class PathBasedBreadcrumbBuilder in Drupal 8

Class to define the menu_link breadcrumb builder.

Hierarchy

• class \Drupal\system\PathBasedBreadcrumbBuilder implements BreadcrumbBuilderInterface uses StringTranslationTrait

1 file declares its use of PathBasedBreadcrumbBuilder

PathBasedBreadcrumbBuilderTest.php in core/modules/system/tests/src/Unit/Breadcrumbs/PathBasedBreadcrumbBuilderTest.php

Contains \Drupal\Tests\system\Unit\Breadcrumbs\PathBasedBreadcrumbBuilderTest.

1 string reference to 'PathBasedBreadcrumbBuilder'

system.services.yml in core/modules/system/system.services.yml

core/modules/system/system.services.yml

1 service uses PathBasedBreadcrumbBuilder

system.breadcrumb.default in core/modules/system/system.services.yml

Drupal\system\PathBasedBreadcrumbBuilder

File

core/modules/system/src/PathBasedBreadcrumbBuilder.php, line 31

Namespace

Drupal\system

class PathBasedBreadcrumbBuilder implements BreadcrumbBuilderInterface {
  use StringTranslationTrait;

  /**
   * The router request context.
   *
   * @var \Drupal\Core\Routing\RequestContext
   */
  protected $context;

  /**
   * The menu link access service.
   *
   * @var \Drupal\Core\Access\AccessManagerInterface
   */
  protected $accessManager;

  /**
   * The dynamic router service.
   *
   * @var \Symfony\Component\Routing\Matcher\RequestMatcherInterface
   */
  protected $router;

  /**
   * The inbound path processor.
   *
   * @var \Drupal\Core\PathProcessor\InboundPathProcessorInterface
   */
  protected $pathProcessor;

  /**
   * Site config object.
   *
   * @var \Drupal\Core\Config\Config
   */
  protected $config;

  /**
   * The title resolver.
   *
   * @var \Drupal\Core\Controller\TitleResolverInterface
   */
  protected $titleResolver;

  /**
   * The current user object.
   *
   * @var \Drupal\Core\Session\AccountInterface
   */
  protected $currentUser;

  /**
   * The current path service.
   *
   * @var \Drupal\Core\Path\CurrentPathStack
   */
  protected $currentPath;

  /**
   * The patch matcher service.
   *
   * @var \Drupal\Core\Path\PathMatcherInterface
   */
  protected $pathMatcher;

  /**
   * Constructs the PathBasedBreadcrumbBuilder.
   *
   * @param \Drupal\Core\Routing\RequestContext $context
   *   The router request context.
   * @param \Drupal\Core\Access\AccessManagerInterface $access_manager
   *   The menu link access service.
   * @param \Symfony\Component\Routing\Matcher\RequestMatcherInterface $router
   *   The dynamic router service.
   * @param \Drupal\Core\PathProcessor\InboundPathProcessorInterface $path_processor
   *   The inbound path processor.
   * @param \Drupal\Core\Config\ConfigFactoryInterface $config_factory
   *   The config factory service.
   * @param \Drupal\Core\Controller\TitleResolverInterface $title_resolver
   *   The title resolver service.
   * @param \Drupal\Core\Session\AccountInterface $current_user
   *   The current user object.
   * @param \Drupal\Core\Path\CurrentPathStack $current_path
   *   The current path.
   * @param \Drupal\Core\Path\PathMatcherInterface $path_matcher
   *   The path matcher service.
   */
  public function __construct(RequestContext $context, AccessManagerInterface $access_manager, RequestMatcherInterface $router, InboundPathProcessorInterface $path_processor, ConfigFactoryInterface $config_factory, TitleResolverInterface $title_resolver, AccountInterface $current_user, CurrentPathStack $current_path, PathMatcherInterface $path_matcher = NULL) {
    $this->context = $context;
    $this->accessManager = $access_manager;
    $this->router = $router;
    $this->pathProcessor = $path_processor;
    $this->config = $config_factory
      ->get('system.site');
    $this->titleResolver = $title_resolver;
    $this->currentUser = $current_user;
    $this->currentPath = $current_path;
    $this->pathMatcher = $path_matcher ?: \Drupal::service('path.matcher');
  }

  /**
   * {@inheritdoc}
   */
  public function applies(RouteMatchInterface $route_match) {
    return TRUE;
  }

  /**
   * {@inheritdoc}
   */
  public function build(RouteMatchInterface $route_match) {
    $breadcrumb = new Breadcrumb();
    $links = [];

    // Add the url.path.parent cache context. This code ignores the last path
    // part so the result only depends on the path parents.
    $breadcrumb
      ->addCacheContexts([
      'url.path.parent',
      'url.path.is_front',
    ]);

