Fixed bug when frame connection could be lost

cmd/managementd/main.go

@@ -278,66 +278,79 @@ func main() {
 		})
 	})
 
-	go func() {
-		for {
-			err := os.Remove(frameSocket)
-			if err != nil && !os.IsNotExist(err) {
-				log.Printf("Couldn't remove  %v %v\n", frameSocket, err)
-				time.Sleep(1000)
-				continue
-			}
-
-			listener, err := net.Listen("unix", frameSocket)
-			if err != nil {
-				log.Println("Couldn't make socket", err)
-				return
-			}
-			log.Print("waiting for frames from tc2-agent")
-
-			listener.(*net.UnixListener).SetDeadline(time.Now().Add(5 * time.Second))
-			conn, err := listener.Accept()
-			if err != nil {
-				if err.(net.Error).Timeout() {
-					log.Printf("socket accept timed out, retrying...")
+	// Handle the frame listener in a separate goroutine
+	go handleFrameListenerLoop()
 
-					if hasActiveClients() {
-						listener.(*net.UnixListener).SetDeadline(time.Now().Add(30 * time.Second))
-						// If there are users connected via web sockets, force the frames to get served.
-						log.Println("Websocket has clients, forcing frame priority")
-						tc2AgentDbus, err := GetTC2AgentDbus()
-						if err != nil {
-							log.Println(err)
-							return
-						}
-						var result string
-						err = tc2AgentDbus.Call("org.cacophony.TC2Agent.prioritiseframeserve", 0).Store(&result)
-						if err != nil {
-							log.Println(err)
-							return
-						}
-					}
+	listenAddr := fmt.Sprintf(":%d", config.Port)
+	log.Printf("listening on %s", listenAddr)
+	log.Fatal(http.ListenAndServe(listenAddr, router))
+}
 
-					continue
-				}
-				log.Printf("socket accept failed: %v", err)
-				continue
-			}
+func handleFrameListenerLoop() {
+	for {
+		err := handleFrameListener()
+		if err != nil {
+			log.Errorf("Error handling frame listener: %v", err)
+		}
+		log.Info("Will retry connection in 5 seconds")
+		time.Sleep(5 * time.Second)
+	}
+}
 
-			// Prevent concurrent connections.
-			listener.Close()
+func handleFrameListener() error {
+	for {
+		// Remove old frame socket
+		err := os.Remove(frameSocket)
+		if err != nil && !os.IsNotExist(err) {
+			log.Errorf("Couldn't remove frame socket '%s'", frameSocket)
+			return err
+		}
 
-			log.Printf("accepted connection from client")
-			err = handleConn(conn)
-			frameCh <- &FrameData{Disconnected: true}
-			log.Printf("camera connection ended with: %v", err)
-			connected.Store(false)
+		// Make new socket
+		listener, err := net.Listen("unix", frameSocket)
+		if err != nil {
+			log.Errorf("Couldn't make socket '%s'", frameSocket)
+			return err
+		}
 
+		// Prioritise frames if there are active clients
+		log.Info("Waiting for frames from tc2-agent")
+		deadLineDuration := 5 * time.Second
+		if hasActiveClients() {
+			deadLineDuration = 30 * time.Second
+			tc2AgentDbus, err := GetTC2AgentDbus()
+			if err != nil {
+				log.Error("Failed to get TC2AgentDbus")
+				return err
+			}
+			var result string
+			err = tc2AgentDbus.Call("org.cacophony.TC2Agent.prioritiseframeserve", 0).Store(&result)
+			if err != nil {
+				log.Errorf("Failed to request frame serve priority from rp2040, %s", result)
+				return err
+			}
 		}
-	}()
 
-	listenAddr := fmt.Sprintf(":%d", config.Port)
-	log.Printf("listening on %s", listenAddr)
-	log.Fatal(http.ListenAndServe(listenAddr, router))
+		// Wait for and accept connection
+		listener.(*net.UnixListener).SetDeadline(time.Now().Add(deadLineDuration))
+		conn, err := listener.Accept()
+		if err != nil && err.(net.Error).Timeout() {
+			log.Info("Socket accept timed out, retrying...")
+			continue
+		} else if err != nil {
+			log.Errorf("Socket accept failed: %v", err)
+			return err
+		}
+		// Prevent concurrent connections.
+		listener.Close()
+
+		// Handle connection
+		log.Info("Accepted connection from client")
+		err = handleConn(conn)
+		frameCh <- &FrameData{Disconnected: true}
+		log.Infof("Camera connection ended with: %v", err)
+		connected.Store(false)
+	}
 }
 
 func handleConn(conn net.Conn) error {