The next step in the evolution of the Coffee site is to incorporate the payment processing system that will allow customers to complete their orders. For this project, I’ve chosen Authorize.net as the payment processor. The first several pages of the chapter talk about Authorize.net and walk you through setting up a test account there. Once you have a test account, you can write the entire checkout process.
The checkout process consists of four parts:
1. Take and validate the shipping information.
2. Take and validate the billing information.
3. Process the payment.
4. Wrap it up (update the database, let the customer know, and so on).
This chapter probably has the most complicated code of any in the book. But this chapter also ...