Joseph Doherty
2ee84af1c0
Phase 0 of the ClusterClient→gRPC migration
(docs/plans/2026-07-22-clusterclient-to-grpc-plan.md). Standalone hardening: it
closes a gap that exists today and is a precondition for moving command/control
onto gRPC in later phases.
T0.1 — delete the ManagementActor ClusterClientReceptionist registration.
It was built for an out-of-cluster CLI that was never written: the shipped CLI
speaks HTTP Basic to /management, which asks the actor in-process through
ManagementActorHolder. Nothing in the repo ever sent to /user/management. The
actor still runs there; only the cross-boundary advertisement is gone. Six
documents claimed the CLI used ClusterClient — including the CLI's own README
"Architecture Notes" — and are corrected here rather than left to rot.
T0.2 — record, do not port, the dead integration-routing path.
IntegrationCallRequest is unwired at BOTH ends: RouteIntegrationCallAsync has
zero callers anywhere, and RegisterLocalHandler(Integration, …) appears only in
a test, so production always answers "Integration handler not available". It is
excluded from the gRPC contract (28 of 29 commands migrate) rather than
enshrined on an additive-only wire format, and deleting it during a
transport migration would mix a behavioural change into a change whose whole
value is that behaviour is identical. See
docs/known-issues/2026-07-22-integration-call-routing-is-dead-code.md.
T0.3 — preshared-key authentication on SiteStreamService.
The service shipped with no auth at all: plaintext h2c, no interceptor, so
anything that could reach a site node's :8083 could open a live data stream or
read audit rows back via PullAuditEvents/PullSiteCalls. ControlPlaneAuthInterceptor
now gates /sitestream.SiteStreamService/ — modeled on LocalDbSyncAuthInterceptor
(constant-time compare, fail-closed, PermissionDenied) but gating a SET of
service prefixes so phases 1A/1B add services rather than interceptors. LocalDb
sync keeps its own separate key: it authenticates the pair partner, not central,
and collapsing the two would make a site's central-facing key also admit writes
into its database.
Keys are per site (SB-GRPC-PSK-<siteId>), never fleet-wide, so a compromised
site yields only its own. Central attaches them through ControlPlaneCredentials,
which binds CallCredentials to the channel — covering unary and streaming
uniformly, and letting the key resolve asynchronously, which a client
interceptor could not do without blocking. All three central→site channel
creation sites go through it (SiteStreamGrpcClient and both audit pull invokers);
the pull invokers' channel caches are re-keyed by (site, endpoint) because
credentials are per-site and bound to the channel.
Two decisions beyond the plan:
* StartupValidator now requires GrpcPsk on Site nodes. The plan specified only
the runtime gate, but fail-closed with no boot check produces a node that
joins, answers heartbeats and reports healthy while refusing every stream,
audit pull and telemetry ingest — silent and total. Same reasoning as the
existing inbound API-key pepper rule.
* Added Communication:SitePsks as a central-side key map. The plan assumed
central would read the store, seeded via a dev KEK; the docker rig
deliberately boots with no master key, so store-only resolution would leave
it unable to dial its own sites. The store stays primary — it is the only
source that can serve a site added at runtime — with the map covering
key-less hosts and one-off pins. Neither source falling back to
"unauthenticated" is the invariant.
T0.4 — dev keys on both rigs and tests.
34 tests. The seven that matter most exercise a real in-process gRPC stack over
TestServer: the unit tests on either side of the wire would both stay green if
the halves disagreed, and gRPC refuses call credentials on a plaintext channel
by default — the UnsafeUseInsecureChannelCallCredentials opt-in is only provable
by making a real call. They confirm correct key passes on unary AND streaming,
wrong key and no-credentials both get PermissionDenied, and an unresolvable key
fails the call with nothing reaching the service.
OPERATIONAL: a site node upgraded to this build without a key will not boot.
That includes the gitignored deploy/wonder-app-vd03/ overlay.
Component Reference Documentation
Developer-reference docs for each ScadaBridge component, describing how the shipped
code in src/ actually works — with real code examples. These complement the
design specs in docs/requirements/: the specs say what a
component should do and why; these docs say how the code does it.
