PayPal Express Checkout

This document is a technical introduction to using the PayPal Express checkout via DataCash. Further detailed information to assist integration with the Bank Card Service is available in the Developers Guide.

The PayPal Express Checkout Service

This Service enables you to offer PayPal as an alternative payment method on your website.  It can be presented in the checkout flow before other payment types (Express Checkout Shortcut) or as an alternative to other payment types (Express Checkout Mark).  There are up to three parts to a PayPal Express Checkout transaction as detailed below.

Re-direct

The first part of the express checkout transaction is to get a token from PayPal to use during the transaction process.  This token is stored by DataCash and sent with subsequent transactions.  It remains valid for 3 hours therefore the transaction must be completed within this time period.  Once the token has been received the PayPal user should be re-directed to the PayPal website to confirm the payment.

PayPal User Completes Payment Details

Once re-directed the PayPal user has the opportunity to confirm the payment and, if necessary, confirm the shipping address for the goods.

Re-Direct back to Merchant Site

When the PayPal user has confirmed their order they are re-directed back to the merchant’s site.  The details of the transaction including shipping details can now be requested from PayPal.  The merchant can then complete the transaction.

Refunds

It is also possible to refund PayPal transactions.

 

Requirements

Before you can go live with this service, you will need the following:

  • an account with DataCash configured for PayPal
  • a PayPal Merchant account
  • the ability to send XML transactions to our servers

Transaction Processing Models

These are the transaction types available for the PayPal Express Checkout Service:


Transaction Type

Effect

set_express_checkout

Initiates transaction

get_express_checkout

Obtains results of transaction

do_express_checkout

Transfers funds from PayPal User to PayPal Merchant Account

txn_refund

Returns funds from the Merchants PayPal account back to the Users PayPal account

Performing PayPal Express Checkout Transactions

All types require specific minimum information to be provided. In addition to those listed, each requires a client and password - these are security details which identify your account.

Token

  • Amount – The value of the transaction
  • Merchant Reference – A unique reference generated by the merchant system
  • Method – a method type of set_express_checkout
  • Header Style – details of the header style for the PayPal Payment page when the user is re-directed
  • Return URL – the URL the user will be returned to following confirmation of the payment
  • Cancel URL – the URL the user will be returned to if they do not want to complete the payment using PayPal

Get Details

  • Method – a method type of get_express_checkout_details
  • DataCash Reference – the DataCash reference as returned from the initial transaction
  • Merchant Reference – a unique reference generated by the merchant system

Settle Funds

  • Amount – the final amount to be settled
  • Merchant Reference – a unique reference generated by the merchant system
  • DataCash Reference – the DataCash Reference returned from the initial transaction
  • Method – a method type of do_express_checkout_payment

Refunding a PayPal Transaction

To refund PayPal transaction, the following information is required:

  • the original DataCash reference for the PayPal transaction
  • the transaction type – txn_refund
  • the amount

Response Codes

There are two basic Response types for all transactions.

  • Accepted
  • Errors

Accepted

A successful response indicates that the PayPal transaction was accepted.

Errors

A complete list of Response Codes for this service is available here. The Support Centre also contains extensive examples for most error codes. Illustrations are given to demonstrate how they would appear in both Reporting and an XML Response. Suggestions are also given to help you prevent them from occurring.

Reporting

The PayPal transactions are detailed in the PayPal section of the DataCash Reporting system. There are three main pages:

  • Summary - gives a summary of PayPal transactions
  • List - shows specific details of the PayPal transactions
  • Details - shows full details of each PayPal transaction

The Support Centre contains full hints and tips to help you get the most out of Reporting.