Register callback to notify about new channel token activation

Stack/Opc.Ua.Core/Stack/Client/UaChannelBase.cs

@@ -198,6 +198,13 @@ public IServiceMessageContext MessageContext
         /// </summary>
         public ChannelToken CurrentToken => null;
 
+        /// <inheritdoc/>
+        public event ChannelTokenActivatedEventHandler OnTokenActivated
+        {
+            add { }
+            remove { }
+        }
+
         /// <summary>
         /// Gets or sets the default timeout for requests send via the channel.
         /// </summary>
@@ -685,7 +692,7 @@ private void OnSendRequest(object state)
         #endregion
         }
         #endregion
-        
+
         /// <summary>
         /// Processes the request.
         /// </summary>

Stack/Opc.Ua.Core/Stack/Https/HttpsTransportChannel.cs

@@ -108,6 +108,13 @@ public void Dispose()
         /// <inheritdoc/>
         public ChannelToken CurrentToken => null;
 
+        /// <inheritdoc/>
+        public event ChannelTokenActivatedEventHandler OnTokenActivated
+        {
+            add { }
+            remove { }
+        }
+
         /// <inheritdoc/>
         public int OperationTimeout
         {

Stack/Opc.Ua.Core/Stack/Tcp/UaSCBinaryChannel.Symmetric.cs

@@ -36,6 +36,11 @@ public partial class UaSCUaBinaryChannel
         /// </summary>
         protected ChannelToken RenewedToken => m_renewedToken;
 
+        /// <summary>
+        /// Called when the token changes
+        /// </summary>
+        protected internal Action<ChannelToken, ChannelToken> OnTokenActivated { get; set; }
+
         /// <summary>
         /// Creates a new token.
         /// </summary>
@@ -66,6 +71,8 @@ protected void ActivateToken(ChannelToken token)
             m_currentToken = token;
             m_renewedToken = null;
 
+            OnTokenActivated?.Invoke(token, m_previousToken);
+
             Utils.LogInfo("ChannelId {0}: Token #{1} activated. CreatedAt={2:HH:mm:ss.fff}. Lifetime={3}.", Id, token.TokenId, token.CreatedAt, token.Lifetime);
         }
 
@@ -85,6 +92,8 @@ protected void DiscardTokens()
         {
             m_previousToken = null;
             m_currentToken = null;
+
+            OnTokenActivated?.Invoke(null, null);
         }
         #endregion
 

Stack/Opc.Ua.Core/Stack/Tcp/UaSCBinaryClientChannel.cs

@@ -104,6 +104,8 @@
 
             if (disposing)
             {
+                OnTokenActivated = null;
+
                 Utils.SilentDispose(m_handshakeTimer);
                 m_handshakeTimer = null;
             }
@@ -504,7 +506,7 @@
                 decoder.Close();
             }
 
- 
+
             // ready to open the channel.
             State = TcpChannelState.Opening;
 
@@ -583,7 +585,7 @@
         {
             Utils.LogTrace("ChannelId {0}: ProcessOpenSecureChannelResponse()", ChannelId);
 
-            // validate the channel state.            
+            // validate the channel state.
             if (State != TcpChannelState.Opening && State != TcpChannelState.Open)
             {
                 ForceReconnect(ServiceResult.Create(StatusCodes.BadTcpMessageTypeInvalid, "Server sent an unexpected OpenSecureChannel response."));
@@ -645,9 +647,9 @@
                 if (!(ParseResponse(chunksToProcess) is OpenSecureChannelResponse response))
                 {
                     throw ServiceResultException.Create(StatusCodes.BadTypeMismatch, "Server did not return a valid OpenSecureChannelResponse.");
                 }
 
-                // the client needs to use the creation time assigned when it sent 
+                // the client needs to use the creation time assigned when it sent
                 // the request and ignores the creation time in the response because
                 // the server and client clocks may not be synchronized.
 
