Laravel Eloquent exclude specific result from belongsToMany() query

Question

On the User.php model I have the following relationship:

public function roles()
{
    return $this->belongsToMany(Role::class);
}

In the database, I have different roles and basically I want to return all the roles, except the "superadmin" role so that it cannot be displayed in the views or wherever I will choose to show the roles.

I've tried something like:

public function roles()
{
    return $this->belongsToMany(Role::class)->where('name', '!=', 'superadmin');
}

... but it doesn't work. I assume it has something to do with the pivot table. I also tried this:

public function roles()
{
    return $this->belongsToMany(Role::class)->where('role_id, '!=', $id);
}

Any idea how to do this or if it's even possible?

Thanks!

score 2 · Accepted Answer · answered Nov 08 '18 at 21:42

You should try using a Scope on the Roles model.

You could create a Scope called DisplayRole which basically returns all Roles that do not include superadmin and are ok to display to the user. It would look something like this:

namespace App;

use Illuminate\Database\Eloquent\Model;

class DisplayRole extends Role
{
    public function newQuery($excludeDeleted = true)
    {
        return parent::newQuery($excludeDeleted)->where('name','!=','superadmin');
    }
}

Then you can just use DisplayRole the same way you would normally use a model (use App\DisplayRole) and any place that you need to only show the user-friendly roles, use that model instead of the base Role model. That way, calling DisplayRole::all() will return all roles that are not superadmin.

Thanks for the idea! I had like huge hole in my brain and I totally forgot about Scopes. I came up with this scope called scopeExclude() directly on the Role model. Like this: `public function scopeExclude($query, $role) { return $query->where('name', '!=', $role); }` Then I will call it like this wherever I want: `Role::exclude('superadmin')->get();` — Daniel R., Nov 08 '18 at 21:56

score 2 · Answer 2 · answered Nov 08 '18 at 22:08

For anyone interested, here's how I solved this. Thanks to the user eResourcesInc for the idea. However, I choose to make it a little bit simple, so I added the scope directly on the Role.php model, instead of creating a separate php file and and use it. Like so:

public function scopeExclude($query, $role)
{
    return $query->where('name', '!=', $role);
}

Then, whenever I need to get the roles I can now exclude whatever role I want and just get the others, like this:

$roles = Role::exclude('superadmin')->get();

Once again, many thanks for the idea!

Laravel Eloquent exclude specific result from belongsToMany() query

2 Answers2