Product id (multisite setup) - php

Question

We are building a script that makes an xml export of orders. In the export, we need to get the EAN code of the product that has been ordered. Currently we use WooCommerce to get the product info, and get the _sku from there.
However, we notice something is going wrong with our multisite setup.
When a product is ordered from site B, we sometimes are unable to get the EAN code of the ordered product, or get a wrong EAN code.
This because if we use our script and ask WooCommerce -> getOrder -> getItems, we get the product id's from site A, not site B. So when we try to get the _sku info from an ordered item, it's looking for the wrong product.
How can we make sure that with our script, it knows what _sku to take when we get our order information so that it doesn't matter which site the order came from, the order information is always correct?
function bol_2020_custom_process_order_manual($order_id) {
global $voorletters;
$order = new WC_Order( $order_id );
// $myuser_id = (int)$order->user_id;
// $user_info = get_userdata($myuser_id);
// $customer = new WC_Customer($order_id);
$items = $order->get_items();
$xml_order_id = $order_id;
$xml_ORDER_DATE = date('Y-m-d');
$xml_DELIVERY_START_DATE = '2017-09-07';
$xml_DELIVERY_END_DATE = '2017-09-08';
$xml_SUPPLIER_NAME = 'DOMAINNAME.nl';
$xml_SUPPLIER_NAME2 = '';
$xml_SUPPLIER_NAME3 = '';
$xml_SUPPLIER_STREET = '**** 71A';
$xml_SUPPLIER_ZIP = '******';
$xml_SUPPLIER_CITY = '********';
$xml_SUPPLIER_COUNTRY = 'NL';
$xml_BUYUR_NAME = get_post_meta($order_id,'_shipping_first_name',true).' '.get_post_meta($order_id,'_shipping_last_name',true);
$xml_BUYUR_NAME2 = get_post_meta($order_id,'_shipping_company',true);
$xml_BUYUR_NAME3 = '';
$xml_BUYUR_STREET = get_post_meta($order_id,'_shipping_address_1',true).' '.get_post_meta($order_id,'_shipping_address_2',true);
$xml_BUYUR_ZIP = get_post_meta($order_id,'_shipping_postcode',true);
$xml_BUYUR_CITY = get_post_meta($order_id,'_shipping_city',true);
$xml_BUYUR_COUNTRY = get_post_meta($order_id,'_shipping_country',true);
$imp = new DOMImplementation;
$dtd = $imp->createDocumentType('ORDER', '', 'openTRANS_ORDER_1_0.dtd');
$dom = $imp->createDocument("", "", $dtd);
$dom->encoding = 'UTF-8';
$root = $dom->appendChild($root = $dom->createElement('ORDER'));
$order_version = $root->appendChild($dom->createAttribute('version'));
$order_version->value = '1.0';
$order_type = $root->appendChild($dom->createAttribute('type'));
$order_type->value = 'standard';
$root->appendChild($client = $dom->createElement('ORDER_HEADER'));
$order_info = $client->appendChild($dom->createElement('ORDER_INFO'));
$order_info->appendChild($ORDER_ID = $order_info->appendChild($dom->createElement('ORDER_ID')));
$ORDER_ID->appendChild($dom->createTextNode($voorletters.$xml_order_id));
$order_info->appendChild($ALT_CUSTOMER_ORDER_ID = $order_info->appendChild($dom->createElement('ALT_CUSTOMER_ORDER_ID')));
$ALT_CUSTOMER_ORDER_ID->appendChild($dom->createTextNode(''));
$order_info->appendChild($ORDER_DATE = $order_info->appendChild($dom->createElement('ORDER_DATE')));
$ORDER_DATE->appendChild($dom->createTextNode($xml_ORDER_DATE));
$DELIVERY_DATE = $order_info->appendChild($order_info->appendChild($dom->createElement('DELIVERY_DATE')));
$DELIVERY_DATE_ATT = $DELIVERY_DATE->appendChild($dom->createAttribute('type'));
$DELIVERY_DATE_ATT->value = 'fixed';
$DELIVERY_START_DATE = $DELIVERY_DATE->appendChild($dom->createElement('DELIVERY_START_DATE'));
$DELIVERY_START_DATE->appendChild($dom->createTextNode($xml_DELIVERY_START_DATE));
$DELIVERY_END_DATE = $DELIVERY_DATE->appendChild($dom->createElement('DELIVERY_END_DATE'));
