Files
UA-.NETStandard/tests/Opc.Ua.Subscriptions.Tests/MonitorValueChangeTests.cs
romanett 9b034f8291 Enable nullable reference types centrally; migrate all unset and annotations-only projects (#4700)
# Description

Nullable reference types are now enabled once, in `common.props`, and
every project in the repository builds warning-clean with them.

**Configuration**
- `<Nullable>enable</Nullable>` lives in `common.props`. All per-project
`<Nullable>` settings are removed: 178 project files (enable,
annotations, and the `disable` in the three Aot test projects).
- 419 per-file `#nullable enable`/`restore` directives and the 4
`#nullable disable` directives are removed.
- Kept on purpose:
- The 5 `<auto-generated>` schema files (`UANodeSet.cs`, `UA Type
Dictionary.cs`, `OPCBinarySchema.cs`, `SecuredApplication.cs`,
`PInvokeHelper.cs`) keep `#nullable enable`. The compiler ignores the
project setting in generated code, so the directive is required there.
- `tests/Opc.Ua.Interop.LegacyPeer` keeps `disable`. It builds against
the 1.5.378 packages and does not import the repository props.
- `docs/DeveloperGuide.md` and `.github/copilot-instructions.md` now
describe the central setting.

**Migration** (the 43 unset and 13 annotations-only projects, roughly
10k diagnostics)
- **Production code: annotated at the declarations.** Covers
`tools/Opc.Ua.SourceGeneration.Core`, `src/Opc.Ua.Lds.Server` and the
LDS sample.
- Members, parameters and returns are nullable where null actually
flows.
- Null-check helpers carry `[NotNullWhen]` (`IsNull`, `IsValidXmlName`,
`IsMethodTypeDesign`).
- `CoreUtils.Format`, `Utils.Format`, `ITemplateWriter.WriteLine` take
`params object?[]`. `Template.AddReplacement` takes `string?` (rendering
already skips null replacements).
- `IRegisteredServerStore.RegisterAsync` returns
`Task<RegistrationEntry?>`: it returns null when a registration is
removed.
- Dereferences backed by an invariant (for example, the validated model)
use `!`, so runtime behaviour is unchanged.
- **Behavioural changes in production code** (small, deliberate):
- `NodeSetToModelDesign` throws `InvalidOperationException` when the
file is not a NodeSet. Before, it threw a NullReferenceException on the
next line.
- `ModelDesignValidator` starts its lookup tables empty instead of null.
A redundant `if (m_nodes == null) return;` guard is gone.
- **Test code: minimal annotations.**
  - `?` on values that can be null, `!` where the test asserts non-null.
  - `= null!` for fixture members assigned in SetUp.
- `TryGetStructure<T>(out T? x)` where the inferred `T?` broke the
`IEncodeable` constraint.
- A few redundant `== null` checks on structs (`NodeId`, `ArrayOf<T>`)
folded into the adjacent `IsNull`/`Count` checks.

**Notes for reviewers**
- The diff is large (~1,500 files) but almost entirely mechanical: `?`,
`!` and directive removal. The non-annotation changes are listed above.
- Known follow-up, not done here:
`IModelDesign.Namespaces/TargetNamespace/NamespaceUris` stay
non-nullable even though the validator returns null before it loads a
dictionary. Making them nullable would ripple through every generator
call site.

## Related Issues

- Fixes #4439

## Checklist

- [ ] I have signed the
[CLA](https://opcfoundation.org/license/cla/ContributorLicenseAgreementv1.0.pdf)
and read the
[CONTRIBUTING](https://github.com/OPCFoundation/UA-.NETStandard/blob/master/CONTRIBUTING.md)
doc.
- [ ] I have added tests that prove my fix is effective or that my
feature works and increased code coverage.
- [x] I have added all necessary documentation.
- [x] I have verified that my changes do not introduce (new) build or
analyzer warnings.
- [ ] I ran **all** tests locally using the **UA.slnx** solution against
at least .net **framework** and .net **10**, and all passed.
- [ ] I fixed **all** failing and flaky tests in the CI pipelines and
**all** CodeQL warnings.
- [ ] I have addressed **all** PR feedback received.

The "no new warnings" box covers net10.0 and net48: full non-incremental
builds of `UA.slnx`, `tools/SourceGeneration.slnx`,
`tools/MigrationAnalyzer.slnx` and the Aot test projects finished with 0
warnings and 0 errors under the repository's warnings-as-errors
settings. net9.0 and net8.0 also had no nullable diagnostics, but they
were not rebuilt after the final fixes. Tests have not been run locally
yet.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

---------

Co-authored-by: Claude Opus 5.5 <noreply@anthropic.com>
2026-10-08 08:48:13 +02:00

1273 lines
46 KiB
C#

/* ========================================================================
* Copyright (c) 2005-2025 The OPC Foundation, Inc. All rights reserved.
*
* OPC Foundation MIT License 1.00
*
* Permission is hereby granted, free of charge, to any person
* obtaining a copy of this software and associated documentation
* files (the "Software"), to deal in the Software without
* restriction, including without limitation the rights to use,
* copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the
* Software is furnished to do so, subject to the following
* conditions:
*
* The above copyright notice and this permission notice shall be
* included in all copies or substantial portions of the Software.
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
* OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
* HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
* WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
* FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
* OTHER DEALINGS IN THE SOFTWARE.
