inanzzz | Creating a custom twig extension which doesn't accept parameters

We're going to encrypt a value with a custom twig extension in the example below. No parameter can be passed to this extension.

Extension Class

# sport/src/Football/FrontendBundle/Twig/EncryptExtension.php
namespace Football\FrontendBundle\Twig;

use Twig_Extension;
use Twig_SimpleFilter;

class EncryptExtension extends Twig_Extension
{
    public function getName()
    {
        return 'encrypt_extension';
    }

    public function getFilters()
    {
        return array(
            new Twig_SimpleFilter(
                'encrypt',
                array($this, 'encryptFilter')
            )
        );
    }

    public function encryptFilter($value)
    {
        return sha1($value);
    }
}

Config

# sport/src/Football/FrontendBundle/Resources/config/services.yml
services:
    football_frontend.twig.extension.encrypt:
        class: Football\FrontendBundle\Twig\EncryptExtension
        public: false
        tags:
            - { name: twig.extension }

Twig

Assuming that name variable is set in default controller and carries "inanzzz" as its value.

Hello {{ name }}!
<br />
Hello {{ name|encrypt }}!

Test

If you call http://sport.local/app_dev.php in your browser, you should see output below.

Hello inanzzz! 
Hello bae9e624ee464e275fa804d047955bcc08caab5b!