From d4f30c126f3110490adbb6e8b38e3cc3bc0e6875 Mon Sep 17 00:00:00 2001
From: David Zhao <david@davidzhao.com>
Date: Sat, 5 Dec 2020 23:36:45 -0800
Subject: [PATCH] Fix node IP discovery, force to ipv4

---
 README.md                 | 17 ++++++++++++++---
 cmd/cli/commands/utils.go |  2 +-
 pkg/node/node.go          | 40 +++++++++++++++++++++++++++++----------
 3 files changed, 45 insertions(+), 14 deletions(-)

diff --git a/README.md b/README.md
index f7f1a6f41..3813fa565 100644
--- a/README.md
+++ b/README.md
@@ -24,13 +24,24 @@ To run a peer publishing to a room, do the following:
 2. Create a room
 
     ```
-    ./bin/livekit-cli create-room --room-id hello
+    ./bin/livekit-cli create-room
     ```
+   
+   It'll print out something like this. note the room id
+
+   ```json
+      {
+        "sid": "RM_CkjigXb6oZQyZ4JNFZqBen",
+        "node_ip": "98.35.19.21",
+        "creation_time": 1607240104,
+        "token": "b9e8c9f6-fbb3-46d5-b6fc-5517186510a6"
+      }
+   ```
 
 3. Join room as publishing client
 
    ```
-   ./ bin/livekit-cli join --room-id hello --audio <path/to/ogg> --video <path/to/ivf>
+   ./ bin/livekit-cli join --audio <path/to/ogg> --video <path/to/ivf> --room-id <room_sid>
    ```
 
 That's it, join the room with another peer id and see it receiving those tracks
@@ -48,7 +59,7 @@ see `rtc.proto` for the message structure.
 
 The flow for interaction is:
 1. Establish WebSocket to ws://<host>:<port>/rtc
-1. Server will send back a `SignalResponse` with a `join` response. It'll include the new participant's details (and in the future, room info)
+1. Server will send back a `SignalResponse` with a `join` response. It'll include the new participant's details, and what other participants are in the room
 1. Client sends a `SignalRequest` with an WebRTC `offer`
 1. Server will send back a `SignalResponse` with an `answer`
 1. Client and server will exchange ice candidates via `trickle` in the request & responses
diff --git a/cmd/cli/commands/utils.go b/cmd/cli/commands/utils.go
index 0fae82411..5266ea026 100644
--- a/cmd/cli/commands/utils.go
+++ b/cmd/cli/commands/utils.go
@@ -26,7 +26,7 @@ var (
 )
 
 func PrintJSON(obj interface{}) {
-	txt, _ := json.Marshal(obj)
+	txt, _ := json.MarshalIndent(obj, "", "  ")
 	fmt.Println(string(txt))
 }
 
diff --git a/pkg/node/node.go b/pkg/node/node.go
index 1dfd8d384..f3cc8edbc 100644
--- a/pkg/node/node.go
+++ b/pkg/node/node.go
@@ -1,18 +1,19 @@
 package node
 
 import (
-	"errors"
+	"context"
+	"fmt"
+	"time"
 
 	"github.com/google/wire"
 	"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"
 )
 
-const ()
-
 var NodeSet = wire.NewSet(NewLocalNode)
 
 type Node struct {
@@ -46,7 +47,7 @@ func (n *Node) DiscoverNetworkInfo() error {
 	if len(n.config.RTC.StunServers) == 0 {
 		return errors.New("STUN servers are required but not defined")
 	}
-	c, err := stun.Dial("udp", n.config.RTC.StunServers[0])
+	c, err := stun.Dial("udp4", n.config.RTC.StunServers[0])
 	if err != nil {
 		return err
 	}
@@ -58,7 +59,7 @@ func (n *Node) DiscoverNetworkInfo() error {
 	}
 
 	var stunErr error
-	err = c.Do(message, func(res stun.Event) {
+	err = c.Start(message, func(res stun.Event) {
 		if res.Error != nil {
 			stunErr = res.Error
 			return
@@ -69,11 +70,30 @@ func (n *Node) DiscoverNetworkInfo() error {
 			stunErr = err
 			return
 		}
-		n.Ip = xorAddr.IP.String()
+		ip := xorAddr.IP.To4()
+		if ip != nil {
+			n.Ip = ip.String()
+		}
 	})
-
-	if stunErr != nil {
-		err = stunErr
+	if err != nil {
+		return err
 	}
-	return err
+
+	ctx, cancel := context.WithTimeout(context.Background(), 5*time.Second)
+	defer cancel()
+	for n.Ip == "" {
+		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 nil
 }