## Proposed changes
Reduces sync-over-async in non-obsolete server APIs, removes stale
`#region/#endregion` noise from the test suite, and fixes analyzer/test
fallout from merging the Part 11 Historical Access framework (#3797).
Follow-up review feedback is included: `FileSystemNodeManager` is now
based on `AsyncCustomNodeManager`.
### Sync-over-async reduction (~24 `GetAwaiter().GetResult()` sites)
**Server-side:**
- `TrustList`: async `OnCallAsync` handlers added; sync `OnCall`
handlers retained as compat shims so legacy `CustomNodeManager2`
subclasses that host the TrustList but do not implement
`ICallAsyncNodeManager` keep working through `MethodState.Call`.
- `GDS ApplicationsNodeManager`: `RequestAccessToken`,
`KeyCredentialStart/FinishRequest`, and `Revoke` moved to `OnCallAsync`.
- `IKeyCredentialRequestStore`: interface + in-memory implementation
converted to async; `FinishKeyCredentialRequestResult` record carries
the previous out-set. Tests in `Tests/Opc.Ua.Gds.Tests/` updated to the
new async API.
- `FileSystem`:
- `DirectoryObjectState` methods (`CreateDirectory` / `CreateFile` /
`Delete` / `MoveOrCopy`) use `OnCallAsync`.
- `FileSystemNodeManager` now derives from `AsyncCustomNodeManager` and
overrides async address-space/node-resolution paths
(`CreateAddressSpaceAsync`, `DeleteAddressSpaceAsync`,
`GetManagerHandleAsync`, `ValidateNodeAsync`) to avoid sync-over-async
in dynamic node validation.
- `FileSystemNodeManagerFactory` now supports async creation
(`IAsyncNodeManagerFactory`) while retaining sync factory compatibility.
- Reference server registration of the FileSystem node manager is
aligned to the async node manager list.
- `ConfigurationNodeManager` namespace lookup uses sync
`GetManagerHandle` to keep the remaining `GetResult` inside the
documented `SyncNodeManagerAdapter` bridge.
- `ServerBase`: new `OnServerStartingAsync`; `StartAsync` now awaits it.
- `StandardServer.CreateMasterNodeManagerAsync` added; sync wrapper kept
for backward compatibility.
- `IServerInternal.CloseSession` marked `[Obsolete]`
(`CloseSessionAsync` exists).
- `IMasterNodeManager.RemoveReferences` marked `[Obsolete]`; in-tree
sync callers remain with scoped `CS0618` pragmas + TODO.
**Stack:**
- `EncryptedSecret`: added `VerifyHeaderForEccAsync` / `DecryptAsync` /
`TryDecryptAsync`; `UserNameIdentityTokenHandler.DecryptAsync` awaits
ECC validation.
- `CertificatePasswordProvider` ctor: `GetResult` fallback replaced with
explicit `InvalidOperationException`.
### Code-style and post-merge cleanup
- Removed unused `#region`/`#endregion` directives across test files.
- Restored green build state after Part 11 merge fallout fixes
(production + analyzer + test cleanup from earlier commits in this PR).
### CI / validation notes
- This PR branch surfaced runtime regressions introduced by Part 11
after the build-breaker was fixed (outside scope of this
async/code-style cleanup).
- Follow-up feedback change validation for `FileSystemNodeManager`:
- `dotnet build Libraries/Opc.Ua.Server/Opc.Ua.Server.csproj -f net10.0
--no-restore` ✅
- `dotnet test Tests/Opc.Ua.Server.Tests/Opc.Ua.Server.Tests.csproj -f
net10.0 --filter FileSystemNodeIdTests` ✅
- `dotnet test Tests/Opc.Ua.History.Tests/Opc.Ua.History.Tests.csproj -f
net10.0 --filter FileSystemSmokeTests` ✅ (test skipped in environment)
## Related Issues
- None.
## Types of changes
- [ ] Bugfix (non-breaking change which fixes an issue)
- [x] Enhancement (non-breaking change which adds functionality)
- [x] Test enhancement (non-breaking change to increase test coverage)
- [ ] Breaking change (fix or feature that would cause existing
functionality to not work as expected, requires version increase of
Nuget packages)
- [ ] Documentation Update (if none of the other choices apply)
## Checklist
- [x] I have read the
[CONTRIBUTING](https://github.com/OPCFoundation/UA-.NETStandard/blob/master/CONTRIBUTING.md)
doc.