*
* The complete license agreement can be found here:
* http://opcfoundation.org/License/MIT/1.00/
* ======================================================================*/
using System;
using System.Collections.Generic;
using System.Linq;
using System.Threading;
using System.Threading.Tasks;
using NUnit.Framework;
using Opc.Ua.Client.TestFramework;
namespace Opc.Ua.Subscriptions.Tests
{
/// <summary>
/// compliance tests for Monitor Value Change V2 covering
/// data change on each built-in type, filter triggers, value
/// change timing, identical value writes, queue overflow with
/// rapid changes, and multiple monitored items.
/// </summary>
[NonParallelizable]
[TestFixture]
[Category("Conformance")]
[Category("MonitoredItem")]
[Category("MonitorValueChange")]
public class MonitorValueChangeTests : TestFixture
{
[SetUp]
public async Task SetUp()
{
m_subscriptionId = await CreateSetupSubscriptionAsync(
publishingInterval: 100, requestedLifetimeCount: 100,
requestedMaxKeepAliveCount: 10).ConfigureAwait(false);
}
[TearDown]
public async Task TearDown()
{
if (m_subscriptionId > 0)
{
try
{
await Session.DeleteSubscriptionsAsync(
null,
new uint[] { m_subscriptionId }.ToArrayOf(),
CancellationToken.None).ConfigureAwait(false);
}
catch (ServiceResultException)
{
// Subscription may already be deleted
}
m_subscriptionId = 0;
}
}
[TestCase(0)]
[TestCase(1)]
[TestCase(2)]
[TestCase(3)]
[TestCase(4)]
[TestCase(5)]
[TestCase(6)]
[TestCase(7)]
[TestCase(8)]
[TestCase(9)]
[TestCase(10)]
[TestCase(11)]
[TestCase(12)]
[TestCase(13)]
[TestCase(14)]
[TestCase(15)]
[TestCase(16)]
[TestCase(17)]
[TestCase(18)]
[Category("LongRunning")]
public async Task DataChangeOnScalarTypeAsync(int index)
{
ExpandedNodeId expandedId =
Constants.ScalarStaticNodes[index];
NodeId nodeId = ToNodeId(expandedId);
try
{
CreateMonitoredItemsResponse createResp =
await CreateSingleItemAsync(
CreateItemRequest(nodeId, 1, samplingInterval: 50))
.ConfigureAwait(false);
Assert.That(
StatusCode.IsGood(createResp.Results[0].StatusCode),
Is.True,
$"Failed to create item for index {index}");
// Drain the initial data-change notification
await DrainPublishAsync().ConfigureAwait(false);
Variant testValue = GetTestValueForIndex(index);
bool writeOk =
await TryWriteVariantAsync(nodeId, testValue)
.ConfigureAwait(false);
if (!writeOk)
{
// Some types (e.g. NodeId) may be read-only;
// just verify monitor creation succeeded.
return;
}
// Retry publish to handle timing variations
DataChangeNotification? dcn = null;
for (int attempt = 0; attempt < 3 && dcn == null; attempt++)
{
dcn = await PublishAndGetDcnAsync(
500 + (attempt * 300)).ConfigureAwait(false);
}
if (dcn == null)
{
Assert.Ignore(
$"No DCN received for index {index} after retries.");
}
Assert.That(dcn.MonitoredItems.Count, Is.GreaterThan(0),
$"DCN has no items for index {index}");
}
catch (ServiceResultException sre) when (IsTransientCiTimeoutStatus(sre.StatusCode))
{
Assert.Ignore(
$"Timing-sensitive: scalar data-change roundtrip interrupted by CI runner load ({sre.StatusCode}).");
}
}
[Test]
public async Task DataChangeFilterStatusOnlyNoNotifyOnValueChangeAsync()
{
NodeId nodeId = ToNodeId(Constants.ScalarStaticInt32);
var filter = new DataChangeFilter
{
Trigger = DataChangeTrigger.Status,
DeadbandType = (uint)DeadbandType.None,
DeadbandValue = 0
};
CreateMonitoredItemsResponse createResp =
await CreateSingleItemAsync(
CreateItemRequest(nodeId, 10,
samplingInterval: 50,
filter: new ExtensionObject(filter)))
.ConfigureAwait(false);
StatusCode status = createResp.Results[0].StatusCode;
if (status == StatusCodes.BadFilterNotAllowed ||
status == StatusCodes.BadMonitoredItemFilterUnsupported)
{
Assert.Fail("Server does not support StatusOnly.");
}
Assert.That(StatusCode.IsGood(status), Is.True);
await DrainPublishAsync().ConfigureAwait(false);
// Write a new value — status does not change
await WriteVariantAsync(nodeId, new Variant(99999))
.ConfigureAwait(false);
DataChangeNotification dcn =
await PublishAndGetDcnAsync(500).ConfigureAwait(false);
// StatusOnly: value-only change should not trigger DCN
bool noValueNotification = dcn == null ||
dcn.MonitoredItems.Count == 0;
Assert.That(noValueNotification, Is.True,
"StatusOnly trigger should not notify on value change");
}
[Test]
