Use PDF URL instead of URN when not a file:// URI

Which will then be used as the `target.source` when creating an
annotation.

h/static/scripts/annotator/plugin/pdf-metadata.js

@@ -27,7 +27,11 @@ function PDFMetadata(app) {
  */
 PDFMetadata.prototype.getUri = function () {
   return this._loaded.then(function (app) {
-    return fingerprintToURN(app.documentFingerprint);
+    var uri = getPDFURL(app);
+    if (!uri) {
+      uri = fingerprintToURN(app.documentFingerprint);
+    }
+    return uri;
   });
 };
 
@@ -52,11 +56,9 @@ PDFMetadata.prototype.getMetadata = function () {
       {href: fingerprintToURN(app.documentFingerprint)}
     ];
 
-    // Local file:// URLs should not be saved in document metadata.
-    // Entries in document.link should be URIs. In the case of
-    // local files, omit the URL.
-    if (app.url.indexOf('file://') !== 0) {
-      link.push({href: app.url});
+    var url = getPDFURL(app);
+    if (url) {
+      link.push({href: url});
     }
 
     return {
@@ -71,4 +73,15 @@ function fingerprintToURN(fingerprint) {
   return 'urn:x-pdf:' + String(fingerprint);
 }
 
+function getPDFURL(app) {
+  // Local file:// URLs should not be saved in document metadata.
+  // Entries in document.link should be URIs. In the case of
+  // local files, omit the URL.
+  if (app.url.indexOf('file://') !== 0) {
+    return app.url;
+  }
+
+  return null;
+}
+
 module.exports = PDFMetadata;

h/static/scripts/annotator/plugin/test/pdf-metadata-test.js

@@ -9,19 +9,23 @@ describe('pdf-metadata', function () {
 
     var event = document.createEvent('Event');
     event.initEvent('documentload', false, false);
+    fakeApp.url = 'http://fake.com';
     fakeApp.documentFingerprint = 'fakeFingerprint';
     window.dispatchEvent(event);
 
     return pdfMetadata.getUri().then(function (uri) {
-      assert.equal(uri, 'urn:x-pdf:fakeFingerprint');
+      assert.equal(uri, 'http://fake.com');
     });
   });
 
   it('does not wait for the PDF to load if it has already loaded', function () {
-    var fakePDFViewerApplication = {documentFingerprint: 'fakeFingerprint'};
+    var fakePDFViewerApplication = {
+      url: 'http://fake.com',
+      documentFingerprint: 'fakeFingerprint',
+    };
     var pdfMetadata = new PDFMetadata(fakePDFViewerApplication);
     return pdfMetadata.getUri().then(function (uri) {
-      assert.equal(uri, 'urn:x-pdf:fakeFingerprint');
+      assert.equal(uri, 'http://fake.com');
     });
   });
 
@@ -37,7 +41,7 @@ describe('pdf-metadata', function () {
           'dc:title': 'fakeTitle',
         }
       },
-      url: 'fakeUrl',
+      url: 'http://fake.com',
     };
 
     beforeEach(function () {
@@ -45,7 +49,19 @@ describe('pdf-metadata', function () {
     });
 
     describe('#getUri', function () {
-      it('returns the URN-ified document fingerprint as its URI', function () {
+      it('returns the non-file URI', function() {
+        return pdfMetadata.getUri().then(function (uri) {
+          assert.equal(uri, 'http://fake.com');
+        });
+      });
+
+      it('returns the fingerprint as a URN when the PDF URL is a local file', function () {
+        var fakePDFViewerApplication = {
+          url: 'file:///test.pdf',
+          documentFingerprint: 'fakeFingerprint',
+        };
+        var pdfMetadata = new PDFMetadata(fakePDFViewerApplication);
+
         return pdfMetadata.getUri().then(function (uri) {
           assert.equal(uri, 'urn:x-pdf:fakeFingerprint');
         });
@@ -88,7 +104,7 @@ describe('pdf-metadata', function () {
         var pdfMetadata;
         var fakePDFViewerApplication = {
           documentFingerprint: 'fakeFingerprint',
-          url: 'file://fakeUrl',
+          url: 'file://fake.pdf',
         };
         var expectedMetadata = {
           link: [{href: 'urn:x-pdf:' + fakePDFViewerApplication.documentFingerprint}],