handles RTC join

pkg/rtc/peer.go

@@ -28,7 +28,7 @@ type WebRTCPeer struct {
 	// OnOffer - offer is ready for remote peer
 	OnOffer func(webrtc.SessionDescription)
 	// OnIceCandidate - ice candidate discovered for local peer
-	OnICECandidate func(c *webrtc.ICECandidate)
+	OnICECandidate func(c *webrtc.ICECandidateInit)
 	OnClose        func(*WebRTCPeer)
 }
 
@@ -76,7 +76,8 @@ func NewWebRTCPeer(id string, me *MediaEngine, conf WebRTCConfig) (*WebRTCPeer,
 			return
 		}
 		if peer.OnICECandidate != nil {
-			peer.OnICECandidate(c)
+			ci := c.ToJSON()
+			peer.OnICECandidate(&ci)
 		}
 	})
 

pkg/rtc/room.go

@@ -52,6 +52,8 @@ func (r *Room) ToRoomInfo(node *livekit.Node) *livekit.RoomInfo {
 }
 
 func (r *Room) Join(peerId string, token string, sdp string) (peer *WebRTCPeer, err error) {
+	// TODO: check token and reject
+
 	r.lock.Lock()
 	defer r.lock.Unlock()
 

pkg/service/rtc.go

@@ -1,6 +1,14 @@
 package service
 
 import (
+	"encoding/json"
+	"io"
+
+	"github.com/pion/webrtc/v3"
+	"google.golang.org/grpc/codes"
+	"google.golang.org/grpc/status"
+
+	"github.com/livekit/livekit-server/pkg/logger"
 	"github.com/livekit/livekit-server/pkg/rtc"
 	"github.com/livekit/livekit-server/proto/livekit"
 )
@@ -10,12 +18,115 @@ type RTCService struct {
 	manager *rtc.RoomManager
 }
 
-func (s *RTCService) Signal(stream livekit.RTCService_SignalServer) error {
-	return nil
-}
-
 func NewRTCService(manager *rtc.RoomManager) *RTCService {
 	return &RTCService{
 		manager: manager,
 	}
 }
+
+// each client establishes a persistent signaling connection to the server
+// when the connection is terminated, WebRTC session shall end
+// similarly, when WebRTC connection is disconnected, we'll terminate signaling
+func (s *RTCService) Signal(stream livekit.RTCService_SignalServer) error {
+	var peer *rtc.WebRTCPeer
+	for {
+		req, err := stream.Recv()
+		if err != nil {
+			if peer != nil {
+				peer.Close()
+
+				if err == io.EOF {
+					return nil
+				}
+
+				errStatus, _ := status.FromError(err)
+				if errStatus.Code() == codes.Canceled {
+					return nil
+				}
+
+				logger.GetLogger().Errorf("signaling error", errStatus.Message(), errStatus.Code())
+				return err
+			}
+		}
+
+		switch msg := req.Message.(type) {
+		case *livekit.SignalRequest_Join:
+			peer, err = s.handleJoin(msg.Join, stream)
+		case *livekit.SignalRequest_Negotiate:
+			if peer == nil {
+				return status.Errorf(codes.FailedPrecondition, "peer has not joined yet")
+			}
+
+		}
+	}
+	return nil
+}
+
+func (s *RTCService) handleJoin(join *livekit.JoinRequest, stream livekit.RTCService_SignalServer) (*rtc.WebRTCPeer, error) {
+	// join a room
+	room := s.manager.GetRoom(join.RoomId)
+	if room == nil {
+		return nil, status.Errorf(codes.NotFound, "room %s doesn't exist", join.RoomId)
+	}
+	peer, err := room.Join(join.PeerId, join.Token, join.Offer.Sdp)
+	if err != nil {
+		return nil, status.Errorf(codes.Internal, "could not join room: %v", err)
+	}
+
+	offer := webrtc.SessionDescription{
+		Type: webrtc.SDPTypeOffer,
+		SDP:  string(join.Offer.Sdp),
+	}
+	answer, err := peer.Answer(offer)
+	if err != nil {
+		return nil, status.Errorf(codes.Internal, "could not answer offer: %v", err)
+	}
+
+	// TODO: it might be better to return error instead of nil
+	peer.OnICECandidate = func(c *webrtc.ICECandidateInit) {
+		bytes, err := json.Marshal(c)
+		if err != nil {
+			logger.GetLogger().Errorf("could not marshal ice candidate: %v", err)
+			return
+		}
+
+		err = stream.Send(&livekit.SignalResponse{
+			Message: &livekit.SignalResponse_Trickle{
+				Trickle: &livekit.Trickle{
+					CandidateInit: string(bytes),
+				},
+			},
+		})
+		if err != nil {
+			logger.GetLogger().Errorw("could not send trickle", "err", err)
+		}
+	}
+
+	// send peer new offer
+	peer.OnOffer = func(o webrtc.SessionDescription) {
+		err := stream.Send(&livekit.SignalResponse{
+			Message: &livekit.SignalResponse_Negotiate{
+				Negotiate: ToProtoSessionDescription(&o),
+			},
+		})
+		if err != nil {
+			logger.GetLogger().Errorw("could not send offer to peer",
+				"err", err)
+		}
+	}
+
+	// finally send answer
+	err = stream.Send(&livekit.SignalResponse{
+		Message: &livekit.SignalResponse_Join{
+			Join: &livekit.JoinResponse{
+				Answer: ToProtoSessionDescription(&answer),
+			},
+		},
+	})
+
+	if err != nil {
+		return nil, status.Errorf(codes.Internal, "could not join: %v", err)
+	}
+
+	return peer, nil
+}

