add Trickle ICE support.

internal/session/session.go

@@ -2,6 +2,7 @@ package session
 
 import (
 	"github.com/rs/zerolog"
+	"github.com/pion/webrtc/v3"
 
 	"demodesk/neko/internal/types"
 	"demodesk/neko/internal/types/event"
@@ -195,3 +196,11 @@ func (session *SessionCtx) SignalAnswer(sdp string) error {
 
 	return session.webrtc_peer.SignalAnswer(sdp)
 }
+
+func (session *SessionCtx) SignalCandidate(candidate webrtc.ICECandidateInit) error {
+	if session.webrtc_peer == nil {
+		return nil
+	}
+
+	return session.webrtc_peer.SignalCandidate(candidate)
+}

internal/types/event/events.go

@@ -10,6 +10,7 @@ const (
 	SIGNAL_REQUEST   = "signal/request"
 	SIGNAL_ANSWER    = "signal/answer"
 	SIGNAL_PROVIDE   = "signal/provide"
+	SIGNAL_CANDIDATE = "signal/candidate"
 )
 
 const (

internal/types/message/messages.go

@@ -1,6 +1,8 @@
 package message
 
 import (
+	"github.com/pion/webrtc/v3"
+
 	"demodesk/neko/internal/types"
 )
 
@@ -45,6 +47,11 @@ type SignalProvide struct {
 	ICE   []string `json:"ice"`
 }
 
+type SignalCandidate struct {
+	Event string `json:"event,omitempty"`
+	*webrtc.ICECandidateInit
+}
+
 type SignalAnswer struct {
 	Event string `json:"event,omitempty"`
 	SDP   string `json:"sdp"`

internal/types/session.go

@@ -1,6 +1,10 @@
 package types
 
-import "net/http"
+import (
+	"net/http"
+
+	"github.com/pion/webrtc/v3"
+)
 
 type MemberProfile struct {
 	Secret             string `json:"secret,omitempty"`
@@ -58,6 +62,7 @@ type Session interface {
 	SetWebRTCPeer(webrtc_peer WebRTCPeer)
 	SetWebRTCConnected(connected bool)
 	SignalAnswer(sdp string) error
+	SignalCandidate(candidate webrtc.ICECandidateInit) error
 }
 
 type SessionManager interface {

internal/types/webrtc.go

@@ -4,6 +4,8 @@ import "github.com/pion/webrtc/v3"
 
 type WebRTCPeer interface {
 	SignalAnswer(sdp string) error
+	SignalCandidate(candidate webrtc.ICECandidateInit) error
+
 	Destroy() error
 }
 

internal/webrtc/manager.go

@@ -12,6 +12,8 @@ import (
 
 	"demodesk/neko/internal/types"
 	"demodesk/neko/internal/types/codec"
+	"demodesk/neko/internal/types/event"
+	"demodesk/neko/internal/types/message"
 	"demodesk/neko/internal/config"
 )
 
@@ -86,45 +88,57 @@ func (manager *WebRTCManagerCtx) ICEServers() []string {
 }
 
 func (manager *WebRTCManagerCtx) CreatePeer(session types.Session) (*webrtc.SessionDescription, error) {
-	// Create MediaEngine
+	logger := manager.logger.With().Str("id", session.ID()).Logger()
+
 	engine, err := manager.mediaEngine()
 	if err != nil {
 		return nil, err
 	}
 
 	// Custom settings & configuration
-	settings := manager.apiSettings(session)
+	settings := manager.apiSettings(logger)
 	configuration := manager.apiConfiguration()
 
 	// Create NewAPI with MediaEngine and SettingEngine
 	api := webrtc.NewAPI(webrtc.WithMediaEngine(engine), webrtc.WithSettingEngine(*settings))
 
-	// Create NewPeerConnection
 	connection, err := api.NewPeerConnection(*configuration)
 	if err != nil {
 		return nil, err
 	}
 