public async Task DataChangeFilterStatusValueNotifyOnValueChangeAsync()
{
NodeId nodeId = ToNodeId(Constants.ScalarStaticInt32);
var filter = new DataChangeFilter
{
Trigger = DataChangeTrigger.StatusValue,
DeadbandType = (uint)DeadbandType.None,
DeadbandValue = 0
};
CreateMonitoredItemsResponse createResp =
await CreateSingleItemAsync(
CreateItemRequest(nodeId, 11,
samplingInterval: 50,
filter: new ExtensionObject(filter)))
.ConfigureAwait(false);
StatusCode status = createResp.Results[0].StatusCode;
if (status == StatusCodes.BadFilterNotAllowed)
{
Assert.Fail("Server does not support filter.");
}
Assert.That(StatusCode.IsGood(status), Is.True);
await DrainPublishAsync().ConfigureAwait(false);
await WriteVariantAsync(nodeId, new Variant(77777))
.ConfigureAwait(false);
DataChangeNotification dcn =
await PublishAndGetDcnAsync().ConfigureAwait(false);
Assert.That(dcn, Is.Not.Null);
Assert.That(dcn.MonitoredItems.Count, Is.GreaterThan(0),
"StatusValue trigger should notify on value change");
}
[Test]
public async Task
DataChangeFilterStatusValueTimestampNotifyAlways()
{
NodeId nodeId =
VariableIds.Server_ServerStatus_CurrentTime;
var filter = new DataChangeFilter
{
Trigger = DataChangeTrigger.StatusValueTimestamp,
DeadbandType = (uint)DeadbandType.None,
DeadbandValue = 0
};
CreateMonitoredItemsResponse createResp =
await CreateSingleItemAsync(
CreateItemRequest(nodeId, 12,
samplingInterval: 50,
filter: new ExtensionObject(filter)))
.ConfigureAwait(false);
StatusCode status = createResp.Results[0].StatusCode;
if (status == StatusCodes.BadFilterNotAllowed)
{
Assert.Fail("Server does not support filter.");
}
Assert.That(StatusCode.IsGood(status), Is.True);
// Dynamic node — timestamp always changes
DataChangeNotification dcn =
await PublishAndGetDcnAsync(500).ConfigureAwait(false);
Assert.That(dcn, Is.Not.Null);
Assert.That(dcn.MonitoredItems.Count, Is.GreaterThan(0),
"SVT trigger on dynamic node should always notify");
}
[Test]
public async Task DataChangeFilterDefaultTriggerIsStatusValueAsync()
{
NodeId nodeId = ToNodeId(Constants.ScalarStaticInt32);
// No explicit filter → default trigger is StatusValue
CreateMonitoredItemsResponse createResp =
await CreateSingleItemAsync(
CreateItemRequest(nodeId, 13, samplingInterval: 50))
.ConfigureAwait(false);
Assert.That(
StatusCode.IsGood(createResp.Results[0].StatusCode),
Is.True);
await DrainPublishAsync().ConfigureAwait(false);
await WriteVariantAsync(nodeId, new Variant(88888))
.ConfigureAwait(false);
DataChangeNotification dcn =
await PublishAndGetDcnAsync().ConfigureAwait(false);
Assert.That(dcn, Is.Not.Null);
Assert.That(dcn.MonitoredItems.Count, Is.GreaterThan(0),
"Default trigger should notify on value change");
}
[Test]
public async Task
DataChangeFilterInvalidTriggerValueReturnsError()
{
NodeId nodeId = ToNodeId(Constants.ScalarStaticInt32);
var filter = new DataChangeFilter
{
Trigger = (DataChangeTrigger)999,
DeadbandType = (uint)DeadbandType.None,
DeadbandValue = 0
};
CreateMonitoredItemsResponse createResp =
await CreateSingleItemAsync(
CreateItemRequest(nodeId, 14,
filter: new ExtensionObject(filter)))
.ConfigureAwait(false);
StatusCode status = createResp.Results[0].StatusCode;
Assert.That(StatusCode.IsBad(status), Is.True,
"Invalid trigger should return a Bad status");
}
[Test]
public async Task
DataChangeFilterOnNonVariableNodeReturnsError()
{
// Objects folder is an Object, not a Variable
NodeId objectNode = ObjectIds.ObjectsFolder;
var filter = new DataChangeFilter
{
Trigger = DataChangeTrigger.StatusValue,
DeadbandType = (uint)DeadbandType.None,
DeadbandValue = 0
};
CreateMonitoredItemsResponse createResp =
await CreateSingleItemAsync(
CreateItemRequest(objectNode, 15,
filter: new ExtensionObject(filter)))
.ConfigureAwait(false);
StatusCode status = createResp.Results[0].StatusCode;
// Expecting Bad — filter on non-variable attribute
Assert.That(StatusCode.IsBad(status), Is.True,
"DataChange filter on Object node should fail");
}
[Test]
public async Task
ValueChangeNotificationWithinSamplingInterval()
{
NodeId nodeId = ToNodeId(Constants.ScalarStaticInt32);
CreateMonitoredItemsResponse createResp =
await CreateSingleItemAsync(
CreateItemRequest(nodeId, 20, samplingInterval: 200))
.ConfigureAwait(false);
Assert.That(
StatusCode.IsGood(createResp.Results[0].StatusCode),
