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class SiteAlertBlock in Site Alert 8

Implements SiteAlertBlock class.

Plugin annotation


@Block(
  id = "site_alert_block",
  admin_label = @Translation("Site Alert"),
)

Hierarchy

Expanded class hierarchy of SiteAlertBlock

2 files declare their use of SiteAlertBlock
SiteAlertCacheTest.php in tests/src/Functional/SiteAlertCacheTest.php
site_alert.module in ./site_alert.module
Allows admins to display a site-wide alert to all users.

File

src/Plugin/Block/SiteAlertBlock.php, line 24

Namespace

Drupal\site_alert\Plugin\Block
View source 
class SiteAlertBlock extends BlockBase implements ContainerFactoryPluginInterface {

  /**
   * The default timeout for refreshing site alerts.
   */
  const TIMEOUT_DEFAULT = 300;

  /**
   * The service that retrieves site alerts.
   *
   * @var \Drupal\site_alert\GetAlertsInterface
   */
  protected $getAlerts;

  /**
   * The entity type manager.
   *
   * @var \Drupal\Core\Entity\EntityTypeManagerInterface
   */
  protected $entityTypeManager;

  /**
   * The module handler.
   *
   * @var \Drupal\Core\Extension\ModuleHandlerInterface
   */
  protected $moduleHandler;

  /**
   * Constructs a new SiteAlertBlock.
   *
   * @param array $configuration
   *   A configuration array containing information about the plugin instance.
   * @param string $plugin_id
   *   The plugin_id for the plugin instance.
   * @param mixed $plugin_definition
   *   The plugin implementation definition.
   * @param \Drupal\site_alert\GetAlertsInterface $getAlerts
   *   The service that retrieves site alerts.
   * @param \Drupal\Core\Entity\EntityTypeManagerInterface $entityTypeManager
   *   The entity type manager service.
   * @param \Drupal\Core\Extension\ModuleHandlerInterface $moduleHandler
   *   The module handler.
   */
  public function __construct(array $configuration, $plugin_id, $plugin_definition, GetAlertsInterface $getAlerts, EntityTypeManagerInterface $entityTypeManager, ModuleHandlerInterface $moduleHandler) {
    if (empty($entity_type_manager)) {
      @trigger_error('Omitting the entity type manager when instantiating ' . __METHOD__ . ' is deprecated in site_alert:8.x-1.1 and will throw an error in site_alert:9.x-1.0. Make sure to pass the entity type manager instead. See https://www.drupal.org/project/site_alert/issues/3118227', E_USER_DEPRECATED);
      $entityTypeManager = \Drupal::entityTypeManager();
    }
    parent::__construct($configuration, $plugin_id, $plugin_definition);
    $this->getAlerts = $getAlerts;
    $this->entityTypeManager = $entityTypeManager;
    $this->moduleHandler = $moduleHandler;
  }

  /**
   * {@inheritdoc}
   */
  public static function create(ContainerInterface $container, array $configuration, $plugin_id, $plugin_definition) {
    return new static($configuration, $plugin_id, $plugin_definition, $container
      ->get('site_alert.get_alerts'), $container
      ->get('entity_type.manager'), $container
      ->get('module_handler'));
  }

  /**
   * {@inheritdoc}
   */
  public function build() {
    $build = [];
    $metadata = new CacheableMetadata();

    // Due to a bug in Drupal core the cache max age is ignored when the core
    // page_cache module is enabled. This bug prevents any cached pages from
    // being invalidated in time for a scheduled alert to be displayed. We can
    // work around this by injecting the JS code in the page and letting it
    // retrieve the first alert on page load. This means that even if the page
    // is cached it will poll the server for any available alerts and display
    // them. The drawback is that this will always cause a second request to be
    // sent which increases server load, so only do this if any alerts are
    // actually scheduled.
    // @todo Remove this workaround when the core bug is fixed.
    // @see https://www.drupal.org/project/site_alert/issues/3121988

    /** @var \Drupal\site_alert\SiteAlertStorage $storage */
    $storage = $this->entityTypeManager
      ->getStorage('site_alert');
    $scheduled_alerts_present = $storage
      ->getCacheMaxAge() !== CacheBackendInterface::CACHE_PERMANENT;
    $workaround_needed = $scheduled_alerts_present && $this->moduleHandler
      ->moduleExists('page_cache');
    $alerts = $this->getAlerts
      ->getActiveAlerts();
    foreach ($alerts as $alert) {
      $metadata
        ->addCacheableDependency($alert);

      // Avoid displaying the alert if we need to work around the core bug. This
      // prevents site alerts from briefly flashing in the page in case the bug
      // prevents a cached page that contains an alert from being invalidated.
      if ($workaround_needed) {
        continue;
      }
      $build[] = [
        '#theme' => 'site_alert',
        '#alert' => [
          'severity' => $alert
            ->getSeverity(),
          'label' => $alert
            ->getLabel(),
          'message' => [
            '#type' => 'markup',
            '#markup' => $alert
              ->getMessage(),
          ],
        ],
      ];
    }

