Make STUN server configurable

docs/ghostream.example.yml

@@ -10,7 +10,7 @@ auth:
 
   # Example to bypass login, dangerous!
   #backend: bypass
-
+  #
   # Example of LDAP server login
   #backend: ldap
   #ldap:
@@ -41,3 +41,7 @@ webrtc:
   # UDP port range used to stream
   minPortUDP: 10000
   maxPortUDP: 10005
+
+  # STUN servers, you should host your own Coturn instance
+  STUNServers:
+    - stun:stun.l.google.com:19302

main.go

@@ -55,6 +55,10 @@ func loadConfiguration() {
 	viper.SetDefault("Web.Favicon", "/favicon.ico")
 	viper.SetDefault("WebRTC.MinPortUDP", 10000)
 	viper.SetDefault("WebRTC.MaxPortUDP", 10005)
+	viper.SetDefault("WebRTC.STUNServers", []string{"stun:stun.l.google.com:19302"})
+
+	// Copy STUN configuration to clients
+	viper.Set("Web.STUNServers", viper.Get("WebRTC.STUNServers"))
 }
 
 func main() {

stream/webrtc/webrtc.go

@@ -18,6 +18,8 @@ import (
 type Options struct {
 	MinPortUDP uint16
 	MaxPortUDP uint16
+
+	STUNServers []string
 }
 
 // SessionDescription contains SDP data
@@ -65,11 +67,7 @@ func newPeerHandler(remoteSdp webrtc.SessionDescription, cfg *Options) webrtc.Se
 		webrtc.WithSettingEngine(settingsEngine),
 	)
 	peerConnection, err := api.NewPeerConnection(webrtc.Configuration{
-		ICEServers: []webrtc.ICEServer{
-			{
-				URLs: []string{"stun:stun.l.google.com:19302"},
-			},
-		},
+		ICEServers: []webrtc.ICEServer{{URLs: cfg.STUNServers}},
 	})
 	if err != nil {
 		log.Println("Failed to initiate peer connection", err)

web/static/js/viewer.js

@@ -3,12 +3,7 @@ let peerConnection;
 startPeerConnection = () => {
     // Init peer connection
     peerConnection = new RTCPeerConnection({
-        iceServers: [
-            {
-                // FIXME: let admin customize the stun server
-                urls: 'stun:stun.l.google.com:19302'
-            }
-        ]
+        iceServers: [{ urls: stunServers }]
     })
 
     // On connection change, change indicator color
@@ -80,6 +75,3 @@ startPeerConnection = () => {
         }
     }
 }
-
-// Start
-startPeerConnection()

web/template/viewer.html

@@ -36,4 +36,12 @@
 
 <script src="/static/js/sideWidget.js"></script>
 <script src="/static/js/viewer.js"></script>
+<script>
+  const stunServers = [
+    {{range $id, $value := .Cfg.STUNServers}}
+    '{{$value}}',
+    {{end}}
+  ]
+  startPeerConnection()
+</script>
 {{end}}

web/web.go

@@ -20,6 +20,9 @@ type Options struct {
 	Hostname      string
 	Favicon       string
 	WidgetURL     string
+
+	// Copied from WebRTC configuration
+	STUNServers []string
 }
 
 var (