Is.True);
await DrainPublishAsync().ConfigureAwait(false);
await WriteVariantAsync(nodeId, new Variant(11111))
.ConfigureAwait(false);
// Wait longer than sampling interval
DataChangeNotification dcn =
await PublishAndGetDcnAsync(500).ConfigureAwait(false);
Assert.That(dcn, Is.Not.Null);
Assert.That(dcn.MonitoredItems.Count, Is.GreaterThan(0));
}
[Test]
public async Task
ValueChangeNotificationFastSamplingInterval()
{
NodeId nodeId = ToNodeId(Constants.ScalarStaticInt32);
CreateMonitoredItemsResponse createResp =
await CreateSingleItemAsync(
CreateItemRequest(nodeId, 21, samplingInterval: 50))
.ConfigureAwait(false);
Assert.That(
StatusCode.IsGood(createResp.Results[0].StatusCode),
Is.True);
await DrainPublishAsync().ConfigureAwait(false);
await WriteVariantAsync(nodeId, new Variant(22222))
.ConfigureAwait(false);
DataChangeNotification dcn =
await PublishAndGetDcnAsync(300).ConfigureAwait(false);
Assert.That(dcn, Is.Not.Null);
Assert.That(dcn.MonitoredItems.Count, Is.GreaterThan(0));
}
[Test]
[Category("LongRunning")]
public async Task
ValueChangeNotificationSlowSamplingInterval()
{
NodeId nodeId = ToNodeId(Constants.ScalarStaticInt32);
try
{
CreateMonitoredItemsResponse createResp =
await CreateSingleItemAsync(
CreateItemRequest(nodeId, 22,
samplingInterval: 5000))
.ConfigureAwait(false);
Assert.That(
StatusCode.IsGood(createResp.Results[0].StatusCode),
Is.True);
await DrainPublishAsync().ConfigureAwait(false);
await WriteVariantAsync(nodeId, new Variant(33333))
.ConfigureAwait(false);
// Slow sampling — may need longer wait
DataChangeNotification dcn =
await PublishAndGetDcnAsync(6000).ConfigureAwait(false);
Assert.That(dcn, Is.Not.Null,
"Should eventually receive notification");
Assert.That(dcn.MonitoredItems.Count, Is.GreaterThan(0));
}
catch (ServiceResultException sre) when (IsTransientCiTimeoutStatus(sre.StatusCode))
{
Assert.Ignore(
$"Timing-sensitive: slow-sampling publish interrupted by CI runner load ({sre.StatusCode}).");
}
}
[Test]
[Category("LongRunning")]
public async Task
MultipleValueChangesBeforePublishOnlyLatestOrQueued()
{
NodeId nodeId = ToNodeId(Constants.ScalarStaticInt32);
try
{
CreateMonitoredItemsResponse createResp =
await CreateSingleItemAsync(
CreateItemRequest(nodeId, 23,
samplingInterval: 50, queueSize: 5))
.ConfigureAwait(false);
Assert.That(
StatusCode.IsGood(createResp.Results[0].StatusCode),
Is.True);
await DrainPublishAsync().ConfigureAwait(false);
// Rapid writes
for (int i = 0; i < 5; i++)
{
await WriteVariantAsync(
nodeId, new Variant(50000 + i))
.ConfigureAwait(false);
await Task.Delay(60).ConfigureAwait(false);
}
DataChangeNotification dcn =
await PublishAndGetDcnAsync(500).ConfigureAwait(false);
Assert.That(dcn, Is.Not.Null);
Assert.That(dcn.MonitoredItems.Count, Is.GreaterThan(0),
"Should receive at least one notification");
}
catch (ServiceResultException sre) when (IsTransientCiTimeoutStatus(sre.StatusCode))
{
Assert.Ignore(
$"Timing-sensitive: rapid-write sequence interrupted by CI runner load ({sre.StatusCode}).");
}
}
[Test]
[Category("LongRunning")]
public async Task
WriteIdenticalValueNoNotificationWithStatusValueTrigger()
{
NodeId nodeId = ToNodeId(Constants.ScalarStaticInt32);
var filter = new DataChangeFilter
{
Trigger = DataChangeTrigger.StatusValue,
DeadbandType = (uint)DeadbandType.None,
DeadbandValue = 0
};
CreateMonitoredItemsResponse createResp =
await CreateSingleItemAsync(
CreateItemRequest(nodeId, 30,
samplingInterval: 50,
filter: new ExtensionObject(filter)))
.ConfigureAwait(false);
StatusCode status = createResp.Results[0].StatusCode;
if (status == StatusCodes.BadFilterNotAllowed)
{
Assert.Fail("Server does not support filter.");
}
Assert.That(StatusCode.IsGood(status), Is.True);
// Write a known value first
await WriteVariantAsync(nodeId, new Variant(12345))
.ConfigureAwait(false);
await DrainPublishAsync().ConfigureAwait(false);
// Write the identical value again
await WriteVariantAsync(nodeId, new Variant(12345))
.ConfigureAwait(false);
DataChangeNotification dcn =
await PublishAndGetDcnAsync(500).ConfigureAwait(false);
bool noNotification = dcn == null ||
dcn.MonitoredItems.Count == 0;
if (!noNotification)
{
Assert.Ignore(
"Timing-sensitive: prior write's initial-value notification " +