pkg/service/utils.go

@@ -0,0 +1,14 @@
+package service
+
+import (
+	"github.com/pion/webrtc/v3"
+
+	"github.com/livekit/livekit-server/proto/livekit"
+)
+
+func ToProtoSessionDescription(sd *webrtc.SessionDescription) *livekit.SessionDescription {
+	return &livekit.SessionDescription{
+		Type: sd.Type.String(),
+		Sdp:  sd.SDP,
+	}
+}

proto/livekit/rtc.pb.go

@@ -117,7 +117,7 @@ func (*SignalRequest) XXX_OneofWrappers() []interface{} {
 
 type SignalResponse struct {
 	// Types that are valid to be assigned to Message:
-	//	*SignalResponse_Jin
+	//	*SignalResponse_Join
 	//	*SignalResponse_Negotiate
 	//	*SignalResponse_Trickle
 	Message              isSignalResponse_Message `protobuf_oneof:"message"`
@@ -155,8 +155,8 @@ type isSignalResponse_Message interface {
 	isSignalResponse_Message()
 }
 
-type SignalResponse_Jin struct {
-	Jin *JoinResponse `protobuf:"bytes,1,opt,name=jin,proto3,oneof"`
+type SignalResponse_Join struct {
+	Join *JoinResponse `protobuf:"bytes,1,opt,name=join,proto3,oneof"`
 }
 
 type SignalResponse_Negotiate struct {
@@ -167,7 +167,7 @@ type SignalResponse_Trickle struct {
 	Trickle *Trickle `protobuf:"bytes,3,opt,name=trickle,proto3,oneof"`
 }
 
-func (*SignalResponse_Jin) isSignalResponse_Message() {}
+func (*SignalResponse_Join) isSignalResponse_Message() {}
 
 func (*SignalResponse_Negotiate) isSignalResponse_Message() {}
 
@@ -180,9 +180,9 @@ func (m *SignalResponse) GetMessage() isSignalResponse_Message {
 	return nil
 }
 
-func (m *SignalResponse) GetJin() *JoinResponse {
-	if x, ok := m.GetMessage().(*SignalResponse_Jin); ok {
-		return x.Jin
+func (m *SignalResponse) GetJoin() *JoinResponse {
+	if x, ok := m.GetMessage().(*SignalResponse_Join); ok {
+		return x.Join
 	}
 	return nil
 }
@@ -204,7 +204,7 @@ func (m *SignalResponse) GetTrickle() *Trickle {
 // XXX_OneofWrappers is for the internal use of the proto package.
 func (*SignalResponse) XXX_OneofWrappers() []interface{} {
 	return []interface{}{
-		(*SignalResponse_Jin)(nil),
+		(*SignalResponse_Join)(nil),
 		(*SignalResponse_Negotiate)(nil),
 		(*SignalResponse_Trickle)(nil),
 	}
@@ -411,31 +411,31 @@ func init() {
 func init() { proto.RegisterFile("rtc.proto", fileDescriptor_85bd91e80f756774) }
 
