whenever it changes
		if($paymentstatus == 'Canceled_Reversal') {
			$managePayments->updatePayment($parent_txn_id, 1);
		} elseif($paymentstatus == 'Reversed') {
			$managePayments->updatePayment($parent_txn_id, 2);
		} elseif($paymentstatus == 'Refunded') {
			$managePayments->updatePayment($parent_txn_id, 3);
		} elseif($paymentstatus == 'Pending') {
			$managePayments->updatePayment($parent_txn_id, 4);
		} elseif($paymentstatus == 'Failed') {
			$managePayments->updatePayment($parent_txn_id, 5);
		} elseif($paymentstatus == 'Denied') {
			$managePayments->updatePayment($parent_txn_id, 6);
		}
		
		if($debug) {
			$res = print_r($_POST, true);
			error_log(date('[Y-m-d H:i e] '). "Verified IPN: $res ". PHP_EOL, 3, $logfile);
		}
	} elseif(strcmp($res, "INVALID") == 0) {
		// log for manual investigation
		// Add business logic here which deals with invalid IPN messages
		if($debug) {
			error_log(date('[Y-m-d H:i e] '). "Invalid IPN: $req" . PHP_EOL, 3, $logfile);
		}
	}
}
mysqli_close($db);
?>