Transaction issue inside the eloquent observer `saved` event

[lk77]

• Laravel Version: 5.8.29
• Nova Version: 2.0.9
• PHP Version: 7.3.3
• Operating System and Version: Debian 9
• Browser type and version: chrome 75
• Reproduction Repository: https://github.com/lk77/nova-observer-transaction-bug

Description:

Hello,

we have an issue with nova inside eloquent observers saved events,
we expect that any transaction that nova opens, should be closed when the saved observer method is called, which is not the case.

We want to do something in the observer, like a file deletion, an http request or an event broadcast, something that can be undone. And the fact that transaction is still open and that the row doesn't exists in database yet is not consistent.

That action in the observer will cause other actions in cascade of third parties, like incoming requests. So a incoming request, that wants to recover a newly created instance, will get an error, because row doesn't exist yet (transaction is still going). It depends on the latency between the server and the client, but it's not quite right.

Steps To Reproduce:

1 / git clone https://github.com/lk77/nova-observer-transaction-bug
2 / composer update
3 / cp .env.example .env // change database informations
4 / php artisan serve
5 / go to http://localhost:8000/nova/resources/tests
6 / click on the create button
7 / open F12 network on chrome (or whatever you are using)
8 / submit a new test
9 / inside http://localhost:8000/nova-api/tests request, see the dump saying :

"transation status : open"

the code responsible for the dump inside App\Observers\TestObserver::saved :

dd('transation status : ' . (\DB::transactionLevel() > 0 ? 'open' : 'closed'));

10 / see in database the test row has not been added.

For now, the solution seems to add this inside resource :

    /**
     * Return the location to redirect the user after creation.
     *
     * @param \Laravel\Nova\Http\Requests\NovaRequest $request
     * @param \App\Nova\Resource $resource
     * @return string
     */
    public static function redirectAfterCreate(NovaRequest $request, $resource)
    {
        // do custom process here, after transaction

        return parent::redirectAfterCreate($request,  $resource);
    }

wich is more like a hack.

A possible solution will be to introduce a hook inside resource, called after transaction in controller.

thanks.

[meyer59]

We have the same problem here.
Wen we reach the saved Observer method, the model is not actually saved in the db.
How we could lunch an action after the transaction commit ?

[bonzai]

Can you install fntneves/laravel-transactional-events to see if it fixes your issue?

[lk77]

It does not fix my issue,
this package is for custom events,
not the eloquent events, and is not working with observers.

[bonzai]

@lk77: It's working fine for me. Are you sure you are using this package correctly? If you are using observers, you have to update the config because it will ignore all the Eloquent events.

Also, for the record, this issue isn't related to Nova, but Laravel - laravel/framework#8627.

[lk77]

yes, i have commented all the lines in the exclude array, and the transaction is still open inside the saved method of the observer.

I need to add eloquent.saved to the transactional array aswell for this to work

We resolved this, by moving our code inside the redirectAfterCreate and redirectAfterUpdate methods inside resource and it is working fine. We do not want to rely on a third party package, it's messing a lot with our tests, and having to override dispatcher does not seems to be a good solution.

[mfn]

Hello everyone,

based on an existing package and with permission of its original author, I've drafted a possible solution to tackle the "transactional events" problem.

At the moment it's a draft PR in my Laravel forked repo to first gather feedback from the community before approaching to create an official PR, to give things time to unfold / develop.

I invite everyone to participate in mfn/laravel-framework#1 and share your feedback.

Thank you!