Integrate third party tax table into paypal using php/mysql - php

Question

I am using Website Payments Standard and have numerous zip codes I'd like to apply for tax rates (more than I can manually input one at a time into Paypal's standard tax rules). Is there a way for the checkout solution to connect to my database (a mysql database) where I have the zip codes + tax rates? Is it possible for all this to happen in the shopping cart experience?

Answer 1

Yes, you can use the PayPal Instant Update API.
In a nutshell; you'll need to set up a script on your server which accepts a POST with shipping address data from PayPal, and requires you to return an appropriate response as output including the tax/shipping amount. This will then be used during checkout as the shipping/tax amount.
Have a look at https://cms.paypal.com/us/cgi-bin/?cmd=_render-content&content_ID=developer/e_howto_html_Appx_websitestandard_htmlvariables#id09CA80W0Z5Z and https://cms.paypal.com/us/cgi-bin/?cmd=_render-content&content_ID=developer/e_howto_api_nvp_r_CallbackAPI
For Website Payments Standard, base a button off of the following form code:
<form action="https://www.sandbox.paypal.com/cgi-bin/webscr" method="post" target="paypal">
<input type="hidden" name="upload" value="1">
<input type="hidden" name="cmd" value="_cart">
<input type="hidden" name="business" value="name#test.com">
<input type="hidden" name="currency_code" value="USD">
<input type="hidden" name="return" value="https://link-to-your-return-script.php">
<!--item 1 -->
<input type="hidden" name="quantity_1" value="1">
<input type="hidden" name="item_name_1" value="Gladiator - Extended">
<input type="hidden" name="item_number_1" value="3425654">
<input type="hidden" name="amount_1" value="10">
<!--item 2 -->
<input type="hidden" name="quantity_2" value="1">
<input type="hidden" name="item_name_2" value="Casino - Extended ">
<input type="hidden" name="item_number_2" value="4354567754">
<input type="hidden" name="amount_2" value="2">
<!--CALLBACK PARAMETERS -->
<input type="hidden" name="callback_url" value="https://link-to-your-callback-script.php">
<input type="hidden" name="callback_timeout" value="4">
<input type="hidden" name="callback_version" value="61"> <!--Required! -->
<input type="hidden" name="fallback_shipping_option_name_0" value="Option 1">
<input type="hidden" name="fallback_shipping_option_amount_0" value="1">
<input type="hidden" name="fallback_shipping_option_is_default_0" value="1">
<input type="hidden" name="fallback_shipping_option_name_1" value="Option 2">
<input type="hidden" name="fallback_shipping_option_amount_1" value="3">
<input type="hidden" name="fallback_shipping_option_is_default_1" value="0">
<input type="hidden" name="fallback_insurance_option_offered" value="0">
<!--CALLBACK PARAMETERS END-->
<input type="submit" value="Upload cart">
</form>
Whenever a buyer checks out, you will receive a POST with data on https://link-to-your-callback-script.php
The following is an example POST payload which you may receive:
CallbackRequest:
METHOD=CallbackRequest
CALLBACKVERSION=57
TOKEN=EC-7TF47275R51235219
LOCALECODE=en_US
CURRENCYCODE=USD
L_NAME0=Item name
L_NUMBER0=0123456789
L_DESC0=Description of item goes here
L_AMT0=1.00
L_QTY0=1
L_ITEMWEIGHTUNIT0=
L_ITEMWEIGHTVALUE0=0
L_ITEMHEIGHTUNIT0=
L_ITEMHEIGHTVALUE0=0
L_ITEMWIDTHUNIT0=
L_ITEMWIDTHVALUE0=0
L_ITEMLENGTHUNIT0=
L_ITEMLENGTHVALUE0=0
SHIPTOSTREET=1 Main St
SHIPTOCITY=San Jose
SHIPTOSTATE=CA
SHIPTOCOUNTRY=US
SHIPTOZIP=95131
SHIPTOSTREET2=
After which you must calculate the appropriate tax / shipping amounts, and return a proper CallBackResponse message.
For example;
CallBackResponse:
METHOD=CallbackResponse&
OFFERINSURANCEOPTION=true&
L_SHIPPINGOPTIONLABEL0=UPS Next Day Air TEST5&
L_SHIPPINGOPTIONAMOUNT0=1.00&
L_TAXAMT0=0.00&
L_INSURANCEAMOUNT0=0.00&
L_SHIPPINGOPTIONISDEFAULT0=false&
L_SHIPPINGOPTIONLABEL1=UPS Express 2 Days TEST4&
L_SHIPPINGOPTIONAMOUNT1=1.50&
L_TAXAMT1=0.00&
L_INSURANCEAMOUNT1=0.0&
L_SHIPPINGOPTIONISDEFAULT1=true&
L_SHIPPINGOPTIONLABEL2=UPS Ground2 to 7 Days TEST3&
L_SHIPPINGOPTIONAMOUNT2=1.50&
L_TAXAMT2=0.00&
L_INSURANCEAMOUNT2=0.00&
L_SHIPPINGOPTIONISDEFAULT2=false
Once PayPal has received this information, it will update the shipping/tax charges automatically.
For more information, see https://cms.paypal.com/us/cgi-bin/?cmd=_render-content&content_ID=developer/e_howto_api_ECInstantUpdateAPI