WC_Product_Data_Store_CPT::update_post_meta PHP Method

    protected function update_post_meta(&$product)
    {
        $updated_props = array();
        $changed_props = array_keys($product->get_changes());
        $meta_key_to_props = array('_visibility' => 'catalog_visibility', '_sku' => 'sku', '_regular_price' => 'regular_price', '_sale_price' => 'sale_price', '_sale_price_dates_from' => 'date_on_sale_from', '_sale_price_dates_to' => 'date_on_sale_to', 'total_sales' => 'total_sales', '_tax_status' => 'tax_status', '_tax_class' => 'tax_class', '_manage_stock' => 'manage_stock', '_backorders' => 'backorders', '_sold_individually' => 'sold_individually', '_weight' => 'weight', '_length' => 'length', '_width' => 'width', '_height' => 'height', '_upsell_ids' => 'upsell_ids', '_crosssell_ids' => 'cross_sell_ids', '_purchase_note' => 'purchase_note', '_default_attributes' => 'default_attributes', '_virtual' => 'virtual', '_downloadable' => 'downloadable', '_product_image_gallery' => 'gallery_image_ids', '_download_limit' => 'download_limit', '_download_expiry' => 'download_expiry', '_featured' => 'featured', '_thumbnail_id' => 'image_id', '_stock' => 'stock_quantity', '_stock_status' => 'stock_status', '_wc_average_rating' => 'average_rating', '_wc_rating_count' => 'rating_counts', '_wc_review_count' => 'review_count');
        foreach ($meta_key_to_props as $meta_key => $prop) {
            if (!in_array($prop, $changed_props)) {
                continue;
            }
            $value = $product->{"get_{$prop}"}('edit');
            switch ($prop) {
                case 'virtual':
                case 'downloadable':
                case 'manage_stock':
                case 'featured':
                case 'sold_individually':
                    $updated = update_post_meta($product->get_id(), $meta_key, wc_bool_to_string($value));
                    break;
                case 'gallery_image_ids':
                    $updated = update_post_meta($product->get_id(), $meta_key, implode(',', $value));
                    break;
                case 'image_id':
                    if (!empty($value)) {
                        set_post_thumbnail($product->get_id(), $value);
                    } else {
                        delete_post_meta($product->get_id(), '_thumbnail_id');
                    }
                    $updated = true;
                    break;
                default:
                    $updated = update_post_meta($product->get_id(), $meta_key, $value);
                    break;
            }
            if ($updated) {
                $updated_props[] = $prop;
            }
        }
        if (in_array('date_on_sale_from', $updated_props) || in_array('date_on_sale_to', $updated_props) || in_array('regular_price', $updated_props) || in_array('sale_price', $updated_props)) {
            if ($product->is_on_sale()) {
                update_post_meta($product->get_id(), '_price', $product->get_sale_price());
                $product->set_price($product->get_sale_price());
            } else {
                update_post_meta($product->get_id(), '_price', $product->get_regular_price());
                $product->set_price($product->get_regular_price());
            }
        }
        if (in_array('featured', $updated_props)) {
            delete_transient('wc_featured_products');
        }
        if (in_array('catalog_visibility', $updated_props)) {
            do_action('woocommerce_product_set_visibility', $product->get_id(), $product->get_catalog_visibility());
        }
        if (in_array('stock_quantity', $updated_props)) {
            do_action($product->is_type('variation') ? 'woocommerce_variation_set_stock' : 'woocommerce_product_set_stock', $product);
        }
        if (in_array('stock_status', $updated_props)) {
            do_action($product->is_type('variation') ? 'woocommerce_variation_set_stock_status' : 'woocommerce_product_set_stock_status', $product->get_id(), $product->get_stock_status(), $product);
        }
        // Update extra data associated with the product.
        // Like button text or product URL for external products.
        if (!$this->extra_data_saved) {
            foreach ($product->get_extra_data_keys() as $key) {
                $function = 'get_' . $key;
                if (in_array($key, $changed_props) && is_callable(array($product, $function))) {
                    update_post_meta($product->get_id(), '_' . $key, $product->{$function}('edit'));
                }
            }
        }
    }

 /**
  * Helper method that updates all the post meta for a grouped product.
  *
  * @param WC_Product
  * @param bool $force Force all props to be written even if not changed. This is used during creation.
  * @since 2.7.0
  */
 protected function update_post_meta(&$product, $force = false)
 {
     if (update_post_meta($product->get_id(), '_children', $product->get_children('edit'))) {
         $child_prices = array();
         foreach ($product->get_children('edit') as $child_id) {
             $child = wc_get_product($child_id);
             if ($child) {
                 $child_prices[] = $child->get_price();
             }
         }
         $child_prices = array_filter($child_prices);
         delete_post_meta($product->get_id(), '_price');
         if (!empty($child_prices)) {
             add_post_meta($product->get_id(), '_price', min($child_prices));
             add_post_meta($product->get_id(), '_price', max($child_prices));
         }
         $this->extra_data_saved = true;
     }
     parent::update_post_meta($product, $force);
 }