exchange-2.0/app/Http/Resources/KeyValueBasicResource.php

<?php

namespace App\Http\Resources;

use Carbon\Carbon;
use Illuminate\Http\Resources\Json\JsonResource;

class KeyValueBasicResource extends JsonResource
{
    /**
     * Transform the resource into an array.
     *
     * @param  \Illuminate\Http\Request $request
     * @return array
     */
    public function toArray($request)
    {
        return [
            // 'id' => $this->id,
            'key' => $this->key,
            'value' => $this->value,
            'year' => Carbon::parse($this->created_at)->format('Y'),
        ];
    }
}