EquipmentNamespaceContentLoader — Config-DB loader that fills the (driverInstanceId, generationId) shape the walker wire-in from PR #155 consumes. Narrow follow-up to PR #155: the ctor plumbing on OpcUaApplicationHost already takes a Func<string, EquipmentNamespaceContent?>? lookup; this PR lands the loader that will back that lookup against the central Config DB at SealedBootstrap time. DI composition in Program.cs is a separate structural PR because it needs the generation-resolve chain restructured to run before OpcUaApplicationHost construction — this one just lands the loader + unit tests so the wiring PR reduces to one factory lambda. Loader scope is one driver instance at one generation: joins Equipment filtered by (DriverInstanceId == driver, GenerationId == gen, Enabled) first, then UnsLines reachable from those Equipment rows, then UnsAreas reachable from those lines, then Tags filtered by (DriverInstanceId == driver, GenerationId == gen). Returns null when the driver has no Equipment at the supplied generation — the wire-in's null-check treats that as "skip the walker; let DiscoverAsync own the whole address space" which is the correct backward-compat behavior for non-Equipment-kind drivers (Modbus / AB CIP / TwinCAT / FOCAS whose namespace-kind is native per decisions #116-#121). Only loads the UNS branches that actually host this driver's Equipment — skips pulling unrelated UNS folders from other drivers' regions of the cluster by deriving lineIds/areaIds from the filtered Equipment set rather than reloading the full UNS tree. Enabled=false Equipment are skipped at the query level so a decommissioned machine doesn't produce a phantom browse folder — Admin still sees it in the diff view via the regular Config-DB queries but the walker's browse output reflects the operational fleet. AsNoTracking on every query because the bootstrap flow is read-only + the result is handed off to a pure-function walker immediately; change tracking would pin rows in the DbContext for the full server lifetime with no corresponding write path. Five new EquipmentNamespaceContentLoaderTests using InMemoryDatabase: (a) null result when driver has no Equipment; (b) baseline happy-path loads the full shape correctly; (c) other driver's rows at the same generation don't leak into this driver's result (per-driver scope contract); (d) same-driver rows at a different generation are skipped (per-generation scope contract per decision #148); (e) Enabled=false Equipment are skipped. Server project builds 0 errors; Server.Tests 186/186 (was 181, +5 new loader tests). Once the wiring PR lands the factory lambda in Program.cs the loader closes over the SealedBootstrap-resolved generationId + the lookup delegate delegates to LoadAsync via IServiceScopeFactory — a one-line composition, no ctor-signature churn on OpcUaApplicationHost because PR #155 already established the seam.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
2026-04-20 03:19:45 -04:00
parent f5076b4cdd
commit a29828e41e
2 changed files with 258 additions and 0 deletions
--- a/src/ZB.MOM.WW.OtOpcUa.Server/OpcUa/EquipmentNamespaceContentLoader.cs
+++ b/src/ZB.MOM.WW.OtOpcUa.Server/OpcUa/EquipmentNamespaceContentLoader.cs
@@ -0,0 +1,86 @@
+using Microsoft.EntityFrameworkCore;
+using ZB.MOM.WW.OtOpcUa.Configuration;
+using ZB.MOM.WW.OtOpcUa.Configuration.Entities;
+using ZB.MOM.WW.OtOpcUa.Core.OpcUa;
+
+namespace ZB.MOM.WW.OtOpcUa.Server.OpcUa;
+
+/// <summary>
+///     Loads the <see cref="EquipmentNamespaceContent"/> snapshot the
+///     <see cref="EquipmentNodeWalker"/> consumes, scoped to a single
+///     (driverInstanceId, generationId) pair. Joins the four row sets the walker expects:
+///     UnsAreas for the driver's cluster, UnsLines under those areas, Equipment bound to
+///     this driver + its lines, and Tags bound to this driver + its equipment — all at the
+///     supplied generation.
+/// </summary>
+/// <remarks>
+///     <para>The walker is driver-instance-scoped (decisions #116–#121 put the UNS in the
+///     Equipment-kind namespace owned by one driver instance at a time), so this loader is
+///     too — a single call returns one driver's worth of rows, never the whole fleet.</para>
+///
+///     <para>Returns <c>null</c> when the driver instance has no Equipment rows at the
+///     supplied generation. The wire-in in <see cref="OpcUaApplicationHost"/> treats null as
+///     "this driver has no UNS content, skip the walker and let DiscoverAsync own the whole
+///     address space" — the backward-compat path for drivers whose namespace kind is not
+///     Equipment (Modbus / AB CIP / TwinCAT / FOCAS).</para>
+/// </remarks>
+public sealed class EquipmentNamespaceContentLoader
+{
+    private readonly OtOpcUaConfigDbContext _db;
+
+    public EquipmentNamespaceContentLoader(OtOpcUaConfigDbContext db)
+    {
+        _db = db;
+    }
+
+    /// <summary>
+    ///     Load the walker-shaped snapshot for <paramref name="driverInstanceId"/> at
+    ///     <paramref name="generationId"/>. Returns <c>null</c> when the driver has no
+    ///     Equipment rows at that generation.
+    /// </summary>
+    public async Task<EquipmentNamespaceContent?> LoadAsync(
+        string driverInstanceId, long generationId, CancellationToken ct)
+    {
+        var equipment = await _db.Equipment
+            .AsNoTracking()
+            .Where(e => e.DriverInstanceId == driverInstanceId && e.GenerationId == generationId && e.Enabled)
+            .ToListAsync(ct).ConfigureAwait(false);
+
+        if (equipment.Count == 0)
+            return null;
+
+        // Filter UNS tree to only the lines + areas that host at least one Equipment bound to
+        // this driver — skips loading unrelated UNS branches from the cluster. LinesByArea
+        // grouping is driven off the Equipment rows so an empty line (no equipment) doesn't
+        // pull a pointless folder into the walker output.
+        var lineIds = equipment.Select(e => e.UnsLineId).Distinct(StringComparer.OrdinalIgnoreCase).ToArray();
+
+        var lines = await _db.UnsLines
+            .AsNoTracking()
+            .Where(l => l.GenerationId == generationId && lineIds.Contains(l.UnsLineId))
+            .ToListAsync(ct).ConfigureAwait(false);
+
+        var areaIds = lines.Select(l => l.UnsAreaId).Distinct(StringComparer.OrdinalIgnoreCase).ToArray();
+
+        var areas = await _db.UnsAreas
+            .AsNoTracking()
+            .Where(a => a.GenerationId == generationId && areaIds.Contains(a.UnsAreaId))
+            .ToListAsync(ct).ConfigureAwait(false);
+
+        // Tags belonging to this driver at this generation. Walker skips Tags with null
+        // EquipmentId (those are SystemPlatform-kind Galaxy tags per decision #120) but we
+        // load them anyway so the same rowset can drive future non-Equipment-kind walks
+        // without re-hitting the DB. Filtering here is a future optimization; today the
+        // per-tag cost is bounded by driver scope.
+        var tags = await _db.Tags
+            .AsNoTracking()
+            .Where(t => t.DriverInstanceId == driverInstanceId && t.GenerationId == generationId)
+            .ToListAsync(ct).ConfigureAwait(false);
+
+        return new EquipmentNamespaceContent(
+            Areas: areas,
+            Lines: lines,
+            Equipment: equipment,
+            Tags: tags);
+    }
+}