Overriding \Magento\Quote\Model\ShippingMethodManagement not successful

Question

I've created a module to override

di.xml

<?xml version="1.0"?>
<config xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:noNamespaceSchemaLocation="urn:magento:framework:ObjectManager/etc/config.xsd">
   <preference for="Magento\Quote\Model\ShippingMethodManagement" type="Custom\FixShippingMethod\Model\ShippingMethodManagement"/>
</config>

class:

namespace Custom\FixShippingMethod\Model;

    class ShippingMethodManagement extends \Magento\Quote\Model\ShippingMethodManagement
    {
        /**
         * Get list of available shipping methods
         *
         * @param \Magento\Quote\Model\Quote $quote
         * @param \Magento\Framework\Api\ExtensibleDataInterface $address
         * @return \Magento\Quote\Api\Data\ShippingMethodInterface[]
         */
        public function getShippingMethods(Quote $quote, $address)
        {

            $writer = new \Zend\Log\Writer\Stream(BP . '/var/log/shippingmethodmanagement.log');
            $logger = new \Zend\Log\Logger();
            $logger->addWriter($writer);
            $logger->info('test test test');

            $output = [];
            $shippingAddress = $quote->getShippingAddress();
            //Patch for Magento issue #26682
            /** @see https://github.com/magento/magento2/issues/26682 */
            $addressData = $this->extractAddressData($address);
            if (array_key_exists('extension_attributes', $addressData)) {
                unset($addressData['extension_attributes']);
            }
            $shippingAddress->addData($addressData);
            //End patch
            $shippingAddress->setCollectShippingRates(true);

            $this->totalsCollector->collectAddressTotals($quote, $shippingAddress);
            $shippingRates = $shippingAddress->getGroupedAllShippingRates();
            foreach ($shippingRates as $carrierRates) {
                foreach ($carrierRates as $rate) {
                    $output[] = $this->converter->modelToDataObject($rate, $quote->getQuoteCurrencyCode());
                }
            }
            return $output;
        }

The method didn't run, anyone know what is the problem?

Answer 1

I think you try to override private methode from Magento\Quote\Model\ShippingMethodManagement

private function getShippingMethods(Quote $quote, $address)

you can't overriding private method with magento 2, it's non-public methods, you can refer to here for the documentation https://devdocs.magento.com/guides/v2.3/extension-dev-guide/plugins.html

You can get solution from here Magento 2 Override Private method