The default decider restarts a faulting child immediately and without limit, and
the hook makes every restart do ShutdownAsync+InitializeAsync+SubscribeAsync, so a
driver faulting on every value became a reconnect storm. Per-driver last-reprovision
stamp + DefaultReprovisionBackoff (10s, matched to DefaultReconnectInterval);
a held request is re-delivered by a single per-driver timer carrying the original
incarnation ref, so the F2 identity check still applies.
Seen RED with the backoff disabled: InitializeCount == 3 (second applied
immediately) where the test requires 2-then-3.
Also: the _children.Keys union-arm test (seeder gained taglessDrivers) and the
_desiredByDriver xmldoc note that it lingers on last-known-good after a failed apply.
A ReprovisionRequested in flight from an old incarnation could reach the NEW child
after HandleRestartDriver swapped it in. In Connecting that child DOES handle
InitializeRequested, so it started a second concurrent InitializeAsync, racing the
#527 dispose-before-overwrite.
Seen RED: InitializeCount == 2 on a child held in Connecting by a gated init
(an already-connected child swallows InitializeRequested and passes vacuously).
The alarm subscribe gated on 'a handle exists', which is correct for an idempotent
re-push and wrong for a deploy that widens/narrows the set. Combined with the
spawn-time desired set, a respawning deploy could latch the PREVIOUS revision's
alarm refs for the life of the connection; sourceNodeIds-filtering drivers
(OpcUaClient/AbCip/Focas) would never deliver the new alarm.
Seen RED: LastSubscribedAlarmRefs stayed [alarmX] after a deploy widening to
[alarmX, alarmY].
Crash seam: the planned null-Snapshot OnDataChange (no SupervisorStrategy fallback needed).
Seen RED with T6 reverted: InitializeCount 1, not 2 — with a preceding ShutdownCount>=1
assertion proving the restart really happened, so the red is not ambiguous with 'never crashed'.
Seen RED against a T3-reverted build: all 4 failed, Created[1].SubscribeCount == 0
on the headline case. 20x isolation run green after the fix was restored.
Review round on 3e62f161. Two coverage gaps and three wording/comment nits.
IMPORTANT 1 — deregistration is now proven DATA-PRESERVING. The self-heal test
inserted a deployment_pointer row and rebooted unconfigured but never looked at
the row again, so a library regression that touched base-table data during
cleanup would have gone unnoticed — on the very tables that ARE the
boot-from-cache backstop, and on the default-OFF nodes least likely to notice.
The new DisablingReplication_PrunesBookkeepingButNeverTouchesTheCachedDataItself
asserts the row's CONTENT survives (not just its count — a count passes against
a cleanup that blanks columns) while __localdb_row_version and __localdb_oplog,
the bookkeeping deregistration does own, go to zero.
IMPORTANT 2 — mid-loop partial failure is documented and pinned. Both loops flip
four tables with no try/catch, so a throw on the third leaves two flipped and
propagates out of the AddZbLocalDb singleton factory, failing host start. That
is correct — a node that came up anyway would be silently capturing on an
arbitrary subset — and both library calls are idempotent, so the retried boot
completes the flip. Written into OnReady's remarks and pinned by
AFailureMidwayThroughRegistration_FailsBootLoudly_AndTheRetriedBootConverges,
which drives OnReady through a delegating ILocalDb that throws on the Nth
RegisterReplicated, asserts the throw propagates, asserts the wrapper actually
reached that call, then re-runs OnReady unwrapped and asserts all four converge.
MINOR 3 — the Boot helper now records that OnReady's null-logger fallback lands
on Serilog's static Log.Logger, which this assembly never assigns; assertions
about logging pass an explicit logger.
MINOR 5 — log wording: "are both unset" -> "are both absent — unset or blank",
matching IsNullOrWhiteSpace.
