Started using detached datachannels for performance boost

conn.go

@@ -1,7 +1,6 @@
 package rtcnet
 
 import (
-	"fmt"
 	"net"
 	"time"
 	"sync"
@@ -9,11 +8,14 @@ import (
 	"errors"
 
 	"github.com/pion/webrtc/v3"
+	"github.com/pion/datachannel"
 )
 
 type Conn struct {
 	peerConn *webrtc.PeerConnection
 	dataChannel *webrtc.DataChannel
+	raw datachannel.ReadWriteCloser
+
 	readChan chan []byte
 	errorChan chan error
 
@@ -23,18 +25,10 @@ type Conn struct {
 func newConn(peer *webrtc.PeerConnection) *Conn {
 	return &Conn{
 		peerConn: peer,
-		readChan: make(chan []byte, 1024), //TODO! - Sizing
 		errorChan: make(chan error, 16), //TODO! - Sizing
 	}
 }
 
-// For pushing read data out of the datachannel and into the read buffer
-func (c *Conn) pushReadData(dat []byte) {
-	if c.closed.Load() { return } // Skip if we are already closed
-
-	c.readChan <- dat
-}
-
 // For pushing error data out of the webrtc connection into the error buffer
 func (c *Conn) pushErrorData(err error) {
 	if c.closed.Load() { return } // Skip if we are already closed
@@ -45,30 +39,16 @@ func (c *Conn) pushErrorData(err error) {
 
 func (c *Conn) Read(b []byte) (int, error) {
 	select {
-	case err, ok := <-c.errorChan:
-		if !ok {
-			return 0, net.ErrClosed
-		}
+	case err := <-c.errorChan:
 		return 0, err // There was some error
-
-		case dat, ok := <- c.readChan:
-		if !ok {
-			return 0, net.ErrClosed
-		}
-		if len(dat) > len(b) {
-			return 0, fmt.Errorf("message too big") // TODO - Instead of failing, should we just return partial?
-		}
-		copy(b, dat)
-		return len(dat), nil
+	default:
+		// Just exit
 	}
+	return c.raw.Read(b)
 }
 
 func (c *Conn) Write(b []byte) (int, error) {
-	err := c.dataChannel.Send(b)
-	if err != nil {
-		return 0, err
-	}
-	return len(b), nil
+	return c.raw.Write(b)
 }
 
 func (c *Conn) Close() error {
@@ -79,12 +59,12 @@ func (c *Conn) Close() error {
 
 		err1 := c.dataChannel.Close()
 		err2 := c.peerConn.Close()
+		err3 := c.raw.Close()
 
-		close(c.readChan)
 		close(c.errorChan)
 
-		if err1 != nil || err2 != nil {
-			closeErr = errors.Join(errors.New("failed to close: (datachannel, peerconn)"), err1, err2)
+		if err1 != nil || err2 != nil || err3 != nil {
+			closeErr = errors.Join(errors.New("failed to close: (datachannel, peerconn, raw)"), err1, err2, err3)
 			logErr("conn: closing error: ", closeErr)
 		}
 	})

conn_test.go

@@ -126,10 +126,15 @@ func TestConn(t *testing.T) {
 				compare(t, buf[i], dat[i])
 			}
 
+			fmt.Printf(".")
 			successCount++
 		}
 
 		fmt.Println("Success: ", successCount)
+		err = conn.Close()
+		if err != nil {
+			fmt.Errorf("%v", err)
+		}
 	}
 
 	fmt.Println("Done")

dial.go

@@ -31,7 +31,9 @@ func Dial(address string, tlsConfig *tls.Config) (*Conn, error) {
 
 	trace("Dial: Starting WebRTC negotiation")
 
-	peerConnection, err := webrtc.NewPeerConnection(config)
+	api := getSettingsEngineApi()
+
+	peerConnection, err := api.NewPeerConnection(config)
 	if err != nil {
 		logErr("Dial: NewPeerConnection", err)
 		return nil, err
@@ -170,19 +172,26 @@ func Dial(address string, tlsConfig *tls.Config) (*Conn, error) {
 	dataChannel.OnOpen(func() {
 		printDataChannel(dataChannel)
 		trace("Dial: Data Channel OnOpen")
+
+		conn.raw, err = dataChannel.Detach()
+		if err != nil {
+			conn.pushErrorData(err)
+		} else {
 			conn.dataChannel = dataChannel
 			connFinish <- true
+		}
 	})
 
