fix Settings sanitizer for initialTrackSelection based on id (Dash-Industry-Forum#4739)

* two unit tests for initial track selection based on @id

* fix to MediaPlayer related to initialTrackSelectrion based on id in settings

* small fix

* handling of empty strings

Author: stschr

src/streaming/MediaPlayer.js

@@ -2709,6 +2709,7 @@ function MediaPlayer() {
 
         function __sanitizeDescriptorType(name, val, defaultSchemeIdUri) {
             let out = {};
+            // For an empty string, let's unset the descriptor, i.e. return null
             if (val) {
                 if (val instanceof Array) {
                     throw ARRAY_NOT_SUPPORTED_ERROR;
@@ -2725,22 +2726,25 @@ function MediaPlayer() {
             return null;
         }
 
-        if (value.lang) {
+        if (value.id !== undefined) {
+            output.id = value.id;
+        }
+        if (value.lang !== undefined) {
             output.lang = value.lang;
         }
         if (!isNaN(value.index)) {
             output.index = value.index;
         }
-        if (value.viewpoint) {
+        if (value.viewpoint !== undefined) {
             output.viewpoint = __sanitizeDescriptorType('viewpoint', value.viewpoint, defaults.viewpoint);
         }
-        if (value.audioChannelConfiguration) {
+        if (value.audioChannelConfiguration !== undefined) {
             output.audioChannelConfiguration = __sanitizeDescriptorType('audioChannelConfiguration', value.audioChannelConfiguration, defaults.audioChannelConfiguration);
         }
-        if (value.role) {
+        if (value.role !== undefined) {
             output.role = __sanitizeDescriptorType('role', value.role, defaults.role);
         }
-        if (value.accessibility) {
+        if (value.accessibility !== undefined) {
             output.accessibility = __sanitizeDescriptorType('accessibility', value.accessibility, defaults.accessibility);
         }
 

test/unit/test/streaming/streaming.controllers.MediaController.js

@@ -384,6 +384,7 @@ describe('MediaController', function () {
             id: 'id'
         };
         const frTrack = {
+            id: 0,
             type: trackType,
             streamInfo: streamInfo,
             lang: 'fr',
@@ -393,6 +394,7 @@ describe('MediaController', function () {
             audioChannelConfiguration: [{ schemeIdUri: 'urn:mpeg:mpegB:cicp:ChannelConfiguration', value: '2' }]
         };
         const qtzTrack = {
+            id: 'qtz',
             type: trackType,
             streamInfo: streamInfo,
             lang: 'qtz',
@@ -402,6 +404,7 @@ describe('MediaController', function () {
             audioChannelConfiguration: [{ schemeIdUri: 'urn:mpeg:mpegB:cicp:ChannelConfiguration', value: '2' }]
         };
         const enTrack = {
+            id: 2,
             type: trackType,
             streamInfo: streamInfo,
             lang: 'en',
@@ -412,6 +415,7 @@ describe('MediaController', function () {
             selectionPriority: 5
         };
         const enADTrack = {
+            id: 3,
             type: trackType,
             streamInfo: streamInfo,
             lang: 'en',
@@ -422,6 +426,7 @@ describe('MediaController', function () {
             selectionPriority: 3
         };
         const esTrack = {
+            id: 'esTrack',
             type: trackType,
             streamInfo: streamInfo,
             lang: 'es',
@@ -456,6 +461,46 @@ describe('MediaController', function () {
 
         });
 
+        it('should check initial media settings to choose initial track via integer-id', function () {
+            mediaController.addTrack(qtzTrack);
+            mediaController.addTrack(esTrack);
+            mediaController.addTrack(frTrack);
+            mediaController.addTrack(enTrack);
+            mediaController.addTrack(enADTrack);
+
+            let trackList = mediaController.getTracksFor(trackType, streamInfo.id);
+            expect(trackList).to.have.lengthOf(5);
+
+            mediaController.setInitialSettings(trackType, {
+                id: 2,
+                lang: 'es'
+            });
+            mediaController.setInitialMediaSettingsForType(trackType, streamInfo);
+
+            let currentTrack = mediaController.getCurrentTrackFor(trackType, streamInfo.id);
+            expect(objectUtils.areEqual(currentTrack, enTrack)).to.be.true;
+        });
+
+        it('should check initial media settings to choose initial track via string-id', function () {
+            mediaController.addTrack(qtzTrack);
+            mediaController.addTrack(esTrack);
+            mediaController.addTrack(frTrack);
+            mediaController.addTrack(enTrack);
+            mediaController.addTrack(enADTrack);
+            
+            let trackList = mediaController.getTracksFor(trackType, streamInfo.id);
+            expect(trackList).to.have.lengthOf(5);
+            
+            mediaController.setInitialSettings(trackType, {
+                id: 'esTrack',
+                lang: 'en'
+            });
+            mediaController.setInitialMediaSettingsForType(trackType, streamInfo);
+            
+            let currentTrack = mediaController.getCurrentTrackFor(trackType, streamInfo.id);
+            expect(objectUtils.areEqual(currentTrack, esTrack)).to.be.true;
+        });
+
         it('should check initial media settings to choose initial track with 639-2 3-letter code', function () {
             mediaController.addTrack(qtzTrack);
             mediaController.addTrack(frTrack);