 var fileDescriptor_85bd91e80f756774 = []byte{
-	// 406 bytes of a gzipped FileDescriptorProto
-	0x1f, 0x8b, 0x08, 0x00, 0x00, 0x00, 0x00, 0x00, 0x02, 0xff, 0xc4, 0x93, 0xcf, 0x6e, 0xd3, 0x40,
-	0x10, 0x87, 0x63, 0x92, 0xda, 0xf2, 0x94, 0x56, 0xd5, 0xa8, 0x50, 0x0b, 0x2e, 0xc8, 0x12, 0x52,
-	0x41, 0xe0, 0xf4, 0xcf, 0x0d, 0xc4, 0xa5, 0xe5, 0xe0, 0xc0, 0x6d, 0xd3, 0x13, 0x97, 0xca, 0xb5,
-	0xa7, 0x66, 0x9a, 0x64, 0xd7, 0xec, 0x6e, 0x83, 0x78, 0x03, 0x5e, 0x87, 0x37, 0x44, 0x5e, 0xaf,
-	0xdd, 0x88, 0x48, 0x70, 0xe4, 0xe4, 0x9d, 0xd1, 0xf7, 0x5b, 0x7d, 0x33, 0xb6, 0x21, 0xd6, 0xb6,
-	0xcc, 0x1a, 0xad, 0xac, 0xc2, 0x68, 0xc9, 0x6b, 0x5a, 0xb0, 0x4d, 0x7f, 0x05, 0xb0, 0x37, 0xe7,
-	0x5a, 0x16, 0x4b, 0x41, 0xdf, 0xee, 0xc9, 0x58, 0x7c, 0x0d, 0x93, 0x3b, 0xc5, 0x32, 0x09, 0x5e,
-	0x04, 0xc7, 0xbb, 0x67, 0x87, 0x99, 0x27, 0xb3, 0x4f, 0x8a, 0xa5, 0x67, 0xf2, 0x91, 0x70, 0x0c,
-	0xbe, 0x87, 0x58, 0x52, 0xad, 0x2c, 0x17, 0x96, 0x92, 0x47, 0x2e, 0xf0, 0x7c, 0x08, 0xcc, 0xc9,
-	0x18, 0x56, 0xf2, 0x23, 0x99, 0x52, 0x73, 0x63, 0x59, 0xc9, 0x7c, 0x24, 0x1e, 0x78, 0x7c, 0x03,
-	0x91, 0xd5, 0x5c, 0x2e, 0x96, 0x94, 0x8c, 0x5d, 0xf4, 0x60, 0x88, 0x5e, 0x75, 0xfd, 0x7c, 0x24,
-	0x7a, 0xe4, 0x22, 0x86, 0x68, 0x45, 0xc6, 0x14, 0x35, 0xb5, 0xce, 0xfb, 0xbd, 0xb3, 0x69, 0x94,
-	0x34, 0x84, 0xaf, 0x60, 0x7c, 0x37, 0x38, 0x3f, 0xf9, 0xc3, 0xb9, 0x63, 0xf2, 0x91, 0x68, 0x99,
-	0xff, 0xe4, 0xfc, 0x33, 0x80, 0xdd, 0x8d, 0x0d, 0xe2, 0x11, 0x44, 0x5a, 0xa9, 0xd5, 0x35, 0x57,
-	0x4e, 0x3a, 0x16, 0x61, 0x5b, 0xce, 0x2a, 0x3c, 0x84, 0x1d, 0xab, 0x16, 0x24, 0x9d, 0x5a, 0x2c,
-	0xba, 0xa2, 0xc5, 0x1b, 0x22, 0xdd, 0xe2, 0xe3, 0x0e, 0x6f, 0xcb, 0x59, 0x85, 0xa7, 0xb0, 0xa3,
-	0x6e, 0x6f, 0x49, 0x27, 0x93, 0x7f, 0x4e, 0x22, 0x3a, 0x32, 0xbd, 0x84, 0xc7, 0x9b, 0x7b, 0xc1,
