independent tracks for users & stream switching.

internal/capture/manager.go

@@ -176,43 +176,3 @@ func (manager *CaptureManagerCtx) Video(videoID string) (types.StreamManager, bo
 func (manager *CaptureManagerCtx) VideoIDs() []string {
 	return manager.videoIDs
 }
-
-func (manager *CaptureManagerCtx) StartStream() {
-	manager.mu.Lock()
-	defer manager.mu.Unlock()
-
-	manager.logger.Info().Msgf("starting stream pipelines")
-
-	for _, video := range manager.videos {
-		if err := video.Start(); err != nil {
-			manager.logger.Panic().Err(err).Msg("unable to start video pipeline")
-		}
-	}
-
-	if err := manager.audio.Start(); err != nil {
-		manager.logger.Panic().Err(err).Msg("unable to start audio pipeline")
-	}
-
-	manager.streaming = true
-}
-
-func (manager *CaptureManagerCtx) StopStream() {
-	manager.mu.Lock()
-	defer manager.mu.Unlock()
-
-	manager.logger.Info().Msgf("stopping stream pipelines")
-
-	for _, video := range manager.videos {
-		video.Stop()
-	}
-
-	manager.audio.Stop()
-	manager.streaming = false
-}
-
-func (manager *CaptureManagerCtx) Streaming() bool {
-	manager.mu.Lock()
-	defer manager.mu.Unlock()
-
-	return manager.streaming
-}

internal/capture/stream.go

@@ -92,6 +92,13 @@ func (manager *StreamManagerCtx) RemoveListener(listener *func(sample types.Samp
 	}
 }
 
+func (manager *StreamManagerCtx) ListenersCount() int {
+	manager.emitMu.Lock()
+	defer manager.emitMu.Unlock()
+
+	return len(manager.listeners)
+}
+
 func (manager *StreamManagerCtx) Start() error {
 	manager.mu.Lock()
 	defer manager.mu.Unlock()

internal/types/capture.go

@@ -23,8 +23,10 @@ type ScreencastManager interface {
 
 type StreamManager interface {
 	Codec() codec.RTPCodec
+
 	AddListener(listener *func(sample Sample))
 	RemoveListener(listener *func(sample Sample))
+	ListenersCount() int
 
 	Start() error
 	Stop()
@@ -40,8 +42,4 @@ type CaptureManager interface {
 	Audio() StreamManager
 	Video(videoID string) (StreamManager, bool)
 	VideoIDs() []string
-
-	StartStream()
-	StopStream()
-	Streaming() bool
 }

internal/webrtc/manager.go

@@ -29,7 +29,6 @@ func New(desktop types.DesktopManager, capture types.CaptureManager, config *con
 
 type WebRTCManagerCtx struct {
 	logger          zerolog.Logger
-	videoTracks     map[string]*webrtc.TrackLocalStaticSample
 	audioTrack      *webrtc.TrackLocalStaticSample
 	unsubscribe     []func()
 	defaultVideoID  string
@@ -60,36 +59,6 @@ func (manager *WebRTCManagerCtx) Start() {
 		audio.RemoveListener(&listener)
 	})
 
-	videoIDs := manager.capture.VideoIDs()
-	manager.videoTracks = map[string]*webrtc.TrackLocalStaticSample{}
-	for _, videoID := range videoIDs {
-		videoID := videoID
-
-		video, ok := manager.capture.Video(videoID)
-		if !ok {
-			manager.logger.Warn().Str("videoID", videoID).Msg("video stream not found, skipping")
-			continue
-		}
-
-		track, err := webrtc.NewTrackLocalStaticSample(video.Codec().Capability, "video", "stream")
-		if err != nil {
-			manager.logger.Panic().Err(err).Str("videoID", videoID).Msg("unable to create video track")
-		}
-
-		listener := func(sample types.Sample) {
-			if err := track.WriteSample(media.Sample(sample)); err != nil && err != io.ErrClosedPipe {
-				manager.logger.Warn().Err(err).Str("videoID", videoID).Msg("vide pipeline failed to write")
-			}
-		}
-
-		video.AddListener(&listener)
-		manager.unsubscribe = append(manager.unsubscribe, func(){
-			video.RemoveListener(&listener)
-		})
-
-		manager.videoTracks[videoID] = track
-	}
-
 	manager.logger.Info().
 		Str("ice_lite", fmt.Sprintf("%t", manager.config.ICELite)).
 		Str("ice_trickle", fmt.Sprintf("%t", manager.config.ICETrickle)).
@@ -159,12 +128,67 @@ func (manager *WebRTCManagerCtx) CreatePeer(session types.Session) (*webrtc.Sess
 		})
 	}
 
