fix(opcuaclient): #649 review minors - CodeBits match, Bad-only exception ctor, BadNoData + Raw-resume tests, latent-impact docs

Claude-Session: https://claude.ai/code/session_01Ef2ozxS7QPanGT8uoATbTe
2026-10-08 19:29:47 -04:00
parent 22e79112b6
commit b8c2136732
6 changed files with 122 additions and 8 deletions
@@ -17,6 +17,7 @@ public sealed class OpcUaClientDriverHistoryWireTests
    private const string HistRef = "Sim/dev1/Hist";
    private const string HistTag = "Plant.Hist.Series";
    private const uint Uncertain = 0x40000000u;
+    private const uint BadNoData = 0x809B0000u;
    private const uint BadUserAccessDenied = 0x801F0000u;
    private const uint BadHistoryOperationUnsupported = 0x80720000u;

@@ -55,6 +56,9 @@ public sealed class OpcUaClientDriverHistoryWireTests
            // Minimum stands in for "the backend refuses with some OTHER Bad status" (#649).
            if (aggregate == HistoryAggregateType.Minimum)
                throw new HistoryReadStatusException(BadUserAccessDenied);
+            // Maximum stands in for a node-level BadNoData ("nothing in the window"), which must stay empty.
+            if (aggregate == HistoryAggregateType.Maximum)
+                throw new HistoryReadStatusException(BadNoData);
            if (aggregate != HistoryAggregateType.Average)
                throw new HistoryAggregateNotSupportedException(aggregate);

@@ -204,6 +208,21 @@ public sealed class OpcUaClientDriverHistoryWireTests
        lock (fake.Calls) fake.Calls.ShouldContain($"processed:{HistTag}:Minimum");
    }

+    [Fact]
+    public async Task A_node_level_BadNoData_stays_an_empty_result_not_an_error()
+    {
+        var ct = TestContext.Current.CancellationToken;
+        var (rig, fake, drv) = await StartAsync("hist-badnodata", ct);
+        await using var _r = rig;
+        await using var _d = drv;
+
+        var result = await drv.ReadProcessedAsync(
+            HistRef, At(0), At(6), TimeSpan.FromSeconds(2), HistoryAggregateType.Maximum, ct);
+
+        result.Samples.ShouldBeEmpty();
+        lock (fake.Calls) fake.Calls.ShouldContain($"processed:{HistTag}:Maximum", "the call must have reached the backend");
+    }
+
    [Fact]
    public async Task A_Good_read_with_no_samples_in_the_window_is_still_empty_data_not_an_error()
    {
@@ -312,6 +312,61 @@ public sealed class NodeManagerHistoryReadPagingTests : IDisposable
        await host.DisposeAsync();
    }

+    /// <summary>A passthrough backend's Bad status on a RESUME read surfaces verbatim for that node only (#649):
+    /// no outbound continuation point, the cursor is consumed (no stray cursor), and a sibling node in the same
+    /// batch is unaffected.</summary>
+    [Fact]
+    public async Task Raw_resume_read_that_throws_HistoryReadStatusException_surfaces_the_code_and_isolates_the_sibling()
+    {
+        var (host, server) = await BootAsync();
+        var nm = server.NodeManager!;
+        nm.HistoryContinuationStore = new InMemoryHistoryContinuationStore();
+        var fake = new SeriesHistorianDataSource(MakeSeries(count: 250, stepSeconds: 1));
+        nm.HistorianDataSource = fake;
+
+        nm.EnsureVariable("eq-1/bad", parentFolderNodeId: null, displayName: "Bad", dataType: "Double",
+            writable: false, historianTagname: "WW.Bad", realm: AddressSpaceRealm.Uns);
+        nm.EnsureVariable("eq-1/ok", parentFolderNodeId: null, displayName: "Ok", dataType: "Double",
+            writable: false, historianTagname: "WW.Ok", realm: AddressSpaceRealm.Uns);
+        var badId = nm.TryGetVariable("eq-1/bad")!.NodeId;
+        var okId = nm.TryGetVariable("eq-1/ok")!.NodeId;
+
+        // Page 1 succeeds and emits a continuation point.
+        var (_, _, cp1) = ReadRaw(nm, badId, Epoch, Epoch.AddHours(1), max: 100, inboundCp: null);
+        cp1.ShouldNotBeNull();
+
+        // The backend now refuses the bad node; one batch resumes it and freshly reads the sibling.
+        fake.FailTagname = "WW.Bad";
+        var context = new OperationContext(
+            new RequestHeader(), secureChannelContext: null, RequestType.HistoryRead, identity: null);
+        var details = new ReadRawModifiedDetails
+        {
+            StartTime = Epoch, EndTime = Epoch.AddHours(1), NumValuesPerNode = 100, IsReadModified = false,
+        };
+        var nodesToRead = new List<HistoryReadValueId>
+        {
+            new() { NodeId = badId, ContinuationPoint = cp1 },
+            new() { NodeId = okId },
+        };
+        var results = new List<SdkHistoryReadResult> { null!, null! };
+        var errors = new List<ServiceResult> { null!, null! };
+        nm.HistoryRead(context, details, TimestampsToReturn.Both,
+            releaseContinuationPoints: false, nodesToRead, results, errors);
+
+        errors[0].StatusCode.Code.ShouldBe(StatusCodes.BadUserAccessDenied);
+        results[0].ContinuationPoint.ShouldBeNull();
+        errors[1].StatusCode.Code.ShouldBe(StatusCodes.Good);
+        ((HistoryData)ExtensionObject.ToEncodeable(results[1].HistoryData)).DataValues.Count.ShouldBe(100);
+        results[1].ContinuationPoint.ShouldNotBeNull("the sibling is full-page and pages normally");
+
+        // The consumed cursor is gone: nothing stray to resume.
+        fake.FailTagname = null;
+        var (_, e, _) = ReadRaw(nm, badId, Epoch, Epoch.AddHours(1), max: 100, inboundCp: cp1);
+        e.StatusCode.Code.ShouldBe(StatusCodes.BadContinuationPointInvalid);
+
+        await host.DisposeAsync();
+    }
+
    // --- helpers --------------------------------------------------------------------------------

    /// <summary>Issue a single-node Raw HistoryRead and return that node's decoded sample values, error,
@@ -412,6 +467,9 @@ public sealed class NodeManagerHistoryReadPagingTests : IDisposable
    {
        private int _readCount;
        public int ReadCount => _readCount;
+
+        /// <summary>When set, a Raw read of this tagname throws <see cref="HistoryReadStatusException"/> (#649).</summary>
+        public volatile string? FailTagname;
        public void ResetReadCount() => _readCount = 0;

        public Task<HistorianRead> ReadRawAsync(
@@ -419,6 +477,8 @@ public sealed class NodeManagerHistoryReadPagingTests : IDisposable
            CancellationToken cancellationToken)
        {
            Interlocked.Increment(ref _readCount);
+            if (FailTagname is { } bad && bad == fullReference)
+                throw new HistoryReadStatusException(StatusCodes.BadUserAccessDenied);
            var window = series
                .Where(s => (s.SourceTimestampUtc ?? DateTime.MinValue) >= startUtc
                            && (s.SourceTimestampUtc ?? DateTime.MinValue) <= endUtc)