cssd-back/app/Media.php

<?php

namespace App;

use Illuminate\Database\Eloquent\Model;

class Media extends Model
{

    protected $fillable = ['model_id', 'model_type', 'user_id', 'batch_id', 'path', 'file_name', 'file_type'];
    public $timestamps = true;

    public function user()
    {
        return $this->belongsTo('App\User');
    }
    public function model()
    {
        return $this->morphTo();
    }

}