Symfony
sponsored by SensioLabs
Menu
  • About
  • Documentation
  • Screencasts
  • Cloud
  • Certification
  • Community
  • Businesses
  • News
  • Download
  1. Home
  2. Documentation
  3. Cookbook
  4. Templating
  5. How to Write a custom Twig Extension
  • Documentation
  • Book
  • Reference
  • Bundles
  • Cloud
Search by Algolia

Table of Contents

  • Create the Extension Class
  • Register an Extension as a Service
  • Using the custom Extension
  • Learning further

How to Write a custom Twig Extension

Edit this page

Warning: You are browsing the documentation for Symfony 2.3, which is no longer maintained.

Read the updated version of this page for Symfony 6.2 (the current stable version).

How to Write a custom Twig Extension

The main motivation for writing an extension is to move often used code into a reusable class like adding support for internationalization. An extension can define tags, filters, tests, operators, global variables, functions, and node visitors.

Creating an extension also makes for a better separation of code that is executed at compilation time and code needed at runtime. As such, it makes your code faster.

Tip

Before writing your own extensions, have a look at the Twig official extension repository.

Create the Extension Class

Note

This cookbook describes how to write a custom Twig extension as of Twig 1.12. If you are using an older version, please read Twig extensions documentation legacy.

To get your custom functionality you must first create a Twig Extension class. As an example you'll create a price filter to format a given number into price:

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
// src/AppBundle/Twig/AppExtension.php
namespace AppBundle\Twig;

class AppExtension extends \Twig_Extension
{
    public function getFilters()
    {
        return array(
            new \Twig_SimpleFilter('price', array($this, 'priceFilter')),
        );
    }

    public function priceFilter($number, $decimals = 0, $decPoint = '.', $thousandsSep = ',')
    {
        $price = number_format($number, $decimals, $decPoint, $thousandsSep);
        $price = '$'.$price;

        return $price;
    }

    public function getName()
    {
        return 'app_extension';
    }
}

Tip

Along with custom filters, you can also add custom `functions` and register `global variables`.

Register an Extension as a Service

Now you must let the Service Container know about your newly created Twig Extension:

  • YAML
  • XML
  • PHP
1
2
3
4
5
6
7
# app/config/services.yml
services:
    app.twig_extension:
        class: AppBundle\Twig\AppExtension
        public: false
        tags:
            - { name: twig.extension }
1
2
3
4
5
6
7
8
<!-- app/config/services.xml -->
<services>
    <service id="app.twig_extension"
        class="AppBundle\Twig\AppExtension"
        public="false">
        <tag name="twig.extension" />
    </service>
</services>
1
2
3
4
5
6
7
// app/config/services.php
use Symfony\Component\DependencyInjection\Definition;

$container
    ->register('app.twig_extension', '\AppBundle\Twig\AppExtension')
    ->setPublic(false)
    ->addTag('twig.extension');

Note

Keep in mind that Twig Extensions are not lazily loaded. This means that there's a higher chance that you'll get a ServiceCircularReferenceException or a ScopeWideningInjectionException if any services (or your Twig Extension in this case) are dependent on the request service. For more information take a look at How to Work with Scopes.

Using the custom Extension

Using your newly created Twig Extension is no different than any other:

1
2
{# outputs $5,500.00 #}
{{ '5500'|price }}

Passing other arguments to your filter:

1
2
{# outputs $5500,2516 #}
{{ '5500.25155'|price(4, ',', '') }}

Learning further

For a more in-depth look into Twig Extensions, please take a look at the Twig extensions documentation.

This work, including the code samples, is licensed under a Creative Commons BY-SA 3.0 license.
We stand with Ukraine.
Version:
Code consumes server resources. Blackfire tells you how

Code consumes server resources. Blackfire tells you how

Peruse our complete Symfony & PHP solutions catalog for your web development needs.

Peruse our complete Symfony & PHP solutions catalog for your web development needs.

↓ Our footer now uses the colors of the Ukrainian flag because Symfony stands with the people of Ukraine.

Avatar of Tobias Bönner, a Symfony contributor

Thanks Tobias Bönner for being a Symfony contributor

3 commits • 710 lines changed

View all contributors that help us make Symfony

Become a Symfony contributor

Be an active part of the community and contribute ideas, code and bug fixes. Both experts and newcomers are welcome.

Learn how to contribute

Symfony™ is a trademark of Symfony SAS. All rights reserved.

  • What is Symfony?
    • Symfony at a Glance
    • Symfony Components
    • Case Studies
    • Symfony Releases
    • Security Policy
    • Logo & Screenshots
    • Trademark & Licenses
    • symfony1 Legacy
  • Learn Symfony
    • Symfony Docs
    • Symfony Book
    • Reference
    • Bundles
    • Best Practices
    • Training
    • eLearning Platform
    • Certification
  • Screencasts
    • Learn Symfony
    • Learn PHP
    • Learn JavaScript
    • Learn Drupal
    • Learn RESTful APIs
  • Community
    • SymfonyConnect
    • Support
    • How to be Involved
    • Code of Conduct
    • Events & Meetups
    • Projects using Symfony
    • Downloads Stats
    • Contributors
    • Backers
  • Blog
    • Events & Meetups
    • A week of symfony
    • Case studies
    • Cloud
    • Community
    • Conferences
    • Diversity
    • Documentation
    • Living on the edge
    • Releases
    • Security Advisories
    • SymfonyInsight
    • Twig
    • SensioLabs
  • Services
    • SensioLabs services
    • Train developers
    • Manage your project quality
    • Improve your project performance
    • Host Symfony projects
    Deployed on
Follow Symfony
Search by Algolia