Accessing magento's checkout/cart using REST API - api

Question

I'm trying to integrate a cart-synchronisation-solution for my rest-clients.
The goal should be that I can have the same cart wherever I access my store from.
So I'll have to first of all deliver the existing items out to the client using the authenticated api-user.
But I get stuck at the very beginning:
protected function _retrieveCollection()
{
$cart = Mage::getSingleton('checkout/cart')->getQuote();
$cart->setCustomerId($this->getApiUser()->getUserId());
$cart->setStoreId(4);
$cart->load();
return $cart->getAllItems();
}
returns an empty array even though I have products in my cart.
Anyone any hints? Have that feeling I'm totally on the wrong side...

Answer 1

Found a solution. Getting the quote by Customer which is the other way around worked pretty well:
Mage::app()->setCurrentStore(4);
$cart = Mage::getModel('sales/quote')->loadByCustomer($this->getApiUser()->getUserId());
$items = array();
foreach ($cart->getAllVisibleItems() as $key => $item) {
$items[] = array(
'name' => $item->getName(),
'entity_id' => $item->getProductId(),
'description' => $item->getDescription(),
'final_price_with_tax' => $item->getBasePriceInclTax(),
'qty' => $item->getQty()
);
}