# Description
V2 subscription engine feature parity round to make the classic engine
eligible for deprecation. Splits the test surface so the classic and V2
engines can evolve independently, ports the gaps the classic-engine
integration tests had been exercising, and lands the public V2 API
additions needed to close them.
- Splits `Tests/Opc.Ua.Subscriptions.Tests` into a classic
(`Opc.Ua.Subscriptions.Classic.Tests`) and a V2
(`Opc.Ua.Subscriptions.Tests`) project to shrink CI time and let the two
engines diverge cleanly.
- Adds the V2 public-surface gaps required by the test ports
(`Subscription.ServerId` on the class, `SetSubscriptionDurableAsync`,
`SendInitialValuesOnTransfer`, unified `OnSubscriptionStateChangedAsync`
handler callback, per-item `ConditionRefreshAsync`, fluent
`LoadSubscriptionsAsync(Stream, …)` and `Subscription.Snapshot()` /
`RestoreAsync()` for save/load + transfer).
- Lands handler-centric design (no `PublishingStopped` property handlers
maintain derived state); always-sequential per-subscription delivery
documented + tested.
- **Adds short and long haul stability tests for the V2 `ManagedSession`
+ subscription engine. Closes #3744** (see "Issue #3744 Haul tests"
below).
- **Migrates SubscriptionStateSnapshot / MonitoredItemStateSnapshot to
`[DataType]` source-generator codecs**.
- `SubscriptionDurableV2Tests.cs` 5 V2 ports of the classic durable test
patterns.
- `V2FollowUpCoverageTests.cs` handler state-change callback, fluent
stream-based `LoadSubscriptionsAsync`, `SendInitialValuesOnTransfer`,
snapshot edge cases (empty / `DataChangeFilter` round-trip / concurrent
mutation).
- `SubscriptionFailoverV2Tests.cs` forced channel-break with and without
`WithTransferSubscriptionsOnRecreate`.
- `MonitoredItemConditionRefreshLiveV2Tests.cs` ΓÇö live
`ConditionRefresh` against the reference server's event source; asserts
`RefreshStart` / `RefreshEnd` events flow through the handler.
## Fixes
- #3744 Haul tests (V2 ManagedSession + subscription engine)
`Tests/Opc.Ua.Sessions.Tests/ManagedSessionStabilityTest.cs` adds the
short/long haul coverage requested by
[#3744](https://github.com/OPCFoundation/UA-.NETStandard/issues/3744)
plus the bonus fault-injection variant:
| Test | Duration | Category | Purpose |
|---|---|---|---|
| `ShortHaulManagedSessionV2Async` | 2 minutes | `ManagedSessionHaul`
(`[Explicit]`) | Quick local sanity check of the V2 monotonicity
contract. |
| `LongHaulManagedSessionV2Async` | 90 minutes (configurable via
`TEST_DURATION_MINUTES`) | `ManagedSessionHaul` (`[Explicit]`) |
Long-running V2 stability + monotonicity. |
| `LongHaulManagedSessionWithFaultInjectionV2Async` | 90 minutes
(configurable) + fault every `FAULT_INJECTION_INTERVAL_SECONDS` (default
60s) | `ManagedSessionHaul` (`[Explicit]`) | **Bonus** ΓÇö force-closes
the subscriber transport channel periodically; verifies V2 manager
transfers/recreates the subscription and continues monotonic delivery
across reconnects. |
**Pattern.** A writer `ManagedSession` increments a `uint32` counter and
writes it into `Scalar_Static_Mass_UInt32_UInt32_00` every 250ms. A
subscriber `ManagedSession` runs a V2 subscription with a single
monitored item on the same node. `MonotonicCounterHandler` asserts each
received sample is *strictly greater than* the previous one. V2
`ISubscriptionNotificationHandler` per-subscription ordering guarantee.
Skipped values (sampling rate < write rate) are tolerated; duplicates
and reorderings are violations.
### Test project reorganization
Splits the integration- vs unit-test boundary along **project
boundaries**
and introduces a runtime-tier split for subscription tests so the
mainline
CI no longer drags in stress / durable suites.
**New projects:**
- `Opc.Ua.Stress.Tests` ΓÇö cross-area stress tier (designed to
absorb
session / channel / pub-sub stress in future). Seeded with the 6
subscription stress classes (`SubscriptionDepthTests`,
`SubscriptionBasicDepthTests`, `MonitoredItemDepthTests`,
`SubscriptionTransferDepthTests`, `SubscriptionPublishTooManyTests`,
`SubscriptionMultipleTests`). **Excluded from mainline CI; runs
nightly.**
- `Opc.Ua.Subscriptions.Durable.Tests` ΓÇö durable-subscription tier
(needs `DurableSubscriptionsEnabled` + storage-backed lifetime).
Receives `SubscriptionDurableTests` plus the migrated
`DurableSubscriptionTest` and `DurableSubscriptionTestDebug`.
