Доктрина Symfony: отношение «один ко многим» удаляет родительский объект

У меня есть родительский и дочерний объект. После того, как все дочерние сущности будут удалены, symfony также удалит мою родительскую сущность. Мне не нравится такое поведение, родительский объект должен существовать независимо от того, есть ли дочерние элементы или нет. Вот мой код для родителя:

    /**
     * @OneToMany(targetEntity="Gallery", mappedBy="promotion", cascade={"persist", "remove"})
     */
    private $galleries;

    public function __construct() {
        $this->galleries = new ArrayCollection();
    }

    public function getGalleries() {
        return $this->galleries;
    }

    public function addGallery($gallery)
    {
        $gallery->setPromotion($this);
        $this->galleries[] = $gallery;

        return $this;
    }

    public function removeGallery($gallery)
    {
        $gallery->setPromotion(null);
        $this->galleries->removeElement($gallery);
    }

А вот для ребенка:

    /**
     * @ManyToOne(targetEntity="Promotion", inversedBy="galleries")
     */

    private $promotion;

Я не знаю, что делать, я уже потратил часы на это.

Это обрабатывается простым пакетом администратора, поэтому он вам не поможет:

namespace AppBundle\Controller;

use JavierEguiluz\Bundle\EasyAdminBundle\Event\EasyAdminEvents;
use Symfony\Component\Security\Acl\Exception\Exception;
use AppBundle\Entity\Promotion;
use Symfony\Component\HttpFoundation\JsonResponse;

class PromotionController extends PageController {
    protected $folder = 'promotions';
    protected $htmlFileName = 'default-template.html';

    protected function rearangeAction() {
        $ids = json_decode($this->request->get('ids'));
        $order = 1;

        foreach($ids as $id) {            
            $this->em->createQuery('UPDATE AppBundle:Promotion p SET p.order = :order WHERE p.id = :id')
                ->setParameter('order', $order++)
                ->setParameter('id', $id)
                ->execute();
        }

        return $this->redirectToRoute('easyadmin', $this->prepareRouteParams());
    }

    protected function checkFolderAction() {        
        $row = $this->em->createQuery('SELECT p FROM AppBundle:Promotion p WHERE p.language = :language AND p.subfolder = :subfolder')
                ->setParameter('language', $this->language)
                ->setParameter('subfolder', $this->request->get('subfolder'))
                ->getOneOrNullResult();

        if($row) {
            return new JsonResponse(array('duplicity' => 1));
        } else {
            return new JsonResponse(array('duplicity' => 0));
        }
    }

    protected function deleteFiles($databaseSubFolders) {
        $mainFolder = $this->baseDir.'/'.$this->folder.'/'.$this->language;

        $databaseSubFolders[] = '..';
        $databaseSubFolders[] = '.';

        $subFolders = array_diff(scandir($mainFolder), $databaseSubFolders);

        foreach($subFolders as $subFolder) {
            $this->deleteFolder($mainFolder.'/'.$subFolder);
        }
    }

    protected function exportAction() {
        $query = $this->em->createQuery('SELECT p FROM AppBundle:Promotion p WHERE p.language = :language')
                ->setParameter('language', $this->language);

        $subFolders = array();

        foreach($query->getArrayResult() as $key => $val) {
            $subFolders[] = $val['subfolder'];

            //  pridanie novych a uprava starych

            $image = basename($val['headerImage']);
            $imageName = substr($image, 0 ,strpos($image,'.'));

            $all = '<div class="header">
                        <div class="row">
                            <h2>
                                '.$val['headerTitle'].'
                            </h2>
                            <p>
                                '.$val['headerTeaser'].'
                            </p>
                        </div>
                    </div><img src="{{::promo.imgPath}}/'.$image.'" alt="'.$imageName.'">';

            $all .= $this->changeMarkdownToHtml($val['html']);
            $all .= $this->changeMarkdownToHtml($val['terms']);

            file_put_contents($this->baseDir.'/'.$this->folder.'/'.$this->language.'/'.$val['subfolder'].'/html/'.$val['filename'], $all);
        }