$DELIVERY_END_DATE->appendChild($dom->createTextNode($xml_DELIVERY_END_DATE));
$ORDER_PARTIES = $order_info->appendChild($order_info->appendChild($dom->createElement('ORDER_PARTIES')));
$BUYER_PARTY = $ORDER_PARTIES->appendChild($dom->createElement('BUYER_PARTY'));
$PARTY_ID = $BUYER_PARTY->appendChild($dom->createElement('PARTY'));
$PARTY_ID_ = $PARTY_ID->appendChild($dom->createElement('PARTY_ID'));
$PARTY_ID__ATT = $PARTY_ID_->appendChild($dom->createAttribute('type'));
$PARTY_ID__ATT->value = 'ILN';
//$PARTY_ID_->appendChild($dom->createTextNode('4317784032988'));
$PARTY_ID_->appendChild($dom->createTextNode('4317784044110'));
$SUPPLIER_PARTY = $ORDER_PARTIES->appendChild($dom->createElement('SUPPLIER_PARTY'));
$PARTY_ID = $SUPPLIER_PARTY->appendChild($dom->createElement('PARTY'));
$PARTY_ID_ = $PARTY_ID->appendChild($dom->createElement('PARTY_ID'));
$PARTY_ID__ATT = $PARTY_ID_->appendChild($dom->createAttribute('type'));
$PARTY_ID__ATT->value = 'ILN';
$PARTY_ID_->appendChild($dom->createTextNode('4317784000000'));
$SHIPMENT_PARTIES = $ORDER_PARTIES->appendChild($dom->createElement('SHIPMENT_PARTIES'));
$DELIVERY_PARTY = $SHIPMENT_PARTIES->appendChild($dom->createElement('DELIVERY_PARTY'));
$PARTY = $DELIVERY_PARTY->appendChild($dom->createElement('PARTY'));
$PARTY_ID = $PARTY->appendChild($dom->createElement('PARTY_ID'));
$PARTY_ID_ATT = $PARTY_ID->appendChild($dom->createAttribute('type'));
$PARTY_ID_ATT->value = 'supplier_specific';
$PARTY_ID->appendChild($dom->createTextNode(''));
$ADDRESS = $PARTY->appendChild($dom->createElement('ADDRESS'));
$NAME = $ADDRESS->appendChild($dom->createElement('NAME'));
$NAME->appendChild($dom->createTextNode($xml_SUPPLIER_NAME));
$NAME2 = $ADDRESS->appendChild($dom->createElement('NAME2'));
$NAME2->appendChild($dom->createTextNode($xml_SUPPLIER_NAME2));
$NAME3 = $ADDRESS->appendChild($dom->createElement('NAME3'));
$NAME3->appendChild($dom->createTextNode($xml_SUPPLIER_NAME3));
$STREET = $ADDRESS->appendChild($dom->createElement('STREET'));
$STREET->appendChild($dom->createTextNode($xml_SUPPLIER_STREET));
$ZIP = $ADDRESS->appendChild($dom->createElement('ZIP'));
$ZIP->appendChild($dom->createTextNode($xml_SUPPLIER_ZIP));
$CITY = $ADDRESS->appendChild($dom->createElement('CITY'));
$CITY->appendChild($dom->createTextNode($xml_SUPPLIER_CITY));
$COUNTRY = $ADDRESS->appendChild($dom->createElement('COUNTRY'));
$COUNTRY->appendChild($dom->createTextNode($xml_SUPPLIER_COUNTRY));
$FINAL_DELIVERY_PARTY = $SHIPMENT_PARTIES->appendChild($dom->createElement('FINAL_DELIVERY_PARTY'));
$PARTY = $FINAL_DELIVERY_PARTY->appendChild($dom->createElement('PARTY'));
$PARTY_ID = $PARTY->appendChild($dom->createElement('PARTY_ID'));
$PARTY_ID_ATT = $PARTY_ID->appendChild($dom->createAttribute('type'));
$PARTY_ID_ATT->value = 'buyer_specific';
$PARTY_ID->appendChild($dom->createTextNode(''));
$ADDRESS = $PARTY->appendChild($dom->createElement('ADDRESS'));
$NAME = $ADDRESS->appendChild($dom->createElement('NAME'));
$NAME->appendChild($dom->createTextNode($xml_BUYUR_NAME));
$NAME2 = $ADDRESS->appendChild($dom->createElement('NAME2'));
$NAME2->appendChild($dom->createTextNode($xml_BUYUR_NAME2));
$NAME3 = $ADDRESS->appendChild($dom->createElement('NAME3'));
$NAME3->appendChild($dom->createTextNode($xml_BUYUR_NAME3));
$STREET = $ADDRESS->appendChild($dom->createElement('STREET'));
$STREET->appendChild($dom->createTextNode($xml_BUYUR_STREET));
$ZIP = $ADDRESS->appendChild($dom->createElement('ZIP'));
$ZIP->appendChild($dom->createTextNode($xml_BUYUR_ZIP));
$CITY = $ADDRESS->appendChild($dom->createElement('CITY'));
$CITY->appendChild($dom->createTextNode($xml_BUYUR_CITY));
$COUNTRY = $ADDRESS->appendChild($dom->createElement('COUNTRY'));
