Configure self-hosted STUN for remote WebRTC

backend/.env.example

@@ -23,7 +23,8 @@ KNOWLEDGE_TOP_K=5
 
 # ---- WebRTC TURN(公网跨网语音预览;本地开发留空) ----
 # 与 docker compose --profile remote 的 coturn 配套。云安全组需放行 UDP 3478 与 49152-49200。
-# PUBLIC_IP 填云主机公网 IP(compose 里给 coturn --external-ip 用,见项目根 .env)。
-# TURN_URLS=turn:182.92.86.220:3478?transport=udp,turn:182.92.86.220:3478?transport=tcp
+# Docker Compose 部署请在项目根 .env 设置这些变量;此处适用于宿主机直接运行 uvicorn。
+# STUN_URL=stun:118.89.89.89:3478
+# TURN_URLS=turn:118.89.89.89:3478?transport=udp,turn:118.89.89.89:3478?transport=tcp
 # TURN_SECRET=your-turn-secret
 # TURN_CREDENTIAL_TTL=86400

backend/services/webrtc_ice.py

@@ -9,8 +9,6 @@ import time
 
 import settings
 
-STUN_URL = "stun:stun.l.google.com:19302"
-
 
 def _turn_credentials() -> tuple[str, str] | None:
     """Return (username, credential) for TURN, or None when TURN is not configured."""
@@ -34,7 +32,7 @@ def _turn_credentials() -> tuple[str, str] | None:
 
 def client_ice_servers() -> list[dict]:
     """ICE servers for browser RTCPeerConnection (JSON-serializable)."""
-    servers: list[dict] = [{"urls": STUN_URL}]
+    servers: list[dict] = [{"urls": settings.STUN_URL}]
     creds = _turn_credentials()
     if not creds:
         return servers
@@ -48,7 +46,7 @@ def aiortc_ice_servers() -> list:
     """ICE servers for backend SmallWebRTCConnection / aiortc."""
     from aiortc import RTCIceServer
 
-    servers = [RTCIceServer(urls=STUN_URL)]
+    servers = [RTCIceServer(urls=settings.STUN_URL)]
     creds = _turn_credentials()
     if not creds:
         return servers

backend/settings.py

@@ -38,9 +38,13 @@ AUTH_TOKEN_EXPIRE_MINUTES = int(os.getenv("AUTH_TOKEN_EXPIRE_MINUTES", "1440"))
 AUTH_COOKIE_SECURE = os.getenv("AUTH_COOKIE_SECURE", "false").lower() == "true"
 AUTH_COOKIE_SAMESITE = os.getenv("AUTH_COOKIE_SAMESITE", "lax")
 
-# ---- WebRTC TURN ----
+# ---- WebRTC STUN / TURN ----
+# Override STUN_URL in remote deployments to use the colocated coturn server
+# instead of waiting for a public STUN service that may be unreachable.
+STUN_URL = os.getenv("STUN_URL", "stun:stun.l.google.com:19302")
+
 # TURN_URLS example:
-# turn:182.92.86.220:3478?transport=udp,turn:182.92.86.220:3478?transport=tcp
+# turn:118.89.89.89:3478?transport=udp,turn:118.89.89.89:3478?transport=tcp
 TURN_URLS = _split(os.getenv("TURN_URLS", ""))
 TURN_SECRET = os.getenv("TURN_SECRET", "")
 TURN_USERNAME = os.getenv("TURN_USERNAME", "")