PayPal IPN Sent with 200 response but my database is not updating - php

Question

I am trying to implement the PayPal IPN solution. I am checking the IPN History page of my saccount and all messages are being sent with a 200 response. The problem is that nothing in my DB is being updated or inserted.
My environment is:
PHP 7.4
Apache
CentOS 8
I also tried to log something to a file but I am failing to do so. This is the first time I try to implement the PayPal IPN and I am very confused.
This is my current code:
<?php
class PaypalIPN
{
/** #var bool Indicates if the sandbox endpoint is used. */
private $use_sandbox = false;
/** #var bool Indicates if the local certificates are used. */
private $use_local_certs = true;
/** Production Postback URL */
const VERIFY_URI = 'https://ipnpb.paypal.com/cgi-bin/webscr';
/** Sandbox Postback URL */
const SANDBOX_VERIFY_URI = 'https://ipnpb.sandbox.paypal.com/cgi-bin/webscr';
/** Response from PayPal indicating validation was successful */
const VALID = 'VERIFIED';
/** Response from PayPal indicating validation failed */
const INVALID = 'INVALID';
const DEBUG = true;
/**
* Sets the IPN verification to sandbox mode (for use when testing,
* should not be enabled in production).
* #return void
*/
public function useSandbox()
{
$this->use_sandbox = true;
}
/**
* Sets curl to use php curl's built in certs (may be required in some
* environments).
* #return void
*/
public function usePHPCerts()
{
$this->use_local_certs = false;
}
/**
* Determine endpoint to post the verification data to.
*
* #return string
*/
public function getPaypalUri()
{
if ($this->use_sandbox) {
return self::SANDBOX_VERIFY_URI;
} else {
return self::VERIFY_URI;
}
}
/**
* Verification Function
* Sends the incoming post data back to PayPal using the cURL library.
*
* #return bool
* #throws Exception
*/
public function verifyIPN()
{
if ( ! count($_POST)) {
throw new Exception("Missing POST Data");
}
$raw_post_data = file_get_contents('php://input');
$raw_post_array = explode('&', $raw_post_data);
$myPost = array();
foreach ($raw_post_array as $keyval) {
$keyval = explode('=', $keyval);
if (count($keyval) == 2) {
// Since we do not want the plus in the datetime string to be encoded to a space, we manually encode it.
if ($keyval[0] === 'payment_date') {
if (substr_count($keyval[1], '+') === 1) {
$keyval[1] = str_replace('+', '%2B', $keyval[1]);
}
}
$myPost[$keyval[0]] = urldecode($keyval[1]);
}
}
// Build the body of the verification post request, adding the _notify-validate command.
$req = 'cmd=_notify-validate';
foreach ($myPost as $key => $value) {
$value = urlencode($value);
$req .= "&$key=$value";
}
// Post the data back to PayPal, using curl. Throw exceptions if errors occur.
$ch = curl_init($this->getPaypalUri());
curl_setopt($ch, CURLOPT_HTTP_VERSION, CURL_HTTP_VERSION_1_1);
curl_setopt($ch, CURLOPT_POST, 1);
curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);
curl_setopt($ch, CURLOPT_POSTFIELDS, $req);
curl_setopt($ch, CURLOPT_SSLVERSION, 6);
curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, 1);
curl_setopt($ch, CURLOPT_SSL_VERIFYHOST, 2);
// This is often required if the server is missing a global cert bundle, or is using an outdated one.
if ($this->use_local_certs) {
curl_setopt($ch, CURLOPT_CAINFO, __DIR__ . "/cert/cacert.pem");
}
curl_setopt($ch, CURLOPT_FORBID_REUSE, 1);
curl_setopt($ch, CURLOPT_CONNECTTIMEOUT, 30);
curl_setopt($ch, CURLOPT_HTTPHEADER, array(
'User-Agent: PHP-IPN-Verification-Script',
'Connection: Close',
));
$res = curl_exec($ch);
if ( ! ($res)) {
$errno = curl_errno($ch);
$errstr = curl_error($ch);
curl_close($ch);
throw new Exception("cURL error: [$errno] $errstr");
}
$info = curl_getinfo($ch);
$http_code = $info['http_code'];
if ($http_code != 200) {
throw new Exception("PayPal responded with http code $http_code");
}
curl_close($ch);
// Check if PayPal verifies the IPN data, and if so, return true.
if ($res == self::VALID) {
// crea el LOG
if($this->DEBUG == true) {
error_log(date('[Y-m-d H:i e] '). "IPN Verification: $req ". PHP_EOL, 3, 'ipn.log');
}
return true;
} else {
// crea el LOG
if($this->DEBUG == true) {
error_log(date('[Y-m-d H:i e] '). "IPN Verification: $req ". PHP_EOL, 3, 'ipn.log');
}
return false;
}
}
}
$ipn = new PaypalIPN();
// Use the sandbox endpoint during testing.
$ipn->useSandbox();
$verified = $ipn->verifyIPN();
if ($verified) {
/*
* Process IPN
* A list of variables is available here:
* https://developer.paypal.com/webapps/developer/docs/classic/ipn/integration-guide/IPNandPDTVariables/
*/
$payment_amount = $_POST['mc_gross'];
$payment_status = $_POST['payment_status'];
$custom = $_POST['custom'];
$payer_email = $_POST['payer_email'];
$txn_id = $_POST['txn_id'];
$receiver_email = $_POST['receiver_email'];
$item_name = $_POST['item_name'];
$payment_currency = $_POST['mc_currency'];
$item_number = $_POST['item_number'];
if($payment_amount >= '20') {
// Donation is $20 or higher, so let's add 20% to the coins.
$coins = $payment_amount*10*1.2;
}
else {
// Donation is less than $20, no bonus.
$coins = $payment_amount*10;
}
// Add E. Coins
$acc = new PDO("sqlsrv:Server=myhost;Database=mydb", "myusr", "mypass");
$add = $acc->prepare("UPDATE CashAccount SET Cash = Cash + :coins WHERE ID = :account");
$add->bindParam(':coins', $coins, PDO::PARAM_INT);
$add->bindParam(':account', $custom, PDO::PARAM_STR);
$add->execute();
// Log the donation
$db = new PDO("sqlsrv:Server=myhost;Database=mydb", "myusr", "mypass");
$method = 'PayPal';
$query = $db->prepare("INSERT INTO logs (Account, Amount, Coins, Method, Date, Email) VALUES (:account, :amount, :coins, :method, GETDATE(), :email)");
$query->bindParam(':account', $custom, PDO::PARAM_STR);
$query->bindParam(':amount', $payment_amount, PDO::PARAM_INT);
$query->bindParam(':coins', $coins, PDO::PARAM_INT);
$query->bindParam(':method', $method, PDO::PARAM_STR);
$query->bindParam(':email', $payer_email, PDO::PARAM_STR);
$query->execute();
}
// Reply with an empty 200 response to indicate to paypal the IPN was received correctly.
header("HTTP/1.1 200 OK");
I also enbled IPN Notifications in my Business/Sandbox accounts and updated the URL to http://example.com/paypal_ipn.php
Here is my IPN History from the PayPal sandbox.
Maybe someone here can point me to the right direction.

Answer 1

Where have you looked for your ipn.log file?
PHP may not have write permissions to the current directory.
What happens if you turn on errors/warnings and access your IPN listener from a browser? Does it print errors to the screen, about not being able to open ipn.log for writing?
You may need to use an absolute path to a directory PHP does have permissions to write to, for example:
error_log("This is a message!", 3, "/tmp/ipn.log");