feat: add pliOnConnect feature flag to force PLIs on new subscriber c…

…onnections Disabled by default
bigbluebutton · Apr 4, 2023 · 541d3be · 541d3be
1 parent 72cec88
commit 541d3be
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Showing 3 changed files with 61 additions and 25 deletions.
diff --git a/config/default.example.yml b/config/default.example.yml
@@ -69,7 +69,13 @@ audioIceRestartEnabled: false
 # WebRTC should be used for environments where the bridge is between external
 # servers AND when mediasoup is being used
 fsBridgeMode: 'RTP'
-
+# pliOnConnect: whether to send a PLI when a new subscriber joins
+#  amount: max amount of PLIs to send. If 0, it won't send any PLIs (default)
+#  interval: interval between PLIs (in ms)
+#  (e.g.: amount: 3, interval: 2000 => send 3 PLIs every 2 seconds)
+pliOnConnect:
+  amount: 0
+  interval: 2000
 # Whether to record screen raw files
 recordScreenSharing: true
 # Whether to record camera raw files

diff --git a/lib/screenshare/screenshare.js b/lib/screenshare/screenshare.js
@@ -41,10 +41,13 @@ const GENERATE_TS_ON_RECORDING_EVT = config.has('recordingGenerateTsOnRecEvt')
 const RECORDING_PLI_ON_NOT_FLOWING = config.has('recordingPliOnNotFlowing')
   ? config.get('recordingPliOnNotFlowing')
   : false;
+const PLI_ON_CONNECT = config.has('pliOnConnect')
+  ? config.get('pliOnConnect')
+  : null;
 
 const LOG_PREFIX = "[screenshare]";
-const PLI_SHOTS = 3;
-const PLI_FREQ = 2000;
+const REC_PLI_SHOTS = 3;
+const REC_PLI_FREQ = 2000;
 const REC_FLOW_TIMER = 500;
 
 module.exports = class Screenshare extends BaseProvider {
@@ -124,7 +127,6 @@ module.exports = class Screenshare extends BaseProvider {
       hgaPubMediaId: null, // ?: string (<T>)
     };
     this._pliInterval = null;
-    this._pliShots = 0;
 
     this._trackMCSEvents();
   }
@@ -452,7 +454,13 @@ module.exports = class Screenshare extends BaseProvider {
 
           if (RECORDING_PLI_ON_NOT_FLOWING && this.hgaRecordingSet.flowTracker == null) {
             this.hgaRecordingSet.flowTracker = setTimeout(() => {
-              this._pliSalvo(this.hgaRecordingSet.nativeSubMediaId);
+              this._pliSalvo(
+                this.hgaRecordingSet.nativeSubMediaId,
+                REC_PLI_SHOTS,
+                REC_PLI_FREQ, {
+                  fastStart: true,
+                },
+              );
             }, REC_FLOW_TIMER);
           }
         } else if (details === 'FLOWING') {
@@ -485,32 +493,35 @@ module.exports = class Screenshare extends BaseProvider {
     });
   }
 
-  _pliSalvo (endpoint) {
+  _pliSalvo (endpoint, shots, freq, { fastStart = false } = {}) {
     if (this._pliInterval || endpoint == null) return;
+    let iterations = 0;
 
     Logger.warn(
       `Firing recording PLI salvo: ${endpoint}`,
       this._getFullPresenterLogMetadata(this._connectionId)
     );
-    this._requestKeyframe(endpoint);
-    this._pliShots++
+
+    if (fastStart) {
+      this._requestKeyframe(endpoint);
+      iterations++;
+    }
+
     this._pliInterval = setInterval(() => {
-      if (this._pliShots >= PLI_SHOTS) {
+      if (iterations >= shots) {
         this._clearPliSalvo();
       } else {
-        this._pliShots++;
+        iterations++;
         this._requestKeyframe(endpoint);
       }
-    }, PLI_FREQ);
+    }, freq);
   }
 
