Eccubeで○○円以上送料無料にする処理

app/Customize/Service/PurchaseFlow/Processor/CustomDeliveryFeePreprocessor.php というファイルを下記のように作成します。

CustomDeliveryFeePreprocessor.php

<?php

namespace Customize\Service\PurchaseFlow\Processor;

use Eccube\Service\PurchaseFlow\ItemHolderPreprocessor;
use Eccube\Entity\ItemHolderInterface;
use Eccube\Service\PurchaseFlow\PurchaseContext;
use Eccube\Repository\BaseInfoRepository;
use Eccube\Annotation\ShoppingFlow;

/**
 * Description of CustomDeliveryFeePreprocessor
 *
 * @ShoppingFlow
 */
class CustomDeliveryFeePreprocessor implements ItemHolderPreprocessor {

    /** @var BaseInfo */
    protected $BaseInfo;

    /**
     * DeliveryFeePreprocessor constructor.
     *
     * @param BaseInfoRepository $baseInfoRepository
     */
    public function __construct(
            BaseInfoRepository $baseInfoRepository,
    )
    {
        $this->BaseInfo = $baseInfoRepository->get();
    }

    public function process(ItemHolderInterface $itemHolder, PurchaseContext $context)
    {
        $this->updateDeliveryFeeItem($itemHolder);
    }

    /**
     * @param ItemHolderInterface $itemHolder
     */
    private function updateDeliveryFeeItem(ItemHolderInterface $itemHolder)
    {
        // 10,000円を超える場合は送料無料
        $totalPrice = 0.0;
        foreach ($Shipping->getOrderItems() as $item) {
            if (!$item->isDeliveryFee()) {
                $totalPrice = $totalPrice + $item->getTotalPrice();
            }
        }
        if ( $totalPrice >= 10000 ) {
            foreach ($Shipping->getOrderItems() as $item) {
                if ($item->isDeliveryFee()) {
                    $item->setPrice(0);
                }
            }
        }
    }

}

かんたんですね。