    // Attach the JS code to refresh the site alerts when a timeout is
    // configured.
    $timeout = $this
      ->getConfiguration()['timeout'];
    if ($timeout > 0 || $workaround_needed) {
      $build['#attached'] = [
        'library' => [
          'site_alert/drupal.site_alert',
        ],
        'drupalSettings' => [
          'siteAlert' => [
            'timeout' => $timeout,
            'workaround_needed' => $workaround_needed,
          ],
        ],
      ];
    }
    if (!empty($build)) {
      $build['#prefix'] = '<div class="site-alert" aria-live="polite">';
      $build['#suffix'] = '</div>';
    }
    $metadata
      ->applyTo($build);
    return $build;
  }

  /**
   * {@inheritdoc}
   */
  public function defaultConfiguration() {
    return [
      'timeout' => self::TIMEOUT_DEFAULT,
    ] + parent::defaultConfiguration();
  }

  /**
   * {@inheritdoc}
   */
  public function buildConfigurationForm(array $form, FormStateInterface $form_state) {
    $form = parent::buildConfigurationForm($form, $form_state);
    $timeout = $this
      ->getConfiguration()['timeout'];
    $form['timeout'] = [
      '#type' => 'number',
      '#title' => $this
        ->t('Timeout'),
      '#description' => $this
        ->t('After how many seconds the alerts should be refreshed. Set to 0 if you do not wish to poll the server for updates.'),
      '#default_value' => $timeout,
      '#field_suffix' => ' ' . $this
        ->t('seconds'),
      '#required' => TRUE,
      '#min' => 0,
    ];
    return $form;
  }

  /**
   * {@inheritdoc}
   */
  public function submitConfigurationForm(array &$form, FormStateInterface $form_state) {
    parent::submitConfigurationForm($form, $form_state);
    $this
      ->setConfigurationValue('timeout', $form_state
      ->getValue('timeout'));
  }

  /**
   * {@inheritdoc}
   */
  public function getCacheTags() {

    // The block should be invalidated whenever any site alert changes.
    $list_cache_tags = $this->entityTypeManager
      ->getDefinition('site_alert')
      ->getListCacheTags();
    return Cache::mergeTags(parent::getCacheTags(), $list_cache_tags);
  }

  /**
   * {@inheritdoc}
   */
  public function getCacheContexts() {
    return Cache::mergeContexts(parent::getCacheContexts(), [
      'active_site_alerts',
    ]);
  }

  /**
   * {@inheritdoc}
   */
  public function getCacheMaxAge() {

    /** @var \Drupal\site_alert\SiteAlertStorageInterface $storage */
    $storage = $this->entityTypeManager
      ->getStorage('site_alert');
    return $storage
      ->getCacheMaxAge();
  }

