fix: 尝试去修复后端无法停止扫描数码管的问题

server/src/Hubs/DigitalTubesHub.cs

@@ -8,6 +8,8 @@ using DotNext;
 using Peripherals.SevenDigitalTubesClient;
 using System.Collections.Concurrent;
 
+#pragma warning disable 1998
+
 namespace server.Hubs;
 
 [Hub]
@@ -16,7 +18,7 @@ public interface IDigitalTubesHub
     Task<bool> StartScan();
     Task<bool> StopScan();
     Task<bool> SetFrequency(int frequency);
-    Task<DigitalTubeTaskStatus> GetStatus();
+    Task<DigitalTubeTaskStatus?> GetStatus();
 }
 
 [Receiver]
@@ -31,23 +33,27 @@ public class DigitalTubeTaskStatus
     public int Frequency { get; set; } = 100;
     public bool IsRunning { get; set; } = false;
 
-    public DigitalTubeTaskStatus(DigitalTubeInfo info)
+    public DigitalTubeTaskStatus(ScanTaskInfo info)
     {
         Frequency = info.Frequency;
         IsRunning = info.IsRunning;
     }
 }
 
-public class DigitalTubeInfo
+public class ScanTaskInfo
 {
+    public string BoardID { get; set; }
     public string ClientID { get; set; }
+    public Task? ScanTask { get; set; }
     public SevenDigitalTubesCtrl TubeClient { get; set; }
-    public CancellationTokenSource CTS { get; set; } = new CancellationTokenSource();
+    public CancellationTokenSource CTS { get; set; } = new();
     public int Frequency { get; set; } = 100;
     public bool IsRunning { get; set; } = false;
 
-    public DigitalTubeInfo(string clientID, SevenDigitalTubesCtrl client)
+    public ScanTaskInfo(
+        string boardID, string clientID, SevenDigitalTubesCtrl client)
     {
+        BoardID = boardID;
         ClientID = clientID;
         TubeClient = client;
     }
@@ -58,11 +64,10 @@ public class DigitalTubeInfo
 public class DigitalTubesHub : Hub<IDigitalTubesReceiver>, IDigitalTubesHub
 {
     private static NLog.Logger logger = NLog.LogManager.GetCurrentClassLogger();
-
     private readonly IHubContext<DigitalTubesHub, IDigitalTubesReceiver> _hubContext;
     private readonly Database.UserManager _userManager = new();
 
-    private ConcurrentDictionary<string, DigitalTubeInfo> _infoDict = new();
+    private ConcurrentDictionary<(string, string), ScanTaskInfo> _scanTasks = new();
 
     public DigitalTubesHub(IHubContext<DigitalTubesHub, IDigitalTubesReceiver> hubContext)
     {
@@ -95,17 +100,18 @@ public class DigitalTubesHub : Hub<IDigitalTubesReceiver>, IDigitalTubesHub
         return boardRet.Value.Value;
     }
 
-    private Task ScanAllTubes(DigitalTubeInfo info)
+    private Task ScanAllTubes(ScanTaskInfo scanInfo)
     {
+        var token = scanInfo.CTS.Token;
         return Task.Run(async () =>
         {
             var cntError = 0;
-            while (!info.CTS.IsCancellationRequested)
+            while (!token.IsCancellationRequested)
             {
                 var beginTime = DateTime.Now;
-                var waitTime = TimeSpan.FromMilliseconds(1000 / info.Frequency);
+                var waitTime = TimeSpan.FromMilliseconds(1000 / scanInfo.Frequency);
 
-                var dataRet = await info.TubeClient.ScanAllTubes();
+                var dataRet = await scanInfo.TubeClient.ScanAllTubes();
                 if (!dataRet.IsSuccessful)
                 {
                     logger.Error($"Failed to scan tubes: {dataRet.Error}");
@@ -113,126 +119,138 @@ public class DigitalTubesHub : Hub<IDigitalTubesReceiver>, IDigitalTubesHub
                     if (cntError > 3)
                     {
                         logger.Error($"Too many errors, stopping scan");
-                        info.IsRunning = false;
+                        break;
                     }
                 }
-                await _hubContext.Clients.Client(info.ClientID).OnReceive(dataRet.Value);
+                await _hubContext.Clients.Client(scanInfo.ClientID).OnReceive(dataRet.Value);
 
                 var processTime = DateTime.Now - beginTime;
                 if (processTime < waitTime)
                 {
-                    await Task.Delay(waitTime - processTime);
+                    await Task.Delay(waitTime - processTime, token);
                 }
             }
-        }, info.CTS.Token);
+            scanInfo.IsRunning = false;
+        }, token)
+        .ContinueWith((task) =>
+        {
+            if (task.IsFaulted)
+            {
+                logger.Error(
+                    $"Digital tubes scan operation failesj for board {task.Exception}");
+            }
+            else if (task.IsCanceled)
+            {
+                logger.Info(
+                    $"Digital tubes scan operation cancelled for board {scanInfo.BoardID}");
+            }
+            else
+            {
+                logger.Info(
+                    $"Digital tubes scan completed successfully for board {scanInfo.BoardID}");
+            }
+        });
     }
 
