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#pragma warning disable CA2016
using System;
using System.Collections.Generic;
using System.IO;
using System.Threading;
using System.Threading.Tasks;
using NUnit.Framework;
using Opc.Ua.Client;
using Opc.Ua.Client.Subscriptions;
using Opc.Ua.Client.Subscriptions.MonitoredItems;
using Opc.Ua.Client.TestFramework;
namespace Opc.Ua.Subscriptions.Tests
{
///
/// V2 follow-up coverage: handler state-change callback,
/// fluent stream-based LoadSubscriptionsAsync, SendInitialValuesOnTransfer
/// behavior, snapshot edge cases (empty / with-filter / concurrent).
///
[TestFixture]
[Category("Client")]
[Category("V2")]
[Category("FollowUp")]
[SetCulture("en-us")]
[SetUICulture("en-us")]
public class SubscriptionCoverageTests : ClientTestFramework
{
[OneTimeSetUp]
public override Task OneTimeSetUpAsync()
{
SupportsExternalServerUrl = true;
SingleSession = false;
return OneTimeSetUpCoreAsync(securityNone: true);
}
[OneTimeTearDown]
public override Task OneTimeTearDownAsync()
{
return base.OneTimeTearDownAsync();
}
[SetUp]
public override Task SetUpAsync()
{
return base.SetUpAsync();
}
[TearDown]
public override Task TearDownAsync()
{
return base.TearDownAsync();
}
[Test]
[Order(100)]
[CancelAfter(60_000)]
public async Task HandlerStateChangedFiresOnLifecycleV2Async(
CancellationToken ct)
{
ManagedSession session = await ConnectV2Async(
nameof(HandlerStateChangedFiresOnLifecycleV2Async), ct)
.ConfigureAwait(false);
try
{
var handler = new RecordingSubscriptionHandler();
ISubscription sub = session.AddSubscription(handler,
new Client.Subscriptions.SubscriptionOptions
{
PublishingInterval = TimeSpan.FromMilliseconds(500),
KeepAliveCount = 10,
LifetimeCount = 100,
PublishingEnabled = true
});
bool created = await WaitForAsync(() => sub.Created,
TimeSpan.FromSeconds(10), ct).ConfigureAwait(false);
Assert.That(created, Is.True);
bool sawStateChanges = await WaitForAsync(
() => handler.StateChangedCount > 0,
TimeSpan.FromSeconds(10), ct).ConfigureAwait(false);
Assert.That(sawStateChanges, Is.True,
"OnSubscriptionStateChangedAsync should fire during subscription lifecycle");
IReadOnlyList snap = handler.GetStateChangeSnapshot();
Assert.That(snap, Is.Not.Empty);
// Sub-test: derive a "is currently created" indicator from
// the callback stream — proves the handler-maintains-state
// pattern that replaced the dropped PublishingStopped
// property on ISubscription.
bool sawCreated = false;
foreach (RecordedStateChange c in snap)
{
if (c.State is Client.Subscriptions.SubscriptionState.Created or
Client.Subscriptions.SubscriptionState.Modified or
Client.Subscriptions.SubscriptionState.Opened)
{
sawCreated = true;
}
}
Assert.That(sawCreated, Is.True,
"State stream should include at least one Created / " +
"Modified / Opened transition");
await sub.DisposeAsync().ConfigureAwait(false);
}
finally
{
await session.CloseAsync().ConfigureAwait(false);
await session.DisposeAsync().ConfigureAwait(false);
}
}
[Test]
[Order(200)]
[CancelAfter(60_000)]
public async Task FluentLoadSubscriptionsAsyncStreamV2Async(
CancellationToken ct)
{
ManagedSession originSession = await ConnectV2Async(
nameof(FluentLoadSubscriptionsAsyncStreamV2Async) + "_origin", ct)
.ConfigureAwait(false);
ManagedSession? targetSession = null;
try
{
var originHandler = new RecordingSubscriptionHandler();
ISubscription origin = originSession.AddSubscription(originHandler,
new Client.Subscriptions.SubscriptionOptions
{
PublishingInterval = TimeSpan.FromMilliseconds(500),
KeepAliveCount = 10,
LifetimeCount = 100,
