直播：PLI 关键帧请求、观众 RTCP 读取、断线自动重连

Made-with: Cursor

server/pkg/weblive/hub.go

@@ -168,9 +168,19 @@ func (h *Hub) attachForwardersToViewerPC(v *viewerSession) {
 		if err != nil {
 			continue
 		}
-		if _, err := v.pc.AddTrack(lt); err != nil {
+		rtpSender, err := v.pc.AddTrack(lt)
+		if err != nil {
 			continue
 		}
+		// Drain RTCP feedback to keep interceptors/senders healthy.
+		go func() {
+			rtcpBuf := make([]byte, 1500)
+			for {
+				if _, _, e := rtpSender.Read(rtcpBuf); e != nil {
+					return
+				}
+			}
+		}()
 		tf.addViewer(v.id, lt)
 	}
 }

server/pkg/weblive/ws.go

@@ -5,12 +5,14 @@ import (
 	"log"
 	"net/http"
 	"sync"
+	"time"
 
 	"yh_web/server/handlers"
 
 	"github.com/gin-gonic/gin"
 	"github.com/google/uuid"
 	"github.com/gorilla/websocket"
+	"github.com/pion/rtcp"
 	"github.com/pion/webrtc/v3"
 )
 
@@ -117,6 +119,20 @@ func handlePublisherWS(c *gin.Context, h *Hub) {
 	pc.OnTrack(func(track *webrtc.TrackRemote, _ *webrtc.RTPReceiver) {
 		log.Printf("weblive: publisher track kind=%s", track.Kind().String())
 		h.onPublisherTrack(track)
+		if track.Kind() == webrtc.RTPCodecTypeVideo {
+			go func(ssrc uint32) {
+				_ = pc.WriteRTCP([]rtcp.Packet{&rtcp.PictureLossIndication{MediaSSRC: ssrc}})
+				ticker := time.NewTicker(2 * time.Second)
+				defer ticker.Stop()
+				for range ticker.C {
+					st := pc.ConnectionState()
+					if st == webrtc.PeerConnectionStateClosed || st == webrtc.PeerConnectionStateFailed {
+						return
+					}
+					_ = pc.WriteRTCP([]rtcp.Packet{&rtcp.PictureLossIndication{MediaSSRC: ssrc}})
+				}
+			}(uint32(track.SSRC()))
+		}
 	})
 
 	pc.OnConnectionStateChange(func(s webrtc.PeerConnectionState) {

web/src/utils/liveWebRTC.js

@@ -78,6 +78,28 @@ export function startViewing(videoEl, opts = {}) {
     }, 6000)
   }
 
+  function rebuildPeer() {
+    try {
+      pc.close()
+    } catch (_) {}
+    pc = newPeer((e) => {
+      if (videoEl && e.streams[0]) {
+        videoEl.srcObject = e.streams[0]
+      }
+    })
+  }
+
+  function resumePollingAfterDisconnect(tip) {
+    if (stopped) return
+    clearBlackFrameTimer()
+    if (videoEl) videoEl.srcObject = null
+    if (tip) onStatus(tip)
+    if (pollTimer) return
+    rebuildPeer()
+    pollTimer = setInterval(poll, pollMs)
+    poll()
+  }
+
   async function negotiate() {
     if (stopped) return
     const icePending = []
@@ -118,33 +140,21 @@ export function startViewing(videoEl, opts = {}) {
         } catch (_) {}
       }
       if (msg.type === 'ended') {
-        clearBlackFrameTimer()
-        onStatus(msg.message || '直播已结束')
-        if (videoEl) videoEl.srcObject = null
         onEnded()
         try {
           ws?.close()
         } catch (_) {}
         ws = null
-        try {
-          pc.close()
-        } catch (_) {}
-        pc = newPeer((e) => {
-          if (videoEl && e.streams[0]) {
-            videoEl.srcObject = e.streams[0]
-          }
-        })
-        if (!stopped && !pollTimer) {
-          pollTimer = setInterval(poll, pollMs)
-          poll()
-        }
+        resumePollingAfterDisconnect(msg.message || '直播已结束')
       }
       if (msg.type === 'error') {
         onStatus(msg.message || '错误')
       }
     }
     ws.onclose = () => {
-      if (!stopped) onStatus('连接已断开')
+      if (stopped) return
+      ws = null
+      resumePollingAfterDisconnect('连接已断开，正在尝试重连…')
     }
   }
 
@@ -175,9 +185,11 @@ export function startViewing(videoEl, opts = {}) {
     stopped = true
     clearBlackFrameTimer()
     if (pollTimer) clearInterval(pollTimer)
+    pollTimer = null
     try {
       ws?.close()
     } catch (_) {}
+    ws = null
     pc.close()
     if (videoEl) videoEl.srcObject = null
   }