romanettandClaude Opus 5
30ed2390a8
## What
`INodeManagerBuilder.Import(UANodeSet, INodeSetImportFactoryProvider?)`
lets a source-generated (or hand-written fluent) node manager overlay a
NodeSet2 document that is only known at runtime onto the model it was
generated from.
Every document imported during one `Configure` pass forms a single batch
that is linked **exactly once** after the pass. A node may therefore
declare a `ParentNodeId` that lives in another document of the batch, or
a node the manager already owns — which is what makes an overlay
possible. Imported nodes resolve through
`Node(...)`/`NodeFromTypeId(...)` immediately, so they can be wired in
the same pass; they are registered with the manager when
`CompleteConfigureAsync` runs.
### Public surface
- **+1 method**: `INodeManagerBuilder.Import(UANodeSet nodeSet,
INodeSetImportFactoryProvider? factoryProvider = null)`.
- **+3 contracts** in `Opc.Ua.Server.Nodes`:
`INodeSetImportFactoryProvider`, `INodeSetImportFactory`,
`NodeSetImportDiscriminator` (TypeDefinition / MethodDeclaration /
NodeId).
- In `Opc.Ua.Export`: a public `UANodeSet.Import` overload taking a
`NodeSetImportStateFactory`, and a public batch
`LinkParentChildRelationships(context, nodes,
NodeSetImportLinkOptions)`. These replace what would otherwise have been
an `InternalsVisibleTo("Opc.Ua.Server")` on `Opc.Ua.Types`.
- `NodeState.IsExplicitlyDefinedChild(context, child)` and `protected
DetachExplicitlyDefinedChild(child)`, used to tell a generated slot
apart from an ordinary child.
### Typed states, no reflection
The generator emits `{Model}NodeSetImportFactoryProvider` — one factory
per model type/declaration, each calling a concrete constructor for an
*empty* state — and makes the generated node manager implement
`INodeSetImportFactoryProvider` by delegating to it. So the builder
resolves the provider from the manager (`NodeManager as
INodeSetImportFactoryProvider`); `Import` also accepts one directly, and
the generated manager exposes `partial void
AddNodeSetImportFactories(List<INodeSetImportFactory>)` for dependency
models. An imported node of a generated type materializes as its
generated `*State` subclass with no type lookup, which keeps the path
NativeAOT-safe.
Because the factories create empty states, an imported instance carries
exactly the children its document declares.
### Reconciliation
When an imported child lands in a slot the generated parent declares
(same BrowseName), it replaces the generated placeholder: the displaced
node and every descendant the document does not carry over are removed
from the manager, and references to them are retargeted at the
replacement. Replacing a node the same `Configure` pass already wired is
rejected with `BadInvalidState` rather than silently dropping the
wiring, and sealing a builder with an unregistered import batch is
rejected too.
### Also
- `RuntimeNodeSetNodeManager` now uses the same importer: its documents
are one batch, so a node may declare a parent in another document of the
group regardless of parse order, and duplicate NodeIds across documents
are detected while parsing.
- Linking resolves an imported child's reference type from its own
inverse reference (previously always `HasComponent`/`HasProperty`).
- Method import keeps the document's `UserExecutable`; it previously
copied `Executable` into it. View import keeps `EventNotifier`.
## Tests
- `NodeSetImporterTests` (15) — discriminator selection, generic
fallbacks, field/value/reference fidelity against a generic import,
cross-document linking, typed replacement of inherited and argument
slots, deferred linking preserving an application `Handle`, duplicate
NodeIds, factory misuse.
- `NodeSetImportBuilderTests` (15) — staging and lookup before
registration, batch linking, attaching to an existing node, provider
resolution, placeholder replacement with reference retargeting,
configured-placeholder rejection, seal/completion guards.
- `NodeSetImportIntegrationTests` (5) — a generated `[NodeManager]`
overlaying its own model on a running server: typed states through the
generated provider, cross-document linking, placeholder replacement, and
browse through a session.
- `NodeManagerGeneratorTests` (+4) — the emitted provider and the
manager's delegation, including that no factory uses
`Activator.CreateInstance`/reflection.
- `NodeSetAotTests` (+1) — the public state-factory import under
NativeAOT.
Full `Opc.Ua.Server.Tests` (4946), `Opc.Ua.SourceGeneration.Core.Tests`
(3821), `Opc.Ua.SourceGeneration.Tests` (165) and `Opc.Ua.Types.Tests`
pass locally on net10.0.
🤖 Generated with [Claude Code](https://claude.com/claude-code)
---------
Co-authored-by: Claude Opus 5 <noreply@anthropic.com>
OPC UA .NET Standard Stack
🆕 This is version 2.0 of the OPC UA .NET Standard Stack (current
master).Looking for the supported 1.x release? It lives on the
master378branch (last release:1.5.378). All new feature work happens here onmaster;master378continues to receive security and critical-bug fixes for the 1.x line.
The official OPC Foundation reference implementation of OPC UA for .NET — a certified, cross-platform stack with client, server, PubSub, GDS, complex types, and source-generated tooling. Used in production across industrial control, manufacturing, energy, and IoT systems.
