Symfony2 - Load different templates based on user agent

If you want to load different templates for different user agents while keeping the same backend code base, you can accomplish this simply in 2 ways.

1.  Responsive Template
2. Load different templates against user agents.

In this blog post I'm trying to demonstrate the option 2 (load different templates against user agents)

The trick is to use RequestFormat in symfony

1. Create a Request Listener

php app/console generate:bundle --namespace=Acme/RequestListenerBundle --format=yml

Note: You don't need Controller, Tests directories

Past the below code to AcmeRequestListnerBundle.php

getRequest();

        if(preg_match('/(alcatel|amoi|android|avantgo|blackberry|benq|cell|cricket|docomo|elaine|htc|iemobile|iphone|ipad|ipaq|ipod|j2me|java|midp|mini|mmp|mobi|motorola|nec-|nokia|palm|panasonic|philips|phone|playbook|sagem|sharp|sie-|silk|smartphone|sony|symbian|t-mobile|telus|up\.browser|up\.link|vodafone|wap|webos|wireless|xda|xoom|zte)/i', $request->headers->get('user-agent')))
        {
            $request->setRequestFormat('mobile', 'text/html');
        }else {
            $request->setRequestFormat('html', 'text/html');
        }
    }

    private function setFormat (\Symfony\Component\HttpFoundation\Request $request, $format='html') {
        $request->setRequestFormat($format, 'text/html');
    }
}

2. Create a test action in your controller

Action 

    /**
     * @Route("/test", name="_demo_test")
     * @Template()
     */
    public function testAction()
    {
        return array(
            'name' => 'Thilanga Pitigala',
        );
    }

Note: Run

php app/console router:debug | grep _demo_test

and verify the newly created action and the router

Template

Create the template for newly created action

Acme/DemoBundle/Resources/views/Demo/test.html.twig

{% extends "AcmeDemoBundle::layout.html.twig" %}

{% block title "Hello " %}

{% block content %}
    

Hello Desktop !
{% endblock %}

2. Create a Service using RequestListener

Add below code to config.yml

services:
    acme.listener.request:
        class: Acme\RequestListenerBundle\AcmeRequestListenerBundle
        tags:
            - { name: kernel.event_listener, event: kernel.request, method: onKernelRequest }

Note: run

php app/console container:debug | grep acme.listener.request

  and That will output the newly created service

2. Test RequestListener service

Try visiting the web applications from mobile device. It will throw an error complaining about missing test.mobile.twig file.

Create the test.mobile.twig file in Acme/DemoBundle/Resources/views/Demo/test.html.twig as we created the test.html.twig template.

Now you will be able to see the mobile template from mobile devices while desktop template load for desktop agents.

By that way we can load different templates for different agents without doing any responsive templates.

Happy Coding..

Symfony2 - Setup an Application in a minute

1. Download

Download the Symfony Standard Edition from http://symfony.com/download (at the moment of writing this post latest stable version is 2.1)

cd /home/user/Downloads/
wget --content-disposition 'http://symfony.com/download?v=Symfony_Standard_Vendors_2.1.4.tgz'
tar -zxvf Symfony_Standard_Vendors_2.1.4.tgz
mv Symfony /var/www/symfony

Then Point /var/www/symfony/web directory to the your web server

2. Configuration

Now We are going to use app.php as the main index file instead of playing with app_dev.php within the development enviroment.

vim web/app.php

Replace your app.php with the below code

// Make group permissions stick in cache/log dirs
umask(0002);

use Symfony\Component\ClassLoader\ApcClassLoader;
use Symfony\Component\HttpFoundation\Request;

$loader = require_once __DIR__.'/../app/bootstrap.php.cache';
require_once __DIR__.'/../app/AppKernel.php';

$env = 'prod';

if (isset($_SERVER['HTTP_HOST'])) {
    if (preg_match('/(localhost|local\.)/', $_SERVER['HTTP_HOST'])) {
        $env = 'dev';
    }
}

$kernel = new AppKernel($env, $env == 'dev');
$kernel->loadClassCache();
$request = Request::createFromGlobals();
$response = $kernel->handle($request);
$response->send();
$kernel->terminate($request, $response);

Load your Symfony site by typing http://localhost/symfony in your web browser

Now you can access Symfony Development environment without visiting to app_dev.php.

Why Symfony2?

With the PHP5 there was a big hype in PHP frameworks and MVC pattern. As a result, lots of developers got lost within frameworks while trying to figure out the best.

I was one of them.

When it comes to PHP frameworks, ZEND, CodeIgniter were my favourites.  I used CodeIgniter for simple applications and ZEND framework was the giant who saved my good hours. But I never enjoyed PHP with frameworks. Frameworks are good for just get things done.

After I joined with August I got chance to work with Symfony. Not just Symfony, It's Symfony2 :)

Symfony2 is one of a kind framework, it is not a MVC framework. If you look at the Symfony2 architecture, you could find controllers, views but no models. It has been developed as a HTTP framework.

That is how the web works.

The biggest concern in Symfony2 is decoupling and from the core it has given reusable set of standalone components to use. Simply it has provided a set of tools to develop applications as we want.

At the beginning, I was really frustrated because it seems to be complicated and over engineered. however after few days of work I started liking how it works.

The most impressive part in Symfony2 is the 'Bundle' concept. If you write a Symfony2 bundle, simply you can run it within any Symfony2 project without a hassle.  A bundle contains it's own configurations, routing rules, actions, templates and business logic codes.

Dependency injection is another powerful feature which we can commonly see in JAVA developments. That means Symfony2 has adopted lots of best things from other languages without trying to reinvent the wheel.

According the the Symfony2 documentation, it contains 21 standalone libraries which we can use for day-to-day developments.

1. DependencyInjection
2. EventDispatcher
3. HttpFoundation
4. DomCrawler
5. ClassLoader
6. CssSelector
7. HttpKernel
8. BrowserKit
9. Templating
10. Translation
11. Serializer
12. Validator
13. Security
14. Routing
15. Console
16. Process
17. Config
18. Finder
19. Locale
20. Yaml
21. Form

It is not an easy task to explain the awesomeness of Symfony2 in a single blog post :)

This is going to be the very first of many blog posts about Symfony2. I'll be writing some tutorials specially for beginners who are willing to use Symfony2 in their next projects.