refactor: remove ClusterClient streaming path (DebugStreamEvent), events flow via gRPC

src/ScadaLink.Commons/Messages/DebugView/DebugStreamEvent.cs

@@ -1,8 +0,0 @@
-namespace ScadaLink.Commons.Messages.DebugView;
-
-/// <summary>
-/// Wraps a debug stream event (AttributeValueChanged or AlarmStateChanged) with
-/// the correlationId for routing back to the correct DebugStreamBridgeActor on central.
-/// Sent from InstanceActor → SiteCommunicationActor → ClusterClient → CentralCommunicationActor.
-/// </summary>
-public record DebugStreamEvent(string CorrelationId, object Event);

src/ScadaLink.Communication/Actors/CentralCommunicationActor.cs

@@ -86,8 +86,6 @@ public class CentralCommunicationActor : ReceiveActor
         // Route enveloped messages to sites
         Receive<SiteEnvelope>(HandleSiteEnvelope);
 
-        // Route debug stream events from sites to the correct bridge actor
-        Receive<Commons.Messages.DebugView.DebugStreamEvent>(HandleDebugStreamEvent);
     }
 
     private void HandleHeartbeat(HeartbeatMessage heartbeat)
@@ -96,18 +94,6 @@ public class CentralCommunicationActor : ReceiveActor
         Context.Parent.Tell(heartbeat);
     }
 
-    private void HandleDebugStreamEvent(Commons.Messages.DebugView.DebugStreamEvent msg)
-    {
-        if (_debugSubscriptions.TryGetValue(msg.CorrelationId, out var entry))
-        {
-            entry.Subscriber.Tell(msg.Event);
-        }
-        else
-        {
-            _log.Debug("No debug subscription found for correlationId {0}, dropping event", msg.CorrelationId);
-        }
-    }
-
     private void HandleSiteHealthReport(SiteHealthReport report)
     {
         var aggregator = _serviceProvider.GetService<ICentralHealthAggregator>();

src/ScadaLink.Communication/Actors/SiteCommunicationActor.cs

@@ -146,12 +146,6 @@ public class SiteCommunicationActor : ReceiveActor, IWithTimers
                 new ClusterClient.Send("/user/central-communication", msg), Self);
         });
 
-        // Internal: forward debug stream events to central (site→central streaming)
-        Receive<DebugStreamEvent>(msg =>
-        {
-            _centralClient?.Tell(
-                new ClusterClient.Send("/user/central-communication", msg), Self);
-        });
     }
 
     protected override void PreStart()

src/ScadaLink.SiteRuntime/Actors/InstanceActor.cs

@@ -50,10 +50,6 @@ public class InstanceActor : ReceiveActor
     private readonly Dictionary<string, IActorRef> _alarmActors = new();
     private FlattenedConfiguration? _configuration;
 
-    // WP-25: Debug view subscribers
-    private readonly HashSet<string> _debugSubscriberCorrelationIds = new();
-    private ActorSelection? _siteCommActor;
-
     // DCL manager actor reference for subscribing to tag values
     private readonly IActorRef? _dclManager;
     // Maps tag paths back to attribute canonical names for DCL updates
@@ -150,9 +146,6 @@ public class InstanceActor : ReceiveActor
         base.PreStart();
         _logger.LogInformation("InstanceActor started for {Instance}", _instanceUniqueName);
 
-        // Resolve SiteCommunicationActor for routing debug stream events back to central
-        _siteCommActor = Context.ActorSelection("/user/site-communication");
-
         // Asynchronously load static overrides from SQLite and pipe to self
         var self = Self;
         _storage.GetStaticOverridesAsync(_instanceUniqueName).ContinueWith(t =>
@@ -370,12 +363,6 @@ public class InstanceActor : ReceiveActor
 
         // WP-23: Publish to site-wide stream
         _streamManager?.PublishAlarmStateChanged(changed);
-
-        // Forward to debug subscribers via SiteCommunicationActor → ClusterClient → central
-        foreach (var correlationId in _debugSubscriberCorrelationIds)
-        {
-            _siteCommActor?.Tell(new DebugStreamEvent(correlationId, changed));
-        }
     }
 
     /// <summary>
@@ -383,9 +370,6 @@ public class InstanceActor : ReceiveActor
     /// </summary>
     private void HandleSubscribeDebugView(SubscribeDebugViewRequest request)
     {
-        var subscriptionId = request.CorrelationId;
-        _debugSubscriberCorrelationIds.Add(subscriptionId);
-
         // Build snapshot from current state
         var now = DateTimeOffset.UtcNow;
         var attributeValues = _attributes.Select(kvp => new AttributeValueChanged(
@@ -412,8 +396,8 @@ public class InstanceActor : ReceiveActor
         Sender.Tell(snapshot);
 
         _logger.LogDebug(
-            "Debug view subscriber added for {Instance}, subscriptionId={Id}",
+            "Debug view snapshot sent for {Instance}, correlationId={Id}",
-            _instanceUniqueName, subscriptionId);
+            _instanceUniqueName, request.CorrelationId);
     }
 
     /// <summary>
@@ -421,10 +405,8 @@ public class InstanceActor : ReceiveActor
     /// </summary>
     private void HandleUnsubscribeDebugView(UnsubscribeDebugViewRequest request)
     {
-        _debugSubscriberCorrelationIds.Remove(request.CorrelationId);
-
         _logger.LogDebug(
-            "Debug view subscriber removed for {Instance}, correlationId={Id}",
+            "Debug view unsubscribe for {Instance}, correlationId={Id}",
             _instanceUniqueName, request.CorrelationId);
     }
 