-	// Register text message handling
-	dataChannel.OnMessage(func(msg webrtc.DataChannelMessage) {
-		// log.Print("Client: Received Msg from DataChannel", len(msg.Data))
-		if msg.IsString {
-			trace("Dial: DataChannel OnMessage: Received string message, skipping")
-			return
-		}
-		conn.pushReadData(msg.Data)
-	})
+	// Note: Stopped using this now that I have detached data channels
+	// // Register text message handling
+	// dataChannel.OnMessage(func(msg webrtc.DataChannelMessage) {
+	// 	// log.Print("Client: Received Msg from DataChannel", len(msg.Data))
+	// 	if msg.IsString {
+	// 		trace("Dial: DataChannel OnMessage: Received string message, skipping")
+	// 		return
+	// 	}
+	// 	conn.pushReadData(msg.Data)
+	// })
 
 	// Create an offer to send to the other process
 	offer, err := peerConnection.CreateOffer(nil)

listener.go

@@ -78,6 +78,8 @@ func (l *Listener) Addr() net.Addr {
 func (l *Listener) attemptWebRtcNegotiation(wsConn net.Conn) {
 	defer trace("finished attemptWebRtcNegotiation")
 
+	api := getSettingsEngineApi()
+
 	var candidatesMux sync.Mutex
 	pendingCandidates := make([]*webrtc.ICECandidate, 0)
 	config := webrtc.Configuration{
@@ -88,7 +90,7 @@ func (l *Listener) attemptWebRtcNegotiation(wsConn net.Conn) {
 		},
 	}
 
-	peerConnection, err := webrtc.NewPeerConnection(config)
+	peerConnection, err := api.NewPeerConnection(config)
 	if err != nil {
 		l.pendingAcceptErrors <- err
 		return
@@ -149,7 +151,13 @@ func (l *Listener) attemptWebRtcNegotiation(wsConn net.Conn) {
 		d.OnOpen(func() {
 			printDataChannel(d)
 			wsConn.Close()
+
+			conn.raw, err = d.Detach()
+			if err != nil {
+				l.pendingAcceptErrors <- err
+			} else {
 				l.pendingAccepts <- conn
+			}
 		})
 
 		// // Register channel opening handling
@@ -157,15 +165,16 @@ func (l *Listener) attemptWebRtcNegotiation(wsConn net.Conn) {
 		// 	trace("Listener: Data channel was closed!")
 		// })
 
-		// Register text message handling
-		d.OnMessage(func(msg webrtc.DataChannelMessage) {
-			// log.Print("Server: Received Msg from DataChannel", len(msg.Data))
-			if msg.IsString {
-				trace("Listener: DataChannel OnMessage: Received string message, skipping")
-				return
-			}
-			conn.pushReadData(msg.Data)
-		})
+		// Note: Stopped using this now that I have detached data channels
+		// // Register text message handling
+		// d.OnMessage(func(msg webrtc.DataChannelMessage) {
+		// 	// log.Print("Server: Received Msg from DataChannel", len(msg.Data))
+		// 	if msg.IsString {
+		// 		trace("Listener: DataChannel OnMessage: Received string message, skipping")
+		// 		return
+		// 	}
+		// 	conn.pushReadData(msg.Data)
+		// })
 	})
 
 	buf := make([]byte, 8 * 1024) // TODO: hardcoded to be big enough for the signalling messages

rtcnet.go

@@ -8,7 +8,6 @@ import (
 
 // Notes: https://webrtcforthecurious.com/docs/01-what-why-and-how/
 // Notes: about reliability: https://stackoverflow.com/questions/54292824/webrtc-channel-reliability
-// TODO - Investigate Detaching the datachannel: https://github.com/pion/webrtc/tree/master/examples/data-channels-detach
 // TODO - Let stun server list be injectable
 
 // TODO - Interesting note: if you run this in a docker container with the networking set to something other than "host" (ie the default is bridge), then what happens is the docker container gets NAT'ed behind the original host which causes you to need an ICE server. So You must run this code with HOST networking!!!
@@ -17,6 +16,14 @@ import (
 // - TODO - There might be some way to avoid this with: https://pkg.go.dev/github.com/pion/webrtc/v3#SettingEngine.SetNAT1To1IPs
 // - TODO - also this: https://pkg.go.dev/github.com/pion/webrtc/v3#SettingEngine.SetICEUDPMux
 
+// Current settings engine settings
+// Detaching the datachannel: https://github.com/pion/webrtc/tree/master/examples/data-channels-detach
+func getSettingsEngineApi() *webrtc.API {
+	s := webrtc.SettingEngine{}
+	s.DetachDataChannels()
+	return webrtc.NewAPI(webrtc.WithSettingEngine(s))
+}
+
 // Internal messages used for webrtc negotiation/signalling
 type signalMsg struct {
 	SDP *sdpMsg