PHP and MySQL Web Development 4th Ed-tqw-_darksiderg

Implementing an Administration Interface
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You process the user’s card and, if all is successful, destroy her session.
The card processing function as it is written simply returns true. If you were actually
implementing it, you would need to perform some validation (checking that the expiry
date was valid and the card number well formed) and then process the actual payment.
When you set up a live site, you need to make a decision about what transaction
clearing mechanism you want to use.You can
n Sign up with a transaction clearing provider.There are many, many alternatives
here depending on the area you live in. Some of them offer real-time clearing, and
others don’t.Whether you need live clearing depends on the service you are offering.
If you are providing a service online, you will most likely want it; if you are
shipping goods, it’s less crucial. Either way, these providers relieve you of the
responsibility of storing credit card numbers.
n Send a credit card number to yourself via encrypted email, for example, by
using Pretty Good Privacy (PGP) or Gnu Privacy Guard (GPG), as covered in
Chapter 18.When you receive and decrypt the email, you can process these transactions
manually.
n Store the credit card numbers in your database.We do not recommend this option
unless you really, seriously know what you’re doing with system security. Read
Chapter 18 for more details about why this is a bad idea.
That’s it for the shopping cart and payment modules.
Implementing an Administration Interface
The administration interface we implemented is very simple.We just built a Web interface
to the database with some front-end authentication.This interface uses much of the
same code as used in Chapter 27.We included it here for completeness, but with little
discussion.
The administration interface requires a user to log in via the login.php file, which
then takes him to the administration menu, admin.php.The login page is shown in
Figure 28.11. (We omitted the login.php file here for brevity; it’s almost exactly the
same as the one in Chapter 27. If you want to look at it, it’s on the CD-ROM.) The
administration menu is shown in Figure 28.12.