Queueable listeners randomly start to fail (and don&#39;t end up in the failed_jobs table)

Level 122

In what kind of circumstance would Laravel not be able to catch/handle the exception thrown by or within a job?

If your job tries to find the related model for itself.

For instance, if you pass a model into the constructor of the job, when it is queued then only the ID of the model is queued. When the job is retrieved to be executed, the model referenced is hydrated. It is here that the missing models are handled.

However, if you pass in a model ID (just as plain int) and then do in your handle method, Model::find($this->model_id) then the query will fail and result in an unhandled exception if the model no longer exists.

Level 2

@Snapey thanks for your help.

We noticed that some of the failed jobs, are not all listeners. So also some 'normal jobs' dispatched from the code have the same problem. An example of such a job:

namespace App\Jobs;

use App\Mail\NewDeviceLoginEmail; use App\User; use App\UserLogin; use Illuminate\Bus\Queueable; use Illuminate\Contracts\Queue\ShouldQueue; use Illuminate\Foundation\Bus\Dispatchable; use Illuminate\Queue\InteractsWithQueue; use Illuminate\Queue\SerializesModels; use Mail;

class NewDeviceLogin implements ShouldQueue { use Dispatchable, InteractsWithQueue, Queueable, SerializesModels;

protected UserLogin $userLogin;
protected User $user;

public function __construct(UserLogin $userLogin, User $user)
{
    $this->userLogin = $userLogin;
    $this->user = $user;
}

public function handle(): void
{
    if (!empty($this->user->email)) {
        $this->userLogin->getDeviceLocation();
        Mail::send(new NewDeviceLoginEmail($this->userLogin, $this->user));
    }
}

}

A missing model should be handled by Laravel, but that didn't happen in this case. This job is being dispatched here:

    $userLogin->save();

    if ($isNewDeviceLogin) {
        dispatch(new NewDeviceLogin($userLogin, $user));
    }

The user model is not modified or created in that function. Only the userLogin. You can see that it's being saved before we dispatch the NewDeviceLogin job.

Level 2

@Snapey do you have an idea where this particular message is coming from?

Unhandled exception within Laravel Queue job

Level 122

@nicktenc what makes you think its missing model? Which of these UserLogin or User might be missing?

Level 2

@Snapey in my opinion they can't be missing. Not as in 'the record does not exists'. The user was created months before that event. And the user login model was also created and saved. We didn't wrap it around a transaction. But still the job throws a:

Unhandled exception within Laravel Queue job: 'Illuminate\Database\Eloquent\ModelNotFoundException'

So the exception is a ModelNotFoundException, but from what I can see there are more reasons that trigger this exception?

Level 122

@nicktenc You could have unhandled exception if, for instance, your Mail call failed. Try wrapping the whole thing in try-catch and seeing what error you get.

public function handle(): void
{
	try {
        if (!empty($this->user->email)) {
            $this->userLogin->getDeviceLocation();
            Mail::send(new NewDeviceLoginEmail($this->userLogin, $this->user));
        }
    } catch (\Throwable $th) {
            Log::error('Error in  queued job:' . $th->getMessage());
    }
}

Level 2

@Snapey thanks, but normally Laravel handles failed jobs, and puts them in a failed_jobs table. Wouldn't that prevent that from happening when I manually start catching these exceptions on production?

Level 122

@nicktenc im not suggesting this is a solution, just a temporary diagnostic

Level 2

@Snapey for now we have added the Queue::failing, to do some additional logging on there. But if the exception is unhandled, that won't probably work. Will see if we can wrap some unimportant (but randomly failing jobs) around a try / catch block. Thanks!