**Excluded from mainline CI; runs nightly.**
- `Opc.Ua.Features.Tests` ΓÇö cross-feature integration tier.
Receives the
`[OneTimeSetUp]`-bootstraps-its-own-server integrations for AliasNames
(Part 17), Roles (Part 18), FileSystem (Part 5 §C / Part 20), and
NodeCache. Also absorbs the misplaced
`Tests/Opc.Ua.History.Tests/FileSystemTests.cs`.
**Client.Tests cleanup (~28 files moved):**
- `Opc.Ua.Sessions.Tests` (existing) gains 10 session integration files
plus the 4 session benchmark files inline (`LoadTest`,
`RequestHeaderTest`, `TraceableRequestHeaderTest`,
`SecurityPolicyBenchmarks`).
- `Opc.Ua.Subscriptions.Tests` (existing) gains 4 subscription
integration files plus `PooledNotificationBenchmarks` inline.
- `Opc.Ua.Client.ComplexTypes.Tests` (existing) gains all
`ComplexTypes/*` integration files. The Client.Tests copy of
`TypeSystemClientTest.cs` (a stale near-duplicate) is removed.
- Benchmarks **stay inline** as `[Test]` + BenchmarkDotNet dual-use; no
new benchmark project (per the approved plan).
**CI pipeline:**
- `.azurepipelines/test.yml` now filters
`TestCategory!=LongRunning&TestCategory!=Stress` on the mainline run.
- `-ExcludeFileName` now accepts a comma-separated list. The mainline
matrix excludes the 3 nightly-tier project files alongside the
existing `Opc.Ua.Aot.Tests.csproj`.
- `get-matrix.ps1` enhanced to support multi-pattern excludes.
`InternalsVisibleTo` extended on `Opc.Ua.Client` and `Opc.Ua.Server` to
grant the new test projects access. All affected projects build clean
(`0 Error`) for `net10.0`.
### Fix 8 skipped tests flagged as suspected bugs
Triage of every `[Ignore]` / `[Explicit]` test in `Tests/**` surfaced 8
entries labelled as suspected production bugs. After inspection:
- **1 real production bug** ΓÇö the
`CancellationTokenSource.CancelAsync`
polyfill for netstandard2.0 / netfx was running cancellation callbacks
inline on the caller's thread, deadlocking dispose paths
(`SubscriptionManager.DisposeAsync`, etc.) when a callback awaits on
the caller's `SynchronizationContext`. Fixed at the polyfill root by
hoisting `Cancel()` onto the ThreadPool via `Task.Run`, matching real
.NET 8+ semantics. Caveat (deferred `IsCancellationRequested`
transition) documented inline; all in-repo callers use
`await cts.CancelAsync()` so the deviation is invisible. Test
`DrainAsyncWaitsForInFlightPublishToCompleteAsync` un-ignored ΓÇö
verified passes on net48 (943 ms) and net10.0 (1 s).
- **2 flaky tests stabilized** ΓÇö both
`ValidateMetaDataUpdateTimeNonZeroIsSentPeriodically` (MQTT JSON &
UADP) now use `Stopwatch.GetTimestamp()` instead of `DateTime.Now`,
compute deviation against the **median** interval (not the configured
cadence, so a startup hiccup doesn't skew the run), and use a
proportional `max(interval / 4, 50 ms)` tolerance. `[Ignore]` removed,
`[Category("LongRunning")]` retained.
- **1 mis-labelled "bug"** ΓÇö
`UnorderedMessagesWouldBeLostForSequentialPublishingAsync` asserts the
*documented* lossy trade-off of strict sequential publishing.
`[Explicit]`
removed and renamed to
`OldMessagesAbandonedAfterRepublishTimeoutInSequentialModeAsync`; it's
now a CI-verified regression test for the WAI behavior.
- **4 false positives** ΓÇö `JsonEncoderTestsOld.cs` (16 kLOC) was
excluded from compilation via `<Compile Remove>` and never reached the
runner. The 4 `[Ignore("ProductionBugSuspected")]` markers inside were
orphaned source from a previous JsonEncoder API. Active coverage lives
in `JsonEncoderTests.cs` and `JsonValidationData` fixtures. Deleted
the orphan file and the now-redundant `<Compile Remove>` line.
* New certificate and secrete abstraction with certificate infrastructure and certificate/secret stores.
* leak testing for certificate resources to validate new ref counting in every test assembly
* Migration guide updated and documentation added for all
* Remove IDisposable from Nodestate and UserIdentity.
* UserCertificateTokenHandler now just points into certificate registry/stores, no dispose required
* Fix CA2000 warnings and cleanup of other diagnostics, increase warning levels in .editorconfig
- Add new managed session, wrapping session and providing connection management and failover handling
- Add new Subscription engine that can act as alternative to current engine, but is based on channels with worker tasks
- Add a fluent builder for managed session clients
- Replace NodeCache with LruNodeCache, rename ILruNodeCache and LruNodeCache to INodeCache and NodeCache
- Update migration guide and document new functionality.
Marc Schier