Proof of Concept: An approach to Fat models, skinny controllers with Event Dispatcher in Symfony

OurAbstractController.php

<?php declare(strict_types=1);

namespace App\Controller;

use Symfony\Bundle\FrameworkBundle\Controller\AbstractController;
use Symfony\Component\Validator\ConstraintViolationListInterface;
use Symfony\Component\HttpFoundation\Request;
use App\Event\RepositoryEvent;

/**
 * Class OurAbstractController
 * @package App\Controller
 */
abstract class OurAbstractController extends AbstractController
{
    /**
     * Get entity name for CRUD
     * @return string
     */
    abstract public function getEntityName();

    /**
     * Get entity service manager
     * @return mixed
     */
    abstract protected function getServiceManager();

    /**
     *  Standard logic for creating resource
     * @param Request $request
     * @param object $entity
     * @param array $validationGroups
     * @return $entity | ConstraintViolationListInterface
     */
    public function createResource(Request $request, $entity, array $validationGroups = [])
    {
        $event = new RepositoryEvent($entity, 'create');
        $this->get('event_dispatcher')->dispatch('okApp.pre_validate', $event);

        $errors = $this->validate($entity, $validationGroups);
        if (count($errors) > 0) {
            return $errors; // TODO: use error validation formatter instead!
        }

        // TODO: add permissions check
        $this->getDoctrine()->getManager()->persist($entity);
        $this->get('event_dispatcher')->dispatch('okApp.pre_flush', $event);
        $this->getDoctrine()->getManager()->flush(); // save changes to already attached entity
        $this->get('event_dispatcher')->dispatch('okApp.post_flush', $event);

        return $entity;
    }
    /**
     * Standard logic for updating resource
     *
     * @param Request $request
     * @param $entity
     * @param array $validationGroups
     * @return mixed
     */
    public function updateResource(Request $request, $entity, array $validationGroups = [])
    {
        $event = new RepositoryEvent($entity, 'update');
        $this->get('event_dispatcher')->dispatch('okApp.pre_validate', $event);

        $errors = $this->validate($entity, $validationGroups);
        if (count($errors) > 0) {
            return $errors; // TODO: use error validation formatter instead!
        }

        $this->getDoctrine()->getManager()->persist($entity);
        // TODO: add support of request passing as variable to check _opt status, add $context to $event for more custom handling
        $this->get('event_dispatcher')->dispatch('okApp.pre_flush', $event);

        // TODO: add validation, permissions check
        $this->getDoctrine()->getManager()->flush(); // save changes to already attached entity

        $this->get('event_dispatcher')->dispatch('okApp.post_flush', $event);
        return $entity;
    }
    /**
     * Standard logic for deletion resource
     *
     * @param $entity
     * @return mixed
     */
    public function deleteResource($entity)
    {
        $this->getDoctrine()->getManager()->remove($entity);
        $event = new RepositoryEvent($entity, 'delete');
        $this->get('event_dispatcher')->dispatch('okApp.pre_validate', $event);
        $this->get('event_dispatcher')->dispatch('okApp.pre_flush', $event);
        $this->getDoctrine()->getManager()->flush(); // save changes to already attached entity
        $this->get('event_dispatcher')->dispatch('okApp.post_flush', $event);

        return $entity;
    }
  
    /**
     * @param $entity
     * @param array $groups
     * @return ConstraintViolationListInterface
     */
    protected function validate($entity, $groups = null)
    {
        // $groups - empty array must be replaced with NULL. Otherwise none of the validation groups will be checked
        return $this->get('validator')->validate($entity, empty($groups) ? null : $groups);
    }
}

PostListener.php

<?php declare(strict_types=1);

namespace App\EventListener;

use App\Event\RepositoryEvent;
use App\Entity\Post;

/**
 * Class PostListener
 * @package App\EventListener
 */
class PostListener
{
    /**
     * @var RepositoryEvent
     */
    protected $event;

    /**
     * @var \Psr\Log\LoggerInterface
     */
    private $logger;

    /**
     * BadWordListener constructor.
     * @param \Psr\Log\LoggerInterface $logger
     */
    public function __construct(\Psr\Log\LoggerInterface $logger)
    {
        $this->logger = $logger;
    }

    /**
     * @param RepositoryEvent $event
     */
    public function preValidate(RepositoryEvent $event)
    {
        if (!$event->getData() instanceof Post
            || $event->getAction() !== 'create'
        ) {
            return ;
        }
        $this->logger->debug('Post Listner preValidate');
        $this->event = $event;
    }

    /**
     * @param RepositoryEvent $event
     */
    public function onPreFlush(RepositoryEvent $event)
    {
        if (!$event->getData() instanceof Post
            || $event->getAction() !== 'create'
        ) {
            return ;
        }
        $this->logger->debug('Post Listner onPostFlush');
        $this->event = $event;
    }

    /**
     * @param RepositoryEvent $event
     */
    public function onPostFlush(RepositoryEvent $event)
    {
        if (!$event->getData() instanceof Post
            || $event->getAction() !== 'create'
        ) {
            return ;
        }
        $this->logger->debug('Post Listner onPostFlush');
        $this->event = $event;
    }
}

RepositoryEvent.php

<?php declare(strict_types=1);

namespace App\Event;

use Symfony\Contracts\EventDispatcher\Event;

/**
 * Class RepositoryEvent
 * @package App\Event
 */
class RepositoryEvent extends Event
{
    /**
     * Collection of entities or single entity
     * @var
     */
    protected $data;
    /**
     * @var null
     */
    protected $action;

    /**
     * RepositoryEvent constructor.
     * @param object $data
     * @param null $action
     */
    function __construct($data, $action = null)
    {
        $this->data = $data;
        $this->action = $action;
    }

    /**
     * @return mixed
     */
    public function getData()
    {
        return $this->data;
    }
    /**
     * @param mixed $data
     */
    public function setData($data)
    {
        $this->data = $data;
    }

    /**
     * @return null
     */
    public function getAction()
    {
        return $this->action;
    }
    /**
     * @param null $action
     */
    public function setAction($action)
    {
        $this->action = $action;
    }
}

services.yaml

    app.event_listener.bad_word:
      class: App\EventListener\PostListener
      autowire: false
      tags:
        - { name: kernel.event_listener, event: okApp.pre_validate, method: preValidate }
        - { name: kernel.event_listener, event: okApp.pre_flush, method: onPreFlush }
        - { name: kernel.event_listener, event: okApp.post_flush, method: onPostFlush }
      arguments: ['@logger']