Close media key sessions and clear media keys when media detached

src/controller/eme-controller.ts

@@ -522,10 +522,27 @@ class EMEController extends EventHandler {
   }
 
   onMediaDetached () {
-    if (this._media) {
-      this._media.removeEventListener('encrypted', this._onMediaEncrypted);
-      this._media = null; // release reference
+    const media = this._media;
+    const mediaKeysList = this._mediaKeysList;
+    if (!media) {
+      return;
     }
+    media.removeEventListener('encrypted', this._onMediaEncrypted);
+    this._media = null;
+    this._mediaKeysList = [];
+    // Close all sessions and remove media keys from the video element.
+    Promise.all(mediaKeysList.map((mediaKeysListItem) => {
+      if (mediaKeysListItem.mediaKeysSession) {
+          return mediaKeysListItem.mediaKeysSession.close().catch(() => {
+            // Ignore errors when closing the sessions. Closing a session that
+            // generated no key requests will throw an error.
+          });
+      }
+    })).then(() => {
+      return media.setMediaKeys(null);
+    }).catch(() => {
+      // Ignore any failures while removing media keys from the video element.
+    });
   }
 
   // TODO: Use manifest types here when they are defined

tests/unit/controller/eme-controller.js

@@ -9,6 +9,7 @@ const MediaMock = function () {
   let media = new EventEmitter();
   media.setMediaKeys = sinon.spy();
   media.addEventListener = media.addListener.bind(media);
+  media.removeEventListener = media.removeListener.bind(media);
   return media;
 };
 
@@ -104,4 +105,33 @@ describe('EMEController', function () {
       done();
     }, 0);
   });
+
+  it('should close all media key sessions and remove media keys when media is detached', function (done) {
+    let reqMediaKsAccessSpy = sinon.spy(function () {
+      return Promise.resolve({
+        // Media-keys mock
+      });
+    });
+    let keySessionCloseSpy = sinon.spy(() => Promise.resolve());
+
+    setupEach({
+      emeEnabled: true,
+      requestMediaKeySystemAccessFunc: reqMediaKsAccessSpy
+    });
+
+    emeController.onMediaAttached({ media });
+    emeController._mediaKeysList = [{
+      mediaKeysSession: {
+        close: keySessionCloseSpy
+      }
+    }];
+    emeController.onMediaDetached();
+
+    setTimeout(function () {
+      expect(keySessionCloseSpy.callCount).to.equal(1);
+      expect(emeController._mediaKeysList.length).to.equal(0);
+      expect(media.setMediaKeys.calledWith(null)).to.be.true;
+      done();
+    }, 0);
+  });
 });