Integration Guide
Table Of Contents
- Preface
- Introduction
- Payment Data Transfer
- Instant Payment Notification (IPN)
- Downloadable History Log
- IPN and PDT Variables
- Data Type, Maximum Field Lengths, and URL Encoding
- About These Tables of Variables
- test_ipn Variable in Sandbox
- IPN Variables in All Posts
- Buyer Information
- Basic Information
- Advanced and Custom Information
- Shopping Cart Information
- Currency and Currency Exchange
- Auctions
- Mass Payment
- Subscriptions Variables
- Dispute Notification Variables
- PDT-Specific Variables
- Downloadable History Log Columns and Values
- Country Codes
Payment Data Transfer
PDT Notification Synch
20 August 2005 Order Management Integration Guide
PayPal Account Optional is enabled by default. If the merchant has turned on Payment Data
Transfer and has not disabled PayPal Account Optional, a new user will not be automatically
directed back to the merchant website, but will be given the option to return. When the buyer
clicks Continue, the transaction ID associated with the transaction is sent. The merchant
returns the transaction ID, along with their identity token, and PayPal then sends the merchant
payment information that confirms that the payment is complete. The buyer is directed back to
the merchant site where the transaction information is displayed. However, if the buyer does
not click Continue, they will not be directed back to the merchant's site and PDT will not be
initiated.
PDT Notification Synch
After you have activated PDT, every time a buyer makes a website payment and is redirected
to your return URL, a transaction token is sent via a FORM GET variable to this return URL.
To properly use PDT and display transaction details to your customer, you should read the
transaction token from the variable tx and retrieve transaction details from PayPal by
constructing an HTTPS POST to PayPal. This is called notification synch or synchronization.
Constructing the POST
Here are the guidelines for constructing the PDT HTTPS POST to PayPal for notification
synch:
1. Your POST must be sent to
https://www.paypal.com/cgi-bin/webscr.
2. You must include the cmd variable with the value _notify-synch:
cmd=_notify-synch
3. You must include the transaction token in the variable tx and the value of the transaction
token received via PayPal’s GET:
tx=
value_of_transaction_token
4. You must post your identity token using the variable at and the value of your PDT identity
token:
at=
your_identity_token
For information about the identity token, see “Getting and Using the Identity Token” on
page 19.