ViewsBlock.php

<?php

namespace Drupal\views\Plugin\Derivative;

use Drupal\Core\Entity\EntityStorageInterface;
use Drupal\Core\Plugin\Discovery\ContainerDeriverInterface;
use Drupal\Core\StringTranslation\TranslatableMarkup;
use Symfony\Component\DependencyInjection\ContainerInterface;

/**
 * Provides block plugin definitions for all Views block displays.
 *
 * @see \Drupal\views\Plugin\Block\ViewsBlock
 */
class ViewsBlock implements ContainerDeriverInterface {

  /**
   * List of derivative definitions.
   *
   * @var array
   */
  protected $derivatives = [];

  /**
   * The base plugin ID.
   *
   * @var string
   */
  protected $basePluginId;

  /**
   * The view storage.
   *
   * @var \Drupal\Core\Entity\EntityStorageInterface
   */
  protected $viewStorage;

  /**
   * {@inheritdoc}
   */
  public static function create(ContainerInterface $container, $base_plugin_id) {
    return new static($base_plugin_id, $container
      ->get('entity_type.manager')
      ->getStorage('view'));
  }

  /**
   * Constructs a ViewsBlock object.
   *
   * @param string $base_plugin_id
   *   The base plugin ID.
   * @param \Drupal\Core\Entity\EntityStorageInterface $view_storage
   *   The entity storage to load views.
   */
  public function __construct($base_plugin_id, EntityStorageInterface $view_storage) {
    $this->basePluginId = $base_plugin_id;
    $this->viewStorage = $view_storage;
  }

  /**
   * {@inheritdoc}
   */
  public function getDerivativeDefinition($derivative_id, $base_plugin_definition) {
    if (!empty($this->derivatives) && !empty($this->derivatives[$derivative_id])) {
      return $this->derivatives[$derivative_id];
    }
    $this
      ->getDerivativeDefinitions($base_plugin_definition);
    return $this->derivatives[$derivative_id];
  }

  /**
   * {@inheritdoc}
   */
  public function getDerivativeDefinitions($base_plugin_definition) {

    // Check all Views for block displays.
    foreach ($this->viewStorage
      ->loadMultiple() as $view) {

      // Do not return results for disabled views.
      if (!$view
        ->status()) {
        continue;
      }
      $executable = $view
        ->getExecutable();
      $executable
        ->initDisplay();
      foreach ($executable->displayHandlers as $display) {

        /** @var \Drupal\views\Plugin\views\display\DisplayPluginInterface $display */

        // Add a block plugin definition for each block display.
        if (isset($display) && !empty($display->definition['uses_hook_block'])) {
          $delta = $view
            ->id() . '-' . $display->display['id'];
          $admin_label = $display
            ->getOption('block_description');
          if (empty($admin_label)) {
            if ($display->display['display_title'] == $display->definition['title']) {
              $admin_label = $view
                ->label();
            }
            else {

              // Allow translators to control the punctuation. Plugin
              // definitions get cached, so use TranslatableMarkup() instead of
              // $this->t() to avoid double escaping when $admin_label is rendered
              // during requests that use the cached definition.
              $admin_label = new TranslatableMarkup('@view: @display', [
                '@view' => $view
                  ->label(),
                '@display' => $display->display['display_title'],
              ]);
            }
          }
          $this->derivatives[$delta] = [
            'category' => $display
              ->getOption('block_category'),
            'admin_label' => $admin_label,
            'config_dependencies' => [
              'config' => [
                $view
                  ->getConfigDependencyName(),
              ],
            ],
          ];

          // Look for arguments and expose them as context.
          foreach ($display
            ->getHandlers('argument') as $argument_name => $argument) {

            /** @var \Drupal\views\Plugin\views\argument\ArgumentPluginBase $argument */
            if ($context_definition = $argument
              ->getContextDefinition()) {
              $this->derivatives[$delta]['context_definitions'][$argument_name] = $context_definition;
            }
          }
          $this->derivatives[$delta] += $base_plugin_definition;
        }
      }
    }
    return $this->derivatives;
  }

}