1 files changed, 20 insertions, 0 deletions
diff --git a/src/csharp/Grpc.Core/Internal/AsyncCallServer.cs b/src/csharp/Grpc.Core/Internal/AsyncCallServer.cs
index f809f4a84c..702f1ce9e7 100644
--- a/src/csharp/Grpc.Core/Internal/AsyncCallServer.cs
+++ b/src/csharp/Grpc.Core/Internal/AsyncCallServer.cs
@@ -48,6 +48,7 @@ namespace Grpc.Core.Internal
     internal class AsyncCallServer<TRequest, TResponse> : AsyncCallBase<TResponse, TRequest>
     {
         readonly TaskCompletionSource<object> finishedServersideTcs = new TaskCompletionSource<object>();
+        readonly CancellationTokenSource cancellationTokenSource = new CancellationTokenSource();
         readonly GrpcEnvironment environment;
 
         public AsyncCallServer(Func<TResponse, byte[]> serializer, Func<byte[], TRequest> deserializer, GrpcEnvironment environment) : base(serializer, deserializer)
@@ -118,6 +119,18 @@ namespace Grpc.Core.Internal
             }
         }
 
+        /// <summary>
+        /// Gets cancellation token that gets cancelled once close completion
+        /// is received and the cancelled flag is set.
+        /// </summary>
+        public CancellationToken CancellationToken
+        {
+            get
+            {
+                return cancellationTokenSource.Token;
+            }
+        }
+
         protected override void OnReleaseResources()
         {
             environment.DebugStats.ActiveServerCalls.Decrement();
@@ -138,6 +151,8 @@ namespace Grpc.Core.Internal
                 {
                     // Once we cancel, we don't have to care that much 
                     // about reads and writes.
+
+                    // TODO(jtattermusch): is this still necessary?
                     Cancel();
                 }
 
@@ -145,6 +160,11 @@ namespace Grpc.Core.Internal
             }
             // TODO(jtattermusch): handle error
 
+            if (cancelled)
+            {
+                cancellationTokenSource.Cancel();
+            }
+
             finishedServersideTcs.SetResult(null);
         }
     }