adjust try/catch/finally for semaphore release

MareSynchronosServer/MareSynchronosStaticFilesServer/Controllers/RequestController.cs

@@ -23,6 +23,8 @@ public class RequestController : ControllerBase
     [HttpPost]
     [Route(MareFiles.Request_Enqueue)]
     public async Task<IActionResult> PreRequestFilesAsync([FromBody] List<string> files)
+    {
+        try
         {
             await _parallelRequestSemaphore.WaitAsync(HttpContext.RequestAborted);
             foreach (var file in files)
@@ -31,39 +33,57 @@ public class RequestController : ControllerBase
                 _cachedFileProvider.DownloadFileWhenRequired(file, Authorization);
             }
 
-        _parallelRequestSemaphore.Release();
             return Ok();
         }
+        catch (OperationCanceledException) { return BadRequest(); }
+        finally
+        {
+            _parallelRequestSemaphore.Release();
+        }
+    }
 
     [HttpGet]
     [Route(MareFiles.Request_RequestFile)]
     public async Task<IActionResult> RequestFile(string file)
+    {
+        try
         {
             await _parallelRequestSemaphore.WaitAsync(HttpContext.RequestAborted);
             Guid g = Guid.NewGuid();
             _cachedFileProvider.DownloadFileWhenRequired(file, Authorization);
             var queueStatus = await _requestQueue.EnqueueUser(new(g, MareUser, file));
-        _parallelRequestSemaphore.Release();
             return Ok(JsonSerializer.Serialize(new QueueRequestDto(g, queueStatus)));
         }
+        catch (OperationCanceledException) { return BadRequest(); }
+        finally
+        {
+            _parallelRequestSemaphore.Release();
+        }
+    }
 
     [HttpGet]
     [Route(MareFiles.Request_CheckQueue)]
     public async Task<IActionResult> CheckQueueAsync(Guid requestId)
+    {
+        try
         {
             await _parallelRequestSemaphore.WaitAsync(HttpContext.RequestAborted);
             if (_requestQueue.IsActiveProcessing(requestId, MareUser, out _))
             {
-            _parallelRequestSemaphore.Release();
                 return Ok();
             }
 
             if (_requestQueue.StillEnqueued(requestId, MareUser, out int position))
             {
-            _parallelRequestSemaphore.Release();
                 return Conflict(position);
             }
 
             return BadRequest();
         }
+        catch (OperationCanceledException) { return BadRequest(); }
+        finally
+        {
+            _parallelRequestSemaphore.Release();
+        }
+    }
 }