xml to extract data in php

Unfortunately you cannot properly convert XML attributes or partial NS attributes with json_encode. Just for fun i wrote simple example how you can convert XML into some tricky PHP array with keep all data. Output format is little different from your expectation and my goal was to share example how to get data.

<?php
declare(strict_types=1);

namespace Acme\StackExchange\Helper;

use Magento\Framework\App\Helper\AbstractHelper;

class XmlParser extends AbstractHelper
{
    public function parseString(string $xml, array $nsList = []): array
    {
        $xmlElement = simplexml_load_string($xml);
        if ($xmlElement) {
            return $this->parse($xmlElement, $nsList);
        }

        return [];
    }

    public function parse(\SimpleXMLElement $xmlNode, array $nsList = [], bool $isRoot = true): array
    {
        $output = [];

        if (!$isRoot) {
            if (count($xmlNode->attributes()) > 0) {
                $output['$'] = [];
                foreach ($xmlNode->attributes() as $key => $value) {
                    $output['$'][$key] = (string)$value;
                }
            }

            $textValue = trim((string)$xmlNode);
            if (!empty($textValue)) {
                $output['_'] = $textValue;
            }

            $childrenList = [$xmlNode->children()];
            if ($nsList) {
                foreach ($nsList as $ns) {
                    $childrenList[] = $xmlNode->children($ns, true);
                }
            }

            foreach ($childrenList as $children) {
                foreach ($children as $childNode) {
                    $childName = $childNode->getName();
                    if (!array_key_exists($childName, $output)) {
                        $output[$childName] = [];
                    }
                    $output[$childName][] = $this->parse($childNode, $nsList, false);
                }
            }
        } else {
            $nodeName = $xmlNode->getName();
            $output[$nodeName] = [$this->parse($xmlNode, $nsList, false)];
        }

        return $output;
    }
}

How to use

$helper =\Magento\Framework\App\ObjectManager::getInstance()
            ->get(\Acme\StackExchange\Helper\XmlParser::class);
var_export($helper->parseString($xml, ['video']));

Example output:

array (
  'urlset' => 
  array (
    0 => 
    array (
      'url' => 
      array (
        0 => 
        array (
          'loc' => 
          array (
            0 => 
            array (
              '_' => 'https://www.google.com',
            ),
          ),
          'video' => 
          array (
            0 => 
            array (
              'thumbnail_loc' => 
              array (
                0 => 
                array (
                  '_' => 'abc.jpg',
                ),
              ),
              'title' => 
              array (
                0 => 
                array (
                  '_' => 'abc',
                ),
              ),
              'description' => 
              array (
                0 => 
                array (
                  '_' => 'Watch thousands of 4k videos..',
                ),
              ),
              'player_loc' => 
              array (
                0 => 
                array (
                  '$' => 
                  array (
                    'autoplay' => 'ap=1',
                  ),
                  '_' => 'test.mp4',
                ),
              ),
              'duration' => 
              array (
                0 => 
                array (
                  '_' => '470',
                ),
              ),
              'publication_date' => 
              array (
                0 => 
                array (
                  '_' => '2022-06-18T14:24:05+00:00',
                ),
              ),
              'family_friendly' => 
              array (
                0 => 
                array (
                  '_' => 'no',
                ),
              ),
              'category' => 
              array (
                0 => 
                array (
                ),
              ),
              'platform' => 
              array (
                0 => 
                array (
                  '$' => 
                  array (
                    'relationship' => 'allow',
                  ),
                  '_' => 'web',
                ),
              ),
              'live' => 
              array (
                0 => 
                array (
                  '_' => 'no',
                ),
              ),
            ),
          ),
        ),
      ),
    ),
  ),
)