Drupal Render

Drupal Render Arrays

Basic Structure

$build = [
  '#type' => 'container',
  '#attributes' => ['class' => ['my-wrapper']],
  'content' => [
    '#markup' => $this->t('Hello world'),
  ],
];

Cache Metadata (Always Required)

$build['content'] = [
  '#markup' => $output,
  '#cache' => [
    'tags' => ['node:' . $node->id(), 'node_list'],
    'contexts' => ['user.permissions', 'url.query_args'],
    'max-age' => 3600,
  ],
];

Cache Tag Conventions

| Tag | Invalidates when | |---|---| | node:123 | Node 123 is saved | | node_list | Any node is created/deleted | | user:456 | User 456 is saved | | taxonomy_term:789 | Term 789 is saved | | config:my_module.settings | Config is saved | | block_content:1 | Block content is saved |

Cache Contexts

| Context | Varies by | |---|---| | user | Current user identity | | user.permissions | User's permissions | | user.roles | User's roles | | url | Full URL | | url.path | URL path only | | url.query_args | Query string | | languages | Current language | | session | Session data | | theme | Active theme |

Markup Safety

// Plain text — always safe
$build['#plain_text'] = $user_input;

// Trusted markup — use Markup class
use Drupal\Core\Render\Markup;
$build['#markup'] = Markup::create('Safe');

// User input in markup — filter first
use Drupal\Component\Utility\Xss;
$build['#markup'] = Markup::create(Xss::filter($user_input));

// Admin-level markup — allows more tags
$build['#markup'] = Markup::create(Xss::filterAdmin($html));

Render Elements

// HTML tag
$build['heading'] = [
  '#type' => 'html_tag',
  '#tag' => 'h2',
  '#value' => $this->t('Title'),
  '#attributes' => ['class' => ['my-heading']],
];

// Link
$build['link'] = [
  '#type' => 'link',
  '#title' => $this->t('Go'),
  '#url' => Url::fromRoute('entity.node.canonical', ['node' => $nid]),
  '#attributes' => ['class' => ['button']],
];

// Entity view
$build['node'] = $this->entityTypeManager
  ->getViewBuilder('node')
  ->view($node, 'teaser');

// Inline template
$build['inline'] = [
  '#type' => 'inline_template',
  '#template' => '{{ content }}',
  '#context' => ['class' => 'my-class', 'content' => $content],
];

Lazy Builder (Uncacheable Content)

$build['dynamic'] = [
  '#lazy_builder' => [
    'my_module.service:buildDynamicContent',
    [$arg1, $arg2],
  ],
  '#create_placeholder' => TRUE,
];

Rendering Programmatically

// Inject renderer service
public function __construct(
  private readonly RendererInterface $renderer,
) {}

// Render to string
$html = $this->renderer->render($build);

// Render in isolated context (doesn't bubble cache)
$html = $this->renderer->renderInIsolation($build);

Source & license

This open-source skill is cataloged on AgentStack and links to its original source — we do not rehost the code.

• Author: edutrul
• Source: edutrul/drupal-ai
• License: MIT
• Homepage: https://eduardotelaya.com/drupal-ai/

Install and usage instructions live in the source repository linked above.