我写下面的功能为设置默认Woocommerce的变化由最低价格和库存.但问题是这个功能工作正常，当用户请求第二次请求的产品页面！当第一次显示产品，默认的变化不工作的权利！这更新变量产品的默认变化后，第一次请求！

add_action( 'woocommerce_before_variations_form', 'set_default_variation_job' );
function set_default_variation_job() {
   
   
    $product_id = get_the_ID();
    $product    = wc_get_product($product_id); // Get the variable product object

    // Only for variable products & Check if default variation has been updated
    if ( $product->is_type( 'variable' ) ) {

        $active_prices  = $product->get_variation_prices()['price']; // Array of variation Id / active price pairs
            foreach ($active_prices as $key => $value) {
                 $variation = wc_get_product($key);
                if($value == "0" || !$variation->is_in_stock()){
                    unset($active_prices[$key]);
                }
            }
        asort($active_prices, SORT_NUMERIC);    

        $variations_ids = array_keys($active_prices); // Array of variations IDs
        $variation_id   = strval($variations_ids[0]); // Get the variation with the Lowest price
        
        $variation = wc_get_product( $variation_id ); // Get an instance of the WC_Product_Variation object
        $default_attributes = $variation->get_variation_attributes(false); // Get formatted variation attributes         
        update_post_meta($product_id, '_default_attributes', $default_attributes);

         }
}

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错误的Woocommerce默认变体