Mrthdrb

I want to add a free product to cart with another product. For that I wrote checkout_cart_product_add_after event observer. My problem is, I don't get the updated cart subtotal(after adding first product, it returns subtotal as 0). This is my observer code.

namespace StwBuyXGetYBuyXGetYObserver;
use MagentoFrameworkEventObserverInterface;
use MagentoFrameworkAppRequestInterface;
use MagentoFrameworkRegistry;

class AddfreeProduct implements ObserverInterface

 protected $_productRepository;
 protected $_cart;
 protected $formKey;
 public function __construct(
 MagentoCheckoutModelCart $cart, 
 PsrLogLoggerInterface $logger,
 MagentoFrameworkDataFormFormKey $formKey)
 $this->cart = $cart;
 $this->formKey = $formKey;
 $this->logger = $logger;
 
 public function execute(MagentoFrameworkEventObserver $observer)
 
 $totals = $this->cart->getQuote()->getTotals();
 $subtotal = $totals['subtotal']->getValue(); 
 $this->logger->debug($subtotal);
 

Any help will be greatly appreciated.

We should use MagentoCheckoutModelSession:

/**
 * @var MagentoCheckoutModelSession
 */
protected $_checkoutSession;

public function __construct(
 MagentoCheckoutModelSession $checkoutSession,
 .....
)

 $this->_checkoutSession = $checkoutSession;

Try to get the totals:

//Get totals
$this->_checkoutSession->getQuote()->getTotals();
//Get sub total.
$this->_checkoutSession->getQuote()->getSubtotal();

You can try

$this->_cartTotalRepository using MagentoQuoteModelCartCartTotalRepository

$totals = $this->_cartTotalRepository->get($this->cart->getQuote()->getId());
// Subtotal
$subtotal = (float) $totals->getSubtotal();

Let me know if you have any question.