PublishingEnabled = true
});
Assert.That(await WaitForAsync(() => origin.Created,
TimeSpan.FromSeconds(10), ct).ConfigureAwait(false), Is.True);
Assert.That(origin.TryAddMonitoredItem("Time",
VariableIds.Server_ServerStatus_CurrentTime,
o => o with { SamplingInterval = TimeSpan.FromMilliseconds(200) },
out _), Is.True);
Assert.That(await originHandler.WaitForFirstDataAsync(
TimeSpan.FromSeconds(10), ct).ConfigureAwait(false), Is.True);
using var ms = new MemoryStream();
await originSession.SaveSubscriptionsAsync(ms, ct: ct)
.ConfigureAwait(false);
byte[] saved = ms.ToArray();
Assert.That(saved, Has.Length.GreaterThan(0));
targetSession = await ConnectV2Async(
nameof(FluentLoadSubscriptionsAsyncStreamV2Async) + "_target", ct)
.ConfigureAwait(false);
var targetHandler = new RecordingSubscriptionHandler();
using var input = new MemoryStream(saved);
IReadOnlyList loaded = await targetSession
.LoadSubscriptionsAsync(input, _ => targetHandler,
transferSubscriptions: false, ct)
.ConfigureAwait(false);
Assert.That(loaded, Has.Count.EqualTo(1));
Assert.That(await WaitForAsync(() => loaded[0].Created,
TimeSpan.FromSeconds(15), ct).ConfigureAwait(false), Is.True);
Assert.That(await targetHandler.WaitForFirstDataAsync(
TimeSpan.FromSeconds(15), ct).ConfigureAwait(false), Is.True);
await loaded[0].DisposeAsync().ConfigureAwait(false);
await origin.DisposeAsync().ConfigureAwait(false);
}
finally
{
try
{
await originSession.CloseAsync().ConfigureAwait(false);
}
catch
{ /* best effort */
}
try
{
await originSession.DisposeAsync().ConfigureAwait(false);
}
catch
{ /* best effort */
}
if (targetSession != null)
{
try
{
await targetSession.CloseAsync().ConfigureAwait(false);
}
catch
{ /* best effort */
}
try
{
await targetSession.DisposeAsync().ConfigureAwait(false);
}
catch
{ /* best effort */
}
}
}
}
[Test]
[Order(300)]
[CancelAfter(60_000)]
public async Task SendInitialValuesOnTransferV2Async(CancellationToken ct)
{
// When the test runs against a reference server that denies
// cross-anonymous-session transfer with BadUserAccessDenied,
// the V2 manager falls back to recreate. Recreate always
// delivers an initial value (server first-sample behavior),
// so the SendInitialValuesOnTransfer option's effect can't
// be distinguished. Document that and verify the option
// propagates structurally + the subscription works after
// restore regardless of which path the server took.
string saveFile = Path.Combine(Path.GetTempPath(),
$"V2InitVals-{Guid.NewGuid():N}.bin");
ManagedSession originSession = await ConnectV2Async(
nameof(SendInitialValuesOnTransferV2Async) + "_origin", ct)
.ConfigureAwait(false);
originSession.DeleteSubscriptionsOnClose = false;
ManagedSession? targetSession = null;
try
{
var originHandler = new RecordingSubscriptionHandler();
ISubscription origin = originSession.AddSubscription(originHandler,
new Client.Subscriptions.SubscriptionOptions
{
PublishingInterval = TimeSpan.FromMilliseconds(500),
KeepAliveCount = 10,
LifetimeCount = 100,
PublishingEnabled = true,
SendInitialValuesOnTransfer = true
});
Assert.That(await WaitForAsync(() => origin.Created,
TimeSpan.FromSeconds(10), ct).ConfigureAwait(false), Is.True);
Assert.That(origin.TryAddMonitoredItem("Time",
VariableIds.Server_ServerStatus_CurrentTime,
o => o with { SamplingInterval = TimeSpan.FromMilliseconds(200) },
out _), Is.True);
Assert.That(await originHandler.WaitForFirstDataAsync(
TimeSpan.FromSeconds(10), ct).ConfigureAwait(false), Is.True);
// Snapshot includes the SendInitialValuesOnTransfer
// option through SubscriptionStateSnapshot.ToOptions().
