The ContinuousHistorizationRecorder was spawned with an EMPTY historized-ref
set, so it registered interest in nothing and historized nothing. This feeds it
the currently-historized tag refs on every address-space deploy/redeploy so its
DependencyMuxActor interest converges to exactly the historized set (the same
refs the EnsureTags provisioning hook resolves: override-or-FullName).
Design — delta convergence (the plan is a pure DIFF):
- New seam IHistorizedTagSubscriptionSink (Core.Abstractions/Historian) with a
Null no-op singleton, mirroring how IHistorianProvisioning decouples the T15
hook. AddressSpaceApplier gains a DEFAULTED ctor param (Null sink) so all ~80
existing call sites + the production site compile unchanged.
- Apply() only ever sees a plan diff (an incremental/surgical apply carries a
delta, not the full set), so the applier feeds an add/remove DELTA computed
from AddedEquipmentTags / RemovedEquipmentTags / ChangedEquipmentTags. The
recorder keeps the full set and re-registers it. The feed is a single
non-blocking Tell behind the sink, wrapped in try/catch so a faulting feed
never blocks or breaks a deploy (same discipline as the provisioning hook).
- Recorder.UpdateHistorizedRefs(added, removed) converges the tracked set, then
— only when it actually changed — sends ONE RegisterInterest with the full set
(the mux's RegisterInterest is a full-REPLACE) or one UnregisterInterest when
it drains to empty (the mux has no per-ref unregister). An unchanged delta is
a no-op (no mux churn).
- DI: the recorder is now spawned BEFORE the applier so the adapter
(ActorHistorizedTagSubscriptionSink) can wrap its IActorRef; the Null sink is
used when continuous historization is off/unwired.
Tests: recorder convergence (add-from-empty, add+remove converge, idempotent,
drain-to-empty unregisters); applier feeds resolved added refs, removed+renamed
deltas, and survives a throwing sink. Build clean (0 warnings on touched
projects); Runtime/OpcUaServer/Gateway/AdminUI suites green.
Claude-Session: https://claude.ai/code/session_012SDSQ3AcaXqPcBtDESBRii
Joseph Doherty