stoimen.com/blog » zend framework

Zend_Validate_Db_RecordExists in Zend Framework 1.10+

Stoimen — Thu, 22 Jul 2010 11:24:46 +0000

Zend_Validate_Db_RecodExists is an extremely useful validator in Zend Framework when you’d like to be sure that a give row exists. Now it seems to be even better. Before you could check for a specific row by only comparing a value to the specified column:

$validator = new Zend_Validate_Db_RecordExists('db_table_name', 'column_name');
if ($validator->isValid(122)) {
   ...
}

which made it useless when you’d like to compare by more than one column. Now this is changed and you can even exclude given rows by adding an exclude clause.

$validator = new Zend_Validate_Db_NoRecordExists(
    array(
        'table' => 'users',
        'field' => 'username',
        'exclude' => array(
            'field' => 'id',
            'value' => $user_id
        )
    )
);

Setting Up Global Cache in Zend Framework

Stoimen — Wed, 21 Jul 2010 11:17:48 +0000

In a large scale web application, especially based on Zend Framework, there are lot’s of components that support built in cache support. Such are Zend_Db, Zend_Translate, Zend_Date, etc. Also you may need cache support wherever in the app, so my advice is to setup a cache instance in the “beginning”, into the bootstrap.php or even better – into a front controller plugin, and to store it into the Zend_Registry. Thus you’ve to change only the lifetime for specific needs:


 
class CacheInit extends Zend_Controller_Plugin_Abstract
{
    public function __construct()
    {
        $frontendOptions = array(
            'automatic_serialization' => true,
            'lifetime' => 60
        );
 
        $backendOptions  = array(
            'cache_dir' => realpath(APPLICATION_PATH . '/../cache')
        );
 
        $cache = Zend_Cache::factory('Core',
                                     'File',
                                     $frontendOptions,
                                     $backendOptions);
 
        Zend_Registry::set('cache', $cache);
    }
}

Than add it as a front controller plugin:

// cache plugin
$frontController->registerPlugin(new CacheInit());

Zend Framework: Connect MySQL

Stoimen — Tue, 20 Jul 2010 11:12:45 +0000

There are so many tutorials about that, but let me add it one more time. You’ve to use the PDO_MYSQL adapter:

// where params include adapter, host
// username, password and dbname
$db = new Zend_Db_Adapter_Pdo_Mysql($params);

and set the default adapter

Zend_Db_Table::setDefaultAdapter($db);

That can be done in the bootstrap or into a front controller plugin!

Zend Framework: Cache Database Table Schemes

Stoimen — Mon, 19 Jul 2010 11:03:04 +0000

If you’re familiar with Zend Framework, you should know how to turn your database tables into models. Simply extend the Zend_Db_Table class. This is the very general example. There are lots of variations how to name the model classes and what member variables they can have.


class User extends Zend_Db_Table
{}

The question is …

The question is how the framework knows what columns there are in a given table. That’s done by PHP on every call of the class, and the question is: isn’t that too slow? Yes it is and there’s a solution – to cache the table’s schema:

Zend_Db_Table_Abstract::setDefaultMetadataCache($cache);

Is there any problem?

Why it isn’t a default behavior when it’s so good? Because you’ve first to setup the cache, which is not always permitted – at least you’ve to have writing permissions. And on the second place if you’re rapidly developing the system and you change the database schema too frequently, you’ve to clear the cache every time. So it’s a good solution for the production server, but you can skip it while developing.

Zend_Mail with GMail

Stoimen — Sun, 18 Jul 2010 11:39:20 +0000

You know how to setup Zend_Mail with SMTP, but you don’t know how to set it up with GMail! Here’s how to do it. Just follow the instructions

$mailTransport = new Zend_Mail_Transport_Smtp('smtp.gmail.com', array(
    'auth'     => 'login',
    'username' => 'xxxxxx@gmail.com',
    'password' => 'passxxxxx',
    'port'     => '587',
    'ssl'      => 'tls',
));
Zend_Mail::setDefaultTransport($mailTransport);

Send Html Mails with Zend_Mail

Stoimen — Sat, 17 Jul 2010 11:31:47 +0000

Typically you’d never like to send a non-html formatted mail from your web system. It’s ugly and it’s difficult to read. Instead of sending pure text, you’d like to add some images and styles. The way you can do it with Zend_Mail is simple enough. Replace the setBody method with setBodyHtml. Isn’t that natural?

