From aa177583e055a6dafaaee53c6ad18df526241652 Mon Sep 17 00:00:00 2001
From: rootdarkarchon <root.darkarchon@outlook.com>
Date: Sat, 14 Jan 2023 12:57:34 +0100
Subject: [PATCH] sanitize queue processing

---
 .../Services/RequestQueueService.cs           | 73 ++++++++++++-------
 1 file changed, 48 insertions(+), 25 deletions(-)

diff --git a/MareSynchronosServer/MareSynchronosStaticFilesServer/Services/RequestQueueService.cs b/MareSynchronosServer/MareSynchronosStaticFilesServer/Services/RequestQueueService.cs
index c18c665..06c40f5 100644
--- a/MareSynchronosServer/MareSynchronosStaticFilesServer/Services/RequestQueueService.cs
+++ b/MareSynchronosServer/MareSynchronosStaticFilesServer/Services/RequestQueueService.cs
@@ -35,22 +35,34 @@ public class RequestQueueService : IHostedService
             return QueueStatus.Waiting;
         }
 
-        await _queueSemaphore.WaitAsync().ConfigureAwait(false);
-        QueueStatus status = QueueStatus.Waiting;
-        var idx = Array.FindIndex(_userQueueRequests, r => r == null);
-        if (idx == -1)
+        try
         {
-            _queue.Enqueue(request);
-            status = QueueStatus.Waiting;
-        }
-        else
-        {
-            DequeueIntoSlot(request, idx);
-            status = QueueStatus.Ready;
-        }
-        _queueSemaphore.Release();
+            await _queueSemaphore.WaitAsync().ConfigureAwait(false);
+            QueueStatus status = QueueStatus.Waiting;
+            var idx = Array.FindIndex(_userQueueRequests, r => r == null);
+            if (idx == -1)
+            {
+                _queue.Enqueue(request);
+                status = QueueStatus.Waiting;
+            }
+            else
+            {
+                DequeueIntoSlot(request, idx);
+                status = QueueStatus.Ready;
+            }
 
-        return status;
+            return status;
+        }
+        catch (Exception ex)
+        {
+            _logger.LogError(ex, "Error during EnqueueUser");
+        }
+        finally
+        {
+            _queueSemaphore.Release();
+        }
+
+        throw new Exception("Error during EnqueueUser");
     }
 
     public bool StillEnqueued(Guid request, string user, out int queuePosition)
@@ -92,24 +104,35 @@ public class RequestQueueService : IHostedService
     {
         while (!ct.IsCancellationRequested)
         {
-            await _queueProcessingSemaphore.WaitAsync(ct).ConfigureAwait(false);
-            await _queueSemaphore.WaitAsync(ct).ConfigureAwait(false);
-            for (int i = 0; i < _userQueueRequests.Length; i++)
+            try
             {
-                if (_userQueueRequests[i] != null && !_userQueueRequests[i].IsActive && _userQueueRequests[i].ExpirationDate < DateTime.UtcNow) _userQueueRequests[i] = null;
-
-                if (_userQueueRequests[i] == null)
+                await _queueProcessingSemaphore.WaitAsync(ct).ConfigureAwait(false);
+                await _queueSemaphore.WaitAsync(ct).ConfigureAwait(false);
+                for (int i = 0; i < _userQueueRequests.Length; i++)
                 {
-                    if (_queue.TryDequeue(out var request))
+                    if (_userQueueRequests[i] != null && !_userQueueRequests[i].IsActive && _userQueueRequests[i].ExpirationDate < DateTime.UtcNow) _userQueueRequests[i] = null;
+
+                    if (_userQueueRequests[i] == null)
                     {
-                        DequeueIntoSlot(request, i);
+                        if (_queue.TryDequeue(out var request))
+                        {
+                            DequeueIntoSlot(request, i);
+                        }
                     }
+
+                    if (!_queue.Any()) break;
                 }
 
-                if (!_queue.Any()) break;
             }
-            _queueProcessingSemaphore.Release();
-            _queueSemaphore.Release();
+            catch (Exception ex)
+            {
+                _logger.LogError(ex, "Error during Queue processing");
+            }
+            finally
+            {
+                _queueProcessingSemaphore.Release();
+                _queueSemaphore.Release();
+            }
 
             _metrics.SetGaugeTo(MetricsAPI.GaugeDownloadQueue, _queue.Count);