SubscriptionStateSnapshot snap = ((LogicalSubscription)origin).Snapshot();
Assert.That(snap.SendInitialValuesOnTransfer, Is.True,
"SendInitialValuesOnTransfer option must round-trip through Snapshot");
using (FileStream output = File.Create(saveFile))
{
await originSession.SaveSubscriptionsAsync(output, ct: ct)
.ConfigureAwait(false);
}
StatusCode originClose = await originSession.CloseAsync()
.ConfigureAwait(false);
// The origin session is closed WITHOUT deleting its subscriptions
// (DeleteSubscriptionsOnClose == false) so the target can take
// them over. On a loaded CI agent the deliberate close can race
// the transfer/state-manager and the inner Session.CloseAsync
// then returns the interrupted/invalidated status instead of
// Good. That close-time race is benign here - the subscription
// state was already persisted to saveFile above and is retained
// server-side - so accept those transient statuses. The strict
// end-to-end proof is the load + transfer + data flow on the
// fresh target session below, which is unchanged.
bool closeAcceptable = ServiceResult.IsGood(originClose) ||
originClose.Code == (uint)StatusCodes.BadSessionIdInvalid ||
originClose.Code == (uint)StatusCodes.BadRequestInterrupted ||
originClose.Code == (uint)StatusCodes.BadConnectionClosed ||
originClose.Code == (uint)StatusCodes.BadSecureChannelClosed ||
originClose.Code == (uint)StatusCodes.BadServerHalted;
Assert.That(closeAcceptable, Is.True,
"Unexpected origin close status: " + originClose.ToString());
targetSession = await ConnectV2Async(
nameof(SendInitialValuesOnTransferV2Async) + "_target", ct)
.ConfigureAwait(false);
var targetHandler = new RecordingSubscriptionHandler();
using FileStream input = File.OpenRead(saveFile);
IReadOnlyList loaded = await targetSession
.LoadSubscriptionsAsync(input, _ => targetHandler,
transferSubscriptions: true, ct)
.ConfigureAwait(false);
Assert.That(loaded, Has.Count.EqualTo(1));
bool gotData = await targetHandler.WaitForFirstDataAsync(
TimeSpan.FromSeconds(15), ct).ConfigureAwait(false);
Assert.That(gotData, Is.True,
"Target subscription should publish (transfer or recreate)");
await loaded[0].DisposeAsync().ConfigureAwait(false);
}
finally
{
try
{
await originSession.DisposeAsync().ConfigureAwait(false);
}
catch
{ /* best effort */
}
if (targetSession != null)
{
try
{
await targetSession.CloseAsync().ConfigureAwait(false);
}
catch
{ /* best effort */
}
try
{
await targetSession.DisposeAsync().ConfigureAwait(false);
}
catch
{ /* best effort */
}
}
try
{
File.Delete(saveFile);
}
catch
{ /* best effort */
}
}
}
[Test]
[Order(400)]
[CancelAfter(60_000)]
public async Task SnapshotEmptySubscriptionRoundTripV2Async(
CancellationToken ct)
{
ManagedSession session = await ConnectV2Async(
nameof(SnapshotEmptySubscriptionRoundTripV2Async), ct)
.ConfigureAwait(false);
ManagedSession? target = null;
try
{
var handler = new RecordingSubscriptionHandler();
ISubscription sub = session.AddSubscription(handler,
new Client.Subscriptions.SubscriptionOptions
{
PublishingInterval = TimeSpan.FromMilliseconds(500),
KeepAliveCount = 10,
LifetimeCount = 100,
PublishingEnabled = true
});
Assert.That(await WaitForAsync(() => sub.Created,
TimeSpan.FromSeconds(10), ct).ConfigureAwait(false), Is.True);
Assert.That(sub.MonitoredItems.Count, Is.Zero);
SubscriptionStateSnapshot snap = ((LogicalSubscription)sub).Snapshot();
Assert.That(snap.MonitoredItems.Count, Is.Zero);
