fix(rust_brain): preserve HLC timestamps on snapshot restore and gossip - #74
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restore_from_file() assigned fresh HLC values instead of restoring the snapshotted timestamps. After disaster recovery, gossip replays and causal successor writes with pre-crash HLC were rejected with TimestampRegression — silent data loss in distributed deployments. - Add _parse_hlc() for wire/snapshot normalisation - Restore HLC and advance global clock on snapshot restore - Pass HLC through bulk_write() row payloads - Apply HLC in gossip.receive() with stale-update rejection - Hold lock during restore to prevent concurrent mutation Regression tests in test_hlc_snapshot_gossip.py (29 targeted tests pass). Co-authored-by: Daniel <DJLougen@users.noreply.github.com>
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Bug and impact
restore_from_file()assigned fresh HLC timestamps instead of restoring the snapshotted values. After disaster recovery, gossip replays and causal successor writes with pre-crash HLC were rejected withTimestampRegression— silent data loss in distributed deployments.Concrete trigger: Snapshot a node with
hlc=(5000, 10, "nodeA"), restore, then attempt a causal successor write withhlc=(5000, 11, "nodeA"). The write fails because restore assigned a fresh wall-clock HLC far in the future.Root cause
v0.6.0 added HLC-based monotonic ordering, but
restore_from_file(),bulk_write(), andgossip.receive()never preserved or applied HLC timestamps from their payloads.Fix
_parse_hlc()for wire/snapshot normalisation (backward-compatible with pre-v0.6.0 snapshots)bulk_write()row payloadsgossip.receive()with stale-update rejectionValidation
test_hlc_snapshot_gossip.py,test_enterprise_backup.py,test_gossip.py,test_rust_brain.py