Как в Yii2 после регистрации создать записи в бд?

<?php
/**
 * Created by PhpStorm.
 * User: User
 * Date: 23.04.2018
 * Time: 19:31
 */

namespace app\models;


use Yii;
use yii\base\Model;

class Signup extends Model
{public $username;
 public $email;
 public $password;
 public function rules()
 {
     return[
       [['email','username','password'],'required'],
         ['email', 'email'],
         ['password','string','min'=>2,'max'=>30]
     ];
 }
 public function signup()
 {
     $developer=new Developers();
     $developer->username=$this->username;
     $developer->email=$this->email;
     $developer->password=Yii::$app->getSecurity()->generatePasswordHash($this->password);
     return $developer->save();


 }
}

$model = new Product;
        $model->category_id='2';
        $model->author_id=$app->user->identity['id'];
        $model->name='name';
        $model->content='content';
        $model->price='0';
        $model->keywords='NULL';
        $model->description='NULL';
        $model->hit='0';
        $model->new='0';
        $model->save();