Render Fallback:Mode=ForceSubtag as a cyan 'Subtag monitoring (forced)'
badge, distinct from the amber failover 'degraded' badge, so an intentional
configuration isn't shown as a fault. Distinguished by the shared
AlarmProviderReasons.ForcedSubtag reason carried on the provider-status feed.
Implements the actionable deferred items from pending.md (B1-B5, C6-C7):
- B1/B2 metrics: provider-switch count in snapshot + bounded reason enum
- B5: drop dead primitive branch from AlarmAttributesSql
- B3/B4 worker: UnAdvise only advised handles (+Dispose tests); remove dead field
- C6/C7: doc clarifications and design-doc superseded notes
Verified: gateway tests on macOS, net48/x86 worker suite (318 passed) on windev.
C6a: the rig's TestAlarm attributes are object-driven; a flip script OR a manual
operator/IDE toggle drives them (confirmed live 2026-06-14). Update the how-to-run
comments and Skip reason accordingly.
B3: track advised handles separately from added handles so Dispose only UnAdvises
items that were actually advised — a write-only subtag (e.g. ack-comment added by
Write, never advised) is removed but not unadvised. Add Dispose tests covering the
advised/write-only split, full removal, single Unregister, and double-dispose
idempotency.
C6b: IAlarmWatchListResolver.ResolveAsync doc now notes that while discovery being
unavailable never throws, a triggered cancellation token still propagates.
C7: annotate the original design doc where it drifted from the shipped code — metric
names / unimplemented watch-list gauges, and the proto-type location (gateway proto, not
worker proto).
B5: the candidate CTE's src_pri=1 (primitive-instance) UNION ALL branch was always
excluded by the final WHERE r.src_pri=0, so it added work with no output change. Remove
the branch and the now-constant src_pri column/filter. An alarm anchor is always a user
attribute, so output is identical.
B1: add AlarmProviderSwitchCount to GatewayMetricsSnapshot so the switch total is
readable without scraping the OTEL counter.
B2: replace the free-text reason tag on mxgateway.alarms.provider_switches with a
bounded AlarmProviderSwitchReason enum (failover/failback/unknown); the human-readable
reason stays in the structured log.
Adds AlarmSubtagLiveSmokeTests to validate the open design item from Task 17:
confirms that LmxSubtagAlarmSource (real MxAccessComObjectFactory) wired to
SubtagAlarmConsumer synthesizes degraded Raise transitions with stable synthetic
GUIDs from Galaxy alarm subtags, and that AcknowledgeByName writes the
ack-comment subtag (rc=0). PLACEHOLDER_* subtag addresses are best-guess and
must be verified against MXAccess-Public-API.md + live Galaxy before flipping Skip.
Keeps committed generated C# in sync with the .proto change in 1d85db7
(AlarmProviderMode, AlarmSubtagTarget, AlarmFailoverConfig, AlarmProviderStatus,
OnAlarmProviderModeChangedEvent, degraded/source_provider fields).
Joseph Doherty