target = await ConnectV2Async(
nameof(SnapshotEmptySubscriptionRoundTripV2Async) + "_target", ct)
.ConfigureAwait(false);
ISubscriptionManager targetManager = target.RequireSubscriptionManager();
Assert.That(targetManager, Is.InstanceOf());
ISubscription restored = await ((SubscriptionManager)targetManager)
.RestoreAsync(
new RecordingSubscriptionHandler(),
snap,
transferSubscriptions: false,
ct)
.ConfigureAwait(false);
Assert.That(await WaitForAsync(() => restored.Created,
TimeSpan.FromSeconds(10), ct).ConfigureAwait(false), Is.True);
Assert.That(restored.MonitoredItems.Count, Is.Zero);
await restored.DisposeAsync().ConfigureAwait(false);
await sub.DisposeAsync().ConfigureAwait(false);
}
finally
{
try
{
await session.CloseAsync().ConfigureAwait(false);
}
catch
{ /* best effort */
}
try
{
await session.DisposeAsync().ConfigureAwait(false);
}
catch
{ /* best effort */
}
if (target != null)
{
try
{
await target.CloseAsync().ConfigureAwait(false);
}
catch
{ /* best effort */
}
try
{
await target.DisposeAsync().ConfigureAwait(false);
}
catch
{ /* best effort */
}
}
}
}
[Test]
[Order(500)]
[CancelAfter(60_000)]
public async Task SnapshotWithDataChangeFilterRoundTripV2Async(
CancellationToken ct)
{
ManagedSession session = await ConnectV2Async(
nameof(SnapshotWithDataChangeFilterRoundTripV2Async), ct)
.ConfigureAwait(false);
ManagedSession? target = null;
try
{
var handler = new RecordingSubscriptionHandler();
ISubscription sub = session.AddSubscription(handler,
new Client.Subscriptions.SubscriptionOptions
{
PublishingInterval = TimeSpan.FromMilliseconds(500),
KeepAliveCount = 10,
LifetimeCount = 100,
PublishingEnabled = true
});
Assert.That(await WaitForAsync(() => sub.Created,
TimeSpan.FromSeconds(10), ct).ConfigureAwait(false), Is.True);
var dataChangeFilter = new DataChangeFilter
{
Trigger = DataChangeTrigger.StatusValueTimestamp,
DeadbandType = (uint)DeadbandType.None,
DeadbandValue = 0.0
};
Assert.That(sub.TryAddMonitoredItem("Trigger",
VariableIds.Server_ServerStatus_CurrentTime,
o => o with
{
SamplingInterval = TimeSpan.FromMilliseconds(250),
Filter = dataChangeFilter
},
out IMonitoredItem? item), Is.True);
Assert.That(await WaitForAsync(() => item!.Created,
TimeSpan.FromSeconds(10), ct).ConfigureAwait(false), Is.True);
SubscriptionStateSnapshot snap = ((LogicalSubscription)sub).Snapshot();
Assert.That(snap.MonitoredItems.Count, Is.EqualTo(1));
MonitoredItemStateSnapshot itemSnap = snap.MonitoredItems[0];
Assert.That(itemSnap.Filter, Is.Not.Null);
Assert.That(itemSnap.Filter, Is.InstanceOf());
var restoredFilter = (DataChangeFilter)itemSnap.Filter!;
Assert.That(restoredFilter.Trigger,
Is.EqualTo(dataChangeFilter.Trigger));
Assert.That(restoredFilter.DeadbandType,
Is.EqualTo(dataChangeFilter.DeadbandType));
// Round-trip through the manager
target = await ConnectV2Async(
nameof(SnapshotWithDataChangeFilterRoundTripV2Async) + "_target", ct)
.ConfigureAwait(false);
ISubscriptionManager targetManager = target.RequireSubscriptionManager();
Assert.That(targetManager, Is.InstanceOf());
ISubscription restored = await ((SubscriptionManager)targetManager)
.RestoreAsync(
new RecordingSubscriptionHandler(),
snap,
transferSubscriptions: false,
ct)
.ConfigureAwait(false);
Assert.That(await WaitForAsync(() => restored.Created,
TimeSpan.FromSeconds(10), ct).ConfigureAwait(false), Is.True);
Assert.That(restored.MonitoredItems.Count, Is.EqualTo(1u));
