Mike Griffiths

I’ve been using PayPal for web site payments for years now. I love the way you can just sign up for an account and begin taking payments quickly, unlike a lot of gateways where you need merchant accounts with banks and written permission and what not. I always recommend PayPal to my clients as it means minimal fuss and get’s their site online far faster.

One thing I’ve noticed though, is that there is no decent example code out their for their IPN (Instant Payment Notification) service, which informs your web application when a payment is made, so you can do whatever you need to do when the user pays; ship the product, send an email, send a download link, set their account to upgraded, whatever. So, quite simply, here’s mine…

It’s based on PayPal’s very old and out-dated example script. I’ve adapted it to work on today’s properly set up production servers and removed the causes of the massive amounts of Notices and Warnings PHP would spit out with the old code. It’s pretty simple to use, just edit the config vars at the top to suit yourself. It’s defaulted to the live set up. You can put your custom code to be executed when a successful payment is made around halfway down, just read the comments.

/*
 * @author Mike Griffiths
 * @website Mike-Griffiths.co.uk
 *
 * Use as you like but I'd appreciate a link back to my site and some credit.
 * Enjoy.
 *
 * Post comments on the blog post you found this code on (mike-griffiths.co.uk)
 * if you get stuck.
 *
 */

#############
# CONFIG
#############
$CONFIG = array();
/*
 * General
 */
$CONFIG['notify_email'] = "email@example.com"; // For debug info 

/*
 * Database
 */
$CONFIG['db_host'] = "localhost"; // Server, eg. 'localhost'
$CONFIG['db_user'] = "example";  // Username, eg. 'mike'
$CONFIG['db_pass'] = "example";  // Password, eg. '12345'
$CONFIG['db_name'] = "example";    // Database name 

############
# Script
############
// 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"; 

