test/app/Http/Models/SiteInfo.php

<?php

namespace App\Http\Models;

use Illuminate\Database\Eloquent\Model;

class SiteInfo extends Model
{
    protected $table = 'sites_info';
    protected $primaryKey = 'site_id';
    public $incrementing = false;
    protected $guarded = [];
    protected $casts = ['keyword' => 'array'];

}