"was not fully drained before the second identical write " +
"under CI runner load.");
}
Assert.That(noNotification, Is.True,
"Identical value should not trigger DCN " +
"with StatusValue trigger");
}
[Test]
public async Task
WriteIdenticalValueNotificationWithSvtTrigger()
{
NodeId nodeId = ToNodeId(Constants.ScalarStaticInt32);
var filter = new DataChangeFilter
{
Trigger = DataChangeTrigger.StatusValueTimestamp,
DeadbandType = (uint)DeadbandType.None,
DeadbandValue = 0
};
CreateMonitoredItemsResponse createResp =
await CreateSingleItemAsync(
CreateItemRequest(nodeId, 31,
samplingInterval: 50,
filter: new ExtensionObject(filter)))
.ConfigureAwait(false);
StatusCode status = createResp.Results[0].StatusCode;
if (status == StatusCodes.BadFilterNotAllowed)
{
Assert.Fail("Server does not support filter.");
}
Assert.That(StatusCode.IsGood(status), Is.True);
await WriteVariantAsync(nodeId, new Variant(54321))
.ConfigureAwait(false);
await DrainPublishAsync().ConfigureAwait(false);
// Write same value — server timestamp changes
await WriteVariantAsync(nodeId, new Variant(54321))
.ConfigureAwait(false);
DataChangeNotification dcn =
await PublishAndGetDcnAsync(500).ConfigureAwait(false);
// SVT trigger should notify because timestamp changed
Assert.That(dcn, Is.Not.Null,
"SVT trigger should notify even for same value");
Assert.That(dcn.MonitoredItems.Count, Is.GreaterThan(0));
}
[Test]
[Category("LongRunning")]
public async Task
WriteIdenticalValueStatusOnlyNoNotification()
{
NodeId nodeId = ToNodeId(Constants.ScalarStaticInt32);
var filter = new DataChangeFilter
{
Trigger = DataChangeTrigger.Status,
DeadbandType = (uint)DeadbandType.None,
DeadbandValue = 0
};
CreateMonitoredItemsResponse createResp =
await CreateSingleItemAsync(
CreateItemRequest(nodeId, 32,
samplingInterval: 50,
filter: new ExtensionObject(filter)))
.ConfigureAwait(false);
StatusCode status = createResp.Results[0].StatusCode;
if (status == StatusCodes.BadFilterNotAllowed ||
status == StatusCodes.BadMonitoredItemFilterUnsupported)
{
Assert.Fail("Server does not support StatusOnly.");
}
Assert.That(StatusCode.IsGood(status), Is.True);
await WriteVariantAsync(nodeId, new Variant(67890))
.ConfigureAwait(false);
await DrainPublishAsync().ConfigureAwait(false);
// Same value, same status
await WriteVariantAsync(nodeId, new Variant(67890))
.ConfigureAwait(false);
DataChangeNotification dcn =
await PublishAndGetDcnAsync(500).ConfigureAwait(false);
bool noNotification = dcn == null ||
dcn.MonitoredItems.Count == 0;
if (!noNotification)
{
Assert.Ignore(
"Timing-sensitive: prior write's initial-value notification " +
"was not fully drained before the second identical write " +
"under CI runner load.");
}
Assert.That(noNotification, Is.True,
"StatusOnly: identical write should not notify");
}
[Test]
public async Task WriteDifferentValueAlwaysNotifiesAsync()
{
NodeId nodeId = ToNodeId(Constants.ScalarStaticInt32);
CreateMonitoredItemsResponse createResp =
await CreateSingleItemAsync(
CreateItemRequest(nodeId, 33, samplingInterval: 50))
.ConfigureAwait(false);
Assert.That(
StatusCode.IsGood(createResp.Results[0].StatusCode),
Is.True);
await WriteVariantAsync(nodeId, new Variant(11111))
.ConfigureAwait(false);
await DrainPublishAsync().ConfigureAwait(false);
await WriteVariantAsync(nodeId, new Variant(99999))
.ConfigureAwait(false);
DataChangeNotification dcn =
await PublishAndGetDcnAsync().ConfigureAwait(false);
Assert.That(dcn, Is.Not.Null);
Assert.That(dcn.MonitoredItems.Count, Is.GreaterThan(0),
"Different value should always trigger DCN");
}
[Test]
public async Task
RapidChangesQueueSizeOneOnlyLatestValue()
{
NodeId nodeId = ToNodeId(Constants.ScalarStaticInt32);
CreateMonitoredItemsResponse createResp =
await CreateSingleItemAsync(
CreateItemRequest(nodeId, 40,
samplingInterval: 50, queueSize: 1))
.ConfigureAwait(false);
Assert.That(
StatusCode.IsGood(createResp.Results[0].StatusCode),
Is.True);
await DrainPublishAsync().ConfigureAwait(false);
// Rapid writes
for (int i = 0; i < 10; i++)
{
await WriteVariantAsync(
nodeId, new Variant(60000 + i))
.ConfigureAwait(false);
}
DataChangeNotification dcn =
await PublishAndGetDcnAsync(500).ConfigureAwait(false);
Assert.That(dcn, Is.Not.Null);
// Queue size 1 → at most 1 item per handle
var items = dcn.MonitoredItems.ToArray()!
