Question

I find examples and tutorials about models and about validation. And I places that say the validation (or most of it at least) should be in the model, which I agree with. But I can’t any examples or tutorials that show how that should be done.

Could anyone help me with a simple example on how that could be done? Where would you have the rules in the model? Where would the validation happen? How would the controller know if the validation passed or fail? How would the controller get error messages and things like that?

Hope someone can help, cause feel a bit lost here :p

Answer 1

I too had difficulty finding examples for Kohana3, bestattendance’s example is for Kohana2.

Here’s an example I threw together in my own testing:

application / classes / model / news.php

<?php defined('SYSPATH') OR die('No Direct Script Access');

Class Model_News extends Model
{
    /*
       CREATE TABLE `news_example` (
       `id` INT PRIMARY KEY AUTO_INCREMENT,
       `title` VARCHAR(30) NOT NULL,
       `post` TEXT NOT NULL);
     */

    public function get_latest_news() {
        $sql = 'SELECT * FROM `news_example` ORDER BY `id` DESC LIMIT  0, 10';
        return $this->_db->query(Database::SELECT, $sql, FALSE)
                         ->as_array();
    }

    public function validate_news($arr) {
        return Validate::factory($arr)
            ->filter(TRUE, 'trim')
            ->rule('title', 'not_empty')
            ->rule('post', 'not_empty');
    }
    public function add_news($d) {
        // Create a new user record in the database
        $insert_id = DB::insert('news_example', array('title','post'))
            ->values(array($d['title'],$d['post']))
            ->execute();

        return $insert_id;
    }
}

application / messages / errors.php

<?php
return array(
    'title' => array(
        'not_empty' => 'Title can\'t be blank.',
    ),
    'post' => array(
        'not_empty' => 'Post can\'t be blank.',
    ),
);

application / classes / controller / news.php

<?php defined('SYSPATH') OR die('No Direct Script Access');

Class Controller_News extends Controller
{
    public function action_index() {
        //setup the model and view
        $news = Model::factory('news');
        $view = View::factory('news')
            ->bind('validator', $validator)
            ->bind('errors', $errors)
            ->bind('recent_posts', $recent_posts);

        if (Request::$method == "POST") {
            //added the arr::extract() method here to pull the keys that we want
            //to stop the user from adding their own post data
            $validator = $news->validate_news(arr::extract($_POST,array('title','post')));
            if ($validator->check()) {
                //validation passed, add to the db
                $news->add_news($validator);
                //clearing so it won't populate the form
                $validator = null;
            } else {
                //validation failed, get errors
                $errors = $validator->errors('errors');
            }
        }
        $recent_posts = $news->get_latest_news();
        $this->request->response = $view;
    }
}

application / views / news.php

<?php if ($errors): ?>
<p>Errors:</p>
<ul>
<?php foreach ($errors as $error): ?>
    <li><?php echo $error ?></li>
<?php endforeach ?>
</ul>
<?php endif ?>

<?php echo Form::open() ?>
<dl>
    <dt><?php echo Form::label('title', 'title') ?></dt>
    <dd><?php echo Form::input('title', $validator['title']) ?></dd>
    <dt><?php echo Form::label('post', 'post') ?></dt>
    <dd><?php echo Form::input('post', $validator['post']) ?></dd>
</dl>
<?php echo Form::submit(NULL, 'Post') ?>
<?php echo Form::close() ?>
<?php if ($recent_posts): ?>
<ul>
<?php foreach ($recent_posts as $post): ?>
    <li><?php echo $post['title'] . ' - ' . $post['post'];?></li>
<?php endforeach ?>
</ul>
<?php endif ?>

To get this code working in a default install, you would have to enable the database module and configure it for authentication. Then you can access it from index.php/news using default configuration.

It is tested in Kohana 3.0.7 and should give you a good starting point of how you might lay out code. Unlike other frameworks, Kohana seems to be very open ended as to where you put your logic so this is just what made sense to me. If you want to use the ORM instead of rolling your own database interaction, it has its own syntax for validation which you can find here