Merge pull request #9 from digitalutsc/issue-8

Fixes #8 - Thumbnail not loading when media is private

islandora_mirador.routing.yml

@@ -5,3 +5,9 @@ islandora_mirador.miradorconfig:
     _title: 'Mirador Settings'
   requirements:
     _permission: 'administer site configuration'
+islandora_mirador.service_worker:
+  path: '/islandora_mirador_service_worker'
+  defaults: 
+    _controller: '\Drupal\islandora_mirador\Controller\ServiceWorkerController::serve' 
+  requirements: 
+    _permission: 'access content'

js/mirador_viewer.js

@@ -76,6 +76,21 @@
                         ],
                     },
                 };
+
+                if ('serviceWorker' in navigator) {
+                    // The Mirador viewer uses img tags for thumbnails so thumbnail image requests
+                    // do not have authorization or token headers. Attach them using a service worker.
+                    window.addEventListener('load', () => {
+                        navigator.serviceWorker
+                            .register('/islandora_mirador_service_worker?token=' + settings.token, { scope: '/' })
+                            .then(registration => {
+                                console.log('ServiceWorker registration successful with scope: ', registration.scope);
+                            })
+                            .catch(err => {
+                                console.log('ServiceWorker registration failed: ', err);
+                            });
+                    });
+                }
             }
 
 

js/service_worker.js

@@ -0,0 +1,21 @@
+self.addEventListener('activate', function (event) {
+  console.log('Service Worker: claiming control...');
+  return self.clients.claim();
+});
+
+self.addEventListener('fetch', function (event) {
+  if (event.request.destination === "image" && new URL(event.request.url).pathname.startsWith('/cantaloupe/iiif/') && new URL(location).searchParams.has('token')) {
+    console.log('Service Worker: fetching...');
+    var token = new URL(location).searchParams.get('token');
+    event.respondWith(
+      fetch(event.request, {
+        headers: {
+          'Authorization': 'Bearer ' + token,
+          'token': token
+        },
+        mode: "cors",
+        credentials: "include"
+      })
+    );
+  }
+});

src/Controller/ServiceWorkerController.php

@@ -0,0 +1,58 @@
+<?php
+
+namespace Drupal\islandora_mirador\Controller;
+
+use Drupal\Core\Controller\ControllerBase;
+use Drupal\Core\Extension\ExtensionPathResolver;
+use Symfony\Component\DependencyInjection\ContainerInterface;
+use Symfony\Component\HttpFoundation\BinaryFileResponse;
+use Symfony\Component\HttpFoundation\Request;
+use Symfony\Component\HttpKernel\Exception\NotFoundHttpException;
+
+/**
+ * A controller for the Service Worker.
+ */
+class ServiceWorkerController extends ControllerBase {
+
+  /**
+   * The extension path resolver service.
+   *
+   * @var \Drupal\Core\Extension\ExtensionPathResolver
+   */
+  protected $extensionPathResolver;
+
+  /**
+   * Constructs a ServiceWorkerController object.
+   *
+   * @param \Drupal\Core\Extension\ExtensionPathResolver $extension_path_resolver
+   *   The extension path resolver service.
+   */
+  public function __construct(ExtensionPathResolver $extension_path_resolver) {
+    $this->extensionPathResolver = $extension_path_resolver;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public static function create(ContainerInterface $container) {
+    return new static(
+      $container->get('extension.path.resolver')
+    );
+  }
+
+  /**
+   * Adds headers to the HTTP response.
+   */
+  public function serve(Request $request) {
+    $file_str = $this->extensionPathResolver->getPath('module', 'islandora_mirador') . '/js/service_worker.js';
+    if (file_exists($file_str)) {
+      $response = new BinaryFileResponse($file_str, 200);
+      $response->headers->set('Content-Type', 'application/javascript');
+      // Allow same origin service worker.
+      $response->headers->set('Service-Worker-Allowed', '/');
+      return $response;
+    }
+    throw new NotFoundHttpException();
+  }
+
+}