audio start / stop in WebRTC.

internal/webrtc/manager.go

@@ -5,6 +5,7 @@ import (
 	"io"
 	"reflect"
 	"strings"
+	"sync"
 
 	"github.com/pion/webrtc/v3"
 	"github.com/pion/webrtc/v3/pkg/media"
@@ -19,10 +20,11 @@ import (
 
 func New(desktop types.DesktopManager, capture types.CaptureManager, config *config.WebRTC) *WebRTCManagerCtx {
 	return &WebRTCManagerCtx{
-		logger:  log.With().Str("module", "webrtc").Logger(),
-		desktop: desktop,
-		capture: capture,
-		config:  config,
+		logger:       log.With().Str("module", "webrtc").Logger(),
+		desktop:      desktop,
+		capture:      capture,
+		config:       config,
+		participants: 0,
 		// TODO: Refactor.
 		curImgListeners: map[uintptr]*func(cur *types.CursorImage){},
 		curPosListeners: map[uintptr]*func(x, y int){},
@@ -30,12 +32,14 @@ func New(desktop types.DesktopManager, capture types.CaptureManager, config *con
 }
 
 type WebRTCManagerCtx struct {
-	logger     zerolog.Logger
-	audioTrack *webrtc.TrackLocalStaticSample
-	audioStop  func()
-	desktop    types.DesktopManager
-	capture    types.CaptureManager
-	config     *config.WebRTC
+	mu           sync.Mutex
+	logger       zerolog.Logger
+	audioTrack   *webrtc.TrackLocalStaticSample
+	audioStop    func()
+	desktop      types.DesktopManager
+	capture      types.CaptureManager
+	config       *config.WebRTC
+	participants uint32
 	// TODO: Refactor.
 	curImgListeners map[uintptr]*func(cur *types.CursorImage)
 	curPosListeners map[uintptr]*func(x, y int)
@@ -51,15 +55,15 @@ func (manager *WebRTCManagerCtx) Start() {
 		manager.logger.Panic().Err(err).Msg("unable to create audio track")
 	}
 
-	listener := func(sample types.Sample) {
+	audioListener := func(sample types.Sample) {
 		if err := manager.audioTrack.WriteSample(media.Sample(sample)); err != nil && err != io.ErrClosedPipe {
 			manager.logger.Warn().Err(err).Msg("audio pipeline failed to write")
 		}
 	}
 
-	audio.AddListener(&listener)
+	audio.AddListener(&audioListener)
 	manager.audioStop = func() {
-		audio.RemoveListener(&listener)
+		audio.RemoveListener(&audioListener)
 	}
 
 	manager.logger.Info().
@@ -156,12 +160,14 @@ func (manager *WebRTCManagerCtx) CreatePeer(session types.Session, videoID strin
 		return nil, err
 	}
 
-	listener := func(sample types.Sample) {
+	videoListener := 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")
 		}
 	}
 
+	manager.mu.Lock()
+
 	// should be stream started
 	if videoStream.ListenersCount() == 0 {
 		if err := videoStream.Start(); err != nil {
@@ -170,7 +176,17 @@ func (manager *WebRTCManagerCtx) CreatePeer(session types.Session, videoID strin
 		}
 	}
 
-	videoStream.AddListener(&listener)
+	videoStream.AddListener(&videoListener)
+
+	// start audio, when first participant connects
+	if !manager.capture.Audio().Started() {
+		if err := manager.capture.Audio().Start(); err != nil {
+			manager.logger.Panic().Err(err).Msg("unable to start audio stream")
+		}
+	}
+
+	manager.participants = manager.participants + 1
+	manager.mu.Unlock()
 
 	changeVideo := func(videoID string) error {
 		newVideoStream, ok := manager.capture.Video(videoID)
@@ -185,9 +201,9 @@ func (manager *WebRTCManagerCtx) CreatePeer(session types.Session, videoID strin
 			}
 		}
 
-		// switch listeners
-		videoStream.RemoveListener(&listener)
-		newVideoStream.AddListener(&listener)
+		// switch videoListeners
+		videoStream.RemoveListener(&videoListener)
+		newVideoStream.AddListener(&videoListener)
 
 		// should be old stream stopped
 		if videoStream.ListenersCount() == 0 {
@@ -269,17 +285,33 @@ func (manager *WebRTCManagerCtx) CreatePeer(session types.Session, videoID strin
 		case webrtc.PeerConnectionStateFailed:
 			connection.Close()
 		case webrtc.PeerConnectionStateClosed:
+			manager.mu.Lock()
+
 			session.SetWebRTCConnected(peer, false)
-			videoStream.RemoveListener(&listener)
+			videoStream.RemoveListener(&videoListener)
 
 			// should be stream stopped
 			if videoStream.ListenersCount() == 0 {
 				videoStream.Stop()
 			}
 
+			// decrease participants
+			manager.participants = manager.participants - 1
+
+			// stop audio, if last participant disonnects
+			if manager.participants <= 0 {
+				manager.participants = 0
+
+				if manager.capture.Audio().Started() {
+					manager.capture.Audio().Stop()
+				}
+			}
+
 			// TODO: Refactor.
 			delete(manager.curImgListeners, cursorChangePtr)
 			delete(manager.curPosListeners, cursorPositionPtr)
+
+			manager.mu.Unlock()
 		}
 	})
 

internal/websocket/handler/session.go

@@ -29,13 +29,6 @@ func (h *MessageHandlerCtx) SessionDeleted(session types.Session) error {
 }
 
 func (h *MessageHandlerCtx) SessionConnected(session types.Session) error {
-	// start audio, when first member connects
-	if !h.capture.Audio().Started() {
-		if err := h.capture.Audio().Start(); err != nil {
-			return err
-		}
-	}
-
 	if err := h.systemInit(session); err != nil {
 		return err
 	}
@@ -50,11 +43,6 @@ func (h *MessageHandlerCtx) SessionConnected(session types.Session) error {
 }
 
 func (h *MessageHandlerCtx) SessionDisconnected(session types.Session) error {
-	// stop audio, if last member disonnects
-	if h.capture.Audio().Started() && !h.sessions.HasConnectedMembers() {
-		h.capture.Audio().Stop()
-	}
-
 	// clear host if exists
 	if session.IsHost() {
 		h.desktop.ResetKeys()