Merge pull request #6058 from prlanzarin/screenshare-fix-presenter-switch

Fix screenshare edge case with presenter switch

bigbluebutton-html5/client/compatibility/kurento-extension.js

@@ -108,15 +108,11 @@ KurentoManager.prototype.exitScreenShare = function () {
     this.kurentoScreenshare.dispose();
     this.kurentoScreenshare = null;
   }
-
-  if (typeof this.kurentoVideo !== 'undefined' && this.kurentoVideo) {
-    this.exitVideo();
-  }
 };
 
 KurentoManager.prototype.exitVideo = function () {
+  try {
     if (typeof this.kurentoVideo !== 'undefined' && this.kurentoVideo) {
-
       if(this.kurentoVideo.webRtcPeer) {
         this.kurentoVideo.webRtcPeer.peerConnection.oniceconnectionstatechange = null;
       }
@@ -137,6 +133,13 @@ KurentoManager.prototype.exitVideo = function () {
       this.kurentoVideo.dispose();
       this.kurentoVideo = null;
     }
+  }
+  catch (err) {
+    if (this.kurentoVideo) {
+      this.kurentoVideo.dispose();
+      this.kurentoVideo = null;
+    }
+  }
 };
 
 KurentoManager.prototype.exitAudio = function () {

labs/bbb-webrtc-sfu/lib/base/BaseManager.js

@@ -137,7 +137,7 @@ module.exports = class BaseManager {
   }
 
   _handleError (logPrefix, connectionId, streamId, role, error) {
-    if (this._validateErrorMessage(error)) {
+    if (error && this._validateErrorMessage(error)) {
       return error;
     }
 

labs/bbb-webrtc-sfu/lib/bbb/messages/Constants.js

@@ -69,10 +69,9 @@ const config = require('config');
         STOP_TRANSCODER_RESP_2x: "StopTranscoderSysRespMsg",
         GLOBAL_AUDIO_CONNECTED_2x: "UserConnectedToGlobalAudioMsg",
         GLOBAL_AUDIO_DISCONNECTED_2x: "UserDisconnectedFromGlobalAudioMsg",
-        // TODO: Check if this is the correct message in BBB 2.x
         DICONNECT_ALL_USERS_2x: "DisconnectAllClientsSysMsg",
-
         USER_CAM_BROADCAST_STOPPED_2x: "UserBroadcastCamStopMsg",
+        PRESENTER_ASSIGNED_2x: "PresenterAssignedEvtMsg",
 
         STREAM_IS_RECORDED: "StreamIsRecordedMsg",
 

labs/bbb-webrtc-sfu/lib/bbb/pubsub/bbb-gw.js

@@ -105,6 +105,11 @@ module.exports = class BigBlueButtonGW extends EventEmitter {
           payload[C.MEETING_ID_2x] = header[C.MEETING_ID_2x];
           this.emit(C.DICONNECT_ALL_USERS_2x, payload);
           break;
+        case C.PRESENTER_ASSIGNED_2x:
+          meetingId = header[C.MEETING_ID_2x];
+          payload[C.MEETING_ID_2x] = meetingId;
+          this.emit(C.PRESENTER_ASSIGNED_2x+meetingId, payload);
+          break;
         default:
           this.emit(C.GATEWAY_MESSAGE, msg);
       }

labs/bbb-webrtc-sfu/lib/connection-manager/WebsocketConnectionManager.js

@@ -29,9 +29,17 @@ module.exports = class WebsocketConnectionManager {
     const connectionId = data? data.connectionId : null;
     const ws = this.webSockets[connectionId];
     if (ws) {
+      if (data.id === 'close') {
+        try {
+          ws.close();
+        } catch (err) {
+          Logger.warn('[WebsocketConnectionManager] Error on closing WS for', connectionId,  err)
+        }
+      } else {
         this.sendMessage(ws, data);
       }
     }
+  }
 
   _onNewConnection (ws) {
     ws.id = connectionIDCounter++;

labs/bbb-webrtc-sfu/lib/screenshare/ScreenshareManager.js

@@ -70,6 +70,19 @@ module.exports = class ScreenshareManager extends BaseManager {
             this._stopSession(sessionId);
           });
 
+          // listen for presenter change to avoid inconsistent states on reconnection
+          if (role === C.SEND_ROLE) {
+            this._bbbGW.once(C.PRESENTER_ASSIGNED_2x+message.internalMeetingId, async (payload) => {
+              Logger.info(this._logPrefix, "Presenter changed, forcibly closing screensharing session at", message.internalMeetingId);
+              await this.closeSession(session, connectionId, role, sessionId);
+              this._bbbGW.publish(JSON.stringify({
+                connectionId: connectionId,
+                type: C.SCREENSHARE_APP,
+                id : 'close',
+              }), C.FROM_SCREENSHARE);
+            });
+          }
+
           Logger.info(this._logPrefix, "Sending startResponse to peer", sessionId, "for connection", session._id);
         }
         catch (error) {
@@ -101,17 +114,7 @@ module.exports = class ScreenshareManager extends BaseManager {
 
       case 'close':
         Logger.info(this._logPrefix, 'Connection ' + connectionId + ' closed');
-
+        this.closeSession(session, connectionId, role, sessionId);
-        if (session && session.constructor == Screenshare) {
-          if (role === C.SEND_ROLE && session) {
-            Logger.info(this._logPrefix, "Stopping presenter " + sessionId);
-            this._stopSession(sessionId);
-          }
-          if (role === C.RECV_ROLE && session) {
-            Logger.info(this._logPrefix, "Stopping viewer " + sessionId);
-            session.stopViewer(message.connectionId);
-          }
-        }
         break;
 
       default:
@@ -122,4 +125,18 @@ module.exports = class ScreenshareManager extends BaseManager {
         break;
     }
   }
+
+  async closeSession (session, connectionId, role, sessionId) {
+    if (session && session.constructor == Screenshare) {
+      if (role === C.SEND_ROLE && session) {
+        Logger.info(this._logPrefix, "Stopping presenter " + sessionId);
+        await this._stopSession(sessionId);
+        return;
+      }
+      if (role === C.RECV_ROLE && session) {
+        Logger.info(this._logPrefix, "Stopping viewer " + sessionId);
+        await session.stopViewer(connectionId);
+      }
+    }
+  }
 };

labs/bbb-webrtc-sfu/lib/screenshare/screenshare.js

@@ -227,6 +227,8 @@ module.exports = class Screenshare extends BaseProvider {
 
   start (sessionId, connectionId, sdpOffer, userId, role) {
     return new Promise(async (resolve, reject) => {
+      this._status = C.MEDIA_STARTING;
+
       // Forces H264 with a possible preferred profile
       if (FORCE_H264) {
         sdpOffer = h264_sdp.transform(sdpOffer, PREFERRED_H264_PROFILE);
@@ -347,6 +349,9 @@ module.exports = class Screenshare extends BaseProvider {
   stop () {
     return new Promise(async (resolve, reject) => {
       try {
+        if (this._status === C.MEDIA_STOPPED) {
+          return resolve();
+        }
         Logger.info('[screnshare] Stopping and releasing endpoints for MCS user', this.mcsUserId);
         await this._stopScreensharing();
         this._status = C.MEDIA_STOPPED;