Web Database Applications With Php And Mysql (2nd Edition) [Electronic resources] نسخه متنی

17.1 Code Overview

The
customer management process is provided by the
customer/details.php

,
customer/validate.php
, and
customer/receipt.php
scripts.

The script customer/details.php presents a form
to both new customers and members who are updating their details. The
form collects and inserts or updates data that is stored by
customer/validate.php into the
customer table. The
customer table was created with the following
statement:

CREATE TABLE customer (
cust_id int(5) NOT NULL,
surname varchar(50),
firstname varchar(50),
initial char(1),
title_id int(3),
address varchar(50),
city varchar(50),
state varchar(20),
zipcode varchar(10),
country_id int(4),
phone varchar(15),
birth_date char(10),
PRIMARY KEY (cust_id)
) type=MyISAM;

The form is initially empty if the user isn't logged
in, and hasn't previously attempted and failed
validation. If the user is logged in and validation
hasn't previously failed, the form is pre-filled
with her details from the customer table.
Finally, regardless of whether a user is logged in or not, if data
has failed validation, the invalid data is displayed for amendment.
The customer form, showing errors from failed validation, is shown
rendered in a Mozilla browser in Figure 17-1.

Figure 17-1. The customer form rendered in a Mozilla browser

For new members, the form requires an email address that is used as
the login name of the user and a password for future visits to the
site. This information is stored in the
users
table that was created with the
following statement:

CREATE TABLE users (
cust_id int(5) NOT NULL,
user_name varchar(50) NOT NULL,
password varchar(32) NOT NULL,
PRIMARY KEY (user_name),
KEY password (password),
KEY cust_id (cust_id)
) type=MyISAM;

The table is identical to the users table
discussed in Chapter 11, except
we've added two extra indexes for fast searching by
password and cust_id.

Two lookup tables are used for displaying and selecting the
user's country and title. The
customer table stores the identifiers
title_id and country_id, and
these identifiers are the primary keys of the
titles and countries lookup
tables, respectively. The contents of both lookup tables are
displayed as drop-down lists using the HTML
<select> element and make use of our
winestoreFormTemplate select
blocks. The tables were created with the following statements:

CREATE TABLE titles (
title_id int(2) NOT NULL,
title char(10),
PRIMARY KEY (title_id)
) type=MyISAM;
CREATE TABLE countries (
country_id int(4) NOT NULL,
country char(30) NOT NULL,
PRIMARY KEY (country_id),
KEY (country)
) type=MyISAM;

Passwords are digested so as not to be stored in plaintext anywhere;
they're between 6 and 8 characters in length when
entered by the user, but the digest process generates a string of 32
characters. For customers who are amending their details, the
password and email input widgets are omitted from the customer form.
If the user wants to change his password, he can use the change
password feature discussed in Chapter 20. User
names can't be changed; this is a feature you might
add to a real-world application.

The
customer/validate.php
script validates the
customer data that's passed through from the form
using the POST method. If the customer is new and
validation succeeds, the script inserts the new customer into the
customer table, adds the new user to the
users table, logs the user in, and redirects to
the customer receipt script
customer/receipt.php. If the customer is
amending her details and validation succeeds, the script updates her
row in the customer table and redirects to the
receipt script.

On validation failure, customer/validate.php
redirects to
customer/details.php,

where the validation
errors are reported as batch errors that are interleaved with the
form widgets. To display errors and the previously entered data, the
script makes use of two session arrays that are populated by
customer/validate.php as part of the validation
process. This process is discussed in Chapter 10.

The
customer/receipt.php
script displays the
customer details by querying the customer table
and retrieving the details for the user who's
currently logged in. Users can't view customer
receipts if they're not logged in. An example
receipt page is shown in Figure 17-2.

Figure 17-2. A customer receipt page rendered in the Mozilla browser

We reuse this template-based data entry process, validation, and
receipt framework in other parts of the winestore. For example, the
code is adapted for password changing and credit card data entry. The
framework is explained in Chapter 16.