Ajax software     Free javascripts 
↑


Main Page

You start by modifying

product.php

to include a reference to

url_redirect.inc.php

, and then call its

fix_category_product_url()

function:

<?php

// load library that handles redirects

require_once ‘include/url_redirect.inc.php’;

// redirect requests proper keyword-rich URLs when not already there

fix_category_product_url();

The

fix_category_product_url()

function is executed every time a product page is loaded, and verifies

if the URL used to reach the page is the “proper” one. The “proper” version of the URL is composed using a

helper function named

get_proper_category_product_url()

:

// redirects to proper URL if not already there

function fix_category_product_url()

{

// obtain the proper URL of the current category/product page

$proper_url = get_proper_category_product_url();

How

get_proper_category_product_url()

works is discussed in a second. For now, just assume the

$proper_url

variable contains something like

http://seophp.example.com/Products/Friends-

Shed-C2/AJAX-PHP-Book-P42.html

. As soon as you obtain this “proper” URL, you verify that the URL

used by the visitor to reach the product page matches:

// 301 redirect to the proper URL if necessary

if (SITE_DOMAIN . $_SERVER[‘REQUEST_URI’] != $proper_url)

{

The

$_SERVER[‘REQUEST_URI’]

returns the URL used to reach the page, without the domain name. For

example, if you navigate to

http://seophp.example.com/product.php?category_id=2&product_

id=42

,

$_SERVER[‘REQUEST_URI’]

will return

/product.php?category_id=2&product_id=42

. By

joining the domain name with this value, you obtain a complete URL.

If there is no match, you do a 301 redirect to the proper URL by setting the necessary header values:

// 301 redirect to the proper URL if necessary

if (SITE_DOMAIN . $_SERVER[‘REQUEST_URI’] != $proper_url)

{

header(‘HTTP/1.1 301 Moved Permanently’);

header(‘Location: ‘ . $proper_url);

exit();

}

Now look at

get_proper_category_product_url()

. This function starts by loading the product and

category IDs passed through the URL in the

$_GET

variable:

// returns the proper keyword-rich URL

function get_proper_category_product_url()

{

// retrieve product and category IDs from the query string

$product_id = $_GET[‘product_id’];

$category_id = $_GET[‘category_id’];

88

Chapter 4: Content Relocation and HTTP Status Codes

c04.qxd:c04 10:40 88

Ajax software     Free javascripts 
→ R7