Pony.fm/app/ResourceUser.php

<?php

use Illuminate\Database\Eloquent\Model;

class ResourceUser extends Model
{
    protected $table = 'resource_users';
    public $timestamps = false;

    public static function get($userId, $resourceType, $resourceId)
    {
        $resourceIdColumn = $resourceType . '_id';
        $existing = self::where($resourceIdColumn, '=', $resourceId)->where('user_id', '=', $userId)->first();
        if ($existing) {
            return $existing;
        }

        $item = new ResourceUser();
        $item->{$resourceIdColumn} = $resourceId;
        $item->user_id = $userId;

        return $item;
    }

    public static function getId($userId, $resourceType, $resourceId)
    {
        $item = self::get($userId, $resourceType, $resourceId);
        if ($item->exists) {
            return $item->id;
        }

        $item->save();

        return $item->id;
    }
}