重命名客户端相关术语为节点；移动 utils 包到根路径；优化网关对节点各种连接状态的处理，并在节点断联后统一清理资源

gateway/fwd/ctrl.go

@@ -12,8 +12,9 @@ import (
 	"proxy-server/gateway/app"
 	"proxy-server/gateway/env"
 	"proxy-server/gateway/report"
-	"proxy-server/pkg/utils"
+	"proxy-server/utils"
 	"strconv"
+	"syscall"
 )
 
 type CtrlCmdType int
@@ -80,6 +81,21 @@ func (s *Service) listenCtrl() error {
 }
 
 func (s *Service) processCtrlConn(ctx context.Context, conn net.Conn) (err error) {
+	defer func() {
+		_, portStr, err := net.SplitHostPort(conn.LocalAddr().String())
+		if err != nil {
+			slog.Error("获取控制通道端口失败", "err", err)
+			return
+		}
+
+		port, err := strconv.ParseUint(portStr, 10, 16)
+		if err != nil {
+			slog.Error("解析控制通道端口失败", "err", err)
+			return
+		}
+
+		app.DelEdge(uint16(port))
+	}()
 	reader := bufio.NewReader(conn)
 	for {
 		// 循环等待直到服务关闭
@@ -90,12 +106,21 @@ func (s *Service) processCtrlConn(ctx context.Context, conn net.Conn) (err error
 		}
 
 		// 读取命令
-		cmdByte, err := reader.ReadByte()
+		cmd, err := reader.ReadByte()
+		if errors.Is(err, syscall.WSAECONNRESET) {
+			slog.Debug("节点重置了控制通道连接(WSAECONNRESET)")
+			return nil
+		}
+		if errors.Is(err, io.EOF) {
+			slog.Debug("节点关闭了控制通道")
+			return nil
+		}
 		if err != nil {
 			return fmt.Errorf("读取节点命令失败: %w", err)
 		}
-		var cmd = CtrlCmdType(cmdByte)
-		switch cmd {
+
+		// 处理节点命令
+		switch CtrlCmdType(cmd) {
 
 		// 连接建立命令
 		case CtrlCmdOpen:
@@ -132,15 +157,11 @@ func (s *Service) processCtrlConn(ctx context.Context, conn net.Conn) (err error
 	}
 }
 
-func (s *Service) onPing(conn net.Conn) (err error) {
-	return s.sendPong(conn)
-}
-
-func (s *Service) onOpen(conn net.Conn, client int32) (err error) {
+func (s *Service) onOpen(writer io.Writer, edge int32) (err error) {
 	// open 命令全局只执行一次
-	_, ok := app.Clients.Load(client)
+	_, ok := app.Edges.Load(edge)
 	if ok {
-		return fmt.Errorf("节点 ID %d 已经连接", client)
+		return fmt.Errorf("节点 ID %d 已经连接", edge)
 	}
 
 	// 分配端口
@@ -151,8 +172,7 @@ func (s *Service) onOpen(conn net.Conn, client int32) (err error) {
 		var _, ok = app.Assigns.Load(i)
 		if !ok {
 			port = i
-			app.Assigns.Store(i, client)
-			app.Clients.Store(client, i)
+			app.AddEdge(edge, port)
 			break
 		}
 	}
@@ -161,62 +181,46 @@ func (s *Service) onOpen(conn net.Conn, client int32) (err error) {
 	}
 
 	// 报告端口分配
-	if err = report.Assigned(client, port); err != nil {
+	if err = report.Assigned(edge, port); err != nil {
 		return fmt.Errorf("报告端口分配失败: %w", err)
 	}
 
-	// 响应客户端
-	if err = s.sendPong(conn); err != nil {
-		return fmt.Errorf("响应客户端失败: %w", err)
+	// 响应节点
+	if err = s.sendPong(writer); err != nil {
+		return fmt.Errorf("响应节点失败: %w", err)
 	}
 
 	// 启动转发服务
 	s.fwdLesWg.Add(1)
 	go func() {
 		defer s.fwdLesWg.Done()
-		slog.Info("监听转发端口", "port", port, "client", client)
-		err = s.listenUser(port, conn)
+		slog.Info("监听转发端口", "port", port, "edge", edge)
+		err = s.listenUser(port, writer)
 		if err != nil {
-			slog.Error("监听转发端口失败", "port", port, "client", client, "err", err)
+			slog.Error("监听转发端口失败", "port", port, "edge", edge, "err", err)
 		}
 	}()
 
 	return nil
 }
 
-func (s *Service) onClose(conn net.Conn) (err error) {
-	_, portStr, err := net.SplitHostPort(conn.LocalAddr().String())
-	if err != nil {
-		return err
-	}
-
-	port, err := strconv.ParseUint(portStr, 10, 16)
-	if err != nil {
-		return err
-	}
-
-	id, _ := app.Assigns.LoadAndDelete(uint16(port))
-	app.Clients.Delete(id)
-	app.Assigns.Delete(uint16(port))
-	app.Permits.Delete(uint16(port))
-
-	err = s.sendPong(conn)
-	if err != nil {
-		return err
-	}
-
-	return nil
+func (s *Service) onPing(writer io.Writer) (err error) {
+	return s.sendPong(writer)
 }
 
-func (s *Service) sendPong(conn net.Conn) (err error) {
-	_, err = conn.Write([]byte{byte(CtrlCmdPong)})
+func (s *Service) onClose(writer io.Writer) (err error) {
+	return s.sendPong(writer)
+}
+
+func (s *Service) sendPong(writer io.Writer) (err error) {
+	_, err = writer.Write([]byte{byte(CtrlCmdPong)})
 	if err != nil {
-		return fmt.Errorf("响应客户端失败: %w", err)
+		return fmt.Errorf("响应节点失败: %w", err)
 	}
 	return nil
 }
 
-func (s *Service) sendProxy(conn net.Conn, tag [16]byte, addr string) (err error) {
+func (s *Service) sendProxy(writer io.Writer, tag [16]byte, addr string) (err error) {
 	if len(addr) > 65535 {
 		return fmt.Errorf("代理地址过长: %s", addr)
 	}
@@ -227,7 +231,7 @@ func (s *Service) sendProxy(conn net.Conn, tag [16]byte, addr string) (err error
 	binary.BigEndian.PutUint16(buf[17:], uint16(len(addr)))
 	copy(buf[19:], addr)
 
-	_, err = conn.Write(buf)
+	_, err = writer.Write(buf)
 	if err != nil {
 		return fmt.Errorf("发送代理命令失败: %w", err)
 	}