-    public Task<bool> StartScan()
+    public async Task<bool> StartScan()
     {
         try
         {
             var board = TryGetBoard().OrThrow(() => new Exception("Board not found"));
-            if (_infoDict.GetOrAdd(
-                board.ID.ToString(),
-                (_) => new DigitalTubeInfo(
-                    Context.ConnectionId,
-                    new SevenDigitalTubesCtrl(board.IpAddr, board.Port, 2))
-            ) is DigitalTubeInfo info)
-            {
-                if (!info.IsRunning)
-                {
-                    info.IsRunning = true;
-                    if (info.CTS.IsCancellationRequested)
-                    {
-                        info.CTS.Dispose();
-                        info.CTS = new CancellationTokenSource();
-                    }
-                    _ = ScanAllTubes(info);
-                }
-            }
+            var key = (board.ID.ToString(), Context.ConnectionId);
 
-            return Task.FromResult(true);
+            if (_scanTasks.TryGetValue(key, out var existing) && existing.IsRunning)
+                return true;
+
+            var cts = new CancellationTokenSource();
+            var scanTaskInfo = new ScanTaskInfo(
+                board.ID.ToString(), Context.ConnectionId,
+                new SevenDigitalTubesCtrl(board.IpAddr, board.Port, 0)
+            );
+            scanTaskInfo.ScanTask = ScanAllTubes(scanTaskInfo);
+
+            _scanTasks[key] = scanTaskInfo;
+            return true;
         }
         catch (Exception ex)
         {
             logger.Error(ex, "Failed to start scan");
-            return Task.FromResult(false);
+            return false;
         }
     }
 
-    public Task<bool> StopScan()
+    public async Task<bool> StopScan()
     {
         try
         {
             var board = TryGetBoard().OrThrow(() => new Exception("Board not found"));
-            if (_infoDict.GetOrAdd(
-                board.ID.ToString(),
-                (_) => new DigitalTubeInfo(
-                    Context.ConnectionId,
-                    new SevenDigitalTubesCtrl(board.IpAddr, board.Port, 2))
-            ) is DigitalTubeInfo info)
-            {
-                info.IsRunning = false;
-                info.CTS.Cancel();
-            }
+            var key = (board.ID.ToString(), Context.ConnectionId);
 
-            return Task.FromResult(true);
+            if (_scanTasks.TryRemove(key, out var scanInfo))
+            {
+                scanInfo.IsRunning = false;
+                scanInfo.CTS.Cancel();
+                if (scanInfo.ScanTask != null)
+                    await scanInfo.ScanTask;
+                scanInfo.CTS.Dispose();
+            }
+            return true;
         }
         catch (Exception ex)
         {
             logger.Error(ex, "Failed to stop scan");
-            return Task.FromResult(false);
+            return false;
         }
     }
 
-    public Task<bool> SetFrequency(int frequency)
+    public async Task<bool> SetFrequency(int frequency)
     {
         try
         {
-            if (frequency < 1 || frequency > 1000) return Task.FromException<bool>(
-                new ArgumentException("Frequency must be between 1 and 1000"));
+            if (frequency < 1 || frequency > 1000)
+                return false;
 
             var board = TryGetBoard().OrThrow(() => new Exception("Board not found"));
-            if (_infoDict.GetOrAdd(
-                board.ID.ToString(),
-                (_) => new DigitalTubeInfo(
-                    Context.ConnectionId,
-                    new SevenDigitalTubesCtrl(board.IpAddr, board.Port, 2))
-            ) is DigitalTubeInfo info)
-            {
-                info.Frequency = frequency;
-            }
+            var key = (board.ID.ToString(), Context.ConnectionId);
 
-            return Task.FromResult(true);
+            if (_scanTasks.TryGetValue(key, out var scanInfo) && scanInfo.IsRunning)
+            {
+                scanInfo.Frequency = frequency;
+                return true;
+            }
+            else
+            {
+                logger.Warn($"SetFrequency called but no running scan for board {board.ID} and client {Context.ConnectionId}");
+                return false;
+            }
         }
         catch (Exception ex)
         {
             logger.Error(ex, "Failed to set frequency");
-            return Task.FromResult(false);
+            return false;
         }
     }
 
-    public Task<DigitalTubeTaskStatus> GetStatus()
+    public async Task<DigitalTubeTaskStatus?> GetStatus()
     {
         try
         {
             var board = TryGetBoard().OrThrow(() => new Exception("Board not found"));
-            if (_infoDict.GetOrAdd(
-                board.ID.ToString(),
-                (_) => new DigitalTubeInfo(
-                    Context.ConnectionId,
-                    new SevenDigitalTubesCtrl(board.IpAddr, board.Port, 2))
-            ) is DigitalTubeInfo info)
-            {
-                return Task.FromResult(new DigitalTubeTaskStatus(info));
-            }
+            var key = (board.ID.ToString(), Context.ConnectionId);
 
-            return Task.FromException<DigitalTubeTaskStatus>(new ArgumentException("Wrong argument"));
+            if (_scanTasks.TryGetValue(key, out var scanInfo))
+            {
+                return new DigitalTubeTaskStatus(scanInfo);
+            }
+            else
+            {
+                return null;
+            }
         }
         catch (Exception ex)
         {
             logger.Error(ex, "Failed to get status");
-            return Task.FromException<DigitalTubeTaskStatus>(new Exception("Failed to get status"));
+            throw new Exception("Failed to get status", ex);
         }
     }