}

Members

Namesort descending Modifiers Type Description Overrides
BlockPluginInterface::BLOCK_LABEL_VISIBLE constant Indicates the block label (title) should be displayed to end users.
BlockPluginTrait::$transliteration protected property The transliteration service.
BlockPluginTrait::access public function
BlockPluginTrait::baseConfigurationDefaults protected function Returns generic default configuration for block plugins.
BlockPluginTrait::blockAccess protected function Indicates whether the block should be shown. 16
BlockPluginTrait::blockForm public function 16
BlockPluginTrait::blockSubmit public function 13
BlockPluginTrait::blockValidate public function 3
BlockPluginTrait::calculateDependencies public function
BlockPluginTrait::getConfiguration public function 1
BlockPluginTrait::getMachineNameSuggestion public function 1
BlockPluginTrait::getPreviewFallbackString public function 3
BlockPluginTrait::label public function
BlockPluginTrait::setConfiguration public function
BlockPluginTrait::setConfigurationValue public function
BlockPluginTrait::setTransliteration public function Sets the transliteration service.
BlockPluginTrait::transliteration protected function Wraps the transliteration service.
BlockPluginTrait::validateConfigurationForm public function Most block plugins should not override this method. To add validation for a specific block type, override BlockBase::blockValidate(). 1
ContextAwarePluginAssignmentTrait::addContextAssignmentElement protected function Builds a form element for assigning a context to a given slot.
ContextAwarePluginAssignmentTrait::contextHandler protected function Wraps the context handler.
ContextAwarePluginBase::$context protected property The data objects representing the context of this plugin.
ContextAwarePluginBase::$contexts Deprecated private property Data objects representing the contexts passed in the plugin configuration.
ContextAwarePluginBase::createContextFromConfiguration protected function Overrides ContextAwarePluginBase::createContextFromConfiguration
ContextAwarePluginBase::getContext public function This code is identical to the Component in order to pick up a different Context class. Overrides ContextAwarePluginBase::getContext
ContextAwarePluginBase::getContextDefinition public function Overrides ContextAwarePluginBase::getContextDefinition
ContextAwarePluginBase::getContextDefinitions public function Overrides ContextAwarePluginBase::getContextDefinitions
ContextAwarePluginBase::getContextMapping public function Gets a mapping of the expected assignment names to their context names. Overrides ContextAwarePluginInterface::getContextMapping
ContextAwarePluginBase::getContexts public function Gets the defined contexts. Overrides ContextAwarePluginInterface::getContexts
ContextAwarePluginBase::getContextValue public function Gets the value for a defined context. Overrides ContextAwarePluginInterface::getContextValue
ContextAwarePluginBase::getContextValues public function Gets the values for all defined contexts. Overrides ContextAwarePluginInterface::getContextValues
ContextAwarePluginBase::setContext public function Set a context on this plugin. Overrides ContextAwarePluginBase::setContext
ContextAwarePluginBase::setContextMapping public function Sets a mapping of the expected assignment names to their context names. Overrides ContextAwarePluginInterface::setContextMapping
ContextAwarePluginBase::setContextValue public function Sets the value for a defined context. Overrides ContextAwarePluginBase::setContextValue
ContextAwarePluginBase::validateContexts public function Validates the set values for the defined contexts. Overrides ContextAwarePluginInterface::validateContexts
ContextAwarePluginBase::__get public function Implements magic __get() method.
DependencySerializationTrait::$_entityStorages protected property An array of entity type IDs keyed by the property name of their storages.
DependencySerializationTrait::$_serviceIds protected property An array of service IDs keyed by property name used for serialization.
DependencySerializationTrait::__sleep public function 1
DependencySerializationTrait::__wakeup public function 2
MessengerTrait::$messenger protected property The messenger. 29
MessengerTrait::messenger public function Gets the messenger. 29
MessengerTrait::setMessenger public function Sets the messenger.
PluginBase::$configuration protected property Configuration information passed into the plugin. 1
PluginBase::$pluginDefinition protected property The plugin implementation definition. 1
PluginBase::$pluginId protected property The plugin_id.
PluginBase::DERIVATIVE_SEPARATOR constant A string which is used to separate base plugin IDs from the derivative ID.
PluginBase::getBaseId public function Gets the base_plugin_id of the plugin instance. Overrides DerivativeInspectionInterface::getBaseId
PluginBase::getDerivativeId public function Gets the derivative_id of the plugin instance. Overrides DerivativeInspectionInterface::getDerivativeId
PluginBase::getPluginDefinition public function Gets the definition of the plugin implementation. Overrides PluginInspectionInterface::getPluginDefinition 3
PluginBase::getPluginId public function Gets the plugin_id of the plugin instance. Overrides PluginInspectionInterface::getPluginId
PluginBase::isConfigurable public function Determines if the plugin is configurable.
PluginWithFormsTrait::getFormClass public function
PluginWithFormsTrait::hasFormClass public function
SiteAlertBlock::$entityTypeManager protected property The entity type manager.
SiteAlertBlock::$getAlerts protected property The service that retrieves site alerts.
SiteAlertBlock::$moduleHandler protected property The module handler.
SiteAlertBlock::build public function Builds and returns the renderable array for this block plugin. Overrides BlockPluginInterface::build
SiteAlertBlock::buildConfigurationForm public function Creates a generic configuration form for all block types. Individual block plugins can add elements to this form by overriding BlockBase::blockForm(). Most block plugins should not override this method unless they need to alter the generic form elements. Overrides BlockPluginTrait::buildConfigurationForm
SiteAlertBlock::create public static function Creates an instance of the plugin. Overrides ContainerFactoryPluginInterface::create
SiteAlertBlock::defaultConfiguration public function Overrides BlockPluginTrait::defaultConfiguration
SiteAlertBlock::getCacheContexts public function The cache contexts associated with this object. Overrides ContextAwarePluginBase::getCacheContexts
SiteAlertBlock::getCacheMaxAge public function The maximum age for which this object may be cached. Overrides ContextAwarePluginBase::getCacheMaxAge
SiteAlertBlock::getCacheTags public function The cache tags associated with this object. Overrides ContextAwarePluginBase::getCacheTags
SiteAlertBlock::submitConfigurationForm public function Most block plugins should not override this method. To add submission handling for a specific block type, override BlockBase::blockSubmit(). Overrides BlockPluginTrait::submitConfigurationForm
SiteAlertBlock::TIMEOUT_DEFAULT constant The default timeout for refreshing site alerts.
SiteAlertBlock::__construct public function Constructs a new SiteAlertBlock. Overrides BlockPluginTrait::__construct
StringTranslationTrait::$stringTranslation protected property The string translation service. 1
StringTranslationTrait::formatPlural protected function Formats a string containing a count of items.
StringTranslationTrait::getNumberOfPlurals protected function Returns the number of plurals supported by a given language.
StringTranslationTrait::getStringTranslation protected function Gets the string translation service.
StringTranslationTrait::setStringTranslation public function Sets the string translation service to use. 2
StringTranslationTrait::t protected function Translates a string to the current language or to a given language.
TypedDataTrait::$typedDataManager protected property The typed data manager used for creating the data types.
TypedDataTrait::getTypedDataManager public function Gets the typed data manager. 2
TypedDataTrait::setTypedDataManager public function Sets the typed data manager. 2