Debugging ipn.php when using paypal sandbox ipn simulator

Question

How do I debug the ipn.php file when using the paypal sandbox ipn simulator tool?

The code looks like this:

// read the post from PayPal system and add 'cmd'  
$req = 'cmd=_notify-validate';

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

// post back to PayPal system to validate  
$header = "POST /cgi-bin/webscr HTTP/1.0\r\n";
$header. = "Content-Type: application/x-www-form-urlencoded\r\n";
$header. = "Content-Length: ".strlen($req)."\r\n\r\n";

$fp = fsockopen('ssl://www.sandbox.paypal.com', 443, $errno, $errstr, 30);

if (!$fp) {
    // HTTP ERROR  
} else {
    fputs($fp, $header.$req);

    while (!feof($fp)) {
        $res = fgets($fp, 1024);

        if (strcmp($res, "VERIFIED") == 0) {

            $DBH = new PDO("mysql:host=localhost;dbname=db", "user", "pass");
            $DBH - > setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);

            $STH = $DBH - > prepare("update table2 set status = :status where tracking_id = :tracking_id");

            $status = 1;
            parse_str($req, $data);

            $STH - > bindParam(':status', $status, PDO::PARAM_INT, 1);
            $STH - > bindParam(':tracking_id', 'id_goes_here', PDO::PARAM_STR, 50);

            $STH - > execute();

            $DBH = null;

        } else if (strcmp($res, "INVALID") == 0) {
            // do something else
        }
    }

    fclose($fp);
}

I normally use netbeans debug facility to debug, but how do I debug using the sandbox simulator? When I click send ipn from the sandbox ipn simulator, I get a message in the sandbox saying IPN successfully sent., but when I then go into my database to check the status, it's still 0.

Answer 1

Maybe problem is in parameter binding

$STH - > bindParam(':tracking_id', 'id_goes_here', PDO::PARAM_STR, 50);

if table 'table2' do not contain row with tracking_id = 'id_goes_here' update action will fail.

Try this

<?php

$testMode = false;
$url = 'https://www.paypal.com/cgi-bin/webscr';
if ($testMode === true)
    $url = 'https://www.sandbox.paypal.com/cgi-bin/webscr';

$ipnResponse = ''; // holds the IPN response from paypal
$ipnData = array(); // array will contain the POST values for IPN

$urlParsed = parse_url($url);

$req = 'cmd=_notify-validate'; // Add 'cmd' to req (ipn command)

// Read the post from PayPal system and add them to req
foreach ($_POST as $key => $value) {
    $ipnData["$key"] = $value;
    $value = urlencode(stripslashes($value));
    $req .= "&" . $key . "=" . $value;
}

// Open the connection to paypal
$fp = fsockopen($urlParsed['host'], "80", $errno, $errstr, 30);

// If could open the connection and check response
if ($fp) {

    fputs($fp, "POST " . $urlParsed['path'] . " HTTP/1.1\r\n");
    fputs($fp, "Host: " . $urlParsed['host'] . "\r\n");
    fputs($fp, "Content-type: application/x-www-form-urlencoded\r\n");
    fputs($fp, "Content-length: " . strlen($req) . "\r\n");
    fputs($fp, "Connection: close\r\n\r\n");
    fputs($fp, $req . "\r\n\r\n");

    // Loop through the response from the server and append to variable
    while (!feof($fp)) {
        $ipnResponse .= fgets($fp, 1024);
    }
    fclose($fp);

    // Valid IPN transaction.
    if (preg_match('/^VERIFIED/', $ipnResponse)) {
        // Some action on IPN validation - update payment status etc
        die("OK. IPN Validation: Success");     
    }
    // Invalid IPN transaction
    else {
        // Some action on IPN validation - update payment status etc
        die("ERROR. IPN Validation: Failed");
    }
}
// Else no connection, so maybe wrong url or other reasons, you can do another call later
else {
    die("ERROR. IPN Connection: fsockopen error");
}


?>