The truncation-cliff fix made alarm transitions truncation-safe but silent:
when GetXmlCurrentAlarms2 returns exactly maxAlmCnt records the worker
suppresses absence-implies-Clear inference and says so only in a rate-limited
stderr warning. No client and no operator could tell a complete active set
from a capped one.
Two additive proto3 booleans carry the verdict out:
- QueryActiveAlarmsReplyPayload.snapshot_truncated = 2 (worker IPC reply)
- ActiveAlarmSnapshot.from_truncated_snapshot = 16 (per record)
The per-record field is not an aesthetic choice. QueryActiveAlarms returns a
bare `stream ActiveAlarmSnapshot` with no envelope, header, or trailer, so a
per-record boolean is the only carrier that stays wire-compatible; an envelope
message would change every existing client's stream element type. The reply
payload states it too because a prefix filter can leave zero records and a
truncated fetch with nothing to report still has to say so. The flag means
"this set may be incomplete", never "this record is unreliable" — it is
independent of the subtag-fallback `degraded` field.
Detection is deliberately UNCHANGED: IsTruncatedFetch remains
`fetchedRecordCount >= maxAlarmsPerFetch`. The live probe (docs/AlarmProbeFindings.md,
ce5d8ae) could not verify whether ALARM_RECORDS/@COUNT reports the total active
count or only the records in the reply, so @COUNT is not parsed for detection;
switching to it stays blocked on probe evidence. The probe's comment
annotations in WnWrapAlarmConsumer.cs are preserved.
Reset semantics: not latched. WnWrapAlarmConsumer.FoldFetch replaces the
verdict on every poll under the same lock as the snapshot merge, so the first
sub-cap fetch clears it; GatewayAlarmMonitor.ClearCache drops it with the cache
generation it describes. A caveat that never turns off is one operators learn
to ignore.
Flow: WnWrapAlarmConsumer.LastSnapshotTruncated -> AlarmDispatcher (stamps every
record) / IAlarmCommandHandler (payload) -> MxAccessCommandExecutor reply ->
GatewayAlarmMonitor._snapshotTruncated -> IGatewayAlarmService.SnapshotTruncated
-> DashboardAlarmQueryResult -> AlarmsPage warning banner (render-side only; the
poll loop and DisposeAsync drain are untouched). The public QueryActiveAlarms
RPC forwards worker snapshots unmodified, so the per-record flag needed no
mapper change — a test pins that.
Parity: this describes OUR fetch mechanics — additive gateway metadata — not
MXAccess provider behavior. No event is synthesized and no MXAccess-observable
semantics change, so it is not a parity deviation.
Tests: worker LastSnapshotTruncated set/reset/consecutive-burst (windev-run);
gateway end-to-end truncated reply -> monitor -> public stream, with the
complete-reply control as the load-bearing assertion; AlarmsPage banner
present/absent. Docs: gateway.md alarm surface, docs/DesignDecisions.md entry.
Add docs/plans/2026-07-10-dashboard-session-acl-tst15.md: the fleshed-out
Phase-4 design for the deferred TST-15 finding. Resolves the crux the deferral
left open — the dashboard authenticates LDAP users (Admin/Viewer) while sessions
are API-key-owned (OwnerKeyId), two disjoint identity domains — via a session tag
sourced from the owning API key (carried in the existing ApiKeyConstraints JSON
blob, no SQLite migration). Admin-sees-all; a Viewer may SubscribeSession iff
session.Tags intersects the Viewer's granted tags (new Dashboard:GroupToTag map
-> hub-token tag claims); untagged sessions Admin-only by default. Includes the
enforcement path, task breakdown (epic Tasks 16-19), test plan incl. live-LDAP,
and rejected alternatives.
Design only — TST-15 stays Not started (no implementation). The tracker and the
60-testing-docs-gaps TST-15 section point at the design doc; the change-log also
records the TST-03 finding (zero registered runners; needs a runner co-located on
the gitea Docker network).
Claude-Session: https://claude.ai/code/session_01DMXXvNuPekkkrTEyPNxEkW
Joseph Doherty