README

Doctrine safe post* events

Doctrine's postPersist, postUpdate and postRemove events are fired when the corresponding SQL queries (INSERT / UPDATE / DELETE) have been performed against the database server.

What happens under the hood is that Doctrine creates a wrapping transaction, runs SQL queries, then commits the transaction.

However, these events are fired immediately, e.g. not once the transaction is complete, which means:

If the wrapping transaction fails, events have already been fired anyway (meaning you trusted generated primary key values, although they're going to be rolled back)
If the wrapping transaction takes some time (typically during row locks), you get the inserted / updated / deleted information before it's actually done (meaning if you run some async process once those events are triggered, you end up in processing not data which is not up-to-date)

Background

The idea of this repository indeed came up with the following issue:

An entity is persisted, then $em->flush() is called
A postPersist event listener gets the entity's id, then asks a worker to do some async processing through Symfony Messenger
The worker queries database against the entity's id, and gets an EntityNotFound exception (the COMMIT did not happen yet)
The flush operation on the main thread completes, and the postFlush event is fired (but it does not contain the inserted / updated / deleted entities)

Our solution

If you run into the same kind of issues, you can replace your listeners' listened events in favor of:

Bentools\DoctrineSafeEvents\SafeEvents::POST_PERSIST (and implement safePostPersist as a replacement of postPersist)
Bentools\DoctrineSafeEvents\SafeEvents::POST_UPDATE (and implement safePostUpdate as a replacement of postUpdate)
Bentools\DoctrineSafeEvents\SafeEvents::POST_REMOVE (and implement safePostRemove as a replacement of postRemove)

Basically, this library will collect entities which are scheduled for insertion / update / deletion, except it will delay event firing until the postFlush occurs.

Installation

composer require bentools/doctrine-safe-events

Usage in Symfony

Although this library has no dependency on Symfony, you can easily use it in your Symfony project:

Bentools\DoctrineSafeEvents\SafeEventsDispatcher:
    tags:
        - { name: 'doctrine.event_subscriber' }
        - { name: 'kernel.reset', method: 'reset' }

Example usage

declare(strict_types=1);

namespace App;

use Bentools\DoctrineSafeEvents\SafeEvents;
use Doctrine\Bundle\DoctrineBundle\Attribute\AsDoctrineListener;
use Doctrine\Persistence\Event\LifecycleEventArgs;

#[AsDoctrineListener(SafeEvents::POST_PERSIST)]
final class SomeListener
{
    public function safePostPersist(LifecycleEventArgs $eventArgs): void
    {
        // ...
    }
}

Tests

composer test

License

MIT.

bentools / doctrine-safe-events

Maintainers

Details