Nuno Mariz Weblog

This is the first part of an attempt to implement the ActiveRecord design pattern in PHP.
This first implementation is very simple but will open doors for more advanced stuff, like foreign keys mapping(automatic or manually) or integration with Model, View and Controller components, in this case with the generation of PHP classes or objects.

Approach: A row in a database table or view is wrapped into a class, thus an object instance is tied to a single row in the database.

Imagine this table(person):

+-------------+---------------------+
| Field       | Type                |
+-------------+---------------------+
| id          | bigint(20) unsigned |
| name        | varchar(100)        |
| email       | varchar(150)        |
| last_update | datetime            |
+-------------+---------------------+

With this records:

+----+----------+---------------+---------------------+
| id | name     | email         | last_update         |
+----+----------+---------------+---------------------+
|  1 | Nuno     | nuno@xxx.xxx  | 2005-11-06 20:39:08 |
+----+----------+---------------+---------------------+
|  2 | Marta    | marta@xxx.xxx | 2005-11-06 20:39:08 |
+----+----------+---------------+---------------------+
|  3 | Pedro    | joao@xxx.xxx  | 2005-11-06 20:39:08 |
+----+----------+---------------+---------------------+

You don’t have to define any table structure, just extend de ActiveRecord class and call the parent __construct() method with the table name :

<?php

include_once ‘class.ActiveRecord.php’;

class Person extends ActiveRecord {
    public function __construct() {
        parent::__construct(‘person’);
    }
}

?>

To return all rows in the table:

<?php

$persons = new Person();

/**
 * This will print all records
 * $persons->findAll() will return a Recordset
 */
foreach($persons->findAll() as $person) {
    echo ‘id: ‘.$person->id;
    echo ‘name: ‘.$person->name;
    echo ‘email: ‘.$person->email;
    echo ‘last update: ‘.$person->last_update;
}

/**
 * Alternatively you can ‘walk’ the Recordset
 * with next(), prev(), etc. because Recordset
 * implements the Iterator interface
 */

?>

Insert a record:

<?php

$person = new Person();
$person->name = ‘Julia’;
$person->email = ‘julia@xxx.xxx’;
$person->insert();

?>

Update a record:

<?php

$personId = $_POST[‘id’];
$person = new Person();
$person->id = $personId;
$person->name = ‘Nuno Mariz’;
$person->update();

?>

UPDATE:
With the Pádraic Brady tip for merging the insert() and update() methods to only one save() method, now is possible to:

<?php

// insert
$person = new Person();
$person->name = ‘Nuno Mariz’;
$person->save();

// or update
$personId = $_POST[‘id’];
$person = new Person();
$person->find($personId);
$person->name = ‘Nuno Mariz’;
$person->save();

?>

You can view the UML for the implementation.
See you in part II…

php|architect has posted the recorded version of their Zend Framework webcast on their site.
I must say is quite impressive. I’ve been developing a new framework to take advantage of the new features of PHP5.
Right now is quite mature and is in prodution, but lacks of some features.
One of the features that is missing is the ActiveRecord that Zend will implement in their new framework.
Quite curious is the ZMail, have almost the same API of my Mailer class.
One of the aspects that im also curious is the ZForms, right now in my framework is quite flexible. I can extend my FormManager class and add the elements that i need, like this:

<?php

include_once ‘class.FormManager.php’;

class FormLogin extends FormManager {
  public function __construct() {
    /*
     * Calling the parent
     * Usage::
     * parent::__construct($name,
     *                     $action = null,
     *                     $method = null,
     *                     $enctype = null,
     *                     $extra = null);
     */
    parent::__construct(‘FormLogin’, null, ‘POST’, null, null);
  }

  // Must implement this method
  public function initElements() {
    /*
     * Adding an Hidden Element
     * Usage:
     * $this->addHiddenElement($name, $value);
     */
    $this->addHiddenElement(‘module’, ‘Authentication’);
    $this->addHiddenElement(‘action’, ‘login’);

     /*
     * Adding an Element
     * Usage:
     * $this->addElement($type, $name, $label, $options);
     */
    $usernameOptions = array(…)
    $this->addElement(‘text’,
                      ‘username’,
                      ‘Username’,
                      $usernameOptions);