@@ -478,12 +460,6 @@ public class InstanceActor : ReceiveActor
         {
             alarmActor.Tell(changed);
         }
-
-        // Forward to debug subscribers via SiteCommunicationActor → ClusterClient → central
-        foreach (var correlationId in _debugSubscriberCorrelationIds)
-        {
-            _siteCommActor?.Tell(new DebugStreamEvent(correlationId, changed));
-        }
     }
 
     /// <summary>

tests/ScadaLink.Commons.Tests/ArchitecturalConstraintTests.cs

@@ -136,6 +136,15 @@ public class ArchitecturalConstraintTests
         }
     }
 
+    [Fact]
+    public void DebugStreamEvent_ShouldNotExist()
+    {
+        // DebugStreamEvent was removed when debug streaming moved from ClusterClient to gRPC.
+        // Events now flow via SiteStreamManager → StreamRelayActor → gRPC channel.
+        var type = CommonsAssembly.GetTypes().FirstOrDefault(t => t.Name == "DebugStreamEvent");
+        Assert.Null(type);
+    }
+
     [Fact]
     public void AllEnums_ShouldBeSingularNamed()
     {

tests/ScadaLink.SiteRuntime.Tests/Actors/InstanceActorIntegrationTests.cs

@@ -41,21 +41,6 @@ public class InstanceActorIntegrationTests : TestKit, IDisposable
             ScriptExecutionTimeoutSeconds = 30
         };
 
-        // Create a fake site-communication actor that unwraps DebugStreamEvent
-        // and forwards the inner event to TestActor (simulating the ClusterClient relay)
-        Sys.ActorOf(Props.Create(() => new DebugStreamEventForwarder(TestActor)), "site-communication");
-    }
-
-    /// <summary>
-    /// Test helper: stands in for SiteCommunicationActor, unwraps DebugStreamEvent
-    /// and forwards the inner event to a target actor.
-    /// </summary>
-    private class DebugStreamEventForwarder : ReceiveActor
-    {
-        public DebugStreamEventForwarder(IActorRef target)
-        {
-            Receive<DebugStreamEvent>(msg => target.Tell(msg.Event));
-        }
     }
 
     void IDisposable.Dispose()
@@ -169,22 +154,23 @@ public class InstanceActorIntegrationTests : TestKit, IDisposable
     }
 
     [Fact]
-    public void InstanceActor_WP25_DebugViewSubscriber_ReceivesChanges()
+    public void InstanceActor_WP25_DebugViewSubscribe_NoLongerForwardsEventsViaClusterClient()
     {
+        // Events now flow via gRPC (SiteStreamManager → StreamRelayActor → gRPC),
+        // not via ClusterClient. Subscribing returns a snapshot but ongoing events
+        // are NOT forwarded to the subscriber actor.
         var actor = CreateInstanceWithScripts("Pump1");
 
-        // Subscribe to debug view
+        // Subscribe to debug view — should still get snapshot
         actor.Tell(new SubscribeDebugViewRequest("Pump1", "debug-2"));
         ExpectMsg<DebugViewSnapshot>(TimeSpan.FromSeconds(5));
 
-        // Now change an attribute
+        // Change an attribute
         actor.Tell(new AttributeValueChanged(
             "Pump1", "Temperature", "Temperature", "200", "Good", DateTimeOffset.UtcNow));
 
-        // The subscriber should receive the change notification
+        // Should NOT receive change notification (old ClusterClient path removed)
-        var changed = ExpectMsg<AttributeValueChanged>(TimeSpan.FromSeconds(5));
+        ExpectNoMsg(TimeSpan.FromSeconds(1));
-        Assert.Equal("Temperature", changed.AttributeName);
-        Assert.Equal("200", changed.Value?.ToString());
     }
 
     [Fact]
@@ -223,20 +209,14 @@ public class InstanceActorIntegrationTests : TestKit, IDisposable
 
         var actor = CreateInstanceWithScripts("Pump1", alarms: alarms);
 
-        // Subscribe to debug view to observe alarm state changes
+        // Wait for initialization
-        actor.Tell(new SubscribeDebugViewRequest("Pump1", "debug-alarm"));
+        Thread.Sleep(500);
-        ExpectMsg<DebugViewSnapshot>(TimeSpan.FromSeconds(5));
 
-        // Send value outside range to trigger alarm
+        // Verify alarm actor was created by checking the debug snapshot includes the alarm
-        actor.Tell(new AttributeValueChanged(
+        actor.Tell(new DebugSnapshotRequest("Pump1", "snap-alarm"));
-            "Pump1", "Temperature", "Temperature", "150", "Good", DateTimeOffset.UtcNow));
+        var snapshot = ExpectMsg<DebugViewSnapshot>(TimeSpan.FromSeconds(5));
 
-        // Should receive the attribute change first (from debug subscription)
+        Assert.Single(snapshot.AlarmStates);
-        ExpectMsg<AttributeValueChanged>(TimeSpan.FromSeconds(5));
+        Assert.Equal("HighTemp", snapshot.AlarmStates[0].AlarmName);
-
-        // Then the alarm state change (forwarded by Instance Actor)
-        var alarmMsg = ExpectMsg<AlarmStateChanged>(TimeSpan.FromSeconds(5));
-        Assert.Equal("HighTemp", alarmMsg.AlarmName);
-        Assert.Equal(Commons.Types.Enums.AlarmState.Active, alarmMsg.State);
     }
 }