Here’s the rub: to have real value, I need to associate these goals with the keyword/campaign/referrer that sent the visitors to me in the first place. Here’s what I’m thinking should be possible. From my website, just before the user clicks the button to go pay on paypal’s website, I could grab some sort of value (visitorID?) and pop it into a custom variable that paypal would return to me when it calls my IPN script. I could then send that back to Piwik when I trigger the goal via the PiwikTracker.php script. I’m just not certain what value I should grab to passthru to my IPN script, and then what I should add to the PiwikTracker call to make the association between original visitor and the goal.
I’ve searched the forum carefully before posting this - quite surprised that nobody else has raised this issue before. Hopefully this should be an easy one for some of you Piwik guru’s out there. Any help will be very much appreciated!
UPDATE: IPN Paypal tracking How to published!!