e-Commerce can be integrated with several payment gateways around the globe. Its just matter of doing so.
Creating a payment gateway means creating a new module. Your module should be named appropriately so that others will recognize it and desire to use it as well. For the purposes of this tutorial, we shall call ours *mygateway*.
COMING SOON!
Your module should contain the following functions:
function mygateway_menu -Put all your menu items here, just like with any other Drupal module
function mygateway_help- Provide some description of your module
function mygateway_settings- This will be the settings that you need to use your payment gateway provider, such as username and password, plus any other settings that control HOW your module should behave either within Drupal or as it interacts with your payment gateway provider.
function mygateway_paymentapi- This is the hook into e-Commerce that displays your payment gateway as a method of payment. You can have more than one method of payment available to your store, but I haven't found a way of having more than one method of payment available within a single module. (yet!)
function mygateway_ec_transactionapi- This hooks your module into the e-Commerce transactions.
function mygateway_save- This is your storage method to save any information about this transaction with the payment gateway responses.
function mygateway_delete- This deletes any stored information about the transaction and payment gateway responses.
function mygateway_goto- This puts your payment form into the checkout process.
function mygateway_form- This is your payment form that gathers the information
function mygateway_form_validate- This is your validation function for the payment gateway that takes the form information and validates it.
function mygateway_form_submit- This submits your information to the eCommerce transaction system as well as the payment gateway.
This is just a start here- we hope it helps!