如何获取通过特定策略的所有用户的列表？

Question

When a project is added, I fetch all users who have the permission to view it to inform them.
This happens in a listener:

use App\Models\User;
use Illuminate\Support\Facades\Gate;

// ...

$notifiables = User::all()->filter(function(User $user) use($event) {
    return Gate::forUser($user)->allows('view', $event->project);
});

This works. But when I've got 1000 users in my system and 5 are able to view the project, I'm iterating over 995 users for nothing.
And as the event and the listener run synchronously, the user adding a project has to wait for this to happen.

How can I accelerate this?

Edit: Okay, it's possible to queue listeners. However, it would be great to improve this code.

Answer 1

I'm not familiar with the Gate Facade but if it's in a model with relations, you can use whereHas :

$users = App\User::whereHas('permissions', function ($q) use ($event) {
    $q->where('name', 'view')->where('model_id', $event->project->id);
})->get();

https://laravel.com/docs/5.7/eloquent-relationships#querying-relationship-existence