    // Do not display a breadcrumb on the frontpage.
    if ($this->pathMatcher
      ->isFrontPage()) {
      return $breadcrumb;
    }

    // General path-based breadcrumbs. Use the actual request path, prior to
    // resolving path aliases, so the breadcrumb can be defined by simply
    // creating a hierarchy of path aliases.
    $path = trim($this->context
      ->getPathInfo(), '/');
    $path_elements = explode('/', $path);
    $exclude = [];

    // Don't show a link to the front-page path.
    $front = $this->config
      ->get('page.front');
    $exclude[$front] = TRUE;

    // /user is just a redirect, so skip it.
    // @todo Find a better way to deal with /user.
    $exclude['/user'] = TRUE;
    while (count($path_elements) > 1) {
      array_pop($path_elements);

      // Copy the path elements for up-casting.
      $route_request = $this
        ->getRequestForPath('/' . implode('/', $path_elements), $exclude);
      if ($route_request) {
        $route_match = RouteMatch::createFromRequest($route_request);
        $access = $this->accessManager
          ->check($route_match, $this->currentUser, NULL, TRUE);

        // The set of breadcrumb links depends on the access result, so merge
        // the access result's cacheability metadata.
        $breadcrumb = $breadcrumb
          ->addCacheableDependency($access);
        if ($access
          ->isAllowed()) {
          $title = $this->titleResolver
            ->getTitle($route_request, $route_match
            ->getRouteObject());
          if (!isset($title)) {

            // Fallback to using the raw path component as the title if the
            // route is missing a _title or _title_callback attribute.
            $title = str_replace([
              '-',
              '_',
            ], ' ', Unicode::ucfirst(end($path_elements)));
          }
          $url = Url::fromRouteMatch($route_match);
          $links[] = new Link($title, $url);
        }
      }
    }

    // Add the Home link.
    $links[] = Link::createFromRoute($this
      ->t('Home'), '<front>');
    return $breadcrumb
      ->setLinks(array_reverse($links));
  }

  /**
   * Matches a path in the router.
   *
   * @param string $path
   *   The request path with a leading slash.
   * @param array $exclude
   *   An array of paths or system paths to skip.
   *
   * @return \Symfony\Component\HttpFoundation\Request
   *   A populated request object or NULL if the path couldn't be matched.
   */
  protected function getRequestForPath($path, array $exclude) {
    if (!empty($exclude[$path])) {
      return NULL;
    }
    $request = Request::create($path);

    // Performance optimization: set a short accept header to reduce overhead in
    // AcceptHeaderMatcher when matching the request.
    $request->headers
      ->set('Accept', 'text/html');

    // Find the system path by resolving aliases, language prefix, etc.
    $processed = $this->pathProcessor
      ->processInbound($path, $request);
    if (empty($processed) || !empty($exclude[$processed])) {

      // This resolves to the front page, which we already add.
      return NULL;
    }
    $this->currentPath
      ->setPath($processed, $request);

    // Attempt to match this path to provide a fully built request.
    try {
      $request->attributes
        ->add($this->router
        ->matchRequest($request));
      return $request;
    } catch (ParamNotConvertedException $e) {
      return NULL;
    } catch (ResourceNotFoundException $e) {
      return NULL;
    } catch (MethodNotAllowedException $e) {
      return NULL;
    } catch (AccessDeniedHttpException $e) {
      return NULL;
    }
  }

}

Members

Name	Modifiers	Type	Description	Overrides
PathBasedBreadcrumbBuilder::$accessManager	protected	property	The menu link access service.
PathBasedBreadcrumbBuilder::$config	protected	property	Site config object.
PathBasedBreadcrumbBuilder::$context	protected	property	The router request context.
PathBasedBreadcrumbBuilder::$currentPath	protected	property	The current path service.
PathBasedBreadcrumbBuilder::$currentUser	protected	property	The current user object.
PathBasedBreadcrumbBuilder::$pathMatcher	protected	property	The patch matcher service.
PathBasedBreadcrumbBuilder::$pathProcessor	protected	property	The inbound path processor.
PathBasedBreadcrumbBuilder::$router	protected	property	The dynamic router service.
PathBasedBreadcrumbBuilder::$titleResolver	protected	property	The title resolver.
PathBasedBreadcrumbBuilder::applies	public	function	Whether this breadcrumb builder should be used to build the breadcrumb. Overrides BreadcrumbBuilderInterface::applies
PathBasedBreadcrumbBuilder::build	public	function	Builds the breadcrumb. Overrides BreadcrumbBuilderInterface::build
PathBasedBreadcrumbBuilder::getRequestForPath	protected	function	Matches a path in the router.
PathBasedBreadcrumbBuilder::__construct	public	function	Constructs the PathBasedBreadcrumbBuilder.
StringTranslationTrait::$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.