Second slice of the 2026-09-09 whole-system review remediation
(docs/plans/2026-09-09-arch-review.md §10), on top of the High slice 146a1323.
Runtime/devices: SR-2 alarm on-trigger integration scope; SR-3 correlated NativeAlarmActor
subscribe retry; SR-4 immutable audited DB target; SR-5 ordered InstanceActor stop/flush;
SR-12 rehydration fence; SR-13 S&F gate recheck per delivery; DC-4 no OPC UA security
downgrade; DC-5 alarm snapshot for every new subscriber; ORCH-1 sync-dispose joins the pump.
Management/UI: MG-2 site scope on audit tree + Flow Debugger Replay; MG-3 stale-probe memo
removed; MG-4 server-owned bulk-deploy deadline; UI-5 sandbox runs in a killable child
process (new CentralUI.SandboxWorker project); UI-14 bounded sandbox output/IPC.
Edge/audit: EI-1 relay audit ownership; EI-2 SkipBodyCapture suppresses error text; EI-3/EI-11
error-field redaction + caps; EI-4 single relay deadline, pre-execution-only retry; EI-5
authenticated relay provenance; EI-10 body cap before audit read.
Persistence/contracts: DL-1 global Instance.UniqueName unique index + conflict translation;
DL-2 DataConnection protocol config encrypted at rest (migration
20260909203046_EnforceGlobalInstanceNamesAndProtectProtocolConfiguration — coordinated
central upgrade, old binaries cannot read protected rows); DL-3 bounded Replay paging;
DL-6 cross-site Overwrite of a deployed instance rejected; XC-4 proto descriptor contract test.
Config/hygiene: XC-1 central listener isolation by local port; XC-2/XC-3 inert SMTP + cron
keys removed from rig settings; CM-2 env2 bootstrap guard enabled; DC-6 deploy site exit code;
DC-7 notifier retries only explicit standby rejection; XC-5 ClusterClient purged from docs.
Gates recorded in the report: build 0/0, 9 397 passed / 0 failed, rig redeployed on all
eight nodes with the migration applied. 46 Low findings remain open.
The single-writer queue (d91135f9) made RecordEnqueueAsync return on enqueue, so the
test's verifier-connection UPDATE raced the pump and touched zero rows whenever the pump
lost. Every other verifier-connection test already flushed; this one was missed.
Claude-Session: https://claude.ai/code/session_01NcMG6xXdsJbmD2wYAgkK29
A Flow Debugger live run (execution 1130c01f) spent 108 of a 176 ms site script run
between the cached DB write completing and Notify.Send starting: the immediate-
completion telemetry awaited two autocommit SQLite transactions on the consolidated
LocalDb file (RecordAttemptAsync + RecordTerminalAsync), on the script thread, each a
WAL fsync on a Docker volume; the submit row was a third. The audit half of the same
forwarder was already a channel write, so the tracking half was the whole cost.
OperationTrackingStore is now a single-writer queue: Record*Async enqueue an ordered
work item and return; one background pump drains the bounded channel (8192, wait
backpressure - tracking never drops) and applies each batch (<=256) in ONE transaction,
falling back to per-row apply when a batch fails so a poison row cannot take its
neighbours. Preserved invariants: FIFO across enqueue/attempt/terminal; read-your-
writes (GetStatusAsync and ReadChangedSinceAsync barrier on every write queued before
them, skipped when idle) so Tracking.Status, the telemetry actor's status join and
central's PullSiteCalls never see a stale row; timestamps stamped when recorded;
PurgeTerminalAsync returns after the purge lands; DisposeAsync drains the queue before
closing; sync Dispose keeps its documented in-flight-writes-fail semantics. New public
FlushAsync() is the explicit barrier. Accepted: a queued-but-unapplied row is lost on a
hard crash (ms window); S&F buffer and audit rows are unaffected.
No interface, forwarder or ScriptRuntimeContext change. Tests: write returns while
another connection holds the DB write lock and lands once released (fails on the old
store: 31 s); reads see 100 ordered attempts + terminal; DisposeAsync drains 200
queued rows; write after dispose throws ObjectDisposed. Existing tests that poke the
SQLite file right after a store call now FlushAsync first.