- [x] I have signed the
[CLA](https://opcfoundation.org/license/cla/ContributorLicenseAgreementv1.0.pdf).
- [x] I ran tests locally with my changes, all passed.
- [ ] I fixed all failing tests in the CI pipelines.
- [ ] I fixed all introduced issues with CodeQL and LGTM.
- [x] I have added tests that prove my fix is effective or that my
feature works and increased code coverage.
- [x] I have added necessary documentation (if appropriate).
- [x] Any dependent changes have been merged and published in downstream
modules.
## Proposed changes
Implements **OPC UA Part 11 (Historical Access)** end-to-end via a clean
**provider model** that lets servers back historizing variables with any
time-series storage engine. A reference-quality **in-memory engine**
ships in `Opc.Ua.Server` so getting started requires no extra packages.
The implementation replaces the legacy `HistoryArchive` /
`HistoryDataReader` / `HistoryFile` / `IHistoryDataSource` files
(removed from `Quickstarts.Servers/TestData/`) with a stack-level Part
11 surface.
### What's new
- **Server provider model** in `Libraries/Opc.Ua.Server/Historian/`:
- Umbrella `IHistorianProvider` + narrow capability interfaces
(`IHistorianDataProvider`, `IHistorianModifiedProvider`,
`IHistorianAtTimeProvider`, `IHistorianProcessedProvider`,
`IHistorianAnnotationProvider`, `IHistorianEventProvider`,
`IHistorianTransactionalProvider`).
- `HistorianDispatcher` — routes HistoryRead / HistoryUpdate (raw,
modified, at-time, processed, events, annotations) including
event-`WhereClause` evaluation via the framework's `FilterEvaluator`,
audit-event reporting, and continuation-point lifecycle.
- `HistorianProviderRegistry` with Node → Namespace → Default
precedence; surfaced via `IHistorianRegistryProvider` on
`ServerInternalData`.
- Fluent `HistorianBuilder`
(`server.UseHistorian().UseInMemory().Historize(...).RegisterAsDefault()`).
- Lazy `HistoricalDataConfigurationType` companion installer
(`OnPopulateBrowser`-attached).
- `ServerSystemContext` now exposes `IServerInternal Server { get; }` so
infrastructure code stops relying on the per-NM `SystemHandle`.
- **In-memory reference engine** (`InMemoryHistorianProvider`) — raw,
modified, processed via framework fallback, at-time via framework
fallback, annotations, events, transactional batches.
- **Client surface** in `Libraries/Opc.Ua.Client/Historian/`:
- `HistoryClient` with `IAsyncEnumerable<DataValue>`
raw/modified/at-time/processed/annotation reads (transparent
continuation-point handling and `try/finally`-based release on iterator
abandonment).
- `session.Historian()` extension.
- Capability discovery (`GetServerCapabilitiesAsync`,
`GetConfigurationAsync`).
- **Node-manager wiring** through both `AsyncCustomNodeManager` and
`CustomNodeManager2` (sync-via-dispatcher).
- **Capability rollup** — `DiagnosticsNodeManager` populates the
server-wide `HistoryServerCapabilities` as the union of registered
providers' `GetCapabilitiesAsync(NodeId.Null, ...)` (runs whether the
node was loaded from the predefined nodeset or freshly created; fully
async).
- **Audit-event reporting** for HistoryUpdate (gated on
at-least-one-success):
`AuditHistoryValueUpdateEventType`,
`AuditHistoryAnnotationUpdateEventType`,
`AuditHistoryRawModifyDeleteEventType`,
`AuditHistoryAtTimeDeleteEventType`, `AuditHistoryEventUpdateEventType`,
`AuditHistoryEventDeleteEventType`.
- **ReferenceServer + TestData** historize sample variables through the
new pipeline (replaces the deleted legacy `HistoryArchive`).
- **Comprehensive developer documentation** in
`Docs/HistoricalAccess.md` (~657 lines): server-developer guide,
provider-author guide, client-developer guide, capability discovery,
auditing, limitations/roadmap.
### Tests
| Suite | Files | Tests |
| --- | --- | --- |
| Server unit (Opc.Ua.Server.Tests/Historian) | dispatcher,
event-dispatcher, registry, in-memory provider, transactional provider,
concurrency, coverage, event-filter target | **34** passing |
| Client integration (Opc.Ua.Client.Tests/Historian) |
`HistoryClientIntegrationTests` over the live `ReferenceServer` via
`ServerFixture` | **4** passing |
| AOT (Opc.Ua.Aot.Tests/HistoryAotTests) | positive assertions against
historized `Scalar_Static_Int32` (read raw, read processed/Average) |
**2** passing |
### Local validation
- `dotnet build UA.slnx -c Release` → **0 errors**.