   _clearPliSalvo () {
     if (this._pliInterval) {
       clearInterval(this._pliInterval);
       this._pliInterval = null;
     }
-
-    this._pliShots = 0;
   }
 
   async _stopHGARecordingSet () {
@@ -893,6 +904,10 @@ module.exports = class Screenshare extends BaseProvider {
       Logger.info(`Viewer WebRTC stream was successfully created`,
         this._getFullViewerLogMetadata(connectionId));
 
+      if (PLI_ON_CONNECT && PLI_ON_CONNECT.amount > 0) {
+        this._pliSalvo(mediaId, PLI_ON_CONNECT.amount, PLI_ON_CONNECT.interval);
+      }
+
       return answer;
     } catch (error) {
       Logger.error(`Viewer subscribe failed for ${userId} due to ${error.message}`,

diff --git a/lib/video/video.js b/lib/video/video.js
@@ -26,10 +26,13 @@ const GENERATE_TS_ON_RECORDING_EVT = config.has('recordingGenerateTsOnRecEvt')
 const RECORDING_PLI_ON_NOT_FLOWING = config.has('recordingPliOnNotFlowing')
   ? config.get('recordingPliOnNotFlowing')
   : false;
+const PLI_ON_CONNECT = config.has('pliOnConnect')
+  ? config.get('pliOnConnect')
+  : null;
 
 const LOG_PREFIX = "[video]";
-const PLI_SHOTS = 3;
-const PLI_FREQ = 2000;
+const REC_PLI_SHOTS = 3;
+const REC_PLI_FREQ = 2000;
 const REC_FLOW_TIMER = 500;
 
 let sources = {};
@@ -79,7 +82,6 @@ module.exports = class Video extends BaseProvider {
       hgaPubMediaId: null, // ?: string (<T>)
     };
     this._pliInterval = null;
-    this._pliShots = 0;
 
     this._bindEventHandlers();
     this._trackBigBlueButtonEvents();
@@ -386,7 +388,13 @@ module.exports = class Video extends BaseProvider {
 
           if (RECORDING_PLI_ON_NOT_FLOWING && this.hgaRecordingSet.flowTracker == null) {
             this.hgaRecordingSet.flowTracker = setTimeout(() => {
-              this._pliSalvo(this.hgaRecordingSet.nativeSubMediaId);
+              this._pliSalvo(
+                this.hgaRecordingSet.nativeSubMediaId,
+                REC_PLI_SHOTS,
+                REC_PLI_FREQ, {
+                  fastStart: true,
+                },
+              );
             }, REC_FLOW_TIMER);
           }
         } else if (details === 'FLOWING') {
@@ -495,30 +503,32 @@ module.exports = class Video extends BaseProvider {
     });
   }
 
-  _pliSalvo (endpoint) {
+  _pliSalvo (endpoint, shots, freq, { fastStart = false } = {}) {
     if (this._pliInterval || endpoint == null) return;
+    let iterations = 0;
 
     Logger.warn(`Firing recording PLI salvo: ${endpoint}`, this._getLogMetadata());
 
-    this._requestKeyframe(endpoint);
-    this._pliShots++
+    if (fastStart) {
+      this._requestKeyframe(endpoint);
+      iterations++;
+    }
+
     this._pliInterval = setInterval(() => {
-      if (this._pliShots >= PLI_SHOTS) {
+      if (iterations >= shots) {
         this._clearPliSalvo();
       } else {
-        this._pliShots++;
+        iterations++;
         this._requestKeyframe(endpoint);
       }
-    }, PLI_FREQ);
+    }, freq);
   }
 
   _clearPliSalvo () {
     if (this._pliInterval) {
       clearInterval(this._pliInterval);
       this._pliInterval = null;
     }
-
-    this._pliShots = 0;
   }
 
   shouldRecord () {
@@ -850,6 +860,11 @@ module.exports = class Video extends BaseProvider {
     const stream = Video.getSource(this.id);
     const { mediaId, answer } = await this.mcs.subscribe(this.userId, stream, C.WEBRTC, options);
     this.mediaId = mediaId;
+
+    if (PLI_ON_CONNECT && PLI_ON_CONNECT.amount > 0) {
+      this._pliSalvo(this.mediaId, PLI_ON_CONNECT.amount, PLI_ON_CONNECT.interval);
+    }
+
     return answer;
   }