[Server] ActivateSessionAsync / CreateSessionAsync / FindServersAsync / GetEndpointsAsync / CloseSessionAsync

Libraries/Opc.Ua.Gds.Server.Common/GlobalDiscoverySampleServer.cs

@@ -171,10 +171,15 @@ protected override OperationContext ValidateRequest(
                 // check for a user name token.
                 if (securityToken is UserNameIdentityToken)
                 {
-                    lock (Lock)
+                    SemaphoreSlim.Wait();
+                    try
                     {
                         m_contexts.Add(context.RequestId, new ImpersonationContext());
                     }
+                    finally
+                    {
+                        SemaphoreSlim.Release();
+                    }
                 }
             }
 
@@ -186,7 +191,8 @@ protected override OperationContext ValidateRequest(
         /// </summary>
         protected override void OnRequestComplete(OperationContext context)
         {
-            lock (Lock)
+            SemaphoreSlim.Wait();
+            try
             {
                 if (m_contexts.TryGetValue(
                     context.RequestId,
@@ -195,6 +201,10 @@ protected override void OnRequestComplete(OperationContext context)
                     m_contexts.Remove(context.RequestId);
                 }
             }
+            finally
+            {
+                SemaphoreSlim.Release();
+            }
 
             base.OnRequestComplete(context);
         }

Libraries/Opc.Ua.Server/Server/IServerInternal.cs

@@ -29,6 +29,8 @@
 
 using System;
 using System.Collections.Generic;
+using System.Threading;
+using System.Threading.Tasks;
 
 namespace Opc.Ua.Server
 {
@@ -210,6 +212,19 @@ public interface IServerInternal : IAuditEventServer, IDisposable
         /// <param name="deleteSubscriptions">if set to <c>true</c> subscriptions are to be deleted.</param>
         void CloseSession(OperationContext context, NodeId sessionId, bool deleteSubscriptions);
 
+        /// <summary>
+        /// Closes the specified session.
+        /// </summary>
+        /// <param name="context">The context.</param>
+        /// <param name="sessionId">The session identifier.</param>
+        /// <param name="deleteSubscriptions">if set to <c>true</c> subscriptions are to be deleted.</param>
+        /// <param name="cancellationToken">The cancellation token.</param>
+        ValueTask CloseSessionAsync(
+            OperationContext context,
+            NodeId sessionId,
+            bool deleteSubscriptions,
+            CancellationToken cancellationToken = default);
+
         /// <summary>
         /// Deletes the specified subscription.
         /// </summary>

Libraries/Opc.Ua.Server/Server/ServerInternalData.cs

@@ -30,6 +30,8 @@
 using System;
 using System.Collections.Generic;
 using System.Globalization;
+using System.Threading;
+using System.Threading.Tasks;
 using Opc.Ua.Security.Certificates;
 
 namespace Opc.Ua.Server
@@ -455,7 +457,25 @@ public void CloseSession(
             NodeId sessionId,
             bool deleteSubscriptions)
         {
-            NodeManager.SessionClosingAsync(context, sessionId, deleteSubscriptions).AsTask().GetAwaiter().GetResult();
+            CloseSessionAsync(context, sessionId, deleteSubscriptions)
+                .AsTask().GetAwaiter().GetResult();
+        }
+
+        /// <summary>
+        /// Closes the specified session.
+        /// </summary>
+        /// <param name="context">The context.</param>
+        /// <param name="sessionId">The session identifier.</param>
+        /// <param name="deleteSubscriptions">if set to <c>true</c> subscriptions are to be deleted.</param>
+        /// <param name="cancellationToken">The cancellationToken</param>
+        public async ValueTask CloseSessionAsync(
+            OperationContext context,
+            NodeId sessionId,
+            bool deleteSubscriptions,
+            CancellationToken cancellationToken = default)
+        {
+            await NodeManager.SessionClosingAsync(context, sessionId, deleteSubscriptions, cancellationToken)
+                .ConfigureAwait(false);
             SubscriptionManager.SessionClosing(context, sessionId, deleteSubscriptions);
             SessionManager.CloseSession(sessionId);
         }