        //  zmazanie starych zloziek

        $this->deleteFiles($subFolders);        

        parent::exportAction();

        return $this->redirectToRoute('easyadmin', $this->prepareRouteParams());
    }

    private function actualImage($id, $i) {
        $row = $this->em->createQuery('SELECT p FROM AppBundle:Promotion p WHERE p.id = :id')
                ->setParameter('id', $id)
                ->getOneOrNullResult();

        return call_user_func_array(array($row,'getImage'.$i), array());
    }

    protected function preDeleteEntity($id) {
        //  mazanie obrazkov


    }

    protected function preSearchEntity($entity) {
        $entity['search']['dql_filter'] = "entity.language = '".$this->language."'";

        return $entity;
    }

    protected function prePersistEntity($entity) {
        //  ukladanie dalsich dat

        $entity->setLanguage($this->language);
        $entity->setFilename($this->htmlFileName);

        $row = $this->em->createQuery('SELECT MAX(p.order)+1 FROM AppBundle:Promotion p')
                ->getOneOrNullResult();

        $entity->setOrder($row[1]);

        return $entity;
    }

    protected function postPersistEntity($entity) {
        if(!is_dir($this->baseDir.'/'.$this->folder.'/'.$this->language.'/'.$entity->getSubfolder())) {                
            mkdir($this->baseDir.'/'.$this->folder.'/'.$this->language.'/'.$entity->getSubfolder());
            mkdir($this->baseDir.'/'.$this->folder.'/'.$this->language.'/'.$entity->getSubfolder().'/'.'header');
            mkdir($this->baseDir.'/'.$this->folder.'/'.$this->language.'/'.$entity->getSubfolder().'/'.'html');
            mkdir($this->baseDir.'/'.$this->folder.'/'.$this->language.'/'.$entity->getSubfolder().'/'.'img');
        }

        //  presun obrazkov

        $images = array();

        foreach($entity->getGalleries()->getSnapshot() as $snapshot) {
            $image = $snapshot->getImage();

            $from = $this->get('kernel')->getRootDir().'/../web/uploads/temp/'.basename($image);
            $to = $this->baseDir.'/'.$this->folder.'/'.$this->language.'/'.$entity->getSubfolder().'/img/'.$image;

            $this->copyFile($from, $to);

            $images[] = $image;
        }

        $getImage = $entity->getHeaderImage();

        $from = $this->get('kernel')->getRootDir().'/../web/uploads/temp/'.basename($getImage);
        $to = $this->baseDir.'/'.$this->folder.'/'.$this->language.$getImage;

        $this->copyFile($from, $to);

        $entity->setHtml($this->replaceImages($entity->getHtml(), $images));

        return $entity;
    }

    protected function preRemoveEntity($entity) {
        //if($_POST['_method'] != 'DELETE') {
//            var_dump($entity);
//            die();
        //}

        return $entity;
    }

    protected function editAction() {    
        $id = $this->request->query->get('id');

        $this->dispatch(EasyAdminEvents::PRE_EDIT);
        $this->executeDynamicMethod('preEdit<EntityName>Entity', array($id));

        $easyadmin = $this->request->attributes->get('easyadmin');
        $entity = $easyadmin['item'];        

        if ($this->request->isXmlHttpRequest() && $property = $this->request->query->get('property')) {
            $newValue = 'true' === mb_strtolower($this->request->query->get('newValue'));
            $fieldsMetadata = $this->entity['list']['fields'];

            if (!isset($fieldsMetadata[$property]) || 'toggle' !== $fieldsMetadata[$property]['dataType']) {
                throw new \RuntimeException(sprintf('The type of the "%s" property is not "toggle".', $property));
            }

            $this->updateEntityProperty($entity, $property, $newValue);

            return new Response((string) $newValue);
        }

        $fields = $this->entity['edit']['fields'];

        $editForm = $this->executeDynamicMethod('create<EntityName>EditForm', array($entity, $fields));

        $deleteForm = $this->createDeleteForm($this->entity['name'], $id);

        //  kontrola pre presun

        $row = $this->em->createQuery('SELECT p FROM AppBundle:Promotion p WHERE p.id = :id')
                    ->setParameter('id', $id)
                    ->getOneOrNullResult();

        $previousSubfolder = $row->getSubfolder();

        $editForm->handleRequest($this->request);

        if ($editForm->isSubmitted() && $editForm->isValid()) {
            $this->dispatch(EasyAdminEvents::PRE_UPDATE, array('entity' => $entity));            
            $entity = $this->executeDynamicMethod('preUpdate2<EntityName>Entity', array($entity,$previousSubfolder));

            $this->em->flush();

            $this->dispatch(EasyAdminEvents::POST_UPDATE, array('entity' => $entity));            
            $entity = $this->executeDynamicMethod('postUpdate2<EntityName>Entity', array($entity,$previousSubfolder));