-	0x73, 0x08, 0x0b, 0x69, 0xbe, 0x93, 0xf6, 0xeb, 0xfb, 0xeb, 0x1d, 0x1e, 0x4d, 0x4f, 0x20, 0xf2,
-	0x03, 0xe3, 0x4b, 0xd8, 0x2f, 0x0b, 0x59, 0x71, 0x55, 0x58, 0xba, 0x66, 0xc9, 0xd6, 0x4f, 0xb4,
-	0x37, 0x74, 0x67, 0x92, 0x6d, 0xfa, 0x0e, 0x70, 0xfb, 0x3e, 0x44, 0x98, 0xd8, 0x1f, 0x0d, 0xf9,
-	0x88, 0x3b, 0xe3, 0x01, 0x8c, 0x4d, 0xd5, 0xf8, 0x05, 0xb4, 0xc7, 0xb3, 0xcf, 0x00, 0xe2, 0xea,
-	0x72, 0x4e, 0x7a, 0xcd, 0x25, 0xe1, 0x07, 0x08, 0xbb, 0xd7, 0x8f, 0x4f, 0x1f, 0x54, 0x37, 0xbf,
-	0xe1, 0x67, 0x47, 0x5b, 0xfd, 0x6e, 0xd6, 0xe3, 0xe0, 0x24, 0xb8, 0x38, 0xfd, 0x32, 0xad, 0xd9,
-	0x7e, 0xbd, 0xbf, 0xc9, 0x4a, 0xb5, 0x9a, 0x7a, 0xb0, 0x7f, 0xbe, 0x35, 0xa4, 0xd7, 0xa4, 0xa7,
-	0xee, 0x37, 0xe9, 0x9b, 0x37, 0xa1, 0x2b, 0xcf, 0x7f, 0x07, 0x00, 0x00, 0xff, 0xff, 0xa9, 0x3d,
-	0xb9, 0xb1, 0x42, 0x03, 0x00, 0x00,
+	// 403 bytes of a gzipped FileDescriptorProto
+	0x1f, 0x8b, 0x08, 0x00, 0x00, 0x00, 0x00, 0x00, 0x02, 0xff, 0xc4, 0x93, 0x4f, 0x6f, 0xd3, 0x40,
+	0x10, 0xc5, 0x63, 0x92, 0xda, 0xf2, 0x94, 0x56, 0xd5, 0xa8, 0x50, 0x0b, 0x2e, 0xc8, 0x12, 0x52,
+	0xc5, 0x1f, 0xa7, 0x7f, 0x6e, 0x20, 0x2e, 0x2d, 0x87, 0x04, 0x6e, 0x9b, 0x9e, 0xb8, 0x54, 0xae,
+	0x3d, 0x31, 0x43, 0x92, 0x5d, 0xb3, 0xbb, 0x09, 0xe2, 0x1b, 0xf0, 0x75, 0x10, 0x5f, 0x10, 0x79,
+	0xbd, 0x4e, 0x02, 0x91, 0xe0, 0xd8, 0x93, 0x77, 0x46, 0xbf, 0xb7, 0x7a, 0xef, 0x69, 0x0d, 0xb1,
+	0xb6, 0x45, 0x56, 0x6b, 0x65, 0x15, 0x46, 0x73, 0x5e, 0xd1, 0x8c, 0x6d, 0xfa, 0x33, 0x80, 0x83,
+	0x09, 0x57, 0x32, 0x9f, 0x0b, 0xfa, 0xba, 0x24, 0x63, 0xf1, 0x05, 0x0c, 0xbe, 0x28, 0x96, 0x49,
+	0xf0, 0x2c, 0x38, 0xdd, 0xbf, 0x38, 0xce, 0x3c, 0x99, 0x7d, 0x50, 0x2c, 0x3d, 0x33, 0xea, 0x09,
+	0xc7, 0xe0, 0x5b, 0x88, 0x25, 0x55, 0xca, 0x72, 0x6e, 0x29, 0x79, 0xe0, 0x04, 0x4f, 0xd7, 0x82,
