Sylius remaining Twig helper. Returns remaining number of product variant.

RemainingAvailabilityChecker.php

<?php


namespace AppBundle\Inventory;


use Sylius\Component\Inventory\Checker\AvailabilityCheckerInterface;
use Sylius\Component\Inventory\Model\StockableInterface;

/**
 * @author Paweł Jędrzejewski <pawel@sylius.org>
 */
final class RemainingAvailabilityChecker implements AvailabilityCheckerInterface {
    /**
     * {@inheritdoc}
     */
    public function isStockAvailable(StockableInterface $stockable)
    {
        return $this->isStockSufficient($stockable, 1);
    }

    /**
     * {@inheritdoc}
     */
    public function isStockSufficient(StockableInterface $stockable, $quantity)
    {
        return !$stockable->isTracked() || $quantity <= ($stockable->getOnHand() - $stockable->getOnHold());
    }

    public function getRemainingNumber(StockableInterface $stockable) {
        return $stockable->getOnHand() - $stockable->getOnHold();
    }
}

RemainingInventoryExtension.php

<?php


namespace AppBundle\Inventory;

use AppBundle\Inventory\RemainingInventoryHelper;

/**
 * @author Paweł Jędrzejewski <pawel@sylius.org>
 */
final class RemainingInventoryExtension extends \Twig_Extension {
    /**
     * @var RemainingInventoryHelper
     */
    private $helper;

    /**
     * @param RemainingInventoryHelper $helper
     */
    public function __construct(RemainingInventoryHelper $helper)
    {
        $this->helper = $helper;
    }

    /**
     * {@inheritdoc}
     */
    public function getFunctions()
    {
        return [
            new \Twig_SimpleFunction('sylius_inventory_is_available', [$this->helper, 'isStockAvailable']),
            new \Twig_SimpleFunction('sylius_inventory_is_sufficient', [$this->helper, 'isStockSufficient']),
            new \Twig_SimpleFunction('sylius_inventory_get_remaining', [$this->helper, 'getItemsRemainingNumber']),
        ];
    }
}

RemainingInventoryHelper.php

<?php


namespace AppBundle\Inventory;

use Sylius\Component\Inventory\Checker\AvailabilityCheckerInterface;
use Sylius\Component\Inventory\Model\StockableInterface;
use Symfony\Component\Templating\Helper\Helper;

/**
 * @author Paweł Jędrzejewski <pawel@sylius.org>
 */
final class RemainingInventoryHelper extends Helper {
    /**
     * @var AvailabilityCheckerInterface
     */
    private $checker;

    /**
     * @param AvailabilityCheckerInterface $checker
     */
    public function __construct(AvailabilityCheckerInterface $checker)
    {
        $this->checker = $checker;
    }

    /**
     * @param StockableInterface $stockable
     *
     * @return bool
     */
    public function isStockAvailable(StockableInterface $stockable)
    {
        return $this->checker->isStockAvailable($stockable);
    }

    /**
     * @param StockableInterface $stockable
     * @param int $quantity
     *
     * @return bool
     */
    public function isStockSufficient(StockableInterface $stockable, $quantity)
    {
        return $this->checker->isStockSufficient($stockable, $quantity);
    }

    /**
     * @param \Sylius\Component\Inventory\Model\StockableInterface $stockable
     * @return int
     */
    public function getItemsRemainingNumber(StockableInterface $stockable) {
        return $this->checker->getRemainingNumber($stockable);
    }

    /**
     * {@inheritdoc}
     */
    public function getName()
    {
        return 'sylius_inventory';
    }
}

services.yml

sylius.availability_checker.remaining:
        class: AppBundle\Inventory\RemainingAvailabilityChecker

    sylius.templating.helper.inventory:
        class: AppBundle\Inventory\RemainingInventoryHelper
        arguments:
            - "@sylius.availability_checker.remaining"
        tags:
            - { name: templating.helper, alias: sylius_inventory }

    sylius.twig.extension.inventory:
        class: AppBundle\Inventory\RemainingInventoryExtension
        public: false
        arguments:
            - "@sylius.templating.helper.inventory"
        tags:
            - { name: twig.extension }

show.html.twig

{% if sylius_inventory_get_remaining(item.productVariant) < 10 %}
    <div class='attention'>{{ sylius_inventory_get_remaining(item.productVariant) }} pieces left, hurry up!</div>
{% endif %}