course-site/app/Http/Resources/UserCollection.php

<?php

/*
 * This file is part of the Jiannei/lumen-api-starter.
 *
 * (c) Jiannei <longjian.huang@foxmail.com>
 *
 * This source file is subject to the MIT license that is bundled
 * with this source code in the file LICENSE.
 */

namespace App\Http\Resources;

use Illuminate\Http\Resources\Json\ResourceCollection;

class UserCollection extends ResourceCollection
{
    public function toArray($request)
    {
        return $this->collection->map(function ($item) {
            return [
                'nickname' => $item->name,
                'email' => $item->email,
            ];
        })->all();
    }
}