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

// assign posted variables to local variables
$item_name              = (empty($_POST['item_name']) ? '' : $_POST['item_name']);
$business               = (empty($_POST['business']) ? '' : $_POST['business']);
$item_number            = (empty($_POST['item_number']) ? '' : $_POST['item_number']);
$payment_status         = (empty($_POST['payment_status']) ? '' : $_POST['payment_status']);
$mc_gross               = (empty($_POST['mc_gross']) ? '' : $_POST['mc_gross']);
$payment_currency       = (empty($_POST['mc_currency']) ? '' : $_POST['mc_currency']);
$txn_id                 = (empty($_POST['txn_id']) ? '' : $_POST['txn_id']);
$receiver_email         = (empty($_POST['receiver_email']) ? '' : $_POST['receiver_email']);
$receiver_id            = (empty($_POST['receiver_id']) ? '' : $_POST['receiver_id']);
$quantity               = (empty($_POST['quantity']) ? '' : $_POST['quantity']);
$num_cart_items         = (empty($_POST['num_cart_items']) ? '' : $_POST['num_cart_items']);
$payment_date           = (empty($_POST['payment_date']) ? '' : $_POST['payment_date']);
$first_name             = (empty($_POST['first_name']) ? '' : $_POST['first_name']);
$last_name              = (empty($_POST['last_name']) ? '' : $_POST['last_name']);
$payment_type           = (empty($_POST['payment_type']) ? '' : $_POST['payment_type']);
$payment_status         = (empty($_POST['payment_status']) ? '' : $_POST['payment_status']);
$payment_gross          = (empty($_POST['payment_gross']) ? '' : $_POST['payment_gross']);
$payment_fee            = (empty($_POST['payment_fee']) ? '' : $_POST['payment_fee']);
$settle_amount          = (empty($_POST['settle_amount']) ? '' : $_POST['settle_amount']);
$memo                   = (empty($_POST['memo']) ? '' : $_POST['memo']);
$payer_email            = (empty($_POST['payer_email']) ? '' : $_POST['payer_email']);
$txn_type               = (empty($_POST['txn_type']) ? '' : $_POST['txn_type']);
$payer_status           = (empty($_POST['payer_status']) ? '' : $_POST['payer_status']);
$address_street         = (empty($_POST['address_street']) ? '' : $_POST['address_street']);
$address_city           = (empty($_POST['address_city']) ? '' : $_POST['address_city']);
$address_state          = (empty($_POST['address_state']) ? '' : $_POST['address_state']);
$address_zip            = (empty($_POST['address_zip']) ? '' : $_POST['address_zip']);
$address_country        = (empty($_POST['address_country']) ? '' : $_POST['address_country']);
$address_status         = (empty($_POST['address_status']) ? '' : $_POST['address_status']);
$item_number            = (empty($_POST['item_number']) ? '' : $_POST['item_number']);
$tax                    = (empty($_POST['tax']) ? '' : $_POST['tax']);
$option_name1           = (empty($_POST['option_name1']) ? '' : $_POST['option_name1']);
$option_selection1      = (empty($_POST['option_selection1']) ? '' : $_POST['option_selection1']);
$option_name2           = (empty($_POST['option_name2']) ? '' : $_POST['option_name2']);
$option_selection2      = (empty($_POST['option_selection2']) ? '' : $_POST['option_selection2']);
$for_auction            = (empty($_POST['for_auction']) ? '' : $_POST['for_auction']);
$invoice                = (empty($_POST['invoice']) ? '' : $_POST['invoice']);
$custom                 = (empty($_POST['custom']) ? '' : $_POST['custom']);
$notify_version         = (empty($_POST['notify_version']) ? '' : $_POST['notify_version']);
$verify_sign            = (empty($_POST['verify_sign']) ? '' : $_POST['verify_sign']);
$payer_business_name    = (empty($_POST['payer_business_name']) ? '' : $_POST['payer_business_name']);
$payer_id               = (empty($_POST['payer_id']) ? '' : $_POST['payer_id']);
$mc_currency            = (empty($_POST['mc_currency']) ? '' : $_POST['mc_currency']);
$mc_fee                 = (empty($_POST['mc_fee']) ? '' : $_POST['mc_fee']);
$exchange_rate          = (empty($_POST['exchange_rate']) ? '' : $_POST['exchange_rate']);
$settle_currency        = (empty($_POST['settle_currency']) ? '' : $_POST['settle_currency']);
$parent_txn_id          = (empty($_POST['parent_txn_id']) ? '' : $_POST['parent_txn_id']);
$pending_reason         = (empty($_POST['pending_reason']) ? '' : $_POST['pending_reason']);
$reason_code            = (empty($_POST['reason_code']) ? '' : $_POST['reason_code']); 

// subscription specific vars
$subscr_id           = $_POST['subscr_id'];
$subscr_date       = $_POST['subscr_date'];
$subscr_effective = $_POST['subscr_effective'];
$period1           = $_POST['period1'];
$period2           = $_POST['period2'];
$period3           = $_POST['period3'];
$amount1           = $_POST['amount1'];
$amount2           = $_POST['amount2'];
$amount3           = $_POST['amount3'];
$mc_amount1       = $_POST['mc_amount1'];
$mc_amount2       = $_POST['mc_amount2'];
$mc_amount3       = $_POST['mcamount3'];
$recurring           = $_POST['recurring'];
$reattempt           = $_POST['reattempt'];
$retry_at           = $_POST['retry_at'];
$recur_times       = $_POST['recur_times'];
$username           = $_POST['username'];
$password           = $_POST['password']; 

// auction specific vars
$for_auction           = $_POST['for_auction'];
$auction_closing_date = $_POST['auction_closing_date'];
$auction_multi_item   = $_POST['auction_multi_item'];
$auction_buyer_id        = $_POST['auction_buyer_id']; 

if (!$fp) {
    // HTTP ERROR
} else {
    fputs ($fp, $header . $req);
    while (!feof($fp)) {
        $res = fgets ($fp, 1024);
        if (strcmp ($res, "VERIFIED") == 0) {         

