symfony - 使用事件监听器创建 preUpdate 或 preFlush 事件

Question

我有一个 onFlush() 事件，工作正常，但我需要做的是将其转换为 preFlush() 或 preUpdate() 都可以接受。我做了 preFlush() 但由于某种原因它没有做任何事情。甚至没有一个错误。我错过了什么？

测试:我在 preFlush() 中放置了 exit 来查看它是否被调用。结果是:1，因此 foreach() 永远不会运行!它是一个空数组。我还测试了 preUpdate() ，其中的所有行都已运行，但没有插入数据。

public function preFlush(PreFlushEventArgs $args)
{
    $em = $args->getEntityManager();
    $uow = $em->getUnitOfWork();
    echo '1';
    foreach ($uow->getScheduledEntityUpdates() as $entity) {
        echo '2';
        if ($entity instanceof User) {
            echo '3';
        }
    }
    exit;
}

我在阅读 documentation 后创建了它们.

service.yml

services:
    entity.event_listener.user:
        class:  Site\FrontBundle\EventListener\Entity\UserListener
        tags:
            - { name: doctrine.event_listener, event: preUpdate }
            - { name: doctrine.event_listener, event: onFlush }
            - { name: doctrine.event_listener, event: preFlush }

使用 Flush() 示例:

class UserListener
{
    public function onFlush(OnFlushEventArgs $args)
    {
        $em = $args->getEntityManager();
        $uow = $em->getUnitOfWork();

        foreach ($uow->getScheduledEntityUpdates() as $entity) {
            if ($entity instanceof User) {
                $userLog = new UserLog();
                $userLog->setDescription($entity->getId() . ' being updated.');

                $em->persist($userLog);

                // Instead of $em->flush() cos we're already in flush process
                $userLogMetadata = $em->getClassMetadata(get_class($userLog));
                $uow->computeChangeSet($userLogMetadata, $userLog);
            }
        }
    }
}

不工作 preFlush() 示例:

class UserListener
{
    public function preFlush(PreFlushEventArgs $args)
    {
        $em = $args->getEntityManager();
        $uow = $em->getUnitOfWork();

        foreach ($uow->getScheduledEntityUpdates() as $entity) {
            if ($entity instanceof User) {
                $userLog = new UserLog();
                $userLog->setDescription($entity->getId() . ' being updated.');

                $em->persist($userLog);

                // Instead of $em->flush() cos we're already in flush process
                $userLogMetadata = $em->getClassMetadata(get_class($userLog));
                $uow->computeChangeSet($userLogMetadata, $userLog);
            }
        }
    }
}

不工作 preUpdate() 示例

class UserListener
{
    public function preUpdate(LifecycleEventArgs $args)
    {
        $entity = $args->getEntity();
        $em = $args->getEntityManager();
        $uow = $em->getUnitOfWork();

        if ($entity instanceof User) {
            $userLog = new UserLog();
            $userLog->setDescription($entity->getId() . ') been updated.');

            $em = $args->getEntityManager();
            $em->persist($userLog);
            $userLogMetadata = $em->getClassMetadata(get_class($userLog));
            $uow->computeChangeSet($userLogMetadata, $userLog);
        }
    }
}

Answer 1

解决方案:

诀窍是，在 postFlush() 事件中的 preUpdate() 之后持续存在。

注意:虽然这可能不是最好的解决方案，但它回答了问题，但是可以使用事件订阅者或简单的 onFlush() -> 事件监听器中的 $uow->getScheduledEntityUpdates()。

Service.yml

services:

    entity.event_listener.user_update:
        class:  Site\FrontBundle\EventListener\Entity\UserUpdateListener
        tags:
            - { name: doctrine.event_listener, event: preUpdate }
            - { name: doctrine.event_listener, event: postFlush }

事件监听器

<?php

namespace Site\FrontBundle\EventListener\Entity;

use Doctrine\ORM\Event\LifecycleEventArgs;
use Doctrine\ORM\Event\PostFlushEventArgs;
use Site\FrontBundle\Entity\User;
use Site\FrontBundle\Entity\UserLog;

class UserUpdateListener
{
    private $log = array();

    public function preUpdate(LifecycleEventArgs $args)
    {
        $entity = $args->getEntity();

        // False check is compulsory otherwise duplication occurs
        if (($entity instanceof User) === false) {
            $userLog = new UserLog();
            $userLog->setDescription($entity->getId() . ' being updated.');

            $this->log[] = $userLog;
        }
    }

    public function postFlush(PostFlushEventArgs $args)
    {
        if (! empty($this->log)) {
            $em = $args->getEntityManager();
            foreach ($this->log as $log) {
                $em->persist($log);
            }
            $em->flush();
        }
    }
}