How to add a string to some URLs - php

Question

I have a php file that generates an xml feed containing a list of all the products of my e-commerce.
For each of the products, the php file is designed to assign a series of tags (price, title, description etc...). One of these tags is the link of the product on my e-commerce.
Example:
<title> smartphone </title>
<category> electronics </category>
<price> 100 </price>
<link> www.mysite.com/smartphone </link>
This is the part of the code (working) used to extract the link of the product (my e-commerce is made with prestashop):
$link = $item->addChild('LINK', $productobj->getLink();
The thing that I need to do, is to dynamically add some string at the end of the link generated for each product.
For example, if the link is:
www.mysite.com/product-name
I need the link to be like this:
www.mysite.com/product-name?parameter1=abc&parameter2=def&parameter3=ghi
And the parameters need to be adapted based on the value of the tag <category>.
Example:
if the product A has the tag <category>electronics</category>
the string to add at the end of its url would be:
?parameter1=electronics&parameter2=def&parameter3=ghi
if the product B has the tag <category>clothes</category>
the string to add at the end of its url would be:
?parameter1=clothes&parameter2=def&parameter3=ghi
Thanks in advance for your precious help.
Good evening.
EDIT:
I report below more detail of the code used to generate the xml file.
<?php
public function addChildWithCDATA($name, $value = NULL) {
$new_child = $this->addChild($name);
if ($new_child !== NULL) {
$node = dom_import_simplexml($new_child);
$no = $node->ownerDocument;
$node->appendChild($no->createCDATASection($value));
}
return $new_child;
}
}
require_once(dirname(__FILE__) . '/config/config.inc.php');
require_once(dirname(__FILE__) . '/init.php');
$config = Configuration::getMultiple(array('PS_LANG_DEFAULT', 'PS_COUNTRY_DEFAULT'));
$defaultLangId = $config['PS_LANG_DEFAULT'];
$defaultCountryId = $config['PS_COUNTRY_DEFAULT'];
Context::getContext()->language = new Language($defaultLangId);
Context::getContext()->link = new Link();
$products = Db::getInstance(_PS_USE_SQL_SLAVE_)->executeS($query);
$counter = 0;
if ($products) {
$itemlist = new SimpleXMLElementExtended('<?xml version="1.0" encoding="UTF-8"?><ITEMLIST></ITEMLIST>');
foreach ($products as $product) {
$item = $itemlist->addChild('ITEM');
$productobj = new Product($product['id_product'], false, $defaultLangId);
$counter++;
$item->addAttribute('ID', $productobj->id);
$item->addAttribute('CITYID', $defcityID);
$item->addAttribute('CATEGORYID', $product['CATEGORYID']);
$title = $item->addChildWithCDATA('TITLE',trim($productobj->name));
$title = $item->addChildWithCDATA('TEXT',strip_tags($productobj->description));
$email = $item->addChild('EMAIL', $defemail);
$link = $item->addChild('LINK', $productobj->getLink());
}
unset($products);
$success &= file_put_contents(_PS_ROOT_DIR_.'/feed.xml', $itemlist->asXML());
echo "DONE";
} else {
echo "NOTHING FOUND";
}
?>

Answer 1

If you are trying to add the category as a URL parameter, you could use:
$link = $item->addChild('LINK', $productobj->getLink() . "?parameter1=" . $product['CATEGORYID']);