Using PHP with Google serial notification (IPN) - php

Question

I'm trying to figure out how to get this working with PHP. I have a working IPN for paypal that is less than 20 lines of code to get the data I need. I have tried reading the Google docs but they are either way too specific or way too general. There is some sample code, which is about 1300 lines in 5 files and I can't make sense of it. I just need a handful of vars back from a completed transaction, nothing more. Is it possible to do this with a few lines of code (and I mean without 1300 lines worth of "include" files) or is Google Checkout's process really that bulky?

Answer 1

Here's a bit of code I started. Not yet finished.
It works perfectly.
All you need to do is take the data Google sends back and this code writes to a file and use it to insert into your sales table send notification of payment received to customer and so on.
The trick is that when Google sends you a post you must call back with and Authorization header or it will not take it in consideration.
function post2google($url, $timeout = 30, $port = 80, $buffer = 128) {
$mid = "123456789";
$mky = "qwertyuiop";
$aut = base64_encode($mid . ":" . $mky);
$arr = parse_url($url);
$ssl = "";
if($arr['scheme'] == "https") $ssl = "ssl://";
$post = "POST " . $arr['path'] . " HTTP/1.1\r\n";
$post .= "Host: " . $arr['host'] . "\r\n";
$post .= "Authorization: Basic " . $aut . "\r\n";
$post .= "Content-Type: application/xml; charset=UTF-8\r\n";
$post .= "Accept: application/xml; charset=UTF-8\r\n";
$post .= "Content-Length: " . strlen($arr['query']) . "\r\n";
$post .= "Connection: Close\r\n";
$post .= "\r\n";
$post .= $arr['query'];
$f = fsockopen($ssl . $arr['host'], $port, $errno, $errstr, $timeout);
if(!$f)
return $errstr . " (" . $errno . ")";
else{
fputs($f, $post);
while(!feof($f)) { $echo .= #fgets($f, $buffer); }
fclose($f);
return $echo;
}
}
$re = post2google("https://checkout.google.com/api/checkout/v2/reportsForm/Merchant/123456789?_type=notification-history-request&serial-number=" . $_REQUEST['serial-number'], 3, 443);
$re = str_replace("&", "\n", $re) . "\n\n--\n\n";
file_put_contents("gpn.txt", $re, FILE_APPEND);

Answer 2

I've gotten it to work, and here's the skeleton of my code that can be used to handle HTTP notifications/responses. This was obviously derived from tntu's example above. (Thanks!)
//incoming data is in the var $_POST['serial-number']
//"send" the response to acknowledge the serial number that google talks about all over but never explains how
echo "_type=notification-acknowledgment&serial-number=".$_POST['serial-number'];
//now we need to call google's server and ask for this transaction's data:
//you'll need to change your merchant id in the $url and $mid vars, and your merchant key in the $mky var
$url = "https://sandbox.google.com/checkout/api/checkout/v2/reportsForm/Merchant/1234567890?_type=notification-history-request&serial-number=" . $_REQUEST['serial-number'];
$mid = "1234567890";
$mky = "ABCDEFGHIJK";
$aut = base64_encode($mid . ":" . $mky);
$arr = parse_url($url);
$ssl = "";
if($arr['scheme'] == "https") $ssl = "ssl://";
$post = "POST " . $arr['path'] . " HTTP/1.1\r\n";
$post .= "Host: " . $arr['host'] . "\r\n";
$post .= "Authorization: Basic " . $aut . "\r\n";
$post .= "Content-Type: application/xml; charset=UTF-8\r\n";
$post .= "Accept: application/xml; charset=UTF-8\r\n";
$post .= "Content-Length: " . strlen($arr['query']) . "\r\n";
$post .= "Connection: Close\r\n";
$post .= "\r\n";
$post .= $arr['query'];
//now we actually make the request by opening a socket and calling Google's server
$f = fsockopen($ssl . $arr['host'], 443, $errno, $errstr, 30);
if(!$f){
//something failed in the opening of the socket, we didn't contact google at all, you can do whatever you want here such as emailing yourself about it and what you were trying to send, etc
#mail("troubleshooting#yourdomain.com","Google IPN - HTTP ERROR ",$errstr . " (" . $errno . ")\n\n\n".$arr['query']);
}else{
//the socket was opened, send the request for the order data:
fputs($f, $post); // you're sending
while(!feof($f)) { $response .= #fgets($f, 128); } //google replies and you store it in $response
fclose($f); //close the socket, we're done talking to google's server
$spl=strpos($response,"_type="); //parse the type because parse_str won't catch it
if ($spl!==false){
$spl2=strpos($response,"&",$spl);
$ordertype=substr($response,($spl+6),($spl2-$spl)-6);
}//$ordertype will tell you which type of notification is being sent, new-order-notification, risk-information-notification, etc
$subresponse=substr($response,$spl2+1); //put the rest of it into an array for easy access
parse_str($subresponse,$order);//you can now access google's response in $order[] vars
//IMPORTANT: dots in Google's field names are replaced by underscore, for example:
// $order['google-order-number'] and $order['buyer-billing-address_address1'] NOT $order['buyer-billing-address.address1']
//order field names are shown here:
//https://developers.google.com/checkout/developer/Google_Checkout_HTML_API_Notification_API#order_summary
//this is the point where you will want to use the data contained in $order[] to create a new record in your database or whatever.
//NOTE: be sure to store and check for duplicates using the google-order-number because you will get multiple notifications from google regarding the same order
if (strtoupper($order['order-summary_financial-order-state']) == "CHARGEABLE"){
//CHARGEABLE is what indicates it is safe to create a login for the user (if you are delivering digital goods)
// insert into db, and/or email user with key or download url
}
}