LocalDbSetup.OnReady registered all four replicated tables unconditionally on
every driver node, replicating or not. That was not merely wasteful (an
unreplicated node paid two INSERTs plus a json_object of the whole row inside
every write transaction, for an oplog nothing ever drained) — it made
baselineExistingRows unusable, so enabling replication on a long-running
default-OFF node converged on SUBSEQUENT WRITES ONLY and the rows already in the
file stayed invisible to the peer, silently and forever.
Registration now follows one predicate, LocalDbSetup.ReplicationIsConfigured:
LocalDb:Replication:PeerAddress OR :ApiKey non-blank. The OR is load-bearing —
only the dialling half of a pair sets PeerAddress, so keying on it alone would
strip capture from every passive node and the pair would converge in one
direction only. SyncListenPort deliberately does not join it: the passive
endpoint is fail-closed on the key, so a port with no ApiKey syncs with nobody.
configured => RegisterReplicated(table, baselineExistingRows: true), per
table, in the unchanged load-bearing DDL->register order
unconfigured => DeregisterReplicated(table), an idempotent boot self-heal that
drops the capture triggers an earlier build left behind and
prunes that table's oplog/row-version rows. One Information
line, only when it actually cleaned something.
PAIR SYMMETRY: the sync handshake compares registered-table digests fail-closed,
so flipping either key is a both-nodes-together change — set it on both and
restart both. Documented in CLAUDE.md, docs/Configuration.md and the replication
runbook (which claimed "this repo never calls DeregisterReplicated").
Verified against the pinned LocalDb 0.2.1: RegisterReplicated(string, bool) and
DeregisterReplicated(string) -> bool both exist; baselining seeds
__localdb_row_version at HLC 0 and the deregister return value distinguishes
"cleaned" from "nothing to clean". No pin bump needed.
Tests: LocalDbSetupTests gains pins for both branches (configured via
PeerAddress alone and via ApiKey alone; unconfigured => no tables, zero
triggers; late-enable => an HLC-0 baseline ledger entry; the log line fires once
and only when something was cleaned) — four went red against the old
unconditional code, and all four go red again under a constant-true predicate.
LocalDbWiringTests splits its exact-set pin into a replicating graph and a
default-OFF one. LocalDbPairHarness and AlarmSfLegacyMigratorTests built their
database from LocalDb:Path alone while configuring the replication engine from a
second config — production reads one configuration, so the two are now aligned.
Host.IntegrationTests: 224 passed, 0 failed, 5 skipped.
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.
Joseph Doherty