Plugin.php

<?php

namespace TestPlugin;

use KskCrowdfunding\Components\AccessEnforcer;
use Shopware\Components\CacheManager;
use Shopware\Components\Model\ModelManager;
use Shopware\Components\Plugin;

class TestPlugin extends Plugin
{
    /**
     * @return \Symfony\Component\DependencyInjection\ContainerInterface
     * @throws \Doctrine\DBAL\ConnectionException
     * @throws \Doctrine\DBAL\DBALException
     * @throws \Doctrine\ORM\OptimisticLockException
     * @throws \Exception
     */
    private function getContainer()
    {
        /** @var ModelManager $modelManager */
        $modelManager = $this->container->get('models');

        // exit current transaction
        $modelManager->flush();
        $modelManager->getConnection()->commit();

        // set this plugin to active so the new kernel will boot with it
        $modelManager->getConnection()->exec("UPDATE s_core_plugins SET active = 1, installation_date = NOW() WHERE name = '" . $this->getName() . "';");

        // clear the cache so the container will be rebuilt
        /** @var CacheManager $cacheManager */
        $cacheManager = $this->container->get('shopware.cache_manager');
        $cacheManager->clearProxyCache();

        // clone the kernel and reboot it
        $kernel = clone $this->container->get('kernel');
        $ae = new AccessEnforcer();
        $ae->forceWrite($kernel, 'booted', false);
        $kernel->boot();

        // set this plugin to inactive again
        $modelManager->getConnection()->exec("UPDATE s_core_plugins SET active = 0, installation_date = NULL WHERE name = '" . $this->getName() . "';");

        // start a new transaction
        $modelManager->getConnection()->beginTransaction();

        return $kernel->getContainer();
    }
}