MINOR 4 — LocalDbDeploymentArtifactCacheTests said its setup "mirrors
LocalDbSetup.OnReady"; it reproduces the two tables only and registers them
unconditionally without baselining. Softened to say so and to name the
divergence as intentional and inert there.
Falsified both new pins. Wrapper set to failOnCall: 99 (never throws) => the
partial-flip pin is the SOLE failure, so it genuinely exercises the Nth-call
throw path rather than some incidental exception. Predicate forced constant-true
=> five pins red including the new data-preservation one. Both mutations
reverted.
LocalDbSetupTests 15/15. Host.IntegrationTests 226 passed / 0 failed / 5
skipped. Runtime.Tests LocalDbDeploymentArtifactCacheTests 12/12.
The batched ingest's append-failure catch had zero coverage, and two doc
statements overstated the loss: the Warning said the burst's values were
"dropped", and RecorderStatus.OutboxAppendFailures said "the value was
dropped, not recorded". The outbox contract is prefix-never-orphan, so a
partial-prefix failure leaves entries durably queued that drain normally.
- New test pins the branch: one 3-item burst whose group commit commits a
1-entry prefix then throws => OutboxAppendFailures == 1 (per burst, not
per value), TotalRecorded == 0, actor alive, and the prefix still reaches
the writer via the post-failure DrainTick (drainInterval 30s, so the
steady cadence cannot account for it). Falsified twice: counting per item
and dropping the drain nudge each turn it red.
- Second test pins the OperationCanceledException filter from its
observable side - a cancel that is NOT shutdown is metered, not swallowed.
Removing the 'when (_lifetime.IsCancellationRequested)' turns it red. The
shutdown side has no cheap seam (the counter dies with the actor).
- Docs corrected: OutboxAppendFailures counts FAILED BATCH APPENDS, one per
burst whatever its size (a granularity change from the per-value era), and
is not a count of values lost; TotalRecorded under-counts when a commit
fails after a partial prefix. Log message says "failed to append" and
names the prefix. No functional change beyond the message string.
Also folds in the DrainBatchSize default alignment behind 0298a0b9: the
recorder's two ctor defaults and its non-positive fallback still said 64
while ContinuousHistorizationOptions.DrainBatchSize now defaults to 1024.
No test pinned the old 64.
C1 — a non-rebuild apply reporting failedNodes > 0 no longer advances _lastApplied.
Pre-delta-materialisation the full passes re-ensured every node on every apply, which
silently repaired any prior swallowed sink fault. The delta path removed that accidental
self-healing: a failed node sat inside _lastApplied, never appeared in a diff set again,
and EnsureVariable early-returns on the ones that landed — so it was lost until an
unrelated change forced a rebuild. The advance also moved to AFTER the materialise
passes, so a throwing pass leaves _lastApplied at the previous composition too. A
rebuild still advances even with failures (the ratchet is its resync path).
I2 — a UnsReferenceDelta whose identity is unchanged (same NodeId, EquipmentId and
BackingRawPath) is now applied in place via UpdateTagAttributes(Uns) instead of
remove+recreate, so the mirror's MonitoredItems survive an operator historizing or
reshaping the raw tag behind them. Remove+recreate stays for identity-changing deltas
(re-point, effective-name edit).
I3 — RemoveVariableNode severs the inverse half of every outgoing Organizes edge, the
variable-node counterpart of UnwireAlarmNotifiers. Rebuilds used to sweep these up;
surgical applies made rebuilds rare, so they accumulated on the raw node for the life of
the process.
I5 — added UNS reference variables are announced (their equipment folder is the parent,
already the Uns realm). Raw adds still are not; the gap comment now says so honestly
rather than calling it neutral and pre-existing.
I4 + M1 — corrected two comments that no longer described the code: the "re-point →
rebuild" claim in ApplyPureRemove, and the "N lock acquisitions" rationale for the delta
passes (Ensure* early-return on a dictionary probe before the lock).
