class PlaceholderGenerator
Same name in other branches
- 9 core/lib/Drupal/Core/Render/PlaceholderGenerator.php \Drupal\Core\Render\PlaceholderGenerator
- 8.9.x core/lib/Drupal/Core/Render/PlaceholderGenerator.php \Drupal\Core\Render\PlaceholderGenerator
- 11.x core/lib/Drupal/Core/Render/PlaceholderGenerator.php \Drupal\Core\Render\PlaceholderGenerator
Turns a render array into a placeholder.
Hierarchy
- class \Drupal\Core\Render\PlaceholderGenerator implements \Drupal\Core\Render\PlaceholderGeneratorInterface
Expanded class hierarchy of PlaceholderGenerator
1 file declares its use of PlaceholderGenerator
- RendererTestBase.php in core/
tests/ Drupal/ Tests/ Core/ Render/ RendererTestBase.php
1 string reference to 'PlaceholderGenerator'
- core.services.yml in core/
core.services.yml - core/core.services.yml
1 service uses PlaceholderGenerator
File
-
core/
lib/ Drupal/ Core/ Render/ PlaceholderGenerator.php, line 15
Namespace
Drupal\Core\RenderView source
class PlaceholderGenerator implements PlaceholderGeneratorInterface {
/**
* The cache contexts manager service.
*
* @var \Drupal\Core\Cache\Context\CacheContextsManager
*/
protected $cacheContextsManager;
/**
* The renderer configuration array.
*
* @var array
*/
protected $rendererConfig;
/**
* Constructs a new Placeholder service.
*
* @param \Drupal\Core\Cache\Context\CacheContextsManager $cache_contexts_manager
* The cache contexts manager service.
* @param array $renderer_config
* The renderer configuration array.
*/
public function __construct(CacheContextsManager $cache_contexts_manager, array $renderer_config) {
$this->cacheContextsManager = $cache_contexts_manager;
$this->rendererConfig = $renderer_config;
}
/**
* {@inheritdoc}
*/
public function canCreatePlaceholder(array $element) {
// If generated by a #lazy_builder callback, placeholdering is possible.
return isset($element['#lazy_builder']) && (!isset($element['#create_placeholder']) || $element['#create_placeholder'] !== FALSE);
}
/**
* {@inheritdoc}
*/
public function shouldAutomaticallyPlaceholder(array $element) {
// Auto-placeholder if the max-age, cache context or cache tag is specified
// in the auto-placeholder conditions in the 'renderer.config' container
// parameter.
$conditions = $this->rendererConfig['auto_placeholder_conditions'];
$cacheability = CacheableMetadata::createFromRenderArray($element);
if ($cacheability->getCacheMaxAge() !== Cache::PERMANENT && $cacheability->getCacheMaxAge() <= $conditions['max-age']) {
return TRUE;
}
// Optimize the contexts and let them affect the cache tags to mimic what
// happens to the cacheability in the variation cache (RenderCache backend).
$cacheability->addCacheableDependency($this->cacheContextsManager
->convertTokensToKeys($cacheability->getCacheContexts()));
$cacheability->setCacheContexts($this->cacheContextsManager
->optimizeTokens($cacheability->getCacheContexts()));
if (array_intersect($cacheability->getCacheContexts(), $conditions['contexts'])) {
return TRUE;
}
if (array_intersect($cacheability->getCacheTags(), $conditions['tags'])) {
return TRUE;
}
return FALSE;
}
/**
* {@inheritdoc}
*/
public function createPlaceholder(array $element) {
$placeholder_render_array = array_intersect_key($element, [
// Placeholders are replaced with markup by executing the associated
// #lazy_builder callback, which generates a render array, and which the
// Renderer will render and replace the placeholder with.
'#lazy_builder' => TRUE,
// The cacheability metadata for the placeholder. The rendered result of
// the placeholder may itself be cached, if [#cache][keys] are specified.
'#cache' => TRUE,
]);
if (isset($element['#lazy_builder_preview'])) {
$placeholder_render_array['#preview'] = $element['#lazy_builder_preview'];
}
// Be sure cache contexts and tags are sorted before serializing them and
// making hash. Issue #3225328 removes sort from contexts and tags arrays
// for performances reasons.
if (isset($placeholder_render_array['#cache']['contexts'])) {
sort($placeholder_render_array['#cache']['contexts']);
}
if (isset($placeholder_render_array['#cache']['tags'])) {
sort($placeholder_render_array['#cache']['tags']);
}
// Generate placeholder markup. Note that the only requirement is that this
// is unique markup that isn't easily guessable. The #lazy_builder callback
// and its arguments are put in the placeholder markup solely to simplify<<<
// debugging.
$callback = $placeholder_render_array['#lazy_builder'][0];
$arguments = UrlHelper::buildQuery($placeholder_render_array['#lazy_builder'][1]);
$token = Crypt::hashBase64(serialize($placeholder_render_array));
$placeholder_markup = '<drupal-render-placeholder callback="' . Html::escape($callback) . '"';
if ($arguments !== '') {
$placeholder_markup .= ' arguments="' . Html::escape($arguments) . '"';
}
$placeholder_markup .= ' token="' . Html::escape($token) . '"></drupal-render-placeholder>';
// Build the placeholder element to return.
$placeholder_element = [];
$placeholder_element['#markup'] = Markup::create($placeholder_markup);
$placeholder_element['#attached']['placeholders'][$placeholder_markup] = $placeholder_render_array;
return $placeholder_element;
}
}
Members
Title Sort descending | Modifiers | Object type | Summary |
---|---|---|---|
PlaceholderGenerator::$cacheContextsManager | protected | property | The cache contexts manager service. |
PlaceholderGenerator::$rendererConfig | protected | property | The renderer configuration array. |
PlaceholderGenerator::canCreatePlaceholder | public | function | |
PlaceholderGenerator::createPlaceholder | public | function | |
PlaceholderGenerator::shouldAutomaticallyPlaceholder | public | function | |
PlaceholderGenerator::__construct | public | function | Constructs a new Placeholder service. |
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