Magento2: How to reserve product after add to the basket

Question

I want to set in our website reserve product after add to the basket.

example:

Shoes available in stock: 5 pcs.

When customer add 2 pcs to the basket then now in website is available 3 pcs.

After 24 hours when customer no finalize trasaction then delete product from basket and return this 2 pcs to stock.

Any solution?

Answer 1

I have the solution for you but there are some major issues with decreasing stock when you add the product to cart. If a customer adds maximum products cart, then someone next can't add more because it is out of stock. So please make sure you understand what you are doing.

- Create an event to the observer when a product is added to cart

1. app/code/Training/Test/etc/frontend/events.xml

<?xml version="1.0"?>
<config xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:noNamespaceSchemaLocation="urn:magento:framework:Event/etc/events.xsd">
    <event name="sales_quote_product_add_after">
        <observer name="training_test_inventory" instance="Training\Test\Observer\DecreaseStockObserver"/>
    </event>
</config>

2. app/code/Training/Test/Observer/DecreaseStockObserver.php

<?php

namespace Training\Test\Observer;

use Magento\Framework\Event\ObserverInterface;
use Magento\CatalogInventory\Api\StockManagementInterface;
use Magento\Framework\Event\Observer;
use Magento\CatalogInventory\Observer\ItemsForReindex;
use Magento\CatalogInventory\Observer\ProductQty;

class DecreaseStockObserver implements ObserverInterface
{

    /**
     * @var StockManagementInterface
     */
    private $stockManagement;

    /**
     * @var ItemsForReindex
     */
    private $itemsForReindex;
    /**
     * @var ProductQty
     */
    private $productQty;

    /**
     * SubtractQuoteInventoryObserver constructor.
     * @param StockManagementInterface $stockManagement
     * @param ProductQty $productQty
     * @param ItemsForReindex $itemsForReindex
     */
    public function __construct(
        StockManagementInterface $stockManagement,
        ProductQty $productQty,
        ItemsForReindex $itemsForReindex
    ) {
        $this->stockManagement = $stockManagement;
        $this->productQty = $productQty;
        $this->itemsForReindex = $itemsForReindex;
    }

    /**
     * @param Observer $observer
     * @return void
     */
    public function execute(Observer $observer)
    {
        $event = $observer->getEvent();
        $items = $this->productQty->getProductQty($event->getItems());
        $itemsForReindex = $this->stockManagement->registerProductsSale(
            $items
        );
        $this->itemsForReindex->setItems($itemsForReindex);
    }
}

• Create a cronjob to delete carts and revert qty to stock:

3. app/code/Training/Test/etc/crontab.xml

<config xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
        xsi:noNamespaceSchemaLocation="urn:magento:module:Magento_Cron:etc/crontab.xsd">
    <group id="default">
        <job name="training_flush_quotes" instance="Training\Test\Cron\FlushQuotes"
             method="execute">
            <schedule>0 * * * *</schedule>
        </job>
    </group>
</config>

4. app/code/Training/Test/Cron/FlushQuotes.php

<?php

namespace Training\Test\Cron;

use Magento\Quote\Api\CartRepositoryInterface;
use Magento\CatalogInventory\Api\StockManagementInterface;
use Magento\CatalogInventory\Observer\ProductQty;
use Magento\Framework\Api\SearchCriteriaBuilder;

class FlushQuotes
{
    private $cartRepository;
    /**
     * @var StockManagementInterface
     */
    private $stockManagement;
    /**
     * @var SearchCriteriaBuilder
     */
    private $searchCriteriaBuilder;
    /**
     * @var ProductQty
     */
    private $productQty;
    /**
     * @var \Magento\CatalogInventory\Model\Indexer\Stock\Processor
     */
    protected $stockIndexerProcessor;

    /**
     * @var \Magento\Catalog\Model\Indexer\Product\Price\Processor
     */
    protected $priceIndexer;

    /**
     * PreviewQuotaManager constructor.
     * @param CartRepositoryInterface $cartRepository
     * @param StockManagementInterface $stockManagement
     * @param ProductQty $productQty
     * @param SearchCriteriaBuilder $searchCriteriaBuilder
     * @param \Magento\CatalogInventory\Model\Indexer\Stock\Processor $stockIndexerProcessor
     * @param \Magento\Catalog\Model\Indexer\Product\Price\Processor $priceIndexer
     */
    public function __construct(
        CartRepositoryInterface $cartRepository,
        StockManagementInterface $stockManagement,
        ProductQty $productQty,
        SearchCriteriaBuilder $searchCriteriaBuilder,
        \Magento\CatalogInventory\Model\Indexer\Stock\Processor $stockIndexerProcessor,
        \Magento\Catalog\Model\Indexer\Product\Price\Processor $priceIndexer
    ) {
        $this->cartRepository = $cartRepository;
        $this->stockManagement = $stockManagement;
        $this->searchCriteriaBuilder = $searchCriteriaBuilder;
        $this->productQty = $productQty;
        $this->stockIndexerProcessor = $stockIndexerProcessor;
        $this->priceIndexer = $priceIndexer;
    }

    /**
     * @return void
     * @throws \Exception
     */
    public function execute()
    {
        $carts = $this->cartRepository->getList($this->searchCriteriaBuilder->create())
            ->getItems();
        foreach ($carts as $cart) {
            /** @var \Magento\Quote\Api\Data\CartInterface $cart */
            $this->revertProductsSales($cart);
            $this->cartRepository->delete($cart);
        }

    }

    /**
     * @param $cart
     */
    private function revertProductsSales(\Magento\Quote\Api\Data\CartInterface $cart)
    {
        $items = $cart->getAllItems();
        $itemsToUpdate = $this->productQty->getProductQty($items);
        $this->stockManagement->revertProductsSale(
            $itemsToUpdate
        );
        if (!empty($itemsToUpdate)) {
            $updatedItemIds = array_keys($itemsToUpdate);
            $this->stockIndexerProcessor->reindexList($updatedItemIds);
            $this->priceIndexer->reindexList($updatedItemIds);
        }
    }
}

Try this solution, maybe it will solve your issue

Regards

Answer 2

For all those who land here from google, it looks like it is better to use the Magento Reservations API now, which is part of Magento Multi-Stock-Inventory module, see this: https://devdocs.magento.com/guides/v2.3/inventory/reservations.html

You would probably bind to the same events as @bachlee89 showed in his solution, but instead of decreasing quantity in stock - you create a reservation and then reset/clean up it on a cron-job for abandoned carts.