// before
$mail = new Zend_Mail('utf-8');
$mail->setFrom('sender@example.com', 'Sender Name');
$mail->setBody('message in Html');
$mail->addTo('recipient@example.com', 'Recepient Name');
$mail->setSubject('Subject');
$mail->send();

// after
$mail = new Zend_Mail('utf-8');
$mail->setFrom('sender@example.com', 'Sender Name');
$mail->setBodyHtml('message in Html');
$mail->addTo('recipient@example.com', 'Recepient Name');
$mail->setSubject('Subject');
$mail->send();

Media RSS and ZF – Part 2

Stoimen — Wed, 14 Jul 2010 19:05:15 +0000

Here’s the promised chunk of code making the most simple bridge between Zend Framework and Media RSS.

Step 1

Just add a simple action in a controller:

class IndexController extends Zend_Controller_Action
{
	public function indexAction()
	{
	    $this->getResponse()->setHeader('Content-Type', 'application/xml');
	    $this->view->somevar = 'some value';
 
	    echo $this->view->render('index/index.xml');
 
	    $this->_helper->layout()->disableLayout();
	    $this->_helper->viewRenderer->setNoRender(true);
	}
}

Step 2

After you’ve setup the xml file as a view script – you can simply access it as a normal Zend Framework view:

 version="2.0" xmlns:media="http://search.yahoo.com/mrss/" xmlns:av="http://www.searchvideo.com/schemas/av/1.0">
  >
   > echo $this->somevar ?>>
   ...
   other media rss elements
   ...
>
>

Zend Framework and Media RSS

Stoimen — Tue, 13 Jul 2010 19:23:32 +0000

The Problem

Since native RSS format is not designed to deliver media content, there is a need for newer format supporting video and audio. There is such format – Media RSS introduced by Yahoo! in 2004. Actually now RSS supports some king of pseudo audio and video with the enclosure tag.

Although there is a standardized format, there is not a Zend Framework native module. There is however a proposal, but that’s far not enough.

Possible Solutions

For me there are two possible solutions. The first is writing Zend_Feed_Mrss and extend the Zend_Feed_Rss functionality, but that appears to be a non-trivial task. The second solution is to write custom view returning XML, which I’m choosing for now. I hope I can paste some code soon!

Default Error Handling in Zend Framework

Stoimen — Wed, 07 Jul 2010 09:28:59 +0000

Zend_Controller_Action_Exception

There’s a cool feature in Zend Framework when a controller or action doesn’t exists. That’s really useful, because you simply write an ErrorController.php in you default module and every action’s exception sends the user to this controller/action and the job is done for you. What is important here is to show the error message at least on the development stage. Actually the request stores it as a parameter. Here’s some source:


 
class ErrorController extends Zend_Controller_Action
{
    public function errorAction()
    {
        $errorHandler = $this->getRequest()->getParam('error_handler');
        /* @var $error Zend_Controller_Action_Exception */
        $error = $errorHandler->exception;
        echo $error->getMessage();
    }
}

Zend Framework: Simple Acl Front Controller Plugin

Stoimen — Tue, 06 Jul 2010 19:00:59 +0000

Almost every web site need some abstraction over the access control list (ACL) to grant access of its users. As usual Zend Framework has quite good mechanism to deal with this – Zend_Acl.

Out in the web there are a lot of resources about Zend_Acl’s usage, so I ain’t going to cover it one more time, but simply copy/paste a very small front controller plugin implementing the basic usage of Zend_Acl.

Note that instead of defining the __construct() here is called preDispatch where the request is passed as a parameter. However only by copy pasting not every answer will be given. That’s why I’m going to write more about Zend_Acl in my future posts, for now only the source code:


 
class AclInit extends Zend_Controller_Plugin_Abstract
{
    public function preDispatch(Zend_Controller_Request_Abstract $request)
    {
        // create new acl object
        $acl = new Zend_Acl();
 
        // define resources. typically there are
        // only four resources from the CRUD functionality
        // but there can be added more resources
        $acl->add(new Zend_Acl_Resource('index'))
            ->add(new Zend_Acl_Resource('create'))
            ->add(new Zend_Acl_Resource('read'))
            ->add(new Zend_Acl_Resource('update'))
            ->add(new Zend_Acl_Resource('delete'));
 
        // define roles
        $acl->addRole(new Zend_Acl_Role('guest'))
            ->addRole(new Zend_Acl_Role('admin'));
 
        // define privileges
        $acl->allow('guest', array('index', 'read'))
            ->allow('admin');
 
        // setup acl in the registry for more
        Zend_Registry::set('acl', $acl);
 
        // check permissions
        if (!$acl->isAllowed('guest', $request->getActionName())) {
            $request->setControllerName('error');
            $request->setActionName('error');
        }
    }
}