Integration Guide

Table Of Contents
Express Checkout Integration Guide October 2009 79
Implementing the Instant Update API
Using the Callback
7
Callback Request
The PayPal sends the parameters in the callback request to the location you specified for
CALLBACKURL. The callback request parameters include:
z The line-item details you sent in the call to SetExpressCheckout. PayPal also sends
back any line-item description details you may have specified such as the
L_ITEMWEIGHTUNIT1 and L_ITEMWEIGHTVALUE1 values shown in the example below.
By passing this data back to you, PayPal expedites your callback response by eliminating
the need for you to perform a database query to get this information.
z The shipping address of the buyer.
Using the information in the callback request, you can calculate the rates and options yourself
or send the information in an API call to your carrier to perform the calculations for you.
This is an example callback request.
METHOD=CallbackRequest
&CALLBACKVERSION=57.0
&TOKEN=EC-0EE85728D547104V
&CURRENCYCODE=USD
&LOCALECODE=en_US
&L_NAME0=10% Decaf Kona Blend Coffee
&L_NUMBER0=623083
&L_DESC0=Size: 8.8-oz
&L_AMT0=9.95
&L_QTY0=2
&L_NAME1=Coffee Filter bags
&L_NUMBER1=6230
&L_DESC1=Size: Two 24-piece boxes
&L_AMT1=39.70
&L_QTY1=2
&L_ITEMWEIGHTUNIT1=lbs
&L_ITEMWEIGHTVALUE1=0.5
&SHIPTOSTREET=1 Main St
&SHIPTOCITY=San Jose
&SHIPTOSTATE=CA
&SHIPTOCOUNTRY=US
&SHIPTOZIP=95131
&SHIPTOSTREET2
Callback Response
Each time your web service receives a request from PayPal, it must process the request and
respond with the appropriate details.
This is an example callback response.