+	// create video track
+	videoStream, ok := manager.capture.Video(manager.defaultVideoID)
+	if !ok {
+		manager.logger.Warn().Str("videoID", manager.defaultVideoID).Msg("default video stream not found")
+		return nil, err
+	}
+
+	videoTrack, err := webrtc.NewTrackLocalStaticSample(videoStream.Codec().Capability, "video", "stream")
+	if err != nil {
+		manager.logger.Warn().Err(err).Msg("unable to create video track")
+		return nil, err
+	}
+
+	listener := func(sample types.Sample) {
+		if err := videoTrack.WriteSample(media.Sample(sample)); err != nil && err != io.ErrClosedPipe {
+			manager.logger.Warn().Err(err).Msg("video pipeline failed to write")
+		}
+	}
+
+	// should be stream started
+	if videoStream.ListenersCount() == 0 {
+		if err := videoStream.Start(); err != nil {
+			manager.logger.Warn().Err(err).Msg("unable to start video pipeline")
+			return nil, err
+		}
+	}
+
+	videoStream.AddListener(&listener)
+
+	changeVideo := func(videoID string) error {
+		newVideoStream, ok := manager.capture.Video(videoID)
+		if !ok {
+			return fmt.Errorf("video stream not found")
+		}
+
+		// should be new stream started
+		if newVideoStream.ListenersCount() == 0 {
+			if err := newVideoStream.Start(); err != nil {
+				return err
+			}
+		}
+
+		// switch listeners
+		videoStream.RemoveListener(&listener)
+		newVideoStream.AddListener(&listener)
+
+		// should be old stream stopped
+		if videoStream.ListenersCount() == 0 {
+			videoStream.Stop()
+		}
+	
+		videoStream = newVideoStream
+		return nil
+	}
+
 	_, err = connection.AddTrack(manager.audioTrack)
 	if err != nil {
 		return nil, err
 	}
 
-	videoSender, err := connection.AddTrack(manager.videoTracks[manager.defaultVideoID])
+	_, err = connection.AddTrack(videoTrack)
 	if err != nil {
 		return nil, err
 	}
@@ -208,6 +232,12 @@ func (manager *WebRTCManagerCtx) CreatePeer(session types.Session) (*webrtc.Sess
 			connection.Close()
 		case webrtc.PeerConnectionStateClosed:
 			session.SetWebRTCConnected(false)
+			videoStream.RemoveListener(&listener)
+
+			// should be stream stopped
+			if videoStream.ListenersCount() == 0 {
+				videoStream.Stop()
+			}
 		}
 	})
 
@@ -229,8 +259,7 @@ func (manager *WebRTCManagerCtx) CreatePeer(session types.Session) (*webrtc.Sess
 		settings:       settings,
 		connection:     connection,
 		configuration:  configuration,
-		videoTracks:    manager.videoTracks,
+		changeVideo:    changeVideo,
-		videoSender:    videoSender,
 	})
 
 	return connection.LocalDescription(), nil

internal/webrtc/peer.go

@@ -1,10 +1,6 @@
 package webrtc
 
-import (
+import "github.com/pion/webrtc/v3"
-	"fmt"
-
-	"github.com/pion/webrtc/v3"
-)
 
 type WebRTCPeerCtx struct {
 	api            *webrtc.API
@@ -12,8 +8,7 @@ type WebRTCPeerCtx struct {
 	settings       *webrtc.SettingEngine
 	connection     *webrtc.PeerConnection
 	configuration  *webrtc.Configuration
-	videoTracks    map[string]*webrtc.TrackLocalStaticSample
+	changeVideo    func(videoID string) error
-	videoSender    *webrtc.RTPSender
 }
 
 func (webrtc_peer *WebRTCPeerCtx) SignalAnswer(sdp string) error {
@@ -28,12 +23,7 @@ func (webrtc_peer *WebRTCPeerCtx) SignalCandidate(candidate webrtc.ICECandidateI
 }
 
 func (webrtc_peer *WebRTCPeerCtx) SetVideoID(videoID string) error {
-	track, ok := webrtc_peer.videoTracks[videoID]
+	return webrtc_peer.changeVideo(videoID)
-	if !ok {
-		return fmt.Errorf("videoID not found in available tracks")
-	}
-
-	return webrtc_peer.videoSender.ReplaceTrack(track)
 }
 
 func (webrtc_peer *WebRTCPeerCtx) Destroy() error {

internal/websocket/handler/session.go

@@ -29,9 +29,11 @@ func (h *MessageHandlerCtx) SessionDeleted(session types.Session) error {
 }
 
 func (h *MessageHandlerCtx) SessionConnected(session types.Session) error {
-	// start streaming, when first member connects
+	// start audio, when first member connects
-	if !h.capture.Streaming() {
+	if !h.capture.Audio().Started() {
-		h.capture.StartStream()
+		if err := h.capture.Audio().Start(); err != nil {
+			return err
+		}
 	}
 
 	if err := h.systemInit(session); err != nil {
@@ -48,9 +50,9 @@ func (h *MessageHandlerCtx) SessionConnected(session types.Session) error {
 }
 
 func (h *MessageHandlerCtx) SessionDisconnected(session types.Session) error {
-	// Stop streaming, if last member disonnects
+	// stop audio, if last member disonnects
-	if h.capture.Streaming() && !h.sessions.HasConnectedMembers() {
+	if h.capture.Audio().Started() && !h.sessions.HasConnectedMembers() {
-		h.capture.StopStream()
+		h.capture.Audio().Stop()
 	}
 
 	// clear host if exists