File: //proc/thread-self/cwd/wp-content/plugins/automatewoo/includes/Actions/Update_Product_Meta.php
<?php
// phpcs:ignoreFile
namespace AutomateWoo;
if ( ! defined( 'ABSPATH' ) ) exit;
/**
 * @class Action_Update_Product_Meta
 */
class Action_Update_Product_Meta extends Action {
	public $required_data_items = [ 'product' ];
	function load_admin_details() {
		$this->title = __( 'Update Custom Field', 'automatewoo' );
		$this->group = __( 'Product', 'automatewoo' );
	}
	function load_fields() {
		$meta_key = ( new Fields\Text() )
			->set_name( 'meta_key' )
			->set_title( __('Key', 'automatewoo') )
			->set_required()
			->set_variable_validation();
		$meta_value = ( new Fields\Text() )
			->set_name( 'meta_value' )
			->set_title( __( 'Value', 'automatewoo') )
			->set_variable_validation();
		$this->add_field($meta_key);
		$this->add_field($meta_value);
	}
	function run() {
		if ( ! $product = $this->workflow->data_layer()->get_product() ) {
			return;
		}
		$meta_key   = trim( $this->get_option( 'meta_key', true ) );
		$meta_value = $this->get_option( 'meta_value', true );
		// Make sure there is a meta key but a value is not required
		if ( $meta_key ) {
			$product->update_meta_data( $meta_key, $meta_value );
			$product->save();
		}
	}
}