Issue #2359213: Stub out actually checking access.

src/FillPdfAccessController.php

 <?php
 /**
-  * @file
-  * Contains \Drupal\fillpdf\FillPdfAccessController.
-  */
+ * @file
+ * Contains \Drupal\fillpdf\FillPdfAccessController.
+ */
 
 namespace Drupal\fillpdf;
 
 use Drupal\Core\Access\AccessResult;
+use Drupal\Core\DependencyInjection\ContainerInjectionInterface;
+use Symfony\Component\DependencyInjection\ContainerInterface;
+use Symfony\Component\HttpFoundation\RequestStack;
 
-class FillPdfAccessController {
+class FillPdfAccessController implements ContainerInjectionInterface {
+
+  /** @var FillPdfLinkManipulatorInterface $linkManipulator */
+  protected $linkManipulator;
+
+  /** @var RequestStack $requestStack */
+  protected $requestStack;
+
+  /** @var FillPdfContextManagerInterface $contextManager */
+  protected $contextManager;
+
+  public function __construct(FillPdfLinkManipulatorInterface $link_manipulator, FillPdfContextManagerInterface $context_manager, RequestStack $request_stack) {
+    $this->linkManipulator = $link_manipulator;
+    $this->contextManager = $context_manager;
+    $this->requestStack = $request_stack;
+  }
+
+  /**
+   * {@inheritDoc}
+   */
+  public static function create(ContainerInterface $container) {
+    return new static($container->get('fillpdf.link_manipulator'), $container->get('fillpdf.context_manager'), $container->get('request_stack'));
+  }
+
+  public function checkLink() {
+    $context = $this->linkManipulator->parseLink($this->requestStack->getCurrentRequest());
+
+    // TODO: samples can be viewed by admins
+    if ($context['sample']) {
+      // ...
+    }
+
+    $entities = $this->contextManager->loadEntities($context);
+
+    foreach ($entities as $entity_type => $entity_objects) {
+      // If there are any entities in the context that the user can't view,
+      // deny access.
+      // TODO: return AccessResult:forbiddenIf accordingly
+    }
 
-  function checkLink() {
-    // TODO: Actually do access checking here
     return AccessResult::allowedIf(TRUE);
   }