twig_extensions.rst

Twig Extensions

This section explains the basics of how to implement and use a custom Twig extension.

1. Create the Extension Class

Create the SiteExtention.php file following this folder structure:

YourNamespace/YourBundle/Twig/Extension/SiteExtension.php

Then define the namespace, and the class like the example below:

<?php

    namespace YourNamespace\SiteBundle\Twig\Extension;

    class SiteExtension extends \Twig_Extension
    {
        public function getName()
        {
            return 'site_extension';
        }

        public function getFilters()
        {
            return [
                new \Twig_SimpleFilter('yourfiltername', [$this, 'YourFunctionName'], array('is_safe' => array('html'))),
            ];
        }

        public function YourFunctionName($parameter)
        {
            return [];
        }
    }

2. Register an Extension as a Service

In src/YourNamespace/YourBundle/config/services.yml file, add those lines:

# TwigExtensions
YourNamespace.twig.site_extension:
        class: YourNamespace\YourBundle\Twig\Extension\SiteExtension
        tags:
                - { name: twig.extension }

3. Using the custom Extension

In your Twig template, use your custom filter like any other:

{{ 'some text'|yourfiltername }}

See more documentation here: Custom Twig Extension