await restored.DisposeAsync().ConfigureAwait(false);
await sub.DisposeAsync().ConfigureAwait(false);
}
finally
{
try
{
await session.CloseAsync().ConfigureAwait(false);
}
catch
{ /* best effort */
}
try
{
await session.DisposeAsync().ConfigureAwait(false);
}
catch
{ /* best effort */
}
if (target != null)
{
try
{
await target.CloseAsync().ConfigureAwait(false);
}
catch
{ /* best effort */
}
try
{
await target.DisposeAsync().ConfigureAwait(false);
}
catch
{ /* best effort */
}
}
}
}
[Test]
[Order(600)]
[CancelAfter(60_000)]
public async Task SnapshotUnderConcurrentMutationV2Async(
CancellationToken ct)
{
ManagedSession session = await ConnectV2Async(
nameof(SnapshotUnderConcurrentMutationV2Async), ct)
.ConfigureAwait(false);
try
{
var handler = new RecordingSubscriptionHandler();
ISubscription sub = session.AddSubscription(handler,
new Client.Subscriptions.SubscriptionOptions
{
PublishingInterval = TimeSpan.FromMilliseconds(500),
KeepAliveCount = 10,
LifetimeCount = 100,
PublishingEnabled = true
});
Assert.That(await WaitForAsync(() => sub.Created,
TimeSpan.FromSeconds(10), ct).ConfigureAwait(false), Is.True);
// Concurrently add items while taking snapshots. The
// snapshot must always return an internally consistent
// count (the names must all exist) — proves the
// manager-lock contract.
const int itemCount = 20;
var addTasks = new Task[itemCount];
for (int i = 0; i < itemCount; i++)
{
int idx = i;
addTasks[i] = Task.Run(() => sub.TryAddMonitoredItem(
string.Format(System.Globalization.CultureInfo.InvariantCulture,
"item-{0}", idx),
VariableIds.Server_ServerStatus_CurrentTime,
o => o with { SamplingInterval = TimeSpan.Zero },
out _), ct);
}
var subConcrete = (LogicalSubscription)sub;
var snapTasks = new Task[5];
for (int i = 0; i < snapTasks.Length; i++)
{
snapTasks[i] = Task.Run(() => subConcrete.Snapshot(), ct);
}
await Task.WhenAll(addTasks).ConfigureAwait(false);
SubscriptionStateSnapshot[] snaps = await Task
.WhenAll(snapTasks).ConfigureAwait(false);
foreach (SubscriptionStateSnapshot s in snaps)
{
int count = s.MonitoredItems.Count;
// Snapshot is captured at a point in time — count is
// between 0 and itemCount inclusive. The critical
// invariant: each captured item has a non-empty name
// (i.e. no partially-constructed entries leaked).
foreach (MonitoredItemStateSnapshot it in s.MonitoredItems)
{
Assert.That(it.Name, Is.Not.Null.And.Not.Empty);
}
}
Assert.That(sub.MonitoredItems.Count, Is.EqualTo((uint)itemCount));
await sub.DisposeAsync().ConfigureAwait(false);
}
finally
{
await session.CloseAsync().ConfigureAwait(false);
await session.DisposeAsync().ConfigureAwait(false);
}
}
private async Task ConnectV2Async(
string sessionName, CancellationToken ct)
{
ConfiguredEndpoint endpoint = await ClientFixture
.GetEndpointAsync(ServerUrl, SecurityPolicies.None)
.ConfigureAwait(false);
return await new ManagedSessionBuilder(ClientFixture.Config, Telemetry)
.UseEndpoint(endpoint)
.WithSessionName(sessionName)
.WithSessionTimeout(TimeSpan.FromSeconds(120))
.ConnectAsync(ct).ConfigureAwait(false);
}
private static async Task WaitForAsync(
Func predicate, TimeSpan timeout, CancellationToken ct)
{
DateTime deadline = DateTime.UtcNow + timeout;
while (DateTime.UtcNow < deadline)
{
ct.ThrowIfCancellationRequested();
if (predicate())
{
return true;
}
await Task.Delay(50, ct).ConfigureAwait(false);
}
return predicate();
}
}
}