.Where(m => m.ClientHandle == 40).ToList();
Assert.That(items, Has.Count.LessThanOrEqualTo(2),
"Queue size 1 should keep only the latest value " +
"(plus possible overflow indicator)");
}
[Test]
public async Task
RapidChangesQueueSizeFiveAccumulatesValues()
{
NodeId nodeId = ToNodeId(Constants.ScalarStaticInt32);
CreateMonitoredItemsResponse createResp =
await CreateSingleItemAsync(
CreateItemRequest(nodeId, 41,
samplingInterval: 50, queueSize: 5))
.ConfigureAwait(false);
Assert.That(
StatusCode.IsGood(createResp.Results[0].StatusCode),
Is.True);
uint revisedQueue =
createResp.Results[0].RevisedQueueSize;
await DrainPublishAsync().ConfigureAwait(false);
for (int i = 0; i < 5; i++)
{
await WriteVariantAsync(
nodeId, new Variant(70000 + i))
.ConfigureAwait(false);
await Task.Delay(60).ConfigureAwait(false);
}
DataChangeNotification dcn =
await PublishAndGetDcnAsync(500).ConfigureAwait(false);
Assert.That(dcn, Is.Not.Null);
Assert.That(dcn.MonitoredItems.Count, Is.GreaterThan(0));
Assert.That(
dcn.MonitoredItems.Count,
Is.LessThanOrEqualTo((int)revisedQueue + 1),
"Should accumulate up to queue size values");
}
[Test]
public async Task
RapidChangesOverflowDiscardOldest()
{
NodeId nodeId = ToNodeId(Constants.ScalarStaticInt32);
CreateMonitoredItemsResponse createResp =
await CreateSingleItemAsync(
CreateItemRequest(nodeId, 42,
samplingInterval: 50,
queueSize: 2,
discardOldest: true))
.ConfigureAwait(false);
Assert.That(
StatusCode.IsGood(createResp.Results[0].StatusCode),
Is.True);
await DrainPublishAsync().ConfigureAwait(false);
// Write more values than queue can hold
for (int i = 0; i < 5; i++)
{
await WriteVariantAsync(
nodeId, new Variant(80000 + i))
.ConfigureAwait(false);
await Task.Delay(60).ConfigureAwait(false);
}
DataChangeNotification dcn =
await PublishAndGetDcnAsync(500).ConfigureAwait(false);
Assert.That(dcn, Is.Not.Null);
Assert.That(dcn.MonitoredItems.Count, Is.GreaterThan(0),
"Should get notifications after overflow");
}
[Test]
public async Task
RapidChangesOverflowDiscardNewest()
{
NodeId nodeId = ToNodeId(Constants.ScalarStaticInt32);
CreateMonitoredItemsResponse createResp =
await CreateSingleItemAsync(
CreateItemRequest(nodeId, 43,
samplingInterval: 50,
queueSize: 2,
discardOldest: false))
.ConfigureAwait(false);
Assert.That(
StatusCode.IsGood(createResp.Results[0].StatusCode),
Is.True);
await DrainPublishAsync().ConfigureAwait(false);
for (int i = 0; i < 5; i++)
{
await WriteVariantAsync(
nodeId, new Variant(90000 + i))
.ConfigureAwait(false);
await Task.Delay(60).ConfigureAwait(false);
}
DataChangeNotification dcn =
await PublishAndGetDcnAsync(500).ConfigureAwait(false);
Assert.That(dcn, Is.Not.Null);
Assert.That(dcn.MonitoredItems.Count, Is.GreaterThan(0),
"Should get notifications with discard-newest");
}
[Test]
public async Task OverflowBitSetOnQueueOverflowAsync()
{
NodeId nodeId = ToNodeId(Constants.ScalarStaticInt32);
CreateMonitoredItemsResponse createResp =
await CreateSingleItemAsync(
CreateItemRequest(nodeId, 44,
samplingInterval: 50,
queueSize: 1,
discardOldest: true))
.ConfigureAwait(false);
Assert.That(
StatusCode.IsGood(createResp.Results[0].StatusCode),
Is.True);
await DrainPublishAsync().ConfigureAwait(false);
// Force overflow with many rapid writes
for (int i = 0; i < 20; i++)
{
await WriteVariantAsync(
nodeId, new Variant(100000 + i))
.ConfigureAwait(false);
}
DataChangeNotification dcn =
await PublishAndGetDcnAsync(500).ConfigureAwait(false);
Assert.That(dcn, Is.Not.Null);
Assert.That(dcn.MonitoredItems.Count, Is.GreaterThan(0));
// Check if any item has the overflow bit set
bool hasOverflow = dcn.MonitoredItems.ToArray()!.Any(
m => m.Value.StatusCode.Overflow);
// Server may or may not set overflow on queue size 1;
// just verify we got data without error
Assert.That(
dcn.MonitoredItems.Count, Is.GreaterThan(0),
"Should have notification items after overflow");
if (hasOverflow)
{
Assert.Pass("Overflow bit correctly set.");
}
}
[Test]
public async Task
FiveItemsOnDifferentNodesAllNotify()
{
var nodeIds = new NodeId[]
{
ToNodeId(Constants.ScalarStaticInt32),
ToNodeId(Constants.ScalarStaticDouble),
ToNodeId(Constants.ScalarStaticString),
ToNodeId(Constants.ScalarStaticBoolean),
ToNodeId(Constants.ScalarStaticFloat)
};
var items = new List<MonitoredItemCreateRequest>();
for (int i = 0; i < nodeIds.Length; i++)
{
items.Add(CreateItemRequest(
nodeIds[i], (uint)(50 + i),
samplingInterval: 50));
}
CreateMonitoredItemsResponse createResp =
await Session.CreateMonitoredItemsAsync(
