feat(mqtt): Sparkplug ingest state machine (birth/alias/seq/rebirth/death→stale)
Task 21 — the design doc's §3.6 correctness core. `SparkplugIngestor` owns the
authored `(group, node, device?, metric) → RawPath` index, the live `BirthCache`,
one `SequenceTracker` per authored edge node, and the rebirth policy; it routes
NBIRTH/DBIRTH/NDATA/DDATA/NDEATH/DDEATH/STATE into `OnDataChange` +
`LastValueCache`, or into a bounded, per-node-debounced rebirth NCMD.
Invariants held (and each pinned by a falsifiability control):
- Published reference is the RawPath, never a composed Sparkplug reference —
`DriverHostActor`'s dual-namespace fan-out is RawPath-keyed.
- Tags bind by stable metric NAME; the alias is only the per-birth lookup, so an
alias reused across a rebirth cannot mis-route.
- Every value goes through `SparkplugMetricBinding.Reinterpret` before publish.
- NDEATH never reaches `SequenceTracker.Accept` (it carries no seq); it is tied to
its birth by bdSeq instead.
- An invalid payload mutates nothing — no tracker, no alias table, no eviction.
- `HandleMessage` never throws on MQTTnet's dispatcher thread.
Supporting changes:
- `MqttTagDefinitionFactory.FromSparkplugTagConfig` — the driver had no way to
parse the Sparkplug descriptor keys at all; the P1 stub fields on
`MqttTagDefinition` were never populated. Mode selects the parser, never a
blob heuristic. `dataType` becomes optional in the Sparkplug shape (the birth
declares it), recorded via the new `DataTypeAuthored` flag.
- `MqttConnection` implements `IMqttPublishTransport` (bounded, refusal throws).
- `MqttDriver` dispatches every capability by mode, subscribes `spBv1.0/{group}/#`
(+ the configured STATE topic) once at connect, and re-subscribes + requests a
late-join rebirth on reconnect. `IngestIdentity` now names `MqttSparkplugOptions`,
closing the silent same-ingest gap its own ⚠️ comment warned about.
Primary-host STATE *publishing* is explicitly out of scope and warned about at
construction: it needs the retained-OFFLINE Last Will set at CONNECT time, and
shipping the ONLINE half alone is worse than shipping neither.
58 new tests (MQTT suite 455 → 513, all green).
Claude-Session: https://claude.ai/code/session_01GASWkNEi68FSCtvr6rLoEW
This commit is contained in:
Joseph Doherty