Update custom meta data for Orders in Woocommerce - php

Question

I'm trying to update the Woocommerce Orders with a custom meta data field
On Woocommerce order complete (status change) I have a Invoicing plugin that automatically generates customer invoice documents, this plugin has its own hooks/filters such as:
apply_filters('moloni_after_insert_document', $this);
After it inserts (generates) the invoice, I use their API to return a value ( the invoice code ) that I want to save on that order meta data.
This is the code that I use:
add_action('moloni_after_insert_document', 'save_codigo_at', 10, 4 );
function save_codigo_at( $order_id ) {
// On Order complete > access Moloni API > GETPDFLINK > Sanitize string and get Hash > Get document ID from order >
// Retrieve from the Database table moloni_api the access token from column main_token
global $wpdb;
$table_name = "wp_moloni_api";
$retrieve_data = $wpdb->get_results( "SELECT * FROM $table_name WHERE id = 1" );
foreach ($retrieve_data as $retrieved_data) {
$maintoken = $retrieved_data->main_token;
}
// Get document ID from the order
$documentid = get_post_meta($order->id, '_moloni_sent', true);
// Connect to moloni API and getpdflink
$url = "https://api.moloni.pt/v1/documents/getOne/?access_token=$maintoken";
$postData = array(
'company_id' => '11111',
'document_id' => $documentid );
$arguments = array(
'method' => 'POST',
'headers' => array(
'Content-type: application/x-www-form-urlencoded'
),
'body' => $postData,
);
$response = wp_remote_post( $url, $arguments );
if ( is_wp_error( $response ) ) {
$error_message = $response->get_error_message();
return "Something went wrong: $error_message";
} else {
echo '<pre>';
var_dump( wp_remote_retrieve_body( $response ) );
echo '</pre>';
// jsondecode the string received by the API to remove weird backslashes, get and parse the URL and extract the HASH key
$response2 = wp_remote_retrieve_body($response);
parse_str(parse_url(json_decode($response2, true)['url'], PHP_URL_QUERY), $result);
$hash = $result['h'];
//CONVERT JSON array to PHP array
$response3 = json_decode($response2);
$invoicecode = $response3->transport_code; //GET INVOICE CODE from the PHP ARRAY
echo $invoicecode;
$order = wc_get_order( $order_id );
$order->update_meta_data( '_codigo_at', $invoicecode );
$order->save();
}
}
Now I am successfully able to get the code from their response.
However I can't save it because I always get the following PHP fatal error:
PHP Fatal error: Uncaught Error: Call to a member function update_meta_data() on bool in
From what I understood so far, this would likely be because $order is not defined as an object on this filter moloni_after_insert_document
Because when I try just to save a test random meta value but instead using a filter like woocommerce_order_status_completed then $order seems to work for updating meta data, the problem is that I must only run this action after the moloni_after_insert_document filter, because it is only then that the Invoice Code is generated and available
How could I properly define the $order inside of this code?
I am not sure how to handle/proceed in this situation
Thank you in advance for the attention and advice

Answer 1

It is necessary to add
global $woocommerce, $post;
to the code, as adding this global has fixed the problem because it allowed to define the $order object.
I don't know if this is the most efficient way of doing so, but it has managed to make the code work.