Nine drivers raise IRediscoverable.OnRediscoveryNeeded when they observe that
a remote's tag set may have changed — a Galaxy redeploy, a TwinCAT
symbol-version bump, an MTConnect agent restart, a Sparkplug rebirth. Nothing
in src/ subscribed, so every raise went into the void. Drivers even wrap the
invoke in try/catch for "subscriber threw"; there has never been a subscriber.
DriverInstanceActor now attaches the event in PreStart and detaches in
PostStop, mirroring AttachAlarmSource/DetachAlarmSource. Attach is per-actor,
not per-connect: the raise has no connection affinity and can land while the
driver is between connects. The detach is load-bearing rather than tidy — the
IDriver instance outlives the actor when the host respawns a child around the
same driver object, so a missing -= accumulates one handler per respawn, each
holding a dead Self.
The signal rides the existing driver-health snapshot to /hosts as a
"re-browse" chip. It is ADVISORY: the served address space is deliberately not
rebuilt, because v3 authors raw tags explicitly through the /raw
browse-commit flow and a runtime graft would materialise nodes no operator
approved and no deployment artifact records.
Two things worth knowing:
- PublishHealthSnapshot dedups on a health fingerprint, and a rediscovery
raise on an otherwise-healthy driver changes none of the four fields it
hashed. Without adding the timestamp to that tuple the dedup swallows the
exact publish carrying the signal. Reverting that one line turns 3 of the 5
new tests red, which is how it was confirmed rather than assumed.
- The new test stub implements IDriver from scratch instead of deriving from
the shared StubDriver, whose GetHealth() returns DateTime.UtcNow — its
fingerprint differs on every call, so the dedup never engages and the dedup
test would have passed vacuously either way.
The planned discovery-result drift detector was NOT built. Modbus, S7, MQTT,
AbLegacy and Sql all echo authored config from DiscoverAsync rather than
browsing the device, so a discovered-vs-authored diff is permanently empty for
them — it would have been another plausible-looking inert seam, which is the
class this audit exists to remove. IRediscoverable is the trustworthy signal
because the driver asserts it deliberately.
DriverHealthChanged, IDriverHealthPublisher.Publish and HostsDriverRow gain
defaulted optional parameters, so no existing call site changed. telemetry.proto
gains fields 8/9 and both Phase-5 mappers carry them.
Runtime.Tests 512 passed / 31 skipped.
Each of the four telemetry publish seams now also emits its DPS payload into the
node-local ITelemetryLocalHub (Phase 5), leaving the existing DistributedPubSub
publish untouched:
- driver-health AkkaDriverHealthPublisher -> TelemetryItem.Health
- resilience DriverResilienceStatusPublisherService -> TelemetryItem.Resilience
- alerts ScriptedAlarmHostActor + DriverHostActor (native) -> TelemetryItem.Alarm
- script-logs VirtualTagActor + DpsScriptLogPublisher -> TelemetryItem.Script
DI services take the hub as a required ctor param; actors take an optional
nullable hub threaded through their Props and the real spawn sites
(DriverHostActor <- ServiceCollectionExtensions; VirtualTagActor/ScriptedAlarmHostActor
<- DriverHostActor), so existing test Props constructions keep compiling and simply
do not emit. The hub is a no-op until a gRPC client subscribes, so the emit is safe
on every node.
Claude-Session: https://claude.ai/code/session_01GASWkNEi68FSCtvr6rLoEW
- Topic-name drift fix: DriverHealthChanged.TopicName and
DriverControlTopic.Name now live on the message contracts in
Commons. AkkaDriverHealthPublisher, DriverStatusSignalRBridge,
DriverHostActor, and AdminOperationsActor all delegate to the
single constant so a rename can't silently desynchronise
publisher and subscriber.
- DriverStatusPanel._opResultClearTimer switched from
System.Timers.Timer to System.Threading.Timer + awaited
DisposeAsync. Prevents an in-flight 8s clear-callback from
invoking StateHasChanged on a component whose hub has already
been released.
- PublishHealthSnapshot deduplicates against the last published
(state, lastSuccess, lastError, errorCount) fingerprint. The
30s heartbeat no longer floods the SignalR layer with identical
Healthy snapshots — newly-joined clients still warm up via the
snapshot store on JoinDriver.
- IDriverHealthPublisher in Core.Abstractions + NullDriverHealthPublisher
no-op for tests/dev-stub paths.
- AkkaDriverHealthPublisher in Runtime forwards to the cluster-wide
`driver-health` DPS topic.
- DriverInstanceActor instrumented to publish snapshots on every
observable state change + a periodic 30s heartbeat so the AdminUI
snapshot store warms up for newly-joined SignalR clients.
- Sliding 5-minute Faulted-count tracked per actor via Queue<DateTime>.
- DriverHostActor.SpawnChild threads clusterId (_localNode.Value) and
the health publisher down to every DriverInstanceActor child.
- ServiceCollectionExtensions.AddOtOpcUaRuntime registers
AkkaDriverHealthPublisher as IDriverHealthPublisher singleton.
Joseph Doherty