Need help calling variables

[DrByte]

Here's a very basic start to doing canonical URL handling:

IT IS NOT RECOMMENDED TO ADD THIS TO AN ALREADY-INDEXED SITE WITHOUT FIRST CAREFULLY CONSIDERING THE CONSEQUENCES OF DOING SO!!!!

1. At the bottom of init_category_path.php (replacing the ?> if any), add this:

// CANONICAL HANDLING:
// product pages:
if (strstr($current_page, '_info') && isset($_GET['products_id'])) {
  $canonicalLink = zen_href_link($current_page, 'cPath=' . zen_get_generated_category_path_rev(zen_get_products_category_id($_GET['products_id'])) . '&products_id=' . $_GET['products_id']);
}
// category/prod-listing pages:
if ($current_page == 'index' && isset($_GET['cPath'])) {
  $excludeParams = array('zenid', 'action', 'main_page', 'language', 'currency', 'typefilter', 'disp_order', 'page', 'sort', 'alpha_filter_id', 'filter_id');
  $canonicalLink = zen_href_link($current_page, zen_get_all_get_params($excludeParams));
}

2. In /includes/templates/YOUR_TEMPLATE_FOLDERNAME/common/html_header.php
Add the 3 lines highlighted here, as shown:

<base href="<?php echo (($request_type == 'SSL') ? HTTPS_SERVER . DIR_WS_HTTPS_CATALOG : HTTP_SERVER . DIR_WS_CATALOG ); ?>" />
<?php if (isset($canonicalLink) && $canonicalLink != '') { ?>
<link rel="canonical" href="<?php echo $canonicalLink; ?>" />
<?php } ?>

<?php
/**
 * load all template-specific stylesheets, named like "style*.css", alphabetically

There are some who may argue that the 'sort' or 'page' options should be removed from these exclusions. If you feel similarly, you're welcome to change it.