related-products-macros.php

<?php

add_filter( 'jet-theme-core/listings/macros-list', 'jet_register_custom_macros' );

/**
 * Add new macros to default macros list
 *
 * %jet_related_products% - macros name
 *
 */
function jet_register_custom_macros( $macros_list ) {
	$macros_list['jet_related_products'] = 'jet_related_products';
	return $macros_list;
}

/**
 * Macros callback function
 */
function jet_related_products() {
	
	$result   = array();
	$products = get_post_meta( get_the_ID(), 'related-products-list', true );

	if ( ! $products ) {
		return '';
	}

	foreach ($products as $product) {
		if ( ! empty( $product['product_id'] ) ) {
			$result[] = $product['product_id'];
		}
		
	}

	return implode( ',', $result );

}