ConvertArray.php

<?php
/**
 * Magento
 *
 * NOTICE OF LICENSE
 *
 * This source file is subject to the Open Software License (OSL 3.0)
 * that is bundled with this package in the file LICENSE.txt.
 * It is also available through the world-wide-web at this URL:
 * http://opensource.org/licenses/osl-3.0.php
 * If you did not receive a copy of the license and are unable to
 * obtain it through the world-wide-web, please send an email
 * to license@magentocommerce.com so we can send you a copy immediately.
 *
 * DISCLAIMER
 *
 * Do not edit or add to this file if you wish to upgrade Magento to newer
 * versions in the future. If you wish to customize Magento for your
 * needs please refer to http://www.magentocommerce.com for more information.
 *
 * @copyright   Copyright (c) 2014 X.commerce, Inc. (http://www.magentocommerce.com)
 * @license     http://opensource.org/licenses/osl-3.0.php  Open Software License (OSL 3.0)
 */
namespace Magento\Framework\Convert;

use Magento\Framework\Exception;

/**
 * Convert the array data to SimpleXMLElement object
 */
class ConvertArray
{
    /**
     * Transform an assoc array to \SimpleXMLElement object
     * Array has some limitations. Appropriate exceptions will be thrown
     *
     * @param array $array
     * @param string $rootName
     * @return \SimpleXMLElement
     * @throws Exception
     */
    public function assocToXml(array $array, $rootName = '_')
    {
        if (empty($rootName) || is_numeric($rootName)) {
            throw new Exception('Root element must not be empty or numeric');
        }

        $xmlStr = <<<XML
<?xml version='1.0' encoding='UTF-8' standalone='yes'?>
<$rootName></$rootName>
XML;
        $xml = new \SimpleXMLElement($xmlStr);
        foreach (array_keys($array) as $key) {
            if (is_numeric($key)) {
                throw new Exception('Array root keys must not be numeric.');
            }
        }
        return self::_assocToXml($array, $rootName, $xml);
    }

    /**
     * Convert nested array into flat array.
     *
     * @param array $data
     * @return array
     */
    public static function toFlatArray($data)
    {
        foreach ($data as $key => $value) {
            if (is_array($value)) {
                $value = self::toFlatArray($value);
                unset($data[$key]);
                $data = array_merge($data, $value);
            }
        }
        return $data;
    }

    /**
     * Function, that actually recursively transforms array to xml
     *
     * @param array $array
     * @param string $rootName
     * @param \SimpleXMLElement $xml
     * @return \SimpleXMLElement
     * @throws Exception
     */
    private function _assocToXml(array $array, $rootName, \SimpleXMLElement &$xml)
    {
        $hasNumericKey = false;
        $hasStringKey = false;
        foreach ($array as $key => $value) {
            if (!is_array($value)) {
                if (is_string($key)) {
                    if ($key === $rootName) {
                        throw new Exception('Associative key must not be the same as its parent associative key.');
                    }
                    $hasStringKey = true;
                    $xml->{$key} = $value;
                } elseif (is_int($key)) {
                    $hasNumericKey = true;
                    $xml->{$rootName}[$key] = $value;
                }
            } else {
                self::_assocToXml($value, $key, $xml->{$key});
            }
        }
        if ($hasNumericKey && $hasStringKey) {
            throw new Exception('Associative and numeric keys must not be mixed at one level.');
        }
        return $xml;
    }
}