$COUNTRY->appendChild($dom->createTextNode($xml_BUYUR_COUNTRY));
$PARTIAL_SHIPMENT_ALLOWED = $order_info->appendChild($order_info->appendChild($dom->createElement('PARTIAL_SHIPMENT_ALLOWED')));
$PARTIAL_SHIPMENT_ALLOWED->appendChild($dom->createTextNode('False'));
$TRANSPORT = $order_info->appendChild($order_info->appendChild($dom->createElement('TRANSPORT')));
$INCOTERM = $TRANSPORT->appendChild($dom->createElement('INCOTERM'));
$INCOTERM->appendChild($dom->createTextNode(''));
$LOCATION = $TRANSPORT->appendChild($dom->createElement('LOCATION'));
$LOCATION->appendChild($dom->createTextNode('EKD'));
$TRANSPORT_REMARK = $TRANSPORT->appendChild($dom->createElement('TRANSPORT_REMARK'));
$TRANSPORT_REMARK->appendChild($dom->createTextNode('10'));
$REMARK_GENERAL = $order_info->appendChild($order_info->appendChild($dom->createElement('REMARK')));
$REMARK_GENERAL_ = $REMARK_GENERAL->appendChild($dom->createAttribute('type'));
$REMARK_GENERAL_->value = 'general';
$REMARK_GENERAL->appendChild($dom->createTextNode('SUPERHANDIG.NL IS HÉT ADRES VOOR PROF. GEREEDSCHAP EN ACCESSOIRES!'));
$REMARK_ORDER = $order_info->appendChild($order_info->appendChild($dom->createElement('REMARK')));
$REMARK_ORDER_ = $REMARK_ORDER->appendChild($dom->createAttribute('type'));
$REMARK_ORDER_->value = 'order';
$REMARK_ORDER->appendChild($dom->createTextNode($voorletters.$xml_order_id));
$ORDER_ITEM_LIST = $root->appendChild($client = $dom->createElement('ORDER_ITEM_LIST'));
$i = 0;
foreach ($items as $item) {
$ean = get_post_meta($item['product_id'], '_sku'); // for single products
$qty = $item['qty'];
if(empty($ean[0])){
$ean = get_post_meta($item['variation_id'], '_sku'); // for variable products
}
$i++;
$ORDER_ITEM = $ORDER_ITEM_LIST->appendChild($dom->createElement('ORDER_ITEM'));
$LINE_ITEM_ID = $ORDER_ITEM->appendChild($dom->createElement('LINE_ITEM_ID'));
$LINE_ITEM_ID->appendChild($dom->createTextNode($i));
$ARTICLE_ID = $ORDER_ITEM->appendChild($dom->createElement('ARTICLE_ID'));
$SUPPLIER_AID = $ARTICLE_ID->appendChild($dom->createElement('SUPPLIER_AID'));
$SUPPLIER_AID->appendChild($dom->createTextNode(''));
$INTERNATIONAL_AID = $ARTICLE_ID->appendChild($dom->createElement('INTERNATIONAL_AID'));
$INTERNATIONAL_AID_ = $INTERNATIONAL_AID->appendChild($dom->createAttribute('type'));
$INTERNATIONAL_AID_->value = 'EAN';
$INTERNATIONAL_AID->appendChild($dom->createTextNode($ean[0]));
$BUYER_AID = $ARTICLE_ID->appendChild($dom->createElement('BUYER_AID'));
$BUYER_AID_ = $BUYER_AID->appendChild($dom->createAttribute('type'));
$BUYER_AID_->value = 'BP';
$BUYER_AID->appendChild($dom->createTextNode(''));
$BUYER_AID = $ARTICLE_ID->appendChild($dom->createElement('BUYER_AID'));
$BUYER_AID_ = $BUYER_AID->appendChild($dom->createAttribute('type'));
$BUYER_AID_->value = 'IN';
$BUYER_AID->appendChild($dom->createTextNode(''));
$DESCRIPTION_SHORT = $ARTICLE_ID->appendChild($dom->createElement('DESCRIPTION_SHORT'));
$DESCRIPTION_SHORT->appendChild($dom->createTextNode(''));
$QUANTITY = $ORDER_ITEM->appendChild($dom->createElement('QUANTITY'));
$QUANTITY->appendChild($dom->createTextNode($qty));
$ORDER_UNIT = $ORDER_ITEM->appendChild($dom->createElement('ORDER_UNIT'));
$ORDER_UNIT->appendChild($dom->createTextNode('C62'));
}
$ORDER_SUMMARY = $root->appendChild($client = $dom->createElement('ORDER_SUMMARY'));
$TOTAL_ITEM_NUM = $ORDER_SUMMARY->appendChild($dom->createElement('TOTAL_ITEM_NUM'));
$TOTAL_ITEM_NUM->appendChild($dom->createTextNode($i));
$dom->formatOutput = true;
$dom->save($_SERVER['DOCUMENT_ROOT'].'/ede_orders/xml/'.$voorletters.$xml_order_id.'.xml');
}
https://gist.github.com/webstylecenter/2491735366a70d82336512e0d0cc4e8f