Twig functions

Drupal Twig Functions

When to Use

When you need to generate URLs, attach libraries, create links, or use other Drupal-specific functions from within a Twig template.

Items

url(route_name, parameters, options)

Description: Generates an absolute URL. Returns a render array with bubbled cache metadata. Usage:

{{ url('entity.node.canonical', {node: node.id()}) }}
{{ url('<front>') }}

Gotchas: Returns a GeneratedUrl object, not a plain string. For string-safe use, prefer path().

path(route_name, parameters, options)

Description: Generates a relative path (no scheme/host). Usage:

<a href="{{ path('entity.user.canonical', {user: user.id()}) }}">Profile</a>

Gotchas: Safe for HTML context when parameters are simple (one constant param). Multiple parameters may need escaping.

link(text, url, attributes)

Description: Returns a render array for an <a> element. Preferred over manual <a href> for internal links. Usage:

{{ link('Read more'|t, url) }}
{{ link(node.label, 'internal:/node/' ~ node.id(), {'class': ['read-more']}) }}

Gotchas: url can be a string URI or a Url object. Text can be a translated string or markup.

file_url(uri)

Description: Converts a public://... file URI to a web-accessible URL. Usage:

<img src="{{ file_url(node.field_image.entity.fileUri) }}" alt="{{ node.field_image.alt }}">

Gotchas: Input must be a URI (public://, private://, base:). Passing a path instead of URI returns wrong URL.

attach_library(library)

Description: Attaches a CSS/JS library to the response from within a template. Usage:

{{ attach_library('mytheme/my-component') }}
{{ attach_library('core/drupal.dialog') }}

Gotchas: Returns empty string (nothing to print). Use {{ attach_library(...) }} not {% set x = attach_library(...) %}. Prefer attaching in preprocess or #attached for performance.

active_theme()

Description: Returns the machine name of the active theme. Usage:

{% if active_theme() == 'mytheme' %}...{% endif %}

active_theme_path()

Description: Returns the path to the active theme. Usage:

<img src="{{ active_theme_path() }}/images/logo.svg">

Gotchas: Avoid hard-coded asset paths this way — use #attached libraries instead.

create_attribute(attributes)

Description: Creates a new Attribute object for use in templates. Usage:

{% set wrapper_attrs = create_attribute({'class': ['my-wrapper'], 'data-type': node.bundle}) %}
<div{{ wrapper_attrs }}>

render_var(variable)

Description: Renders a render array to a string. Rarely needed directly — Twig's print already calls it. Usage:

{% set rendered = render_var(content.field_body) %}
{% if rendered|trim is not empty %}
  {{ rendered }}
{% endif %}

Common Mistakes

• Using {{ path() }} without checking if parameters are safe → multiple variable params need extra care
• Using {{ active_theme_path() }} for referencing images/assets → wrong approach; use #attached libraries or file_url() with the file URI
• Calling {{ file_url(node.field_image.entity.fileUri) }} without checking if entity exists → fatal if field is empty

See Also

• Drupal Twig filters → Drupal Twig Filters
• Core source: core/lib/Drupal/Core/Template/TwigExtension.php