Files
lmxopcua/docs/v2/lmx-followups.md
Joseph Doherty bf329b05d8 Phase 3 PR 35 — IHistoryProvider gains ReadAtTimeAsync + ReadEventsAsync; GalaxyProxyDriver implements both. Extends Core.Abstractions.IHistoryProvider with two new methods that round out the OPC UA Part 11 HistoryRead surface (HistoryReadAtTime + HistoryReadEvents are the last two modes not covered by the PR 19-era ReadRawAsync + ReadProcessedAsync) and wires GalaxyProxyDriver to call the existing PR-10/PR-11 IPC contracts the Host already implements.
Interface additions use C# default interface implementations that throw NotSupportedException — existing IHistoryProvider implementations keep compiling, only drivers whose backend carries the relevant capability override. This matches the 'capabilities are optional per driver' design already used by IHistoryProvider.ReadProcessedAsync's docs (Modbus / OPC UA Client drivers never had an event historian and the default-throw path lets callers see BadHistoryOperationUnsupported naturally). New HistoricalEvent record models one historian row (EventId, SourceName, EventTimeUtc + ReceivedTimeUtc — process vs historian-persist timestamps, Message, Severity mapped to OPC UA's 1-1000 range); HistoricalEventsResult pairs the event list with a continuation-point token for future batching. Both live in Core.Abstractions so downstream (Proxy, Host, Server) reference a single domain shape — no Shared-contract leak into the driver-facing interface.
GalaxyProxyDriver.ReadAtTimeAsync maps the domain DateTime[] to Unix-ms longs, calls CallAsync on the existing MessageKind.HistoryReadAtTimeRequest, and trusts the Host's one-sample-per-requested-timestamp contract (the Host pads with bad-quality snapshots for timestamps it can't interpolate; re-aligning on the Proxy side would duplicate the Host's interpolation policy logic). ReadEventsAsync does the same for HistoryReadEventsRequest; ToHistoricalEvent translates GalaxyHistoricalEvent (MessagePack-annotated, Unix-ms) to the domain record, explicitly tagging DateTimeKind.Utc on both timestamp fields so downstream serializers (JSON, OPC UA types) don't apply an unexpected local-time offset.
Tests — HistoricalEventMappingTests (3 new Proxy.Tests unit cases): every field maps correctly from wire to domain; null SourceName and null DisplayText preserve through the mapping (system events without a source come out with null so callers can distinguish them from alarm events); both timestamps come out as DateTimeKind.Utc (regression guard against a future refactor using DateTime.FromFileTimeUtc or similar that defaults to Unspecified). Driver.Galaxy.Proxy.Tests Unit suite: 17 pass / 0 fail (14 prior + 3 new). Full solution build clean, 0 errors.
Scope exclusions — DriverNodeManager HistoryRead service-handler wiring (on the OPC UA Server side, where HistoryReadAtTime and HistoryReadEvents service requests land) and the full-loop integration test (OPC UA client → server → IPC → Host → HistorianDataSource → back) are deferred to a focused follow-up PR. The capability surface is the load-bearing change; wiring the service handlers is mechanical in comparison and worth its own PR for reviewability. docs/v2/lmx-followups.md #1 updated with the split.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
2026-04-18 16:08:27 -04:00

7.1 KiB

LMX Galaxy bridge — remaining follow-ups

State after PR 19: the Galaxy driver is functionally at v1 parity through the IDriver abstraction; the OPC UA server runs with LDAP-authenticated Basic256Sha256 endpoints and alarms are observable through AlarmConditionState.ReportEvent. The items below are what remains LMX- specific before the stack can fully replace the v1 deployment, in rough priority order.

1. Proxy-side IHistoryProvider for ReadAtTime / ReadEvents

Status: Capability surface complete (PR 35). OPC UA HistoryRead service-handler wiring in DriverNodeManager remains as the next step; integration-test still pending.

PR 35 extended IHistoryProvider with ReadAtTimeAsync + ReadEventsAsync (default throwing implementations so existing impls keep compiling), added the HistoricalEvent + HistoricalEventsResult records to Core.Abstractions, and implemented both methods in GalaxyProxyDriver on top of the PR 10 / PR 11 IPC messages. Wire-to-domain mapping (ToHistoricalEvent) is unit-tested for field fidelity, null-preservation, and DateTimeKind.Utc.

Remaining:

  • DriverNodeManager wires the new capability methods onto HistoryRead AtTime + Events service handlers.
  • Integration test: OPC UA client calls HistoryReadAtTime / HistoryReadEvents, value flows through IPC to the Host's HistorianDataSource, back to the client.

2. Write-gating by role — DONE (PR 26)

Landed in PR 26. WriteAuthzPolicy in Server/Security/ maps SecurityClassification → required role (FreeAccess → no role required, Operate/SecuredWriteWriteOperate, TuneWriteTune, Configure/VerifiedWriteWriteConfigure, ViewOnly → deny regardless). DriverNodeManager caches the classification per variable during discovery and checks the session's roles (via IRoleBearer) in OnWriteValue before calling IWritable.WriteAsync. Roles do not cascade — a session with WriteOperate can't write a Tune attribute unless it also carries WriteTune.

