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docs: correct stale LDAP-role, host-probe, resilience-table, Bad-value claims; fix tasks.json (#624)

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Claude-Session: https://claude.ai/code/session_01Ef2ozxS7QPanGT8uoATbTe
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Joseph Doherty
2026-10-08 08:16:43 -04:00
parent f383996127
commit 2befe9f9ba
13 changed files with 42 additions and 28 deletions
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docs/DriverLifecycle.md
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@@ -311,12 +311,18 @@ shutdown paths deliberately keep the single trailing write.
> **A value consumer never reports a quality better than its source's.** A node derived from a driver
> value — the raw node, every UNS mirror, a Calculation output, a virtual tag, a scripted condition's
> quality — carries, at worst, the worst status among its inputs: a Bad input makes the derived node Bad
> **with that input's sub-code and the last-known value**; an Uncertain input makes it Uncertain; a source
> **with that input's sub-code** (the last-known value is kept server-side, but see the note below: a client never sees it beside a Bad status); an Uncertain input makes it Uncertain; a source
> that has stopped communicating is a Bad input (`BadNoCommunication`) for everything downstream of it,
> **including the external OPC UA data plane**. Recovery is a *publish*, never an assumption: the first
> post-recovery value must land even when it equals the value held before the outage, so every dedup on
> the path — driver caches, the node's own status, a consumer's last-published memory — must be keyed on
> **(value, status)**, not value alone.
>
> **"Value retained" is server-side state, not wire-observable.** The node keeps its last value under the
> Bad status (that is what lets the next Good re-publish carry it and what the `(value, status)` dedup
> compares against), but the OPC UA SDK's `NodeState.ReadAttribute` nulls the value of any Bad-status read
> and monitored-item sample, so a client sees `Value = null` with the Bad status and never the last-known
> value. Pinned server-side by `OtOpcUaNodeManagerWriteStatusesTests`; observation: `archreview/plans/R3-02-stale-good-family-plan.md`.
This is one rule with one implementation of its comparison,
`ZB.MOM.WW.OtOpcUa.Core.Abstractions.InputQuality` (`WorstOf` / `IsUsable`), used by every derived-value
@@ -325,7 +331,7 @@ a fifth (archreview round 3, theme "the stale-Good family"). The seams that impl
| Seam | What it does | Where |
|---|---|---|
| Driver comms loss → **value nodes** | one status-only batch stamps `BadNoCommunication` on the driver's raw NodeIds and every referencing UNS NodeId, **value retained** | `DriverHostActor.FanCommsLossToValueNodes` (below) |
| Driver comms loss → **value nodes** | one status-only batch stamps `BadNoCommunication` on the driver's raw NodeIds and every referencing UNS NodeId, **value retained server-side** (clients see a null value with the Bad status) | `DriverHostActor.FanCommsLossToValueNodes` (below) |
| Driver comms loss → dependency mux | synthetic Bad per ref, so scripts and alarms see the source die | `DriverHostActor.FanCommsLossToDependencyMux` |
| Driver comms loss → Part 9 conditions | condition quality annotated out of band | `DriverHostActor.OnDriverConnectivityChanged` |
| MQTT / Sparkplug | connection loss stales observed refs; every (re)subscribe pushes the cached snapshot | [`docs/drivers/Mqtt.md`](drivers/Mqtt.md#quality-on-connection-loss-and-re-subscribe) |