class RouteSubscriber

class RouteSubscriber extends RouteSubscriberBase {
    
    /**
     * The entity type manager service.
     *
     * @var \Drupal\Core\Entity\EntityTypeManagerInterface
     */
    protected $entityTypeManager;
    
    /**
     * Constructs a RouteSubscriber object.
     *
     * @param \Drupal\Core\Entity\EntityTypeManagerInterface $entity_type_manager
     *   The entity type manager service.
     */
    public function __construct(EntityTypeManagerInterface $entity_type_manager) {
        $this->entityTypeManager = $entity_type_manager;
    }
    
    /**
     * {@inheritdoc}
     */
    protected function alterRoutes(RouteCollection $collection) {
        foreach ($this->entityTypeManager
            ->getDefinitions() as $entity_type_id => $entity_type) {
            if ($route_name = $entity_type->get('field_ui_base_route')) {
                // Try to get the route from the current collection.
                if (!($entity_route = $collection->get($route_name))) {
                    continue;
                }
                $path = $entity_route->getPath();
                $options = $entity_route->getOptions();
                if ($bundle_entity_type = $entity_type->getBundleEntityType()) {
                    $options['parameters'][$bundle_entity_type] = [
                        'type' => 'entity:' . $bundle_entity_type,
                    ];
                }
                // Special parameter used to easily recognize all Field UI routes.
                $options['_field_ui'] = TRUE;
                $defaults = [
                    'entity_type_id' => $entity_type_id,
                ];
                // If the entity type has no bundles and it doesn't use {bundle} in its
                // admin path, use the entity type.
                if (strpos($path, '{bundle}') === FALSE) {
                    $defaults['bundle'] = !$entity_type->hasKey('bundle') ? $entity_type_id : '';
                }
                $route = new Route("{$path}/fields/{field_config}", [
                    '_entity_form' => 'field_config.edit',
                    '_title_callback' => '\\Drupal\\field_ui\\Form\\FieldConfigEditForm::getTitle',
                ] + $defaults, [
                    '_entity_access' => 'field_config.update',
                ], $options);
                $collection->add("entity.field_config.{$entity_type_id}_field_edit_form", $route);
                $route = new Route("{$path}/fields/{field_config}/storage", [
                    '_entity_form' => 'field_storage_config.edit',
                ] + $defaults, [
                    '_permission' => 'administer ' . $entity_type_id . ' fields',
                ], $options);
                $collection->add("entity.field_config.{$entity_type_id}_storage_edit_form", $route);
                $route = new Route("{$path}/fields/{field_config}/delete", [
                    '_entity_form' => 'field_config.delete',
                ] + $defaults, [
                    '_entity_access' => 'field_config.delete',
                ], $options);
                $collection->add("entity.field_config.{$entity_type_id}_field_delete_form", $route);
                $route = new Route("{$path}/fields", [
                    '_controller' => '\\Drupal\\field_ui\\Controller\\FieldConfigListController::listing',
                    '_title' => 'Manage fields',
                ] + $defaults, [
                    '_permission' => 'administer ' . $entity_type_id . ' fields',
                ], $options);
                $collection->add("entity.{$entity_type_id}.field_ui_fields", $route);
                $route = new Route("{$path}/fields/add-field", [
                    '_form' => '\\Drupal\\field_ui\\Form\\FieldStorageAddForm',
                    '_title' => 'Add field',
                ] + $defaults, [
                    '_permission' => 'administer ' . $entity_type_id . ' fields',
                ], $options);
                $collection->add("field_ui.field_storage_config_add_{$entity_type_id}", $route);
                $route = new Route("{$path}/form-display", [
                    '_entity_form' => 'entity_form_display.edit',
                    '_title' => 'Manage form display',
                    'form_mode_name' => 'default',
                ] + $defaults, [
                    '_field_ui_form_mode_access' => 'administer ' . $entity_type_id . ' form display',
                ], $options);
                $collection->add("entity.entity_form_display.{$entity_type_id}.default", $route);
                $route = new Route("{$path}/form-display/{form_mode_name}", [
                    '_entity_form' => 'entity_form_display.edit',
                    '_title' => 'Manage form display',
                ] + $defaults, [
                    '_field_ui_form_mode_access' => 'administer ' . $entity_type_id . ' form display',
                ], $options);
                $collection->add("entity.entity_form_display.{$entity_type_id}.form_mode", $route);
                $route = new Route("{$path}/display", [
                    '_entity_form' => 'entity_view_display.edit',
                    '_title' => 'Manage display',
                    'view_mode_name' => 'default',
                ] + $defaults, [
                    '_field_ui_view_mode_access' => 'administer ' . $entity_type_id . ' display',
                ], $options);
                $collection->add("entity.entity_view_display.{$entity_type_id}.default", $route);
                $route = new Route("{$path}/display/{view_mode_name}", [
                    '_entity_form' => 'entity_view_display.edit',
                    '_title' => 'Manage display',
                ] + $defaults, [
                    '_field_ui_view_mode_access' => 'administer ' . $entity_type_id . ' display',
                ], $options);
                $collection->add("entity.entity_view_display.{$entity_type_id}.view_mode", $route);
            }
        }
    }
    
    /**
     * {@inheritdoc}
     */
    public static function getSubscribedEvents() {
        $events = parent::getSubscribedEvents();
        $events[RoutingEvents::ALTER] = [
            'onAlterRoutes',
            -100,
        ];
        return $events;
    }

}