Adversarial review of 9f68f272 (classifier: non-alarm raw-tag deltas became
surgical) found stale UNS inheritance after a surgical raw edit. Editing a raw
tag's IsHistorized / HistorianTagname / IsArray / ArrayLength left every
referencing UNS node STALE: none of those fields were on UnsReferenceVariable,
so no coincident UnsReferenceDelta fired; the applier updated the raw node in
place; and EnsureVariable early-returns on an existing node. Consequences:
HistoryRead through the UNS NodeId served a different series than through the
raw NodeId (breaking the documented dual-registration invariant), a
de-historized tag kept serving history via UNS, and a scalar->array flip left
the UNS mirror scalar AND writable (bypassing the array read-only write gate).
UnsReferenceVariable now carries Backing{IsHistorized,HistorianTagname,IsArray,
ArrayLength}, copied from the backing tag's TagConfigIntent at compose time, so
record equality makes the reference Changed in the SAME plan. Both deltas are
non-rebuild kinds, so the existing machinery repairs the mirror surgically:
remove-previous in Apply, recreate in MaterialiseUnsReferences. That pass now
reads the four values from the RECORD (the single truth the planner diffed)
instead of a rawByPath back-lookup, preserving historian resolution exactly
(blank override => BackingRawPath, which is the backing tag's NodeId).
The artifact-decode seam needs no change: DeploymentArtifact.BuildRawAndUnsSubtrees
drives AddressSpaceComposer.Compose verbatim, which is what guarantees byte-parity.
The classifier needs no change either (a UnsReferenceDelta never forces Rebuild);
its comment now records why.
Also from the same review: a three-place-contract comment on RawTagPlan's
hand-written Equals naming its two downstream consumers, plus classifier pins for
the .Any(!eligible) quantifier, an ArrayLength-only delta, and an
alarm-content-only delta.
ConfigComposer gzips the serialised snapshot (CompressionLevel.Fastest)
immediately after SerializeToUtf8Bytes and BEFORE taking the SHA-256, so
the compressed bytes ARE the artifact everywhere: Deployment.ArtifactBlob,
the LocalDb cache chunks, the gRPC fetch stream, and the RevisionHash a
FetchAndCache node verifies against. The invariant the deploy path rests on
— RevisionHash == SHA-256(stored/wire bytes) — is preserved, which is what
leaves the fetcher, the cache and the serve path untouched: nothing between
the composer and DeploymentArtifact.Open ever looks inside the blob.
Read side: Open() sniffs the gzip magic 1F 8B (valid JSON can never start
with 0x1F, so no framing of our own is needed) and inflates through a size
guard — MaxDecompressedBytes, 512 MiB, internal + mutable so the guard can
be exercised without inflating half a gigabyte per test run. Pre-upgrade
uncompressed blobs take the identical path they always did.
Every decompression failure — corrupt stream, truncated stream, over-limit
inflation — is reported as JsonException, the same exception family the
malformed-JSON path already owns. So the lenient static wrappers still
degrade to empty results and the apply paths still fail the apply and keep
last-known-good (#485); no caller's decision changes because the reason the
bytes are unusable changed.
gzip output is not guaranteed byte-stable across .NET releases. Harmless
here: the hash is computed FROM the emitted bytes at compose time and never
re-derived from the JSON, so the worst an implementation change costs is
one spurious "changed" revision after a runtime upgrade. Snapshot
determinism is unaffected — compression wraps the final bytes and reorders
nothing.
Tests: gzip/uncompressed parity through both the instance parses and the
statics, corrupt-gzip leniency through the wrappers, the size guard (with a
falsifiability control proving the same bytes inflate fine under the
production limit), and composer-side blob-starts-with-1F8B +
RevisionHash == SHA256(blob) with a control proving the hash is NOT over
the JSON.
