Get the order item Id in WooCommerce order items - php

Question

With WooCommerce, I am trying to change the download URLs for order items. Originally I was using the order ID but that only allows one subscription per order. So I need the customer to be able to purchase more than one subscription.
Here is the code I currently have:
if ( !class_exists( 'pl_wcdf_extention' ) ) {
class pl_wcdf_extention {
public function __construct() {
add_filter( 'woocommerce_order_get_downloadable_items', array( $this, 'download_link' ), 10, 2 );
add_filter( 'woocommerce_customer_get_downloadable_products', array( $this, 'download_link' ), 10, 1 );
}
public function download_link( $downloads, $order = null ) {
$download_url_base = 'https://xxxx.com/';
// retrieve Order ID from Download array
$order_id = $downloads [0]['order_id'];
// retrieve Order data
$order = wc_get_order( $order_id );
// retrieve Order Items
$order_item = $order->get_items();
// retrieve first Order Item ID
$order_item_id = $order_item [0][order_item_id];
foreach ( $downloads as $download ) {
$download['download_url'] = $download_url_base . "xxxx-" . $order_item_id . ".svg";
$tag_item = array(
'--native-libs-dir' => '/home/Lib/',
'--type' => 'template0001style1',
'--data'=> $order_item_id,
'--join' => 'horizontal',
'--output-file' => '/home/public_html/xxxx-' . $order_item_id . '.svg'
);
$args = "";
foreach ($tag_item as $k=>$v) {
$args .= " $k " . " $v ";
}
shell_exec("/home/Python-2.7.14/Python-3.6.3/python /home/Lib/generate-code.py $args");
}
return $downloads;
}
}
}
if ( class_exists( 'pl_wcdf_extention' ) ) {
if ( ! defined( 'ABSPATH' ) ) {
exit; // Exit if accessed directly
}
global $wpdb;
define( 'PL_WCDFE_DIR_PATH', plugin_dir_path( __FILE__ ) );
define( 'PL_WCDFE_PLUGIN_FILE', __FILE__ );
new pl_wcdf_extention();
}
Everything works except I am not able to get the order item ID.
Any help would be appreciated.

Answer 1

To retrieve order item id from the WC_Order_Item Object, please use the get_id() method.
So in your script, you should replace this section:
// retrieve first Order Item ID
$order_item_id = $order_item [0][order_item_id];
with this:
// retrieve first Order Item ID
$order_item_id = $order_item[0]->get_id();