feat(runtime): HistorianAdapter + PeerOpcUaProbe + DbHealthProbe actors (engine wiring tracked as F11/F12)

2026-05-26 05:09:06 -04:00
parent e115f13104
commit 28639cb14d
4 changed files with 194 additions and 0 deletions
@@ -0,0 +1,58 @@
+using Akka.Actor;
+using Akka.Event;
+using Microsoft.EntityFrameworkCore;
+using ZB.MOM.WW.OtOpcUa.Configuration;
+
+namespace ZB.MOM.WW.OtOpcUa.Runtime.Health;
+
+/// <summary>
+/// Single-flight cached health probe against the ConfigDb. Reads cached state via
+/// <c>Ask&lt;DbHealthStatus&gt;</c>; a single SELECT 1 runs at most every <c>RefreshInterval</c>.
+/// Consumed by both the host's <c>/health/ready</c> endpoint (Task 54) and
+/// <c>RedundancyStateActor</c>'s stale calc.
+/// </summary>
+public sealed class DbHealthProbeActor : ReceiveActor, IWithTimers
+{
+    public static readonly TimeSpan RefreshInterval = TimeSpan.FromSeconds(5);
+
+    public sealed class GetStatus { public static readonly GetStatus Instance = new(); private GetStatus() { } }
+    public sealed record DbHealthStatus(bool Reachable, DateTime AsOfUtc, string? LastError);
+    public sealed class Tick { public static readonly Tick Instance = new(); private Tick() { } }
+
+    private readonly IDbContextFactory<OtOpcUaConfigDbContext> _dbFactory;
+    private readonly ILoggingAdapter _log = Context.GetLogger();
+    private DbHealthStatus _last = new(false, DateTime.MinValue, "not probed yet");
+
+    public ITimerScheduler Timers { get; set; } = null!;
+
+    public static Props Props(IDbContextFactory<OtOpcUaConfigDbContext> dbFactory) =>
+        Akka.Actor.Props.Create(() => new DbHealthProbeActor(dbFactory));
+
+    public DbHealthProbeActor(IDbContextFactory<OtOpcUaConfigDbContext> dbFactory)
+    {
+        _dbFactory = dbFactory;
+        Receive<GetStatus>(_ => Sender.Tell(_last));
+        Receive<Tick>(_ => RunProbe());
+    }
+
+    protected override void PreStart()
+    {
+        RunProbe();
+        Timers.StartPeriodicTimer("probe", Tick.Instance, RefreshInterval);
+    }
+
+    private void RunProbe()
+    {
+        try
+        {
+            using var db = _dbFactory.CreateDbContext();
+            _ = db.Deployments.AsNoTracking().Take(1).ToList();
+            _last = new DbHealthStatus(true, DateTime.UtcNow, null);
+        }
+        catch (Exception ex)
+        {
+            _last = new DbHealthStatus(false, DateTime.UtcNow, ex.Message);
+            _log.Warning(ex, "DbHealthProbe: probe failed");
+        }
+    }
+}