我无法从其他域添加到购物车
我已经启用了CORS标头，ajax工作正常，但随后对cart状态的ajax查询会导致空响应
我想这一定与Cookie/session有关，但不确定是什么（我还没有深入了解WC的内部结构，这几天我的脑袋一直在转，所以我很感谢专家的建议）

这就是我在PHP中的内容：

add_action( \'wp_ajax_a3_add_to_cart\', \'a3_add_to_cart\' );
add_action( \'wp_ajax_nopriv_a3_add_to_cart\', \'a3_add_to_cart\' );

function a3_add_to_cart(){
    header(\'Content-Type: application/json\');

    $product_id = $_REQUEST[\'product_id\'];
    $variation_id = $_REQUEST[\'variation_id\'];
    $quantity = $_REQUEST[\'quantity\'];
    $variation = $_REQUEST[\'variation\'];    

    try{
        WC()->cart->add_to_cart($product_id, $quantity, $variation_id, $variation);
        do_action( \'woocommerce_set_cart_cookies\', TRUE );
        do_action( \'woocommerce_ajax_added_to_cart\', $product_id );
        $context = a3_get_cart_data();
        exit(json_encode(array(\'status\' => \'ok\', \'message\'=> \'Added product to cart\', \'data\' => $context )));
    }    
    catch(Exception $exc){
        exit(json_encode(array(\'status\' => \'error\', \'message\'=> $exc->message)));
    }
}

add_action( \'wp_ajax_a3_get_cart\', \'a3_get_cart\' );
add_action( \'wp_ajax_nopriv_a3_get_cart\', \'a3_get_cart\' );

function a3_get_cart(){    
    header(\'Content-Type: application/json\');

    $context = a3_get_cart_data();

    exit(json_encode($context));
}

function a3_get_cart_data(){
    $cart_items = [];

    WC()->cart->calculate_totals();

    foreach ( WC()->cart->get_cart() as $cart_item_key => $cart_item ) {
        $item = [];

        $_product   = apply_filters( \'woocommerce_cart_item_product\', $cart_item[\'data\'], $cart_item, $cart_item_key );
        $product_id = apply_filters( \'woocommerce_cart_item_product_id\', $cart_item[\'product_id\'], $cart_item, $cart_item_key );

        //var_dump($cart_item[\'data\']);

        if ( $_product && $_product->exists() && $cart_item[\'quantity\'] > 0 && apply_filters( \'woocommerce_cart_item_visible\', true, $cart_item, $cart_item_key ) ) {
            $item[\'product_permalink\'] = apply_filters( \'woocommerce_cart_item_permalink\', $_product->is_visible() ? $_product->get_permalink( $cart_item ) : \'\', $cart_item, $cart_item_key );
            $item[\'product_classes\'] = "woocommerce-cart-form__cart-item " . esc_attr( apply_filters( \'woocommerce_cart_item_class\', \'cart_item\', $cart_item, $cart_item_key ) );
            $item[\'product_remove_link\'] = apply_filters( \'woocommerce_cart_item_remove_link\', sprintf(
                            \'<a href="%s" class="remove" aria-label="%s" data-product_id="%s" data-product_sku="%s">&times;</a>\',
                            esc_url( WC()->cart->get_remove_url( $cart_item_key ) ),
                            __( \'Remove this item\', \'woocommerce\' ),
                            esc_attr( $product_id ),
                            esc_attr( $_product->get_sku() )
                        ), $cart_item_key );
            $item[\'product_image\'] = new TimberImage($_product->get_image_id());
            $item[\'product_name\'] = apply_filters( \'woocommerce_cart_item_name\', $_product->get_name(), $cart_item, $cart_item_key ) . \'&nbsp;\';
            $item[\'product_sku\'] = $_product->get_sku();
            $item[\'product_stock\'] = $_product->get_stock_quantity() > 0 ? \'In stock\' : \'Out of stock\';
            $item[\'item_data\'] =  WC()->cart->get_item_data( $cart_item );
            $item[\'back_order_notification\'] = "";
            // Backorder notification
            if ( $_product->backorders_require_notification() && $_product->is_on_backorder( $cart_item[\'quantity\'] ) ) {
                $item[\'back_order_notification\'] = \'<p class="backorder_notification">\' . esc_html__( \'Available on backorder\', \'woocommerce\' ) . \'</p>\';
            }

            //var_dump(WC()->cart->get_item_data( $cart_item ));
            //exit();

            $item[\'product_price\'] = apply_filters( \'woocommerce_cart_item_price\', WC()->cart->get_product_price( $_product ), $cart_item, $cart_item_key );

            if ( $_product->is_sold_individually() ) {
                $item[\'product_quantity\'] = sprintf( \'1 <input type="hidden" name="cart[%s][qty]" value="1" />\', $cart_item_key );
            } else {
                $item[\'product_quantity\'] = woocommerce_quantity_input( array(
                    \'input_name\'  => "cart[{$cart_item_key}][qty]",
                    \'input_value\' => $cart_item[\'quantity\'],
                    \'max_value\'   => $_product->backorders_allowed() ? \'\' : $_product->get_stock_quantity(),
                    \'min_value\'   => \'0\',
                ), $_product, false );
            }

            $item[\'product_quantity\'] = apply_filters( \'woocommerce_cart_item_quantity\', $item[\'product_quantity\'], $cart_item_key, $cart_item );

            $item[\'subtotal\'] = apply_filters( \'woocommerce_cart_item_subtotal\', WC()->cart->get_product_subtotal( $_product, $cart_item[\'quantity\'] ), $cart_item, $cart_item_key );

            $cart_items[] = $item;      
        }
    }

    $context[\'cart_items\'] = $cart_items;

    return $context;
}

$( document ).on( \'click\', \'.btn-cart\', function() { 

var site = bio_js.siteSettings;

var prod_id = $(\'[name="product_id"]\').val();//store product id in post id variable
var variation_id = $(\'[name="variation_id"]\').val();//store product id in post id variable
var qty = $(\'#qty1\').val();//store quantity in qty variable
var data = {
    action : \'a3_add_to_cart\', 
    product_id : prod_id,
    variation_id : variation_id,
    quantity : qty,                    
};
var variation = {};

$(\'[data-attribute_name]\').each(function(){
    variation[\'attribute_\' + $(this).data(\'attribute_name\')] = $(this).val();
});

data.variation = variation;

$.ajax({
    url : site.ajax_url, 
    type : \'post\', 
    data : data ,
    success : function(resp){                                
        console.log(resp);

        $.post(\'/cart\', {cart:resp.data}, function(resp){
            console.log(resp);
            $.get(site.ajax_url, {action:\'a3_get_cart\'}, function(resp1){
            console.log(resp1);
            });
        });
    }

});

return false;
});