            //create MySQL connection
            $link = @mysql_connect($CONFIG['db_host'], $CONFIG['db_user'], $CONFIG['db_pass'])
            or die("Couldn't connect to MySQL:<br>" . mysql_error() . "<br>" . mysql_errno()); 

            //select database
            $db = @mysql_select_db($CONFIG['db_name'], $link)
            or die("Couldn't select database:<br>" . mysql_error(). "<br>" . mysql_errno()); 

            $fecha = date("m")."/".date("d")."/".date("Y");
            $fecha = date("Y").date("m").date("d"); 

            //check if transaction ID has been processed before
            $checkquery = "select txnid from paypal_payment_info where txnid='".$txn_id."'";
            $sihay = mysql_query($checkquery) or die("Duplicate txn id check query failed:<br>" . mysql_error() . "<br>" . mysql_errno());
            $nm = mysql_num_rows($sihay); 

            if ($nm == 0){ 

                if ($txn_type == "cart"){
                    $strQuery = "insert into paypal_payment_info(paymentstatus,buyer_email,firstname,lastname,street,city,state,zipcode,country,mc_gross,mc_fee,memo,paymenttype,paymentdate,txnid,pendingreason,reasoncode,tax,datecreation) values ('".$payment_status."','".$payer_email."','".$first_name."','".$last_name."','".$address_street."','".$address_city."','".$address_state."','".$address_zip."','".$address_country."','".$mc_gross."','".$mc_fee."','".$memo."','".$payment_type."','".$payment_date."','".$txn_id."','".$pending_reason."','".$reason_code."','".$tax."','".$fecha."')";
                    $result = mysql_query($strQuery) or die("Cart - paypal_payment_info, Query failed:<br>" . mysql_error() . "<br>" . mysql_errno());
                    for ($i = 1; $i <= $num_cart_items; $i++) {
                        $itemname = "item_name".$i;
                        $itemnumber = "item_number".$i;
                        $on0 = "option_name1_".$i;
                        $os0 = "option_selection1_".$i;
                        $on1 = "option_name2_".$i;
                        $os1 = "option_selection2_".$i;
                        $quantity = "quantity".$i; 

                        $struery = "insert into paypal_cart_info(txnid,itemnumber,itemname,os0,on0,os1,on1,quantity,invoice,custom) values ('".$txn_id."','".$_POST[$itemnumber]."','".$_POST[$itemname]."','".$_POST[$on0]."','".$_POST[$os0]."','".$_POST[$on1]."','".$_POST[$os1]."','".$_POST[$quantity]."','".$invoice."','".$custom."')";
                        $result = mysql_query($struery) or die("Cart - paypal_cart_info, Query failed:<br>" . mysql_error() . "<br>" . mysql_errno()); 

                        ##############
                        ### BEGIN YOUR CUSTOM CODE FOR BUY NOW VERIFIED (cart)
                        ############## 

                        ##############
                        ### END YOUR CUSTOM CODE FOR BUY NOW VERIFIED (cart)
                        ##############
                    }
                } else {
                    $strQuery = "insert into paypal_payment_info(paymentstatus,buyer_email,firstname,lastname,street,city,state,zipcode,country,mc_gross,mc_fee,itemnumber,itemname,os0,on0,os1,on1,quantity,memo,paymenttype,paymentdate,txnid,pendingreason,reasoncode,tax,datecreation) values ('".$payment_status."','".$payer_email."','".$first_name."','".$last_name."','".$address_street."','".$address_city."','".$address_state."','".$address_zip."','".$address_country."','".$mc_gross."','".$mc_fee."','".$item_number."','".$item_name."','".$option_name1."','".$option_selection1."','".$option_name2."','".$option_selection2."','".$quantity."','".$memo."','".$payment_type."','".$payment_date."','".$txn_id."','".$pending_reason."','".$reason_code."','".$tax."','".$fecha."')";
                    $result = mysql_query("insert into paypal_payment_info(paymentstatus,buyer_email,firstname,lastname,street,city,state,zipcode,country,mc_gross,mc_fee,itemnumber,itemname,os0,on0,os1,on1,quantity,memo,paymenttype,paymentdate,txnid,pendingreason,reasoncode,tax,datecreation) values ('".$payment_status."','".$payer_email."','".$first_name."','".$last_name."','".$address_street."','".$address_city."','".$address_state."','".$address_zip."','".$address_country."','".$mc_gross."','".$mc_fee."','".$item_number."','".$item_name."','".$option_name1."','".$option_selection1."','".$option_name2."','".$option_selection2."','".$quantity."','".$memo."','".$payment_type."','".$payment_date."','".$txn_id."','".$pending_reason."','".$reason_code."','".$tax."','".$fecha."')") or die("Default - paypal_payment_info, Query failed:<br>" . mysql_error() . "<br>" . mysql_errno()); 