            $refererUrl = $this->request->query->get('referer', '');           

            return !empty($refererUrl)
                ? $this->redirect(urldecode($refererUrl))
                : $this->redirect($this->generateUrl('easyadmin', array('action' => 'list', 'entity' => $this->entity['name'])));
        }

        $this->dispatch(EasyAdminEvents::POST_EDIT);        
        $entity = $this->executeDynamicMethod('postEdit<EntityName>Entity', array($entity));

        return $this->render($this->entity['templates']['edit'], array(
            'form' => $editForm->createView(),
            'entity_fields' => $fields,
            'entity' => $entity,
            'delete_form' => $deleteForm->createView(),
        ));
    }

    protected function preUpdate2Entity($entity, $previousSubfolder) {


//        if($_POST['delete_form']['_easyadmin_delete_flag'] == 1) {
//            $this->em->createQuery('DELETE FROM AppBundle:Gallery g WHERE g.promotion = :id')
//                    ->setParameter('id', $id)
//                    ->execute();
//        }


        $images = array();        

        foreach($entity->getGalleries()->getSnapshot() as $snapshot) {
            $image = $snapshot->getImage();

            $images[] = $image;
        }



        $entity->setHtml($this->replaceImages($entity->getHtml(), $images));

        return $entity;
    }

    protected function postUpdate2Entity($entity, $previousSubfolder) {
        if(!is_dir($this->baseDir.'/'.$this->folder.'/'.$this->language.'/'.$entity->getSubfolder())) {                
            mkdir($this->baseDir.'/'.$this->folder.'/'.$this->language.'/'.$entity->getSubfolder());
            mkdir($this->baseDir.'/'.$this->folder.'/'.$this->language.'/'.$entity->getSubfolder().'/'.'header');
            mkdir($this->baseDir.'/'.$this->folder.'/'.$this->language.'/'.$entity->getSubfolder().'/'.'html');
            mkdir($this->baseDir.'/'.$this->folder.'/'.$this->language.'/'.$entity->getSubfolder().'/'.'img');
        }

        //  presun obrazkov

        $images = array();

        foreach($entity->getGalleries()->getSnapshot() as $snapshot) {
            $image = $snapshot->getImage();

            $from = $this->get('kernel')->getRootDir().'/../web/uploads/temp/'.basename($image);
            $to = $this->baseDir.'/'.$this->folder.'/'.$this->language.'/'.$entity->getSubfolder().'/img/'.$image;

            if(!file_exists($from)) {                  
                $from = $this->baseDir.'/'.$this->folder.'/'.$this->language.'/'.$previousSubfolder.'/img/'.$image;
            }

            $this->copyFile($from, $to);
            $images[] = $image;
        }

        //  zmazanie obrazkov

        $folderImages = array_diff(scandir($this->baseDir.'/'.$this->folder.'/'.$this->language.'/'.$previousSubfolder.'/img/'), array('..', '.'));

        foreach($folderImages as $folderImage) {
            if(!in_array($folderImage, $images)) {
                unlink($this->baseDir.'/'.$this->folder.'/'.$this->language.'/'.$previousSubfolder.'/img/'.$folderImage);
            }
        }

        $getImage = $entity->getHeaderImage();

        $from = $this->get('kernel')->getRootDir().'/../web/uploads/temp/'.basename($getImage);

        if(!file_exists($from)) {
            $from = $this->baseDir.'/'.$this->folder.'/'.$this->language.$getImage;
        }

        $to = $this->baseDir.'/'.$this->folder.'/'.$this->language.'/'.$entity->getSubfolder().'/header/'.basename($getImage);

        $this->copyFile($from, $to);

        return $entity;
    }

    protected function postEditEntity($entity) {
        //  cesta pre obrazky        

        $entity->setHeaderImage(null, '/uploads/'.$this->container->getParameter('repo.folder').'/'.$this->folder.'/'.$this->language.$entity->getHeaderImage());

        return $entity;
    }

    protected function preListEntity($entity) {
        $entity['list']['dql_filter'] = "entity.language = '".$this->language."'";

        return $entity;
    }

    protected function postListEntity($fields) {
        //  cesta pre obrazky        

        $fields['headerImage']['base_path'] = '/uploads/'.$this->container->getParameter('repo.folder').'/'.$this->folder.'/'.$this->language;

        return $fields;
    }

    protected function postSearchEntity($fields) {
        //  cesta pre obrazky

        $fields['headerImage']['base_path'] = '/uploads/'.$this->container->getParameter('repo.folder').'/'.$this->folder.'/'.$this->language;

        return $fields;
    }
}