Syncing Many to many relationship in Event Listener (Laravel 5.7)

Question

Laravel App has roles and each Role has permissions (many to many)

Each user has multiple roles (Many to many)

When the permissions of Role are changed/updated, Event RolePermissionsChanged is triggered and the listener has following code:

public function handle(RolePermissionsChanged $event)
{
     $role_permissions=$event->role()->permissions;
     foreach ($event->role()->users as $user) {
        $user->permissions()->sync($role_permissions);
      }
}

This has to update permission_user table to sync the roles to the user. When the event is triggered, the job fails with an error:

Method Illuminate\Database\Eloquent\Collection::sync does not exist.

If I change the line in foreach loop to App\User::find($user->id)->permissions()->sync($role_permissions);, it is working but I know it should be done the other way. Can anyone guide where I am going wrong.

Edit:

Below is RolePermissionsChanged::class

<?php

namespace App\Events\Auth;

use Illuminate\Queue\SerializesModels;
use Illuminate\Foundation\Events\Dispatchable;
use App\Role;

class RolePermissionsChanged
{
    use Dispatchable, SerializesModels;

    public $role;

    public function __construct(Role $role)
    {
        $this->role=$role;
    }

}

Can you add the code for your `RolePermissionsChanged` class to your question? — Rwd, Jan 06 '19 at 08:46
Where is `$event->role()` coming from as I don't see a `role()` method in your `RolePermissionsChanged` class? — Rwd, Jan 06 '19 at 09:00
I think the issue is `$event->role()` will return a Collection instance whereas `foreach ($event->role->users as $user)` this should work. — Mozammil, Jan 06 '19 at 09:12
It is being passed as an instance of `App\Role:class` as described in Laravel Documentation. https://laravel.com/docs/5.7/events#defining-listeners — Curated Prime, Jan 06 '19 at 09:14

score 1 · Accepted Answer · answered Jan 06 '19 at 10:05

1

$event->role() should be $event->role, it's a public property defined in the event class, where $event->role() is treating it as a function call.

public function handle(RolePermissionsChanged $event)
{
    $permission_ids = $event->role->permissions->pluck('id')->toArray();

    $event->role->users->each(function (User $user) use ($permission_ids) {
        $user->permissions()->sync($permission_ids);
    });
}

answered Jan 06 '19 at 10:05

Brian Lee

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I deleted my answer. I think this should be accepted. just with a change: `$user->permissions->sync($permission_ids);` – Iqlas Uddin Jan 06 '19 at 10:26
1

thanks, yes this works with the edit. :) thanks both – Curated Prime Jan 06 '19 at 10:28

Syncing Many to many relationship in Event Listener (Laravel 5.7)

1 Answers1