Programatically clear the cart of a logged-in user

Question

TL;DR When a customer is logged in, Mage::getSingleton('checkout/session')->clear(); doesn't clear their cart. I need something that will.

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I've asked this as part of another question, but i discovered it was actually two problems, other other one now fixed.

I'm programatically creating an order in a controller using the items in the cart. After the order is saved the cart should be cleared. I do this using

Mage::getSingleton('checkout/session')->clear();

which works fine most of the time. The problem comes when the customer is logged-in. If they are logged in the cart doesn't clear. I've found other solutions (like load the cart items and removed them one at a time in a loop) but they don't meet all my requirements. WHat I need is something that will:

1. remove all the items (obviously)
2. stay on the same page (why loading the cart doesn't seem to work. I end up redirected to the cart page)
3. NOT go to another page and then come back (2 redirects won't work in this case)

Is there something different I need to do when they are logged in? How can I get the cart cleared? Thanks all for the help.

Answer 1

Check quote status is_active for the quote (sales_flat_quote) regarding to the created order. If its active (value is 1) set it inactive ($quote->setIsActive(0)->save()) after successfully order creation and than clear checkout session.

Answer 2

This is against standard Magento logic, so you need a custom module that will observe customer_logout event and execute the following code bit:

foreach( Mage::getSingleton('checkout/session')->getQuote()->getItemsCollection() as $item ){
 Mage::getSingleton('checkout/cart')->removeItem( $item->getId() )->save();
}

more info

Answer 3

/** @var Mage_Sales_Model_Quote $quote */
$quote = Mage::getSingleton('checkout/session')->getQuote();
$quote->removeAllItems()->save();

Answer 4

This should do a job (note that without checking if cart actually has items it will not work good):

$cart = Mage::getSingleton('checkout/cart');
if (count($cart->getItems())) {
    $cart->truncate();
    $cart->save();
}

Answer 5

If you want to clear cart of a specific customer, here is the way

$customerId = 4;
$quote = Mage::getModel('sales/quote')->loadByCustomer($customerId);
$quote->removeAllItems()->save();

Answer 6

For Magento 2.3 Users And Above

For more modern versions of Magento it is now preferred to use Service Contract design patterns over Magento\Checkout\Model\Cart or Magento\Checkout\Helper\Cart therefore I was able to achieve the same functionality using Repositories as well as the Checkout Session manager:

/** @var \Magento\Quote\Model\Quote $cart */
$cart = $this->_checkoutSession
   ->clearQuote()
   ->getQuote()
   ->unsetData('any_custom_quote_attribute')
   ->removeAllItems();

/** @var \Magento\Quote\Api\CartRepositoryInterface $this->_cartRepository */
$this->_cartRepository->save($cart);

/** @var \Magento\Checkout\Model\Session $this->_checkoutSession */
$this->_checkoutSession->replaceQuote($cart);