+	0x09, 0x19, 0xc3, 0x4a, 0xbe, 0x27, 0x53, 0x68, 0xae, 0x2d, 0x2b, 0x39, 0xea, 0x89, 0x0d, 0x8f,
+	0xaf, 0x20, 0xb2, 0x9a, 0x8b, 0xd9, 0x9c, 0x92, 0xbe, 0x93, 0x1e, 0xad, 0xa5, 0x37, 0xed, 0x7e,
+	0xd4, 0x13, 0x1d, 0x72, 0x15, 0x43, 0xb4, 0x20, 0x63, 0xf2, 0x8a, 0xd2, 0x5f, 0x01, 0x1c, 0x76,
+	0x9e, 0x4d, 0xad, 0xa4, 0x21, 0x7c, 0xf9, 0x87, 0xe9, 0x47, 0x7f, 0x99, 0x6e, 0xa1, 0x7b, 0x76,
+	0xfd, 0x23, 0x80, 0xfd, 0xad, 0x0e, 0xf1, 0x04, 0x22, 0xad, 0xd4, 0xe2, 0x96, 0x4b, 0xe7, 0x3a,
+	0x16, 0x61, 0x33, 0x8e, 0x4b, 0x3c, 0x86, 0x3d, 0xab, 0x66, 0x24, 0x9d, 0xb5, 0x58, 0xb4, 0x43,
+	0x83, 0xd7, 0x44, 0xba, 0xc1, 0xfb, 0x2d, 0xde, 0x8c, 0xe3, 0x12, 0xcf, 0x61, 0x4f, 0x4d, 0xa7,
+	0xa4, 0x93, 0xc1, 0x7f, 0x93, 0x88, 0x96, 0x4c, 0xaf, 0xe1, 0xe1, 0x76, 0x31, 0x78, 0x09, 0x61,
+	0x2e, 0xcd, 0x37, 0xd2, 0xbe, 0xbf, 0x7f, 0xde, 0xe1, 0xd1, 0xf4, 0x0c, 0x22, 0x1f, 0x18, 0x9f,
+	0xc3, 0x61, 0x91, 0xcb, 0x92, 0xcb, 0xdc, 0xd2, 0x2d, 0x4b, 0xb6, 0x3e, 0xd1, 0xc1, 0x7a, 0x3b,
+	0x96, 0x6c, 0xd3, 0x37, 0x80, 0xbb, 0xf7, 0x21, 0xc2, 0xc0, 0x7e, 0xaf, 0xc9, 0x4b, 0xdc, 0x19,
+	0x8f, 0xa0, 0x6f, 0xca, 0xda, 0x17, 0xd0, 0x1c, 0x2f, 0x3e, 0x02, 0x88, 0x9b, 0xeb, 0x09, 0xe9,
+	0x15, 0x17, 0x84, 0xef, 0x20, 0x6c, 0x1f, 0x00, 0x3e, 0xde, 0x58, 0xdd, 0x7e, 0xc5, 0x4f, 0x4e,
+	0x76, 0xf6, 0x6d, 0xd6, 0xd3, 0xe0, 0x2c, 0xb8, 0x3a, 0xff, 0x34, 0xac, 0xd8, 0x7e, 0x5e, 0xde,
+	0x65, 0x85, 0x5a, 0x0c, 0x3d, 0xd8, 0x7d, 0x5f, 0x1b, 0xd2, 0x2b, 0xd2, 0x43, 0xf7, 0xa3, 0x74,
+	0xcb, 0xbb, 0xd0, 0x8d, 0x97, 0xbf, 0x03, 0x00, 0x00, 0xff, 0xff, 0x00, 0xe8, 0xef, 0x85, 0x44,
+	0x03, 0x00, 0x00,
 }

proto/rtc.proto

@@ -18,7 +18,7 @@ message SignalRequest {
 
 message SignalResponse {
   oneof message {
-    JoinResponse jin = 1;
+    JoinResponse join = 1;
     SessionDescription negotiate = 2;
     Trickle trickle = 3;
   }