OPCFoundation.NetStandard.Opc.Ua.XRegistry.Server

Opc.Ua.XRegistry.Server

The generic server-side xRegistry registry node managers for OPC UA. They serve a structurally addressed registry with an independent content fast path.

XRegistryRegistrationNodeManager, XRegistryFastPathNodeManager, and XRegistryFederationNodeManager derive from AsyncCustomNodeManager. Host them through IAsyncNodeManagerFactory; directly constructed managers use the same awaited lifecycle. Custom subclasses override LoadPredefinedNodesAsync, CreateAddressSpaceAsync, and SessionClosingAsync, awaiting their base implementations. Await DeleteAddressSpaceAsync before disposal to drain active operations and release handles.

The managers provide:

• Fast path — publishes registered resources under an Opaque NodeId whose Identifier is the raw content-id bytes, so a consumer resolves a resource in a single Read.
• Registration — the model's own lifecycle: CreateGroup / GetOrCreateGroup on the registry root, CreateResource / GetOrCreateResource on a group, and — because ResourceType is a FileType — the document is transferred with the inherited Open / Read / Write / Close. Xid remains the structural registry-relative Resource or Version path. Only a successful Close with accepted, byte-different staged content updates Version Epoch/ModifiedAt; it computes a separate content key (via IResourceContentIdProvider) and publishes or reuses the reference-counted Opaque fast-path node. Empty, rejected, clean, and byte-identical closes are side-effect free, and each Version permits one writer. Delete(ExpectedEpoch) gives optimistic concurrency on removal.
• Federation — publishes a proxy for a resource hosted by a remote registry as a real ResourceType instance carrying an ExternalReference and ResourceUrl while retaining structural ResourceId, VersionId, and Xid.
• Events — optionally emits the xRegistry 0.5.0 native OPC UA event hierarchy for successful registry interactions and projection reconciliation. Event support is disabled by default and requires an absolute EventSourceUrl; generated concrete EventState types are reported through the Server/registry/group/resource notifier chain.

Version events use the corresponding version file as SourceNode; resource events use the committed default-version file. Deleted events retain their former source identity and are reported through the nearest surviving notifier. Enabling events emits every mandatory event for each supported mutation; whole-registry creation/deletion events remain recommendations.

Version Labels, Epoch, CreatedAt, and ModifiedAt are independent per Version. Resource Meta uses synchronized MetaLabels, MetaEpoch, MetaCreatedAt, and MetaModifiedAt; Version changes do not mutate Resource Meta unless Versions or default-Version state also change.

Existing projection strategies and the original six-parameter XRegistryProjectionContext constructor remain compatible with events disabled. Event-enabled projections provide one atomic generation through IXRegistryProjectionGenerationProvider; version-aware projections opt into IXRegistryVersionedProjectionStrategy.

Document bytes live behind an injectable IXRegistryResourceStore; an in-process and a file-backed implementation ship with the package. Registry writes always require a SignAndEncrypt secure channel.

A concrete registry (for example a schema registry) supplies an IResourceContentIdProvider and its own companion namespace/NodeSet.

options.EventsEnabled = true;
options.EventSourceUrl = "https://registry.example.com";
options.GroupsAttributeName = "groups";
options.ResourcesAttributeName = "resources";
options.ResourceDocumentAttributeName = "schema";