Move the externalLinkTarget and externalLinkRel options to PDFLinkService options

This removes the `PDFJS.externalLinkTarget`/`PDFJS.externalLinkRel` dependency from the viewer components, but please note that as a *temporary* solution the default viewer still uses it.

web/app.js

@@ -22,7 +22,7 @@ import {
 } from './ui_utils';
 import {
   build, createBlob, getDocument, getFilenameFromUrl, InvalidPDFException,
-  MissingPDFException, OPS, PDFJS, PDFWorker, shadow,
+  LinkTarget, MissingPDFException, OPS, PDFJS, PDFWorker, shadow,
   UnexpectedResponseException, UNSUPPORTED_FEATURES, version
 } from 'pdfjs-lib';
 import { CursorTool, PDFCursorTools } from './pdf_cursor_tools';
@@ -184,10 +184,11 @@ let PDFViewerApplication = {
         this.eventBus.dispatch('localized');
       });
 
-      if (this.isViewerEmbedded && !PDFJS.isExternalLinkTargetSet()) {
+      if (this.isViewerEmbedded &&
+          PDFJS.externalLinkTarget === LinkTarget.NONE) {
         // Prevent external links from "replacing" the viewer,
         // when it's embedded in e.g. an iframe or an object.
-        PDFJS.externalLinkTarget = PDFJS.LinkTarget.TOP;
+        PDFJS.externalLinkTarget = LinkTarget.TOP;
       }
 
       this.initialized = true;
@@ -250,7 +251,7 @@ let PDFViewerApplication = {
         PDFJS.useOnlyCssZoom = value;
       }),
       preferences.get('externalLinkTarget').then(function resolved(value) {
-        if (PDFJS.isExternalLinkTargetSet()) {
+        if (PDFJS.externalLinkTarget !== LinkTarget.NONE) {
           return;
         }
         PDFJS.externalLinkTarget = value;
@@ -378,6 +379,8 @@ let PDFViewerApplication = {
 
       let pdfLinkService = new PDFLinkService({
         eventBus,
+        externalLinkTarget: PDFJS.externalLinkTarget,
+        externalLinkRel: PDFJS.externalLinkRel,
       });
       this.pdfLinkService = pdfLinkService;
 

web/pdf_link_service.js

@@ -19,6 +19,11 @@ import { parseQueryString } from './ui_utils';
 /**
  * @typedef {Object} PDFLinkServiceOptions
  * @property {EventBus} eventBus - The application event bus.
+ * @property {number} externalLinkTarget - (optional) Specifies the `target`
+ *   attribute for external links. Must use one of the values from {LinkTarget}.
+ *   Defaults to using no target.
+ * @property {string} externalLinkRel - (optional) Specifies the `rel` attribute
+ *   for external links. Defaults to stripping the referrer.
  */
 
 /**
@@ -30,8 +35,12 @@ class PDFLinkService {
   /**
    * @param {PDFLinkServiceOptions} options
    */
-  constructor({ eventBus, } = {}) {
+  constructor({ eventBus, externalLinkTarget = null,
+                externalLinkRel = null, } = {}) {
     this.eventBus = eventBus || getGlobalEventBus();
+    this.externalLinkTarget = externalLinkTarget;
+    this.externalLinkRel = externalLinkRel;
+
     this.baseUrl = null;
     this.pdfDocument = null;
     this.pdfViewer = null;
@@ -409,6 +418,11 @@ function isValidExplicitDestination(dest) {
 }
 
 class SimpleLinkService {
+  constructor() {
+    this.externalLinkTarget = null;
+    this.externalLinkRel = null;
+  }
+
   /**
    * @returns {number}
    */

web/pdf_outline_viewer.js

@@ -13,9 +13,7 @@
  * limitations under the License.
  */
 
-import {
-  addLinkAttributes, PDFJS, removeNullCharacters
-} from 'pdfjs-lib';
+import { addLinkAttributes, LinkTarget, removeNullCharacters } from 'pdfjs-lib';
 
 const DEFAULT_TITLE = '\u2013';
 
@@ -68,20 +66,22 @@ class PDFOutlineViewer {
   /**
    * @private
    */
-  _bindLink(element, item) {
-    if (item.url) {
+  _bindLink(element, { url, newWindow, dest, }) {
+    let { linkService, } = this;
+
+    if (url) {
       addLinkAttributes(element, {
-        url: item.url,
-        target: (item.newWindow ? PDFJS.LinkTarget.BLANK : undefined),
+        url,
+        target: (newWindow ? LinkTarget.BLANK : linkService.externalLinkTarget),
+        rel: linkService.externalLinkRel,
       });
       return;
     }
-    let destination = item.dest;
 
-    element.href = this.linkService.getDestinationHash(destination);
+    element.href = this.linkService.getDestinationHash(dest);
     element.onclick = () => {
-      if (destination) {
-        this.linkService.navigateTo(destination);
+      if (dest) {
+        this.linkService.navigateTo(dest);
       }
       return false;
     };
@@ -90,12 +90,12 @@ class PDFOutlineViewer {
   /**
    * @private
    */
-  _setStyles(element, item) {
+  _setStyles(element, { bold, italic, }) {
     let styleStr = '';
-    if (item.bold) {
+    if (bold) {
       styleStr += 'font-weight: bold;';
     }
-    if (item.italic) {
+    if (italic) {
       styleStr += 'font-style: italic;';
     }