LayoutBuilderRoutes.php

<?php

namespace Drupal\layout_builder\Routing;

use Drupal\Core\Routing\RouteBuildEvent;
use Drupal\Core\Routing\RoutingEvents;
use Drupal\layout_builder\SectionStorage\SectionStorageManagerInterface;
use Symfony\Component\EventDispatcher\EventSubscriberInterface;

/**
 * Provides routes for the Layout Builder UI.
 *
 * @internal
 *   Tagged services are internal.
 */
class LayoutBuilderRoutes implements EventSubscriberInterface {
    
    /**
     * The section storage manager.
     *
     * @var \Drupal\layout_builder\SectionStorage\SectionStorageManagerInterface
     */
    protected $sectionStorageManager;
    
    /**
     * Constructs a new LayoutBuilderRoutes.
     *
     * @param \Drupal\layout_builder\SectionStorage\SectionStorageManagerInterface $section_storage_manager
     *   The section storage manager.
     */
    public function __construct(SectionStorageManagerInterface $section_storage_manager) {
        $this->sectionStorageManager = $section_storage_manager;
    }
    
    /**
     * Alters existing routes for a specific collection.
     *
     * @param \Drupal\Core\Routing\RouteBuildEvent $event
     *   The route build event.
     */
    public function onAlterRoutes(RouteBuildEvent $event) {
        $collection = $event->getRouteCollection();
        foreach ($this->sectionStorageManager
            ->getDefinitions() as $plugin_id => $definition) {
            $this->sectionStorageManager
                ->loadEmpty($plugin_id)
                ->buildRoutes($collection);
        }
    }
    
    /**
     * {@inheritdoc}
     */
    public static function getSubscribedEvents() : array {
        // Run after \Drupal\field_ui\Routing\RouteSubscriber.
        $events[RoutingEvents::ALTER] = [
            'onAlterRoutes',
            -110,
        ];
        return $events;
    }

}