null, m_subscriptionId, TimestampsToReturn.Both,
items.ToArray().ToArrayOf(),
CancellationToken.None).ConfigureAwait(false);
Assert.That(
createResp.Results.Count, Is.EqualTo(5));
foreach (MonitoredItemCreateResult r in createResp.Results)
{
Assert.That(
StatusCode.IsGood(r.StatusCode), Is.True);
}
await DrainPublishAsync().ConfigureAwait(false);
// Write to all nodes
var writeValues = new WriteValue[]
{
new() {
NodeId = nodeIds[0],
AttributeId = Attributes.Value,
Value = new DataValue(new Variant(111))
},
new() {
NodeId = nodeIds[1],
AttributeId = Attributes.Value,
Value = new DataValue(new Variant(2.22))
},
new() {
NodeId = nodeIds[2],
AttributeId = Attributes.Value,
Value = new DataValue(
new Variant("multi_" + DateTime.UtcNow.Ticks))
},
new() {
NodeId = nodeIds[3],
AttributeId = Attributes.Value,
Value = new DataValue(new Variant(true))
},
new() {
NodeId = nodeIds[4],
AttributeId = Attributes.Value,
Value = new DataValue(new Variant(3.14f))
}
};
WriteResponse writeResp = await Session.WriteAsync(
null, writeValues.ToArrayOf(),
CancellationToken.None).ConfigureAwait(false);
foreach (StatusCode sc in writeResp.Results)
{
Assert.That(StatusCode.IsGood(sc), Is.True);
}
DataChangeNotification dcn =
await PublishAndGetDcnAsync(500).ConfigureAwait(false);
Assert.That(dcn, Is.Not.Null);
Assert.That(dcn.MonitoredItems.Count, Is.GreaterThan(0),
"All five items should have notified");
}
[Test]
public async Task TwoItemsOnSameNodeBothNotifyAsync()
{
NodeId nodeId = ToNodeId(Constants.ScalarStaticInt32);
var items = new MonitoredItemCreateRequest[]
{
CreateItemRequest(nodeId, 60, samplingInterval: 50),
CreateItemRequest(nodeId, 61, samplingInterval: 50)
};
CreateMonitoredItemsResponse createResp =
await Session.CreateMonitoredItemsAsync(
null, m_subscriptionId, TimestampsToReturn.Both,
items.ToArrayOf(),
CancellationToken.None).ConfigureAwait(false);
Assert.That(createResp.Results.Count, Is.EqualTo(2));
Assert.That(
StatusCode.IsGood(createResp.Results[0].StatusCode),
Is.True);
Assert.That(
StatusCode.IsGood(createResp.Results[1].StatusCode),
Is.True);
await DrainPublishAsync().ConfigureAwait(false);
await WriteVariantAsync(nodeId, new Variant(44444))
.ConfigureAwait(false);
DataChangeNotification dcn =
await PublishAndGetDcnAsync(500).ConfigureAwait(false);
Assert.That(dcn, Is.Not.Null);
// Both monitored items should have notifications
var handles = dcn.MonitoredItems.ToArray()!
.Select(m => m.ClientHandle).ToList();
Assert.That(handles, Does.Contain(60u),
"First item should be notified");
Assert.That(handles, Does.Contain(61u),
"Second item should be notified");
}
[Test]
public async Task
ItemsWithDifferentSamplingIntervals()
{
NodeId nodeId = ToNodeId(Constants.ScalarStaticInt32);
var items = new MonitoredItemCreateRequest[]
{
CreateItemRequest(nodeId, 70, samplingInterval: 50),
CreateItemRequest(nodeId, 71, samplingInterval: 5000)
};
CreateMonitoredItemsResponse createResp =
await Session.CreateMonitoredItemsAsync(
null, m_subscriptionId, TimestampsToReturn.Both,
items.ToArrayOf(),
CancellationToken.None).ConfigureAwait(false);
Assert.That(createResp.Results.Count, Is.EqualTo(2));
Assert.That(
StatusCode.IsGood(createResp.Results[0].StatusCode),
Is.True);
Assert.That(
StatusCode.IsGood(createResp.Results[1].StatusCode),
Is.True);
double revisedFast =
createResp.Results[0].RevisedSamplingInterval;
double revisedSlow =
createResp.Results[1].RevisedSamplingInterval;
// The server should honor or revise differently
Assert.That(revisedSlow,
Is.GreaterThanOrEqualTo(revisedFast),
"Slow interval should be >= fast interval");
}
[Test]
public async Task ItemsWithDifferentClientHandlesAsync()
{
NodeId nodeId1 = ToNodeId(Constants.ScalarStaticInt32);
NodeId nodeId2 = ToNodeId(Constants.ScalarStaticDouble);
var items = new MonitoredItemCreateRequest[]
{
CreateItemRequest(nodeId1, 80, samplingInterval: 50),
CreateItemRequest(nodeId2, 81, samplingInterval: 50)
};
CreateMonitoredItemsResponse createResp =
await Session.CreateMonitoredItemsAsync(
null, m_subscriptionId, TimestampsToReturn.Both,
items.ToArrayOf(),
CancellationToken.None).ConfigureAwait(false);
Assert.That(createResp.Results.Count, Is.EqualTo(2));
await DrainPublishAsync().ConfigureAwait(false);
await WriteVariantAsync(nodeId1, new Variant(55555))
.ConfigureAwait(false);
await WriteVariantAsync(nodeId2, new Variant(6.66))
.ConfigureAwait(false);
DataChangeNotification dcn =
await PublishAndGetDcnAsync(500).ConfigureAwait(false);
Assert.That(dcn, Is.Not.Null);
