RediscoverPolicy is now mode-dependent: UntilStable in Sparkplug B (a tag's
dataType is optional -- the birth certificate declares it, so the discovered
tree fills in asynchronously), Once in Plain (nothing about the authored set
arrives on the wire).
DiscoverAsync resolves each Sparkplug tag's datatype per pass from the live
BirthCache, with the ingest path's own precedence: authored dataType wins,
else the birth's, else the record default. An unsupported Sparkplug type
(DataSet/Template/PropertySet/Unknown) falls back rather than blanking the
tag. The authored tag SET is never conditional on a birth -- an authored tag
is part of the declared configuration, not something the plant grants by
publishing.
SparkplugIngestor.BirthObserved is wired to RaiseRediscoveryNeeded behind a
two-part change gate, which is the anti-storm mechanism rather than an
optimisation: fire only for a scope an authored tag binds, and only when the
birth's metric-name SET (ordered-distinct, ordinal) differs from the last one
seen for that scope. Edge nodes re-birth freely -- on their own timer, on
every reconnect via the late-join rebirth fan-out, and once per rebirth NCMD
the gap policy sends -- and firing on each of those would make a healthy plant
a permanent address-space-rebuild loop. No extra debounce: what survives the
gate is a real edit to the served tree, and delaying it would need its own
trailing-edge flush to avoid dropping the last change.
The signature map is NOT cleared on death/reconnect/ingest rebuild (the
ingestor drops its whole birth cache on reconnect, but "the driver forgot" is
not "the address space changed"); it is pruned when a redeploy stops
authoring a scope.
ScopeHint is the "Mqtt" discovery folder, deliberately not the Sparkplug scope
path the plan named: the discovered tree is flat, so an edge-node/device path
would name a subtree that does not exist and a consumer scoping a rebuild on
it would rebuild nothing. The scope is carried in Reason instead.
Falsifiability: always-fire reddens the identical-rebirth + reordered-rebirth
pins; always-authored-datatype reddens the birth-fill pin; dropping the
authored-scope filter reddens the unauthored-device pin. 524/524 MQTT unit
tests green (was 513).
Claude-Session: https://claude.ai/code/session_01GASWkNEi68FSCtvr6rLoEW
C1 (Critical) — DisposeAsync went straight to TeardownAsync with no lifecycle-gate
wait, reopening the orphaned-connection class. Interleaving: ReinitializeAsync's
rebuild branch holds the gate mid-InitializeCoreAsync, past its own teardown but
before `_connection = connection`; an ungated dispose sees a null connection, does
nothing, and sets `_disposed`; the rebuild then publishes a live connection plus a
host-probe loop that every later dispose short-circuits past. Not proven reachable
today (DriverInstanceActor.PostStop calls the gated ShutdownAsync), but MqttDriver
publicly implements IAsyncDisposable, which invites `await using`.
- DisposeAsync now takes the gate with the same bounded wait + fallback teardown
ShutdownAsync uses, and sets `_disposed` BEFORE the wait.
- InitializeCoreAsync re-checks `_disposed` after the connect and disposes the
connection it just built rather than publishing it — this closes the residual
window on the bounded-timeout fallback path.
- The doc comment no longer claims parity with ShutdownAsync it did not have, and
stops conflating "don't Dispose() the semaphore object" with "don't WaitAsync".
I1 (Important) — the SameSession == false rebuild branch had no test driving it.
Adds three: an endpoint-changing delta rebuilds and Faults on a refused connect;
an ingest-only delta (MaxPayloadBytes) ALSO rebuilds, pinning that IngestIdentity
is nested inside SessionIdentity; and DisposeAsync serializes behind a lifecycle
operation parked at a new internal BeforeConnectHookForTests seam (mirroring
MqttConnection's AfterConnectHookForTests, which exists for the same race class).
Minors: comments recording that IngestIdentity names no Sparkplug field and must
grow one in P2 (tasks 21/22), and why _options/_subscriptions/_authoredRawPaths
get looser memory discipline than _health/_hostState.
Falsifiability: reverting DisposeAsync to the ungated form reddens exactly the new
serialization test ("Shouldly.ShouldAssertException : raced"); forcing SameSession
to always-true reddens exactly the two new rebuild tests. 240/240 MQTT tests pass;
forced rebuild of the driver project is 0 warnings under TreatWarningsAsErrors.
Claude-Session: https://claude.ai/code/session_01GASWkNEi68FSCtvr6rLoEW
Composes MqttConnection + MqttSubscriptionManager + LastValueCache into the
IDriver / ITagDiscovery / ISubscribable / IReadable / IHostConnectivityProbe /
IRediscoverable capability set.
- Discovery replays ONLY the authored raw tags (RediscoverPolicy = Once,
SupportsOnlineDiscovery = false) — a chatty broker can never auto-provision.
- Composition order is register -> AttachTo -> ConnectAsync; the manager's
Reconnected handler is passed through unwrapped so its throw-on-total-failure
still tears a deaf session down.
- ReinitializeAsync applies a tag-only delta in place and never faults on a bad
one; a session-changing delta rebuilds.
- ReadAsync serves the last-value cache and degrades per reference
(BadWaitingForInitialData), never throwing for the batch.
- FlushOptionalCachesAsync is a no-op: the last-value cache IS IReadable.
- Adds MqttDriverOptions.RawTags (the authored-tag delivery mechanism every
other driver's options DTO already has) and promotes MaxPayloadBytes from a
manager ctor knob to an operator-facing key.
- Converges on MqttDriverProbe.JsonOpts rather than a second, divergent
JsonSerializerOptions.
Claude-Session: https://claude.ai/code/session_01GASWkNEi68FSCtvr6rLoEW
Joseph Doherty