feat(opcua,host): #81 ServiceLevel SDK publisher

SdkServiceLevelPublisher writes Server.ServiceLevel through the SDK's ServerObjectState — the standard OPC UA non-transparent-redundancy signal clients use to pick a primary. Writes are guarded by DiagnosticsLock so concurrent SDK diagnostics scans don't fight with our updates. DeferredServiceLevelPublisher mirrors the DeferredAddressSpaceSink late- binding pattern: Akka actors resolve IServiceLevelPublisher at construction, hosted service swaps the SDK publisher in after StandardServer.Start. Host Program.cs registers DeferredServiceLevelPublisher as the singleton bound to IServiceLevelPublisher; OtOpcUaServerHostedService gets it injected and fills it once IServerInternal is available. Tests boot a real StandardServer on a free port (cross-platform), call Publish, then verify ServerObject.ServiceLevel.Value reflects the write. 5 new tests; OpcUaServer suite now 45/45 green (was 40, +5). Closes #81 residual. Unblocks Task 60 (OPC UA dual-endpoint + ServiceLevel tests).
2026-05-26 10:37:42 -04:00
parent 52997ee164
commit 2697af31d1
6 changed files with 238 additions and 2 deletions
@@ -0,0 +1,56 @@
+using Microsoft.Extensions.Logging;
+using Opc.Ua;
+using Opc.Ua.Server;
+using ZB.MOM.WW.OtOpcUa.Commons.OpcUa;
+
+namespace ZB.MOM.WW.OtOpcUa.OpcUaServer;
+
+/// <summary>
+/// Production <see cref="IServiceLevelPublisher"/> that writes the OPC UA Server object's
+/// <c>ServiceLevel</c> Variable through the SDK. Clients reading
+/// <c>VariableIds.Server_ServiceLevel</c> see the live value updated whenever the redundancy
+/// state changes — that's the standard OPC UA non-transparent-redundancy signal callers use
+/// to pick a primary.
+///
+/// Uses <see cref="IServerInternal.ServerObject"/> (a <see cref="ServerObjectState"/>) and
+/// its <see cref="ServerObjectState.ServiceLevel"/> child variable, which the SDK populates
+/// automatically during <see cref="DiagnosticsNodeManager"/> initialization. Writes are
+/// guarded by <see cref="IServerInternal.DiagnosticsLock"/> so concurrent diagnostics scans
+/// from the SDK don't fight with our update.
+/// </summary>
+public sealed class SdkServiceLevelPublisher : IServiceLevelPublisher
+{
+    private readonly IServerInternal _serverInternal;
+    private readonly ILogger<SdkServiceLevelPublisher> _logger;
+
+    public SdkServiceLevelPublisher(IServerInternal serverInternal, ILogger<SdkServiceLevelPublisher> logger)
+    {
+        _serverInternal = serverInternal;
+        _logger = logger;
+    }
+
+    public void Publish(byte serviceLevel)
+    {
+        var node = _serverInternal.ServerObject?.ServiceLevel;
+        if (node is null)
+        {
+            _logger.LogWarning("SdkServiceLevelPublisher: ServerObject.ServiceLevel unavailable; skipping write");
+            return;
+        }
+
+        try
+        {
+            lock (_serverInternal.DiagnosticsLock)
+            {
+                node.Value = serviceLevel;
+                node.Timestamp = DateTime.UtcNow;
+                node.StatusCode = StatusCodes.Good;
+                node.ClearChangeMasks(_serverInternal.DefaultSystemContext, includeChildren: false);
+            }
+        }
+        catch (Exception ex)
+        {
+            _logger.LogWarning(ex, "SdkServiceLevelPublisher: write to Server.ServiceLevel threw");
+        }
+    }
+}