How is the selected shipping method's rate calculated?

dmitry_fedyuk · April 30, 2018, 7:27am

It is done by the Magento\Quote\Model\Quote\Address\Total\Shipping::collect() method:

magento/magento2/blob/2.2.3/app/code/Magento/Quote/Model/Quote/Address/Total/Shipping.php#L164-L182


if ($method) {
    foreach ($address->getAllShippingRates() as $rate) {
        if ($rate->getCode() == $method) {
            $store = $quote->getStore();
            $amountPrice = $this->priceCurrency->convert(
                $rate->getPrice(),
                $store
            );
            $total->setTotalAmount($this->getCode(), $amountPrice);
            $total->setBaseTotalAmount($this->getCode(), $rate->getPrice());
            $shippingDescription = $rate->getCarrierTitle() . ' - ' . $rate->getMethodTitle();
            $address->setShippingDescription(trim($shippingDescription, ' -'));
            $total->setBaseShippingAmount($rate->getPrice());
            $total->setShippingAmount($amountPrice);
            $total->setShippingDescription($address->getShippingDescription());
            break;
        }
    }
}