-	// Register video, audio & data tracks
+	// Asynchronously send local ICE Candidates
+	connection.OnICECandidate(func(candidate *webrtc.ICECandidate) {
+		if candidate == nil {
+			logger.Debug().Msg("all local ice candidates sent")
+			return
+		}
+
+		ICECandidateInit := candidate.ToJSON()
+		err := session.Send(
+			message.SignalCandidate{
+				Event:            event.SIGNAL_CANDIDATE,
+				ICECandidateInit: &ICECandidateInit,
+			})
+
+		if err != nil {
+			logger.Warn().Err(err).Msg("sending ice candidate failed")
+		}
+	})
+
 	if err := manager.registerTracks(connection); err != nil {
 		return nil, err
 	}
 
-	// Create Offer
 	offer, err := connection.CreateOffer(nil)
 	if err != nil {
 		return nil, err
 	}
 
-	// TODO: Refactor, send request to client.
-	gatherComplete := webrtc.GatheringCompletePromise(connection)
-
 	if err := connection.SetLocalDescription(offer); err != nil {
 		return nil, err
 	}
 
-	<-gatherComplete
-
 	connection.OnConnectionStateChange(func(state webrtc.PeerConnectionState) {
 		switch state {
 		case webrtc.PeerConnectionStateConnected:
@@ -145,7 +159,7 @@ func (manager *WebRTCManagerCtx) CreatePeer(session types.Session) (*webrtc.Sess
 			}
 
 			if err = manager.handle(message); err != nil {
-				manager.logger.Warn().Err(err).Msg("data handle failed")
+				logger.Warn().Err(err).Msg("data handle failed")
 			}
 		})
 	})
@@ -176,10 +190,10 @@ func (manager *WebRTCManagerCtx) mediaEngine() (*webrtc.MediaEngine, error) {
 	return engine, nil
 }
 
-func (manager *WebRTCManagerCtx) apiSettings(session types.Session) *webrtc.SettingEngine {
+func (manager *WebRTCManagerCtx) apiSettings(logger zerolog.Logger) *webrtc.SettingEngine {
 	settings := &webrtc.SettingEngine{
 		LoggerFactory: loggerFactory{
-			logger: manager.logger.With().Str("id", session.ID()).Logger(),
+			logger: logger,
 		},
 	}
 

internal/webrtc/peer.go

@@ -17,6 +17,10 @@ func (webrtc_peer *WebRTCPeerCtx) SignalAnswer(sdp string) error {
 	})
 }
 
+func (webrtc_peer *WebRTCPeerCtx) SignalCandidate(candidate webrtc.ICECandidateInit) error {
+	return webrtc_peer.connection.AddICECandidate(candidate)
+}
+
 func (webrtc_peer *WebRTCPeerCtx) Destroy() error {
 	if webrtc_peer.connection == nil || webrtc_peer.connection.ConnectionState() != webrtc.PeerConnectionStateConnected {
 		return nil

internal/websocket/handler/handler.go

@@ -54,6 +54,11 @@ func (h *MessageHandlerCtx) Message(session types.Session, raw []byte) bool {
 		err = utils.Unmarshal(payload, raw, func() error {
 			return h.signalAnswer(session, payload)
 		})
+	case event.SIGNAL_CANDIDATE:
+		payload := &message.SignalCandidate{}
+		err = utils.Unmarshal(payload, raw, func() error {
+			return h.signalCandidate(session, payload)
+		})
 
 	// Control Events
 	case event.CONTROL_RELEASE:

internal/websocket/handler/signal.go

@@ -28,3 +28,7 @@ func (h *MessageHandlerCtx) signalRequest(session types.Session) error {
 func (h *MessageHandlerCtx) signalAnswer(session types.Session, payload *message.SignalAnswer) error {
 	return session.SignalAnswer(payload.SDP)
 }
+
+func (h *MessageHandlerCtx) signalCandidate(session types.Session, payload *message.SignalCandidate) error {
+	return session.SignalCandidate(*payload.ICECandidateInit)
+}