Method proxyMessages

internal/vnc/proxy.go:342–400

proxyMessages handles message forwarding between WebSocket connections.

(src, dst *websocket.Conn, direction, targetName string)

// proxyMessages handles message forwarding between WebSocket connections.
func (p *WebSocketProxy) proxyMessages(src, dst *websocket.Conn, direction, targetName string) error {
	var messageCount int

	// Set initial read deadline
	if deadlineErr := src.SetReadDeadline(time.Now().Add(5 * time.Minute)); deadlineErr != nil {
		p.logger.Debug("Failed to set initial read deadline (%s) for %s: %v", direction, targetName, deadlineErr)
	}

	src.SetPongHandler(func(string) error {
		p.logger.Debug("Pong received (%s) for %s", direction, targetName)

		if deadlineErr := src.SetReadDeadline(time.Now().Add(5 * time.Minute)); deadlineErr != nil {
			p.logger.Debug("Failed to reset read deadline (%s) for %s: %v", direction, targetName, deadlineErr)
		}

		return nil
	})

	for {
		messageType, message, err := src.ReadMessage()
		if err != nil {
			if websocket.IsUnexpectedCloseError(err, websocket.CloseGoingAway, websocket.CloseAbnormalClosure) {
				p.logger.Error("Unexpected close error (%s) for %s: %v", direction, targetName, err)

				return fmt.Errorf("unexpected close error (%s): %w", direction, err)
			}

			p.logger.Debug("Normal close for %s (%s) after %d messages", direction, targetName, messageCount)

			return nil // Normal close
		}

		// Reset read deadline on each message
		if deadlineErr := src.SetReadDeadline(time.Now().Add(5 * time.Minute)); deadlineErr != nil {
			p.logger.Debug("Failed to reset read deadline (%s) for %s: %v", direction, targetName, deadlineErr)
		}

		messageCount++
		if messageCount == 1 {
			p.logger.Debug("First message received (%s) for %s: type=%d, size=%d bytes",
				direction, targetName, messageType, len(message))
		} else if messageCount%100 == 0 {
			p.logger.Debug("Message count (%s) for %s: %d messages processed",
				direction, targetName, messageCount)
		}

		err = dst.WriteMessage(messageType, message)
		if err != nil {
			p.logger.Error("Write error (%s) for %s after %d messages: %v",
				direction, targetName, messageCount, err)

			return fmt.Errorf("write error (%s): %w", direction, err)
		}

		if p.session != nil {
			p.session.UpdateLastUsed()
		}
	}