Claude-Session: https://claude.ai/code/session_01NcMG6xXdsJbmD2wYAgkK29
Task 4 of the LocalDb Phase 1 adoption plan.
OperationTrackingStore took IOptions<OperationTrackingOptions> and opened its own
SqliteConnection from ConnectionString. It now takes ILocalDb and gets every
connection - writer and the two ad-hoc reader paths - from CreateConnection().
This is not cosmetic. OperationTracking is a RegisterReplicated table, so its
capture triggers call zb_hlc_next(). That UDF is registered per connection by
ILocalDb and by nothing else, so a raw SqliteConnection would fail closed on
every write. Connections from CreateConnection() also arrive already open -
calling Open()/OpenAsync() on one throws - hence the removed OpenAsync calls on
the reader paths.
OperationTrackingOptions.ConnectionString is now vestigial for this store; the
database location is LocalDb:Path. The options class stays (retention settings)
and the config key stays bound for the site config DB.
InitializeSchema is kept but is now always a no-op in the host: onReady runs
while ILocalDb is being constructed, strictly before this constructor can
receive it. It remains so a directly-constructed store (tests, tooling) is
self-sufficient.
Tests: the store fixture moves off mode=memory&cache=shared onto a real ILocalDb
over a temp file. There is no in-memory mode - LocalDbOptions.Path is a
filesystem path - and testing through a raw in-memory connection would no longer
resemble the host. Verifier connections stay raw on purpose: this fixture never
registers the table, so no trigger fires and the UDF is never reached.
Three DI fixtures needed LocalDb:Path added, because resolving
IOperationTrackingStore now forces ILocalDb construction:
SiteCompositionRootTests, SiteAuditWiringTests, and the AuditLog
CombinedTelemetryHarness.
Verified: build 0 warnings; Host 294/294, SiteRuntime 530/530, AuditLog 354/354.
Claude-Session: https://claude.ai/code/session_01BL2Vu1ESDQ9SCN4gVKkdts
Tasks 2 + 5a-writer + 5b of the LocalDb Phase 1 plan, landed together because
they are one indivisible change: the schema, the writer that fills it, and every
consumer that assumed the old id semantics.
WHY the id changes. Site pairs will replicate site_events with last-writer-wins on
the primary key. With INTEGER PRIMARY KEY AUTOINCREMENT both nodes independently
mint 1, 2, 3... for unrelated events, so sync would treat them as the same row and
silently overwrite. A GUID makes the event log a pure union across the pair.
Task 2 - schema extracted so the Host's AddZbLocalDb onReady can create the tables
before RegisterReplicated installs capture triggers (pre-registration rows are
never captured):
- new OperationTrackingSchema.Apply / SiteEventLogSchema.Apply, plain
Microsoft.Data.Sqlite, no LocalDb dependency
- both stores delegate their InitializeSchema to them (idempotent, so a
directly-constructed store still works)
- OperationTracking is unchanged - it already had a TEXT PK and replicates as-is
Task 5a - SiteEventLogger mints Guid.NewGuid("N") per event and inserts it.
Task 5b - three consumers assumed a monotonic integer id. All three move to
timestamp ordering; leaving any one behind would be a live bug:
- EventLogQueryService: "id > $afterId" would return an ARBITRARY subset of a
GUID-keyed table and SILENTLY DROP ROWS from page-through. Now a composite
(timestamp, id) keyset cursor with an opaque string token; timestamps are not
unique, so id is the tie-break that guarantees exactly-once paging.
- EventLogPurgeService: "ORDER BY id ASC LIMIT 1000" would delete a RANDOM batch
instead of the oldest. Now orders by timestamp.
- EventLogEntry.Id and both ContinuationTokens: long -> string.
WIRE COMPATIBILITY. Those DTOs cross the site<->central Akka boundary
(SiteCommunicationActor -> CommunicationService -> ManagementActor / CentralUI).