📦 What it is
- A full-stack OPC UA implementation — Core / Client / Server / PubSub / GDS / LDS / Complex Types / Device Integration / Positioning libraries built on .NET, with UA-TCP and HTTPS transports.
- Cross-platform — runs on .NET 10, .NET 9, .NET 8 (LTS), .NET Framework 4.8, and .NET Standard 2.1; ships Native-AOT-friendly assemblies.
- Certified for compliance — the reference server has been certified through an OPC Foundation Certification Test Lab and is continuously verified against the latest Compliance Test Tool (CTT).
- Companion-spec coverage — Part 9 (Alarms & Conditions), Part 11 (Historical Access), Part 13 (Aggregates), Part 16 (State Machines), Part 17 (Alias Names), Part 18 (Role Management), Part 20 (File Transfer), Part 100 (Device Integration), Parts 210/211 (Relative Spatial Location and Global Positioning), OPC-10030 (ISA-95 Common Model) with OPC-10031-4 Job Control V1/V2, OPC 30270 / OPC UA for Asset Administration Shell V2 and V3, OPC 10100-1 (WoT Connectivity), OPC 40001-1 (Industrial Automation), OPC 40010-1 (Robotics).
- Modern developer surface — first-class
Microsoft.Extensions.DependencyInjectionhosting (services.AddOpcUa()), fluent server + client builders, source-generated NodeManagers and DataTypes, and an MCP server so LLMs / Copilot can drive an OPC UA client.
For the full feature breakdown see OPC UA Profiles and Facets and the What's New in 2.0 tour.
🚀 Getting started
You need the .NET 10 SDK to build the repo. From the repository root:
dotnet restore UA.slnx
dotnet build UA.slnx
For the supported target frameworks and platform notes see
the Developer Guide. The official NuGet packages
are published to nuget.org under the OPCFoundation.NetStandard
prefix — the meta package
OPCFoundation.NetStandard.Opc.Ua
pulls in everything, or reference individual packages directly, e.g.
OPCFoundation.NetStandard.Opc.Ua.Client for clients or
OPCFoundation.NetStandard.Opc.Ua.Server for servers. Preview builds from
every successful master build are available from the
GitHub Packages NuGet feed.
Official public 2.0 preview releases are also on nuget.org. Enable prerelease
packages and use 2.0.0-preview.* to float to the latest published
2.0.0-preview.N release.
Samples
The stack also includes a large collection of platform-independent sample applications that turn its core services and companion models into runnable client/server workflows. More applications, including platform-specific examples, are available in the companion OPC UA .NET Samples repository.
Developer tools
- OPC UA MCP Server — installable .NET tool and container that exposes OPC UA client operations as MCP tools for LLMs and Copilot. The tools also ship as libraries (
…Opc.Ua.Mcp.Core,.PubSub,.Diagnostics,.PubSub.Diagnostics) so an application can embed them next to its own MCP tools.
🔧 Migrating from 1.5.378 to 2.0
The 2.0 release introduces breaking API changes, and comes with a full prescriptive migration guide that links to per-area documentation for the migration sub-topics.
Most of the mechanical migration work is automated:
OPCFoundation.NetStandard.Opc.Ua.MigrationAnalyzerNuGet — install it in your project to get 26 analyzer rules throughUA0030(excludingUA0013,UA0016,UA0017, and the shim-onlyUA0029) plus one-click code fixes for the patterns in the guide. Setup steps are in the package's NugetREADME.md.- Migration agent skill — the
opcua-v20-migrationskill walks Copilot / Claude / any coding agent through installing the NuGet, runningdotnet format analyzersto apply auto-fixes, and handling the small residual manual patterns. The skill knows which sub-doc to load for each symptom so it stays context-efficient.
Copilot CLI discovers the skill automatically inside a clone. To install it for use in any repository:
copilot plugin marketplace add OPCFoundation/UA-.NETStandard
copilot plugin install opcua-v20-migration@opcua-dotnet
If you are still on 1.x and not ready to upgrade, stay on the
master378
branch — it continues to receive security and critical-bug fixes.
🤝 Contributing and license
Community contributions are welcome. Fork the repository, make your changes on a branch, and open a pull request; see CONTRIBUTING.md for the contribution workflow.
Contributors must sign the OPC Foundation Contributor License Agreement (CLA). The CLA "I AGREE" gate is presented automatically on your first PR.
The project is licensed under the OPC Foundation MIT License. Report security vulnerabilities via the process documented in SECURITY.md.
📚 Further reading
- Documentation index — every per-feature doc with a one-line description.
- What's New in 2.0 — narrative tour of the 1.5.378 → 2.0 changes grouped by theme and layer.
- OPC UA Profiles and Facets — facets / transports / security policies the stack implements.
- Migration Guide — prescriptive
per-version migration reference (links to
docs/migrate/2.0.x/). - OPC UA Online Reference — the official OPC 10000 series specification index.
- Preview Nuget package feed —
prerelease builds from every successful
masterbuild.