See feedback_acl_at_server_layer.md in memory for the architectural directive that authz stays at the server layer and never delegates to driver-specific auth.

3. Admin UI client-cert trust management — DONE (PR 28)

PR 28 shipped /certificates in the Admin UI. CertTrustService reads the OPC UA server's PKI store root (OpcUaServerOptions.PkiStoreRoot — default %ProgramData%\OtOpcUa\pki) and lists rejected + trusted certs by parsing the .der files directly, so it has no Opc.Ua dependency and runs on any Admin host that can reach the shared PKI directory.

Operator actions: Trust (moves rejected/certs/*.dertrusted/certs/*.der), Delete rejected, Revoke trust. The OPC UA stack re-reads the trusted store on each new client handshake, so no explicit reload signal is needed — operators retry the rejected client's connection after trusting.

Deferred: flipping AutoAcceptUntrustedClientCertificates to false as the deployment default. That's a production-hardening config change, not a code gap — the Admin UI is now ready to be the trust gate.

4. Live-LDAP integration test — DONE (PR 31)

PR 31 shipped Server.Tests/LdapUserAuthenticatorLiveTests.cs — 6 live-bind tests against the dev GLAuth instance at localhost:3893, skipped cleanly when the port is unreachable. Covers: valid bind, wrong password, unknown user, empty credentials, single-group → WriteOperate mapping, multi-group admin user surfacing all mapped roles.

Also added UserNameAttribute to LdapOptions (default uid for RFC 2307 compat) so Active Directory deployments can configure sAMAccountName / userPrincipalName without code changes. LdapUserAuthenticatorAdCompatTests (5 unit guards) pins the AD-shape DN parsing + filter escape behaviors. See docs/security.md §"Active Directory configuration" for the AD appsettings snippet.

Deferred: asserting session.Identity end-to-end on the server side (i.e. drive a full OPC UA session with username/password, then read an IHostConnectivityProbe-style "whoami" node to verify the role surfaced). That needs a test-only address-space node and is a separate PR.

5. Full Galaxy live-service smoke test against the merged v2 stack

Status: Individual pieces have live smoke tests (PR 5 MXAccess, PR 13 probe manager, PR 14 alarm tracker), but the full loop — OPC UA client → OtOpcUaServerGalaxyProxyDriver (in-process) → named-pipe to Galaxy.Host subprocess → live MXAccess runtime → real Galaxy objects — has no single end-to-end smoke test.

To do:

  • Test that spawns the full topology, discovers a deployed Galaxy object, subscribes to one of its attributes, writes a value back, and asserts the write round-tripped through MXAccess. Skip when ArchestrA isn't running.

6. Second driver instance on the same server — DONE (PR 32)

Server.Tests/MultipleDriverInstancesIntegrationTests.cs registers two drivers with distinct DriverInstanceIds on one DriverHost, spins up the full OPC UA server, and asserts three behaviors: (1) each driver's namespace URI (urn:OtOpcUa:{id}) resolves to a distinct index in the client's NamespaceUris, (2) browsing one subtree returns that driver's folder and does NOT leak the other driver's folder, (3) reads route to the correct driver — the alpha instance returns 42 while beta returns 99, so a misroute would surface at the assertion layer.

Deferred: the alarm-event multi-driver parity case (two drivers each raising a GalaxyAlarmEvent, assert each condition lands on its owning instance's condition node). Alarm tracking already has its own integration test (AlarmSubscription*); the multi-driver alarm case would need a stub IAlarmSource that's worth its own focused PR.

7. Host-status per-AppEngine granularity → Admin UI dashboard — DONE (PRs 33 + 34)

PR 33 landed the data layer: DriverHostStatus entity + migration with composite key (NodeId, DriverInstanceId, HostName) and two query-supporting indexes (per-cluster drill-down on NodeId, stale-row detection on LastSeenUtc).

PR 34 wired the publisher + consumer. HostStatusPublisher is a BackgroundService in the Server process that walks every registered IHostConnectivityProbe-capable driver every 10s, calls GetHostStatuses(), and upserts rows (LastSeenUtc advances each tick; State + StateChangedUtc update on transitions). Admin UI /hosts page groups by cluster, shows four summary cards (Hosts / Running / Stale / Faulted), and flags rows whose LastSeenUtc is older than 30s as Stale so operators see crashed Servers without waiting for a state change.

Deferred as follow-ups:

  • Event-driven push (subscribe to OnHostStatusChanged per driver for sub-heartbeat latency). Adds DriverHost lifecycle-event plumbing; 10s polling is fine for operator-scale use.
  • Failure-count column — needs the publisher to track a transition history per host, not just current-state.
  • SignalR fan-out to the Admin page (currently the page polls the DB, not a hub). The DB-polled version is fine at current cadence but a hub push would eliminate the 10s race where a new row sits in the DB before the Admin page notices.