Hi,
Please allow me to clarify things about paypal API. Before implementing any payment processors that utilizes an IPN class or script, script should be tested in paypal sandbox environment.
Suggested steps to take.
1. Create a paypal sandbox account.
2. Login to your sandbox account and create a seller and buyer accounts. This is extremely important. Your test transactions will be made between these two.
3. Select which IPN script you will be using. For example, this one.
Follow the IPN script installation instructions. Most of them have some kind of database to record the payment made and payment received.
Write a php script that will check the subscription renewal date. You can set up a cron job for this script to run once a day. If the script finds any account due for renewal of billing, the script will trigger the IPN script to send payment request to paypal. The IPN listener will then email you for confirmations and errors.
Example of integrated form using an IPN class
<form action=”https://www.paypal.com/cgi-bin/webscr” method=”post”>
<input type=”hidden” name=”cmd” value=”_xclick”>
<input type=”hidden” name=”business” value=” seller@yourDomain.com “>
<input type=”hidden” name=”item_name” value=”ipad”>
<! -- the rest of the form here --->
Convert the above for subscription form
<form action=”https://www.paypal.com/cgi-bin/webscr” method=”post”>
<input type=”hidden” name=”cmd” value=”_xclick-subscriptions”>
<input type=”hidden” name=”business” value=” seller@yourDomain.com “>
<input type=”hidden” name=”item_name” value=”Your service yearly subscription”>
<input type=”hidden” name=”return” value=”yourDomain.com/ipnlistener.php “>
Notice the return value? yourDomain.com/ipnlistener.php. This is the file …