- All historian / client integration / AOT history tests **green**.
### Hardening applied post-internal-review
- `DiagnosticsNodeManager.RollUpHistorianCapabilitiesAsync` — true async
(no more `.GetAwaiter().GetResult()` on the startup path).
- `HistoryClient` raw/modified/details readers — `try/finally` releases
the in-flight continuation point on `break`/exception/cancellation; also
detects malformed-server empty-page loops.
- `ReportAudit*` helpers gated on `HasAnyGood(...)` — audit events do
not fire when every per-value op failed.
- `ServerSystemContext` ctors throw
`ArgumentNullException(nameof(server))` at the boundary.
- `HistorianEventFilterTarget.IsTypeOf` logs a one-shot warning when
`IFilterContext.TypeTree` is null (degrades safely instead of silently).
- `InMemoryHistorianProvider.ReadEventsAsync` snapshots under lock,
filters outside (cuts lock-hold time).
- `TryRestoreContinuation` rejects cross-wired continuation points
(different `NodeId`).
- Processed-read framework fallback capped at 100 000 buffered outputs
(`BadTooManyOperations` when exceeded).
- ReferenceServer / TestData seeding is async-awaited /
`Task.Run`-bridged to escape any captured `SynchronizationContext`.
## Related Issues
- Fixes #
## Types of changes
- [x] Bugfix (non-breaking change which fixes an issue)
- [x] Enhancement (non-breaking change which adds functionality)
- [x] Test enhancement (non-breaking change to increase test coverage)
- [ ] Breaking change
- [x] Documentation Update
> The deletion of legacy
`Applications/Quickstarts.Servers/TestData/HistoryArchive*` is a
refactor of sample code only; the public stack surface is purely
additive.
## Checklist
- [x] I have read the
[CONTRIBUTING](https://github.com/OPCFoundation/UA-.NETStandard/blob/master/CONTRIBUTING.md)
doc.
- [x] I have signed the
[CLA](https://opcfoundation.org/license/cla/ContributorLicenseAgreementv1.0.pdf).
- [x] I ran tests locally with my changes, all passed.
- [ ] I fixed all failing tests in the CI pipelines.
- [ ] I fixed all introduced issues with CodeQL and LGTM.
- [x] I have added tests that prove my fix is effective or that my
feature works and increased code coverage.
- [x] I have added necessary documentation (`Docs/HistoricalAccess.md`).
- [x] Any dependent changes have been merged and published in downstream
modules.
## Further comments
The provider model is intentionally minimal and orthogonal — providers
opt into specific Part 11 features by implementing one or more of the
narrow capability interfaces, and the dispatcher type-tests the concrete
provider at runtime. This keeps the bundled `InMemoryHistorianProvider`
simple while making it trivial for vendors to plug in their own
time-series database.
A few items remain explicitly deferred (documented in
`Docs/HistoricalAccess.md` *Limitations and roadmap*):
`HistoricalEventConfigurationType` auto-install for event notifiers,
audit-event `OldValues` fidelity (would require read-before-write across
update sites), true streaming processed-read continuation (the framework
fallback is bounded by the 100 k cap; native
`IHistorianProcessedProvider` providers already get arbitrary paging).
These are on-demand items, not gaps in the mandatory Part 11 surface.
Drive the solution to zero warnings / zero errors with analyzers on,
promote the consistently-fixed rules to error, and lock in coverage
on the only line of new logic.
* Use Interfaces Introduced with 1.5.378
Refactor to use interfaces for node managers and server
Replaced concrete types with interfaces (e.g., IMasterNodeManager, ICoreNodeManager, IDiagnosticsNodeManager, IConfigurationNodeManager, IServerBase) across method signatures, properties, and internal structures to improve abstraction and flexibility.
* Refactor CoreNodeManager to be Based on CustomNodeManager2
* Add Test
* Add INodeManager3 with role permission validation
Introduce INodeManager3 interface extending INodeManager2, adding synchronous role permission validation methods. Update all node manager interfaces and classes to use INodeManager3. Extend IAsyncNodeManager with async permission validation methods and update adapters for sync/async bridging. Deprecate FindNodeInAddressSpace in favor of new async FindNodeInAddressSpaceAsync. Refactor MonitoredNode2 to use thread-safe collections and locking for monitored items. Enhance event reporting with security and permission checks. Update constructors and documentation to reflect new interfaces and best practices.