No rolling-upgrade shim is needed because both sides ship in the same deployable
and the rig redeploys as a unit. Checked: no Akka serializer binding pins these
types by name. A stale numeric token degrades to "start from the beginning"
(a visible repeat) rather than throwing or losing rows.
Tests: the two that encoded the old semantics were rewritten to guard the new
invariant rather than deleted - uniqueness instead of monotonicity, and
oldest-purged-first keyed on timestamp. That second test also exposed a latent
weakness: the bulk seed stamped every row with the same UtcNow, so "oldest" was
never actually well-defined; rows now get distinct increasing timestamps, kept
inside the retention window so the retention purge does not eat them first.
Verified:
dotnet build ZB.MOM.WW.ScadaBridge.slnx -> 0 Error(s), 0 Warning(s)
SiteEventLogging.Tests -> 70 passed (12 new schema tests, red-first)
CentralUI.Tests -> 925 passed
Commons.Tests -> 684 passed
SiteRuntime.Tests -> 529 passed, 1 pre-existing flaky failure
(InstanceActorChildAttributeRaceTests - passes 3/3 in
isolation with and without this change)
Claude-Session: https://claude.ai/code/session_01BL2Vu1ESDQ9SCN4gVKkdts
VERIFY-THEN-FIX: the plan-authoring discovery is CONFIRMED. No code anywhere in
src/ registered IOperationTrackingStore in DI, yet AkkaHostedService and
AuditLog SCE both comment that AddSiteRuntime provides it. Every consumer
resolved it via GetService (null-tolerant) and silently ran degraded:
cached-drain scheduler never armed, PullSiteCalls reconciliation seam never
wired, Tracking.Status degraded to audit-only. This is a FUNCTIONAL FIX riding
the hygiene plan: AddSiteRuntime now registers the store (site-only), so
site-local cached-call tracking runs in its intended mode. OperationTrackingOptions
is now bound + eagerly validated in the Host site-options block.
Site side: additive proto after_id field, ReadChangedSinceAsync gains an optional
afterId cursor and deterministic (UpdatedAtUtc, TrackedOperationId) ordering — a
batch fully inside one UpdatedAtUtc instant no longer re-reads the same page
forever. Absent/empty afterId preserves the exact legacy inclusive >= contract, so
an older central is unaffected. Regenerated the checked-in gRPC C#.
Site Call Audit (#22): build the documented periodic reconciliation PULL
self-heal path for the eventually-consistent central SiteCalls mirror, as a
dedicated PullSiteCalls gRPC RPC kept separate from the audit pull. This is the
pull PLUMBING only; the central reconciliation tick is a separate follow-up.
- IOperationTrackingStore.ReadChangedSinceAsync(sinceUtc, batchSize): inclusive
UpdatedAtUtc cursor, oldest-first, batch-capped; SQLite impl projects tracking
rows onto SiteCallOperational (Kind->Channel, TargetSummary->Target, SourceSite
left empty - the store has no site-id column).
- sitestream.proto: rpc PullSiteCalls + PullSiteCallsRequest/Response, mirroring
PullAuditEvents; regenerated checked-in SiteStreamGrpc/*.cs.
- SiteCallDtoMapper.ToDto(SiteCallOperational): inverse of FromDto for the handler.
- SiteStreamGrpcServer.PullSiteCalls handler + SetOperationTrackingStore seam;
Host wires the seam alongside SetSiteAuditQueue (site roles only).
- Central IPullSiteCallsClient + GrpcPullSiteCallsClient (home: AuditLog/Central to
reuse ISiteEnumerator; SiteCallAudit does not reference AuditLog). Re-stamps
SourceSite from the dialed siteId; no-throw on tolerable transport faults;
SpecifyKind (not ToUniversalTime) cursor handling. Central-only DI registration.
Tests: ReadChangedSinceAsync (4), PullSiteCalls handler (6), GrpcPullSiteCallsClient
(8). Full solution build 0 warnings/0 errors (TreatWarningsAsErrors).
Joseph Doherty