How can I find out which file this IPN request goes to?

Question

I am in the process of moving from a plug-in IPN package (Valanx for Joomla) to a custom built one in PHP.

The problem is that there is no way to change the IPN address for existing subscribers! I'm not sure why PayPal has made this param fixed for eternity but it's causing us some headaches. So now we have to put some code in the existing IPN receiver to forward it to our new receiver - so that old subscribers get updated into the new system.

I can't find the file I have to modify. It is lost somewhere in the maze of Joomla files and plug-ins. The current plug-in uses a query string as it's receiver address http://mywebsite.com/index.php?option=com_acctexp&task=paypal_subscriptionnotification&Itemid=99999999'

My question is this: How do I find out which file to modify to forward the existing IPNs to our new system?

Or perhaps someone has another suggestion of how to handle this rather that forwarding the IPN (which seems rather clumsy to me).

Answer 1

Under normal Joomla! conventions (ie if the extension is writting following the MVC) the URL would break down as follows.

option=com_acctexp - in the front end maps to the directory /components/com_acctexp/

task=paypal_subscriptionnotification is the name of the method in one of the controller files. However, from memory Valanx's AEC product didn't follow this convention.

In a modern extension you would see task=controller.method syntax which would indicate the specific controller file and the method invoked in it.

You will probably find it in their processors (or is it called paymentgateways directory) within the main com_acctexp directory. I'd suggest looking for a paypal.php or paypal_subscriptions.php file in that directory.

Sorry I can't be more specific it's been a few years since with dumped replaced that product.

Answer 2

You should be able to log into your PayPal account, and go into your IPN history within your account. If you click on one of the past IPN's that was sent out, it will give you the URL that you sent it to. This will tell you where the file is located at that you need to modify. Keep in mind the IPN history only goes back 28 days, so it would have to be for an IPN that was completed in the last 28 days.