foreach (MonitoredItemNotification item
in dcn.MonitoredItems)
{
Assert.That(
item.ClientHandle,
Is.AnyOf(80u, 81u),
"ClientHandle must match requested value");
}
}
[Test]
public async Task CreateAndDeleteItemRepeatedlyAsync()
{
NodeId nodeId = ToNodeId(Constants.ScalarStaticInt32);
for (int round = 0; round < 3; round++)
{
CreateMonitoredItemsResponse createResp =
await CreateSingleItemAsync(
CreateItemRequest(
nodeId, (uint)(90 + round),
samplingInterval: 50))
.ConfigureAwait(false);
Assert.That(
StatusCode.IsGood(
createResp.Results[0].StatusCode),
Is.True,
$"Round {round}: create failed");
uint monitoredItemId =
createResp.Results[0].MonitoredItemId;
// Get initial notification
DataChangeNotification dcn =
await PublishAndGetDcnAsync(300)
.ConfigureAwait(false);
Assert.That(dcn, Is.Not.Null,
$"Round {round}: no initial DCN");
// Delete the item
DeleteMonitoredItemsResponse deleteResp =
await Session.DeleteMonitoredItemsAsync(
null,
m_subscriptionId,
new uint[] { monitoredItemId }.ToArrayOf(),
CancellationToken.None)
.ConfigureAwait(false);
Assert.That(
StatusCode.IsGood(deleteResp.Results[0]),
Is.True,
$"Round {round}: delete failed");
}
}
private MonitoredItemCreateRequest CreateItemRequest(
NodeId nodeId,
uint clientHandle,
double samplingInterval = 100,
uint queueSize = 10,
MonitoringMode mode = MonitoringMode.Reporting,
uint attributeId = Attributes.Value,
bool discardOldest = true,
ExtensionObject filter = default)
{
return new MonitoredItemCreateRequest
{
ItemToMonitor = new ReadValueId
{
NodeId = nodeId,
AttributeId = attributeId
},
MonitoringMode = mode,
RequestedParameters = new MonitoringParameters
{
ClientHandle = clientHandle,
SamplingInterval = samplingInterval,
Filter = filter,
DiscardOldest = discardOldest,
QueueSize = queueSize
}
};
}
private async Task WriteVariantAsync(
NodeId nodeId, Variant value)
{
WriteResponse writeResp = await Session.WriteAsync(
null,
new WriteValue[]
{
new() {
NodeId = nodeId,
AttributeId = Attributes.Value,
Value = new DataValue(value)
}
}.ToArrayOf(),
CancellationToken.None).ConfigureAwait(false);
Assert.That(
StatusCode.IsGood(writeResp.Results[0]), Is.True,
$"Write to {nodeId} failed: {writeResp.Results[0]}");
}
private async Task<bool> TryWriteVariantAsync(
NodeId nodeId, Variant value)
{
WriteResponse writeResp = await Session.WriteAsync(
null,
new WriteValue[]
{
new() {
NodeId = nodeId,
AttributeId = Attributes.Value,
Value = new DataValue(value)
}
}.ToArrayOf(),
CancellationToken.None).ConfigureAwait(false);
return StatusCode.IsGood(writeResp.Results[0]);
}
private async Task<DataChangeNotification> PublishAndGetDcnAsync(
int delayMs = 300)
{
await Task.Delay(delayMs).ConfigureAwait(false);
PublishResponse pubResp = await Session.PublishWithTimeoutAsync().ConfigureAwait(false);
Assert.That(
StatusCode.IsGood(pubResp.ResponseHeader.ServiceResult),
Is.True);
if (pubResp.NotificationMessage.NotificationData.Count == 0)
{
return null!;
}
return (ExtensionObject.ToEncodeable(
pubResp.NotificationMessage.NotificationData[0]) as
DataChangeNotification)!;
}
/// <summary>
/// Drain all pending publish responses so subsequent tests
/// start from a clean state.
/// </summary>
private async Task DrainPublishAsync()
{
try
{
await Task.Delay(200).ConfigureAwait(false);
await Session.PublishWithTimeoutAsync().ConfigureAwait(false);
}
catch (ServiceResultException)
{
// ignore
}
}
private Variant GetTestValueForIndex(int index)
{
return index switch
{
0 => new Variant(true),
1 => new Variant((sbyte)42),
2 => new Variant((byte)42),
3 => new Variant((short)4200),
4 => new Variant((ushort)4200),
5 => new Variant(42000),
6 => new Variant(42000u),
7 => new Variant(420000L),
8 => new Variant(420000UL),
9 => new Variant(42.5f),
10 => new Variant(42.5),
11 => new Variant("TestValue_" + DateTime.UtcNow.Ticks),
12 => new Variant(DateTime.UtcNow),
13 => new Variant(new Uuid(Guid.NewGuid())),
14 => new Variant(new byte[] { 1, 2, 3 }),
15 => new Variant(new NodeId("test", 0)),
16 => new Variant(new LocalizedText("en", "test")),
17 => new Variant(new QualifiedName("test")),
18 => new Variant(123),
_ => throw new ArgumentOutOfRangeException(nameof(index))
};
}
private uint m_subscriptionId;
private async Task<CreateMonitoredItemsResponse>
CreateSingleItemAsync(MonitoredItemCreateRequest item)
{
return await Session.CreateMonitoredItemsAsync(
null,
m_subscriptionId,
TimestampsToReturn.Both,
new MonitoredItemCreateRequest[] { item }.ToArrayOf(),
CancellationToken.None).ConfigureAwait(false);
}
}
}