Reference docs exist for 24 of the 27 components (plus the shared TreeView, listed below). ScriptAnalysis (#25), KpiHistory (#26), and DelmiaNotifier (#27) are pending — tracked in ../plans/2026-07-08-deferred-work-register.md.
| # | Component | Description |
|---|---|---|
| 1 | Template Engine | Template modeling, inheritance, composition, flattening, diffs, and semantic validation as implemented by the engine's services. |
| 2 | Deployment Manager | The central deployment pipeline: deployment identity and idempotency, per-instance operation locks, state transitions, all-or-nothing site apply, and artifact deployment. |
| 3 | Site Runtime | The site actor hierarchy (Deployment Manager singleton, Instance, Script, and Alarm actors), script compilation and execution, the site-wide stream, native alarms, and supervision. |
| 4 | Data Connection Layer | Protocol adapters (OPC UA, MxGateway), the Become/Stash connection state machine, reconnect and re-subscribe, and the native-alarm subscription seam. |
| 5 | Central–Site Communication | ClusterClient command and control plus gRPC server-streaming, the central and site communication actors, receptionist registration, and per-site contact points. |
| 6 | Store-and-Forward Engine | Site-only buffering, fixed-interval retry, parking, SQLite persistence, standby replication, and the operation-tracking store. |
| 7 | External System Gateway | Script-facing HTTP/REST and database access, the Call and CachedCall modes, and transient versus permanent error classification. |
| 8 | Notification Service | Central notification-list and SMTP definitions, the per-type delivery adapters, and OAuth2 or Basic SMTP delivery. |
| 9 | Central UI | The Blazor Server app structure, authentication, real-time updates (SignalR and gRPC), and the management pages. |
| 10 | Security & Auth | LDAP bind authentication, cookie and JWT sessions, role-based and site-scoped authorization, and shared Data Protection keys. |
| 11 | Health Monitoring | Site metric collection and central aggregation, report and heartbeat intervals, offline detection, and dead-letter monitoring. |
| 12 | Site Event Logging | The site-local SQLite event log, retention and storage cap, daily purge, and paginated central query access. |
| 13 | Cluster Infrastructure | The ClusterOptions model and validation for active/standby clustering, split-brain resolution, and failover. |
| 14 | Inbound API | POST /api/{method} script invocation, API-key authentication, the extended type system, and inbound-request auditing. |
| 15 | Host | The deployable binary: role-based component registration, Akka bootstrap, ASP.NET Core hosting, and the readiness and active-node health endpoints. |
| 16 | Commons | Shared POCO entities, repository and service interfaces, message contracts, and the Types/Interfaces/Entities/Messages namespace layout. |
| 17 | Configuration Database | The EF Core DbContext, repository implementations, the audit service, secret encryption, and migration and partition maintenance. |
| 18 | Management Service | The ManagementActor admin command surface, its HTTP endpoints, and ClusterClientReceptionist registration. |
| 19 | CLI | The System.CommandLine tool over the HTTP Management API — its command groups, config file, and output formats. |
| 20 | Traefik Proxy | The reverse proxy fronting the central cluster, active-node routing via /health/active, and the Docker topology configuration. |
| 21 | Notification Outbox | The central NotificationOutboxActor, the Notifications table, the dispatcher loop, retry and parking, and KPIs. |
| 22 | Site Call Audit | The central SiteCallAuditActor, the SiteCalls mirror table, telemetry ingest, and the parked-call Retry/Discard relay. |
| 23 | Audit Log | The append-only audit store: site SQLite hot-path, gRPC telemetry, central ingest and reconciliation, redaction, retention, and KPIs. |
| 24 | Transport | Encrypted bundle export and import, dependency resolution, conflict detection, and BundleImportId-correlated audit. |
| 25 | Tree View | The reusable Blazor tree component — parameters, selection modes, and usage in the Central UI. |
Related Documentation
- Component design specs — the spec each component implements.
- Documentation Style Guide — the writing conventions these docs follow.
- README — the repository master index.