     /*
     * Adding a Validator
     * Usage:
     * $this->addValidator($elementName, $validatorObject);
     */
    $this->addValidator(‘username’,
                        new RequiredValidator());
    $this->addValidator(‘username’,
                        new MaxLengthValidator(array(‘length’=>15)));

    $passwordOptions = array(…)
    $this->addElement(‘password’,
                      ‘password’,
                      ‘Password’,
                      $usernameOptions);

    $loginOptions = array(…);
    $this->addElement(’submit’, ‘login’, ‘Login’, $loginOptions);
  }
}

$form = new FormLogin();
$form->render(); // render HTML form
echo $form->getFormStart();
// show the Username label
echo $form->getElementLabel(‘username’);
// show the Username imput
echo $form->getElementInput(‘username’);
// show the Password label
echo $form->getElementLabel(‘password’);
// show the Password input
echo $form->getElementInput(‘password’);
// show the Login submit button
echo $form->getElementInput(‘login’); // show the Login submit button
echo $form->getFormEnd();

?>

Another way is to load the XML configuration for the form:

<?php

include_once ‘class.XMLFormManager.php’;

$form = new XMLFormManager(‘FormLogin.xml’);
$form->render(); // render HTML form
echo $form->getFormStart();
echo $form->getElementLabel(‘username’); // show the Username label
echo $form->getElementInput(‘username’); // show the Username imput
echo $form->getElementLabel(‘password’); // show the Password label
echo $form->getElementInput(‘password’); // show the Password input
echo $form->getElementInput(‘login’); // show the Login submit button
echo $form->getFormEnd();

?>

In the XML way is quicker, i have a web application to generate the XML automatically. I can create or load XML forms and edit with an interface. I can bind elements with database table fields, add and configure validators, etc.

Recently i’ve improved the package to support the binding of an element with a database table field, the syntax is similary but with 2 more parameters in the addElement() method.

WOW. Im already anxious to see this working.
One thing that think that is missing in PHP, is the existence of an web application framework or an Application Server, which standardizes the way PHP applications are built.

What is the PHP Collaboration Project?
The PHP Collaboration Project is an open source initiative through which the PHP community and partners will create an industrial-grade PHP Web application development and deployment environment…

Zend PHP Framework
A Web application framework which standardizes the way PHP applications are built. The Zend PHP Framework accelerates and improves the development and deployment of mission-critical PHP Web applications.

By Joel’s Corner

Using templates that are PHP files

Including templates inside templates

Caching with expired system in seconds or without expiration

Caching with id’s

Plugin system, as simple as you can get

<html>
<body>
{include file="header.tpl"}
Title: {$title} 
List: 
{foreach from=$list item=list_item}
{$list_item} 
{/foreach}
</body>
</htm>

<?php

require_once(‘lib/smarty/Smarty.class.php’);

$smarty =& new Smarty();
$smarty->template_dir = ’smarty/templates/’;
$smarty->compile_dir = ’smarty/templates_c/’;
$smarty->cache_dir = ’smarty/cache/’;
$smarty->caching = 1;

$smarty->assign(‘title’, ‘My Title’);
$smarty->assign(‘intro’, ‘The intro paragraph.’);
$smarty->assign(‘list’, array(‘cat’, ‘dog’, ‘mouse’));
$smarty->fetch(‘index.tpl’);

?>

<html>
<body>
<?=$this->includeTemplate("header.tpl");?>
Title: <?=$title;?> <br />
List: <br />
<?php foreach ($list as $item):?>
<?=$item;?> <br />
<?php endforeach; ?>
<html>
<body>

<?php

require_once(‘lib/Template.php’);

$tpl =& new Template();
$tpl->setTemplatesPath(‘templates/’);
$tpl->setCache(true);
$tpl->setCachePath(‘cache/’);
$tpl->setCacheId(‘nuno’);
$tpl->setExpire(0);

$tpl->assign(‘title’, ‘My Title’);
$tpl->assign(‘intro’, ‘The intro paragraph.’);
$tpl->assign(‘list’, array(‘cat’, ‘dog’, ‘mouse’));
$tpl->fetch(‘index.tpl’);

?>

After one of the major database company (SAP recently launched a new PHP Development Forum), Oracle launches new PHP Developer section on the OTN.

Among other things you can read this interesting guides:

Is great to see that large companies are becoming aware that PHP has moved from a thriving open source project to an enterprise solution for web applications.