@@ -685,7 +687,7 @@
                 State = TcpChannelState.Open;
                 m_reconnecting = false;
 
-                // enable reconnects. DO NOT USE! 
+                // enable reconnects. DO NOT USE!
                 // m_waitBetweenReconnects = TcpMessageLimits.MinTimeBetweenReconnects;
                 m_waitBetweenReconnects = Timeout.Infinite;
 
@@ -1164,7 +1166,7 @@
                     Socket = null;
                 }
 
-                // set the state.       
+                // set the state.
                 ChannelStateChanged(TcpChannelState.Closed, reason);
             }
         }
@@ -1281,7 +1283,7 @@
         }
 
         /// <summary>
-        /// Creates an object to manage the state of an asynchronous operation. 
+        /// Creates an object to manage the state of an asynchronous operation.
         /// </summary>
         private WriteOperation BeginOperation(int timeout, AsyncCallback callback, object state)
         {
@@ -1421,7 +1423,7 @@
         {
             ServiceResult error;
 
-            // read request buffer sizes.            
+            // read request buffer sizes.
             using (var decoder = new BinaryDecoder(messageChunk, Quotas.MessageContext))
             {
                 ReadAndVerifyMessageTypeAndSize(decoder, TcpMessageType.Error, messageChunk.Count);

Stack/Opc.Ua.Core/Stack/Tcp/UaSCBinaryTransportChannel.cs

@@ -70,6 +70,16 @@ public IMessageSocket Socket
         #endregion
 
         #region ITransportChannel Members
+
+        /// <summary>
+        /// Called when the token changes
+        /// </summary>
+        public event ChannelTokenActivatedEventHandler OnTokenActivated
+        {
+            add => m_OnTokenActivated += value;
+            remove => m_OnTokenActivated -= value;
+        }
+
         /// <summary>
         /// A masking indicating which features are implemented.
         /// </summary>
@@ -482,6 +492,9 @@ private UaSCUaBinaryClientChannel CreateChannel(ITransportWaitingConnection conn
                 channel.ReverseSocket = true;
             }
 
+            // Register the token changed event handler with the internal channel
+            channel.OnTokenActivated =
+                (current, previous) => m_OnTokenActivated?.Invoke(this, current, previous);
             return channel;
         }
         #endregion
@@ -494,6 +507,7 @@ private UaSCUaBinaryClientChannel CreateChannel(ITransportWaitingConnection conn
         private ChannelQuotas m_quotas;
         private BufferManager m_bufferManager;
         private UaSCUaBinaryClientChannel m_channel;
+        private event ChannelTokenActivatedEventHandler m_OnTokenActivated;
         private IMessageSocketFactory m_messageSocketFactory;
         #endregion
     }

Stack/Opc.Ua.Core/Stack/Transport/ITransportChannel.cs

@@ -18,7 +18,18 @@ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
 namespace Opc.Ua
 {
     /// <summary>
-    /// This is an interface to a channel which supports 
+    /// Callback when the token is activated
+    /// </summary>
+    /// <param name="channel"></param>
+    /// <param name="currentToken"></param>
+    /// <param name="previousToken"></param>
+    public delegate void ChannelTokenActivatedEventHandler(
+        ITransportChannel channel,
+        ChannelToken currentToken,
+        ChannelToken previousToken);
+
+    /// <summary>
+    /// This is an interface to a channel which supports
     /// </summary>
     public interface ITransportChannel : IDisposable
     {
@@ -47,6 +58,11 @@ public interface ITransportChannel : IDisposable
         /// </summary>
         ChannelToken CurrentToken { get; }
 
+        /// <summary>
+        /// Register for token change events
+        /// </summary>
+        event ChannelTokenActivatedEventHandler OnTokenActivated;
+
         /// <summary>
         /// Gets or sets the default timeout for requests send via the channel.
         /// </summary>
@@ -200,7 +216,7 @@ IAsyncResult BeginOpen(
 
         /// <summary>
         /// Completes an asynchronous operation to send a request over the secure channel.
-        /// Awaitable version  
+        /// Awaitable version
         /// </summary>
         /// <param name="result">The result returned from the BeginSendRequest call.</param>
         /// <param name="ct">The cancellation token.</param>