XML: Delete parent with simplexml_import_dom (PHP) - php

Question

I want to delete those entries where the title matches my $titleArray.
My XML files looks like:
<products>
<product>
<title>Battlefield 1</title>
<url>https://www.google.de/</url>
<price>0.80</price>
</product>
<product>
<title>Battlefield 2</title>
<url>https://www.google.de/</url>
<price>180</price>
</product>
</products>
Here is my code but I don't think that it is working and my IDE says here $node->removeChild($product); -> "Expected DOMNode, got DOMNodeList"
What is wrong and how can I fix that?
function removeProduct($dom, $productTag, $pathXML, $titleArray){
$doc = simplexml_import_dom($dom);
$items = $doc->xpath($pathXML);
foreach ($items as $item) {
$node = dom_import_simplexml($item);
foreach ($titleArray as $title) {
if (mb_stripos($node->textContent, $title) !== false) {
$product = $node->parentNode->getElementsByTagName($productTag);
$node->removeChild($product);
}
}
}
}
Thank you and Greetings!

Answer 1

Most DOM methods that fetch nodes return a list of nodes. You can have several element nodes with the same name. So the result will a list (and empty list if nothing is found). You can traverse the list and apply logic to each node in the list.
Here are two problems with the approach. Removing nodes modifies the document. So you have to be careful not to remove a node that you're still using after that. It can lead to any kind of unexpected results. DOMNode::getElementsByTagName() returns a node list and it is a "live" result. If you remove the first node the list actually changes, not just the XML document.
DOMXpath::evaluate() solves two of the problems at the same time. The result is not "live" so you can iterate the result with foreach() and remove nodes. Xpath expressions allow for conditions so you can filter and fetch specific nodes. Unfortunately Xpath 1.0 has now lower case methods, but you can call back into PHP for that.
function isTitleInArray($title) {
$titles = [
'battlefield 2'
];
return in_array(mb_strtolower($title, 'UTF-8'), $titles);
}
$document = new DOMDocument();
$document->loadXml($xml);
$xpath = new DOMXpath($document);
$xpath->registerNamespace("php", "http://php.net/xpath");
$xpath->registerPHPFunctions('isTitleInArray');
$expression = '//product[php:function("isTitleInArray", normalize-space(title))]';
foreach ($xpath->evaluate($expression) as $product) {
$product->parentNode->removeChild($product);
}
echo $document->saveXml();
Output:
<?xml version="1.0"?>
<products>
<product>
<title>Battlefield 1</title>
<url>https://www.google.de/</url>
<price>0.80</price>
</product>
</products>