                    ##############
                    ### BEGIN YOUR CUSTOM CODE FOR BUY NOW VERIFIED (simple)
                    ############## 

                    ##############
                    ### END YOUR CUSTOM CODE FOR BUY NOW VERIFIED (simple)
                    ##############
                } 

                echo "Verified";
                mail($CONFIG['notify_email'], "VERIFIED IPN", "$res\n $req\n $strQuery\n $struery\n  $strQuery2"); 

            } else {
                // send an email
                mail($CONFIG['notify_email'], "VERIFIED DUPLICATED TRANSACTION", "$res\n $req \n $strQuery\n $struery\n  $strQuery2");
            } 

            //subscription handling branch
            if ( $txn_type == "subscr_signup"  ||  $txn_type == "subscr_payment"  ) { 

                // insert subscriber payment info into paypal_payment_info table
                $strQuery = "insert into paypal_payment_info(paymentstatus,buyer_email,firstname,lastname,street,city,state,zipcode,country,mc_gross,mc_fee,memo,paymenttype,paymentdate,txnid,pendingreason,reasoncode,tax,datecreation) values ('".$payment_status."','".$payer_email."','".$first_name."','".$last_name."','".$address_street."','".$address_city."','".$address_state."','".$address_zip."','".$address_country."','".$mc_gross."','".$mc_fee."','".$memo."','".$payment_type."','".$payment_date."','".$txn_id."','".$pending_reason."','".$reason_code."','".$tax."','".$fecha."')";
                $result = mysql_query($strQuery) or die("Subscription - paypal_payment_info, Query failed:<br>" . mysql_error() . "<br>" . mysql_errno()); 

                // insert subscriber info into paypal_subscription_info table
                $strQuery2 = "insert into paypal_subscription_info(subscr_id , sub_event, subscr_date ,subscr_effective,period1,period2, period3, amount1 ,amount2 ,amount3,  mc_amount1,  mc_amount2,  mc_amount3, recurring, reattempt,retry_at, recur_times, username ,password, payment_txn_id, subscriber_emailaddress, datecreation) values ('".$subscr_id."', '".$txn_type."','".$subscr_date."','".$subscr_effective."','".$period1."','".$period2."','".$period3."','".$amount1."','".$amount2."','".$amount3."','".$mc_amount1."','".$mc_amount2."','".$mc_amount3."','".$recurring."','".$reattempt."','".$retry_at."','".$recur_times."','".$username."','".$password."', '".$txn_id."','".$payer_email."','".$fecha."')";
                $result = mysql_query($strQuery2) or die("Subscription - paypal_subscription_info, Query failed:<br>" . mysql_error() . "<br>" . mysql_errno()); 

                ##############
                ### BEGIN YOUR CUSTOM CODE FOR SUBSCRIPTION VERIFIED
                ############## 

                ##############
                ### END YOUR CUSTOM CODE FOR SUBSCRIPTION VERIFIED
                ############## 

                mail($CONFIG['notify_email'], "VERIFIED IPN", "$res\n $req\n $strQuery\n $struery\n  $strQuery2"); 

