decouple websocket and RTC nodes, prep for distributed

pkg/routing/node.go

@@ -0,0 +1,93 @@
+package routing
+
+import (
+	"context"
+	"fmt"
+	"runtime"
+	"time"
+
+	"github.com/pion/stun"
+	"github.com/pkg/errors"
+
+	"github.com/livekit/livekit-server/pkg/config"
+	"github.com/livekit/livekit-server/pkg/utils"
+	"github.com/livekit/livekit-server/proto/livekit"
+)
+
+type NodeStats struct {
+	NumRooms         int32
+	NumClients       int32
+	NumVideoChannels int32
+	NumAudioChannels int32
+	BytesPerMin      int64
+}
+
+type LocalNode *livekit.Node
+
+func NewLocalNode(conf *config.Config) (LocalNode, error) {
+	ip, err := GetLocalIP(conf.RTC.StunServers)
+	if err != nil {
+		return nil, err
+	}
+	return &livekit.Node{
+		Id:      utils.NewGuid(utils.NodePrefix),
+		Ip:      ip,
+		NumCpus: uint32(runtime.NumCPU()),
+	}, nil
+}
+
+func GetLocalIP(stunServers []string) (string, error) {
+	if len(stunServers) == 0 {
+		return "", errors.New("STUN servers are required but not defined")
+	}
+	c, err := stun.Dial("udp4", stunServers[0])
+	if err != nil {
+		return "", err
+	}
+	defer c.Close()
+
+	message, err := stun.Build(stun.TransactionID, stun.BindingRequest)
+	if err != nil {
+		return "", err
+	}
+
+	var stunErr error
+	var nodeIp string
+	err = c.Start(message, func(res stun.Event) {
+		if res.Error != nil {
+			stunErr = res.Error
+			return
+		}
+
+		var xorAddr stun.XORMappedAddress
+		if err := xorAddr.GetFrom(res.Message); err != nil {
+			stunErr = err
+			return
+		}
+		ip := xorAddr.IP.To4()
+		if ip != nil {
+			nodeIp = ip.String()
+		}
+	})
+	if err != nil {
+		return "", err
+	}
+
+	ctx, cancel := context.WithTimeout(context.Background(), 5*time.Second)
+	defer cancel()
+	for nodeIp == "" {
+		select {
+		case <-ctx.Done():
+			msg := "could not determine public IP"
+			if stunErr != nil {
+				return "", errors.Wrap(stunErr, msg)
+			} else {
+				return "", fmt.Errorf(msg)
+			}
+		case <-time.After(100 * time.Millisecond):
+			continue
+		}
+	}
+
+	return nodeIp, nil
+}