Ошибка при добавлении плагина товара

[2018-04-05 11:49:50] (ERROR @ C:\OpenServer\domains\antikmagaz-new.ru\core\components\minishop2\model\minishop2\minishop2.class.php : 558) PHP warning: Invalid argument supplied for foreach()

<?php
return array (
    'xpdo_meta_map' => array (
        'msProductData' => require_once dirname(__FILE__) .'/model/msproductdata.map.inc.php',
    ),
    'manager' => array (
        'msProductData' => MODX_ASSETS_URL . 'components/minishop2/plugins/nalichie/msproductdata.js',
    ),
);

<?php
return array (
	'fields' => array (
		'availability' => 1,
	)
	,'fieldMeta' => array (
		'availability' => array (
			'dbtype' => 'tinyint',
			'precision' => '1',
			'attributes' => 'unsigned',
			'phptype' => 'boolean',
			'null' => false,
			'default' => 1,
		),
	),
);

miniShop2.plugin.availability = {
	getFields: function(config) {
		return {
			availability: {xtype: 'xcheckbox',  description: '<b>[[+availability]]</b><br />'+_('ms2_product_availability_help'),inputValue: 1,checked: parseInt(config.record.availability || 1)}
		}
	}
	,getColumns: function() {
		return {
			availability: {width:50, sortable:true, editor: {xtype:'combo-boolean', renderer:'boolean'}}
		}
	}
};

if (isset($this->modx->map[$class])) {
                        foreach ($map as $key => $values) {
                            $this->modx->map[$class][$key] = array_merge($this->modx->map[$class][$key], $values);
                        }
                    }