            }         

        // if the IPN POST was 'INVALID'...do this
        } else if (strcmp ($res, "INVALID") == 0) {
            // log for manual investigation
            mail($CONFIG['notify_email'], "INVALID IPN", "$res\n $req");
        }
    }
    fclose ($fp);
}

You’ll need the following SQL too…

# Table structure for table `paypal_cart_info` 	#

CREATE TABLE `paypal_cart_info` (
  `txnid` varchar(30) NOT NULL default '',
  `itemname` varchar(255) NOT NULL default '',
  `itemnumber` varchar(50) default NULL,
  `os0` varchar(20) default NULL,
  `on0` varchar(50) default NULL,
  `os1` varchar(20) default NULL,
  `on1` varchar(50) default NULL,
  `quantity` char(3) NOT NULL default '',
  `invoice` varchar(255) NOT NULL default '',
  `custom` varchar(255) NOT NULL default ''
) TYPE=MyISAM;

# Table structure for table `paypal_subscription_info` #

CREATE TABLE `paypal_subscription_info` (
  `subscr_id` varchar(255) NOT NULL default '',
  `sub_event` varchar(50) NOT NULL default '',
  `subscr_date` varchar(255) NOT NULL default '',
  `subscr_effective` varchar(255) NOT NULL default '',
  `period1` varchar(255) NOT NULL default '',
  `period2` varchar(255) NOT NULL default '',
  `period3` varchar(255) NOT NULL default '',
  `amount1` varchar(255) NOT NULL default '',
  `amount2` varchar(255) NOT NULL default '',
  `amount3` varchar(255) NOT NULL default '',
  `mc_amount1` varchar(255) NOT NULL default '',
  `mc_amount2` varchar(255) NOT NULL default '',
  `mc_amount3` varchar(255) NOT NULL default '',
  `recurring` varchar(255) NOT NULL default '',
  `reattempt` varchar(255) NOT NULL default '',
  `retry_at` varchar(255) NOT NULL default '',
  `recur_times` varchar(255) NOT NULL default '',
  `username` varchar(255) NOT NULL default '',
  `password` varchar(255) default NULL,
  `payment_txn_id` varchar(50) NOT NULL default '',
  `subscriber_emailaddress` varchar(255) NOT NULL default '',
  `datecreation` date NOT NULL default '0000-00-00'
) TYPE=MyISAM;

# Table structure for table `paypal_payment_info` #

CREATE TABLE `paypal_payment_info` (
  `firstname` varchar(100) NOT NULL default '',
  `lastname` varchar(100) NOT NULL default '',
  `buyer_email` varchar(100) NOT NULL default '',
  `street` varchar(100) NOT NULL default '',
  `city` varchar(50) NOT NULL default '',
  `state` char(3) NOT NULL default '',
  `zipcode` varchar(11) NOT NULL default '',
  `memo` varchar(255) default NULL,
  `itemname` varchar(255) default NULL,
  `itemnumber` varchar(50) default NULL,
  `os0` varchar(20) default NULL,
  `on0` varchar(50) default NULL,
  `os1` varchar(20) default NULL,
  `on1` varchar(50) default NULL,
  `quantity` char(3) default NULL,
  `paymentdate` varchar(50) NOT NULL default '',
  `paymenttype` varchar(10) NOT NULL default '',
  `txnid` varchar(30) NOT NULL default '',
  `mc_gross` varchar(6) NOT NULL default '',
  `mc_fee` varchar(5) NOT NULL default '',
  `paymentstatus` varchar(15) NOT NULL default '',
  `pendingreason` varchar(10) default NULL,
  `txntype` varchar(10) NOT NULL default '',
  `tax` varchar(10) default NULL,
  `mc_currency` varchar(5) NOT NULL default '',
  `reasoncode` varchar(20) NOT NULL default '',
  `custom` varchar(255) NOT NULL default '',
  `country` varchar(20) NOT NULL default '',
  `datecreation` date NOT NULL default '0000-00-00'
) TYPE=MyISAM;