Every public entry point on DeploymentArtifact took ReadOnlySpan<byte> and did
JsonDocument.Parse(blob.ToArray()) — a full copy plus a full document build per
call — so one apply paid ~8-11 full parses of the same bytes (the scoped
ParseComposition alone parsed three times: scope, composition, BuildClusterSets).
DeploymentArtifact.Open(byte[]) now parses once into ParsedDeploymentArtifact,
which owns the JsonDocument and exposes an instance method mirroring each static
entry point. The moved bodies operate on Root; BuildClusterSets takes JsonElement
instead of re-parsing the blob; ResolveClusterScope is memoized per node id, since
every consumer of one apply asks about the same node.
Every static is now a thin wrapper (Open + delegate + dispose) keeping its
ReadOnlySpan<byte> signature and its lenient empty/malformed contract — the
wrapper pays the one copy and owns the JsonException catch, so output shapes are
unchanged. Hot callers migrate to Open() separately.
ParsedDeploymentArtifactTests pins same-bytes-same-output through both doors for
all six entry points over a rich multi-cluster artifact (raw chain + UNS refs +
scripts + keys + ACLs), with falsifiability controls proving the fixture actually
scopes, plus memoization and after-dispose-use coverage.
Accumulated fast-follows from the Task 1-11 reviews. No behaviour change on the
value path.
- Strengthen OpcUaPublishActorBatchTests.Sink_throw_is_swallowed_and_logged. The
survival assertion alone did NOT prove the catch exists: Akka's default
supervision RESTARTS a throwing actor and the restart preserves the mailbox, so
the follow-up message landed either way and the test passed against a build with
no catch at all. It now asserts via EventFilter that the exception NEVER reaches
supervision (Expect(0) on the InvalidOperationException) and that the handler's
own Warning IS logged, keeping the survival assertion. Everything that must have
happened goes inside the Expect(0) action — it counts matches at the end of the
action, so an assertion left outside would race the actor and pass vacuously.
Verified falsifiable: deleting the catch turns the test red.
- MapKey(NodeId): the non-string identifier branch collapsed to a string.Empty key
silently. Such a key cannot match anything the manager stored, so the caller sees
an unexplained miss rather than an error. It now logs a Utils.LogWarning naming
the seam. Every current call site is provably string-only, so this should never
fire.
- The two WireAlarmNotifiers Utils.LogInfo sites interpolated the RealmKey struct,
rendering a raw struct dump. Interpolate .Id and .Realm as separate placeholders
so log-grep patterns stay consistent with the file's other sites.
- Stale comments: the _eventNotifierSources key is a RealmKey now, not a
namespace-qualified NodeId string; and three comments still named
DriverHostActor.ForwardToMux, which Task 8 replaced with ForwardBatchToMux.
DependencyMuxActor now receives DriverInstanceActor.AttributeValueBatchPublished — the
primary value ingress since DriverHostActor's batched fan-out — and filters it per item,
emitting one DependencyValueChanged per genuinely interested (item, subscriber) pair with
that item's own value/timestamp/status sub-code (#519).
The per-item AttributeValuePublished receive stays: DriverHostActor's comms-loss fan
fabricates it, and per-tag drivers still take that path. Indexed for-loop over Items to
avoid an interface-enumerator allocation per burst.
Replaces the temporary per-item unwrap bridge with a real batched handler: one
AttributeValueBatchPublished burst now costs ONE hop to the dependency mux and ONE
OpcUaPublishActor.AttributeValueBatchUpdate, instead of one message per value.
Routing per item is unchanged — the v3 Batch 4 single-source fan-out (raw NodeId +
every referencing UNS NodeId, identical value/status/timestamp), with an unmapped ref
Debug-logged and dropped without disturbing the rest of the burst. A burst in which
nothing resolves sends no publish message at all rather than an empty batch.
Indexed for-loop over Items is deliberate: no interface-enumerator allocation per
burst on the hottest routing seam. ForwardToMux and its registrations stay for the
comms-loss fan and per-tag drivers.
Joseph Doherty