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Laravel Queue Job Reads Stale Data in Transaction: Fix

Jobs dispatched in a transaction re-query the DB via SerializesModels before commit, reading stale data. Use afterCommit() to delay dispatch until after commit.

When dispatching a Job to a Queue inside a Transaction, the Job reads stale data.

Why the Job Gets Old Data

Transaction and Queue Job timing race condition

Setup: Laravel connected to a real database, Queue Driver using Redis, one User already in the database, php artisan queue:work running.

In the following code, the Job is delayed by 3 seconds, but the Transaction doesn’t commit until 5 seconds later:

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// tests/Feature/ExampleTest.php
namespace Tests\Feature;

use App\Jobs\EmailChanged;
use App\Models\User;
use Illuminate\Support\Facades\DB;
use Tests\TestCase;

class ExampleTest extends TestCase
{
    public function test_dispatch_user_email_changed(): void
    {
        DB::transaction(static function () {
            $user = User::findOrFail(1);
            $oldEmail = $user->email;
            $newEmail = 'test'.random_int(1, 100).'@gmail.com';
            $user->fill(['email' => $newEmail])->save();
            EmailChanged::dispatch($user, $oldEmail, $newEmail)
                ->delay(now()->addSeconds(3));
            sleep(5);
        });
    }
}

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// app/Jobs/EmailChanged.php
namespace App\Jobs;

use App\Models\User;
use Illuminate\Bus\Queueable;
use Illuminate\Contracts\Queue\ShouldQueue;
use Illuminate\Foundation\Bus\Dispatchable;
use Illuminate\Queue\InteractsWithQueue;
use Illuminate\Queue\SerializesModels;

class EmailChanged implements ShouldQueue
{
    use Dispatchable, InteractsWithQueue, Queueable, SerializesModels;
    private User $user;
    private string $oldEmail;
    private string $newEmail;
    public function __construct(User $user, string $oldEmail, string $newEmail)
    {
        $this->user = $user;
        $this->oldEmail = $oldEmail;
        $this->newEmail = $newEmail;
    }
    public function handle(): void
    {
        dump('old email: '.$this->oldEmail);
        dump('new email: '.$this->newEmail);
        dump('current email:'.$this->user->email);
    }
}

After running, current email still shows the old email. Because SerializesModels only stores the Model ID, the Job re-fetches the data from the database when it runs. But at that point the Transaction hasn’t committed yet, so it reads the old value.

Add afterCommit

Just add afterCommit() when dispatching. Laravel will wait until the Transaction commits before actually pushing the Job to the Queue:

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EmailChanged::dispatch($user, $oldEmail, $newEmail)
    ->delay(now()->addSeconds(3))
    ->afterCommit();

Now the Job reads the correct new data when it runs.