Merge pull request #5952 from Snuffleupagus/api-externalLinkTarget

[api-minor] Add an option to PDFJS for specifying the |target| attribute of external links (bug 976541)

src/display/annotation_helper.js

@@ -15,7 +15,7 @@
  * limitations under the License.
  */
 /* globals PDFJS, Util, AnnotationType, AnnotationBorderStyleType, warn,
-           CustomStyle */
+           CustomStyle, isExternalLinkTargetSet, LinkTargetStringMap */
 
 'use strict';
 
@@ -261,8 +261,9 @@ var AnnotationUtils = (function AnnotationUtilsClosure() {
 
     var link = document.createElement('a');
     link.href = link.title = item.url || '';
-    if (item.url && PDFJS.openExternalLinksInNewWindow) {
+
-      link.target = '_blank';
+    if (item.url && isExternalLinkTargetSet()) {
+      link.target = LinkTargetStringMap[PDFJS.externalLinkTarget];
     }
 
     container.appendChild(link);

src/display/api.js

@@ -169,14 +169,27 @@ PDFJS.maxCanvasPixels = (PDFJS.maxCanvasPixels === undefined ?
                          16777216 : PDFJS.maxCanvasPixels);
 
 /**
- * Opens external links in a new window if enabled. The default behavior opens
+ * (Deprecated) Opens external links in a new window if enabled.
- * external links in the PDF.js window.
+ * The default behavior opens external links in the PDF.js window.
  * @var {boolean}
  */
 PDFJS.openExternalLinksInNewWindow = (
   PDFJS.openExternalLinksInNewWindow === undefined ?
     false : PDFJS.openExternalLinksInNewWindow);
 
+/**
+ * Specifies the |target| attribute for external links.
+ * The constants from PDFJS.LinkTarget should be used:
+ *  - NONE [default]
+ *  - SELF
+ *  - BLANK
+ *  - PARENT
+ *  - TOP
+ * @var {number}
+ */
+PDFJS.externalLinkTarget = (PDFJS.externalLinkTarget === undefined ?
+                            PDFJS.LinkTarget.NONE : PDFJS.externalLinkTarget);
+
 /**
   * Determines if we can eval strings as JS. Primarily used to improve
   * performance for font rendering.

src/shared/util.js

@@ -328,6 +328,49 @@ function shadow(obj, prop, value) {
 }
 PDFJS.shadow = shadow;
 
+var LinkTarget = PDFJS.LinkTarget = {
+  NONE: 0, // Default value.
+  SELF: 1,
+  BLANK: 2,
+  PARENT: 3,
+  TOP: 4,
+};
+var LinkTargetStringMap = [
+  '',
+  '_self',
+  '_blank',
+  '_parent',
+  '_top'
+];
+
+function isExternalLinkTargetSet() {
+//#if GENERIC
+  if (PDFJS.openExternalLinksInNewWindow) {
+    warn('PDFJS.openExternalLinksInNewWindow is deprecated, ' +
+         'use PDFJS.externalLinkTarget instead.');
+    if (PDFJS.externalLinkTarget === LinkTarget.NONE) {
+      PDFJS.externalLinkTarget = LinkTarget.BLANK;
+    }
+    // Reset the deprecated parameter, to suppress further warnings.
+    PDFJS.openExternalLinksInNewWindow = false;
+  }
+//#endif
+  switch (PDFJS.externalLinkTarget) {
+    case LinkTarget.NONE:
+      return false;
+    case LinkTarget.SELF:
+    case LinkTarget.BLANK:
+    case LinkTarget.PARENT:
+    case LinkTarget.TOP:
+      return true;
+  }
+  warn('PDFJS.externalLinkTarget is invalid: ' + PDFJS.externalLinkTarget);
+  // Reset the external link target, to suppress further warnings.
+  PDFJS.externalLinkTarget = LinkTarget.NONE;
+  return false;
+}
+PDFJS.isExternalLinkTargetSet = isExternalLinkTargetSet;
+
 var PasswordResponses = PDFJS.PasswordResponses = {
   NEED_PASSWORD: 1,
   INCORRECT_PASSWORD: 2

test/unit/util_spec.js

@@ -1,7 +1,7 @@
 /* -*- Mode: Java; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
 /* vim: set shiftwidth=2 tabstop=2 autoindent cindent expandtab: */
-/* globals expect, it, describe, combineUrl, Dict, isDict, Name,
+/* globals expect, it, describe, combineUrl, Dict, isDict, Name, PDFJS,
-           stringToPDFString */
+           stringToPDFString, isExternalLinkTargetSet, LinkTarget */
 
 'use strict';
 
@@ -99,4 +99,32 @@ describe('util', function() {
       expect(stringToPDFString(str2)).toEqual('');
     });
   });
+
+  describe('isExternalLinkTargetSet', function() {
+    // Save the current state, to avoid interfering with other tests.
+    var previousExternalLinkTarget = PDFJS.externalLinkTarget;
+
+    it('handles the predefined LinkTargets', function() {
+      for (var key in LinkTarget) {
+        var linkTarget = LinkTarget[key];
+        PDFJS.externalLinkTarget = linkTarget;
+
+        expect(isExternalLinkTargetSet()).toEqual(!!linkTarget);
+      }
+    });
+
+    it('handles incorrect LinkTargets', function() {
+      var targets = [true, '', false, -1, '_blank', null];
+
+      for (var i = 0, ii = targets.length; i < ii; i++) {
+        var linkTarget = targets[i];
+        PDFJS.externalLinkTarget = linkTarget;
+
+        expect(isExternalLinkTargetSet()).toEqual(false);
+      }
+    });
+
+    // Reset the state.
+    PDFJS.externalLinkTarget = previousExternalLinkTarget;
+  });
 });

web/default_preferences.js

@@ -32,5 +32,6 @@ var DEFAULT_PREFERENCES = {
   disableAutoFetch: false,
   disableFontFace: false,
   disableTextLayer: false,
-  useOnlyCssZoom: false
+  useOnlyCssZoom: false,
+  externalLinkTarget: 0,
 };

web/viewer.js

@@ -288,12 +288,24 @@ var PDFViewerApplication = {
       }),
       Preferences.get('useOnlyCssZoom').then(function resolved(value) {
         PDFJS.useOnlyCssZoom = value;
-      })
+      }),
+      Preferences.get('externalLinkTarget').then(function resolved(value) {
+        if (PDFJS.isExternalLinkTargetSet()) {
+          return;
+        }
+        PDFJS.externalLinkTarget = value;
+      }),
       // TODO move more preferences and other async stuff here
     ]).catch(function (reason) { });
 
     return initializedPromise.then(function () {
-      PDFViewerApplication.initialized = true;
+      if (self.isViewerEmbedded && !PDFJS.isExternalLinkTargetSet()) {
+        // Prevent external links from "replacing" the viewer,
+        // when it's embedded in e.g. an iframe or an object.
+        PDFJS.externalLinkTarget = PDFJS.LinkTarget.TOP;
+      }
+
+      self.initialized = true;
     });
   },