Integration Guide

PayPal Payments Standard Integration Guide June 2012 441
HTML Variables for PayPal Payments Standard
HTML Variables for the Instant Update API
A
HTML Variables for the Instant Update API
HTML variables for the Instant Update API set up the Cart Upload command for the
Instant Update API callback. Establish your own Instant Update callback server before you
use these variables.
Instant Update Variables to Set Up a Payment for the Instant Update API
Some Instant Update variables set up the Cart Upload to use your callback server. Include the
following required variables in the Cart Upload command to have PayPal send Instant Update
requests to your callback server. Include the following optional variables when appropriate.
HTML Variables to Set Up an Instant Update Payment
Name
Required
or
Optional Description
Character
Length
callback_url Required The URL of your Instant Update callback server 1024
callback_timeou
t
Required The timeout in seconds for callback responses from your
Instant Update callback server. After exceeding the timeout,
PayPal uses the fallback values on the Review Your Payment
page for tax, shipping, and insurance.
Allowable values are 1-6. PayPal recommends the value 3.
IMPORTANT: Use values other than 3 only when instructed
to do so by your PayPal representative..
1
callback_versio
n
Required The version of the Instant Update API that your callback
server uses.
fallback_tax_am
ount
Optional Tax amount to use as a fallback, if the callback response
times out
fallback_shippi
ng_option_name_
x
Required Name and label of shipping option
x to use as a fallback, if
the callback response times out. For example, “Express 2
days”. You can include a maximum of 10 shipping options
as fallbacks. Substitute
x with ordinal numbers, starting with
0.
Iinclude 1 instance of this variable, with its index (
x) set to 0.
If you include just 1 instance, include
fallback_shipping_option_is_default_x with its
index (
x) set to 0 and its value set to 1.
Allowable values for
x are 0-9.
50
fallback_shippi
ng_option_amoun
t_
x
Required Shipping amount for option
x to use as a fallback, if the
response times out.
Allowable values for
x are 0-9.