Installing Twig

This really couldn’t get a lot simpler with pear:

    $ pear channel-discover pear.twig-project.org
    $ pear install twig/Twig

or, you can use the Git or Subversion repos as detailed on the projects website: http://www.twig-project.org/doc/intro.html

The Application Resource

Setting up a ZF application resource for twig is a snip! The minimal config required to set up a Twig instance, is exactly that, minimal!

Simple create the class “Core_Resource_Twig” and place it in library/Core/Resource/Twig.php and consider the following code:

<?php

class Core_Resource_Twig extends Zend_Application_Resource_ResourceAbstract
{
    /**
     * @var Twig_Environment
     */
    protected $twig;

    public function init()
    {
        $options = $this->getOptions();
        $loader = new Twig_Loader_Filesystem($options['templateDir']);
        $this->twig = new Twig_Environment(
                $loader,
                $options['options']
        );
        return $this->twig;
    }
}

All we are doing here, is creating an instance of the Filesystem Twig loader, which loads templates from files, and then passing that in to the Twig Environment, along with the rest of the options from our config, which in brief, would now look something like this:

[production]
autoloaderNamespaces[] = "Twig_"
pluginPaths.Core_Resource = APPLICATION_PATH "/../library/Core/Resource"

; FRONT CONTROLLER
resources.frontController.moduleDirectory = APPLICATION_PATH "/modules"
resources.frontController.controllerDirectory.default = APPLICATION_PATH "/controllers"
resources.frontController.noViewRenderer = true

; TWIG
resources.twig.templateDir = APPLICATION_PATH "/templates"
resources.twig.options.cache = APPLICATION_PATH "/../cache/twig"

[development : production]
resources.twig.options.debug = true
resources.twig.options.auto_reload = true

That now gives us two things, a configured Twig instance, and an application resource to hold it, which will be present in the invoke args in your controller. so for the next step, we stitch it together, and make it more useable, to make things super simple, a base controller class is useful here. The reason for a base controller class rather than an action helper is simple, performance, and simplicity; no need for the complexity or auto-rendering anything, we will simply call a method at the end of each action.

Given that we are now using twig, this has two benefits, we avoid the overhead of how ZF looks up the view name to decide which view template to render, which is a part of the bottleneck of ZF, and additionally, it matches more closely to the other documentation you’ll find on Twig elsewhere, and we are doing things in a slightly different manner to how we would use Zend_View, so why try to emulate it, when we are using something very different!

<?php

abstract class Core_Controller extends Zend_Controller_Action
{
    public function twig($template, array $vars)
    {
        $twig = $this->getBootstrap()->getResource('twig');

        $template = $twig->loadTemplate($template);
        $this->getResponse()->appendBody(
            $template->render($vars),
            'default'
        );
    }
}

Rendering the template

Now that we have our base controller class, we can now use our template, in this manner from our action:

<?php

class IndexController extends Core_Controller
{
    /**
     * @var Core_Service_Posts
     */
    protected $service;

    public function init()
    {
        $this->service = new Core_Service_Posts();
    }

    public function indexAction()
    {
        $recent = $this->service->recentPosts();
        $this->twig('home.twig', array(
            'recent' => $recent,
        ));
    }

    public function viewAction()
    {
        $id = $this->getRequest()->getParam('id', false);
        if (false === $id) {
            throw new Core_InvalidIdException('No ID Present');
        }

        $paste = $this->service->byId($id);

        $this->twig('view-post.twig', array(
            'post' => $paste,
        ));
    }

}

In this example, you have the indexAction, taking the service for the posts for the application, and passing the recent posts to the template, and in the view action, taking the selected post, and passes it to the template, with the selection of template for the action being passed as the first argument to our twig method we added to the base controller class.

And now, you can find examples and documentation on how to put together your twig templates here http://www.twig-project.org/documentation.