* Implement AsyncCustomNodeManager
* fix comment
* fix
* Add tests
* fix
* Implement better locking strategy
* fix
* Add more tests
* Add tests
* Add tests
* Add Tests
* cleanup
* cleanup
* Add tests that verifies for AnalogItemState the instrument range is checked brefore writing
* only assign new NodeID in default factory if NodeId isNull
* Run all tests also with sampling groups
* Add Docs
* cleanup
* Add chaos test
* fix test
This pull request modernizes the OPC UA .NET codebase and tests, removes .NET Standard 2.0 support from certificate/security code, and updates test code to use C# 12 and .NET 8+ features for clarity and maintainability.
- Certificate and BouncyCastle interop files (e.g., CertificateBuilder.cs, X509Extensions.cs, X509SignatureFactory.cs) are refactored to drop NETSTANDARD2_0 support and use modern .NET APIs and conditional compilation.
- Test code across the codebase is updated to use default, strongly-typed Parse methods, collection expressions, and improved async/await patterns.
- Exception handling and assertions in tests are modernized, and test method naming is made consistent with Async suffixes.
- The project and build files are updated to clarify Roslynator analyzer usage and remove obsolete netstandard tags.
- General code and test cleanup includes improved null safety, type safety, and removal of deprecated or unused code.
This change adds a **new Opc.Ua.Types** nuget that contains core types that do not rely on generated code. Why the name? Because almost all code that was in the Types subfolder is part of it, and because we do not want to change the name of the Opc.Ua.Core nuget/assembly because code relies on it. Any other name like base or bootstrap felt out of place due to the current structure already defining the name "types". Key design is to depend on only a small set of libraries with limited transitive dependencies, that includes hashcode, logging.abstraction, and for non standard20 builds System.Text.Json (needed for localizedText mul parsing). Also, key is to support .netstd 2.0 to support source generators and to allow removal of EEC_SUPPORT defines by removing std2.0 from core and all libraries.
The changes are mostly restructuring, and thus small but contain some key changes:
- **Status code** struct now comes with a Symbol field, which is used to carry symbols in case the code is not generated. Currently (until generated) the status code struct must be manually created with a symbol or the ToSymbolicId extension must be called in the core project. Future will generate Status code constants just like NodeId that contain the symbol which also removes the reflection-based lookup. Several tests needed to be adjusted as they checked the status code symbol strings instead of the code.
- **Core identifiers** are copied as they were needed for code to compile, that includes attributes, a subset of status codes and node identifiers. These will never change so no need to generate them.
- The types folder now contains **encoders**, except for json which is still in core. Once the json encoder is ported to system.text.json it will also be included and Newtonsoft.Json dropped as dependency (-> #3329).
- Since types relies on **IOperationContext** and **ISystemContext**, and these export IUserIdentity which relies on crypto, these were split and extended in core with ISessionOperationContext and ISessionSystemContext, which mean changes to ServerSystemContext and introduction of SessionOperationContext and SessionSystemContext classes that extend OperationContext and SystemContext. Some runtime checks in the server are therefore needed to get at the session and auth info, however, those are anyway optional fields and are not on the critical paths, and thus a type check is in order (and was done in the past already, but against OperationContext class).
- **Manifest resources** are now split between Core (nodeset zip, some generated resoures) and Types (built in bsd/xsds). This needs to be revisited later if the bsd/xsd need to be regenerated during type generation. Note that the embedded resource names changed as a result. Since these are only used internally and do not constitute public API this feels reasonable vs duplication of resources in 2 assemblies.
- Reflection however now needs to load not just the built in **encodeables** from Opc.Ua.Types assembly, but also the generated encodeables from Opc.Ua.Core assembly. For this a new helper Utils method was added to get the Core assembly when linked against Opc.Ua.Core otherwise null.
- Whatever utils methods needed to be split out into the new Opc.Ua.Types assembly, they are now in **CoreUtils** static class in Opc.Ua.Types, and Utils.xxxx forwards to them to ensure minimal changes. Later we would want to obsolete them in favor of CoreUtils, although it might make sense to split them again into domain specific utilities, such as networking, files, etc