fix(rust_brain): preserve HLC on snapshot restore and gossip receive#54
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restore_from_file() dropped HLC timestamps from snapshots, assigning fresh HLCs instead. After disaster recovery, causal successor writes from the original writer raised TimestampRegression — silent data loss on replication. - Add _parse_hlc() for snapshot/wire normalisation with legacy fallback - restore_from_file: restore node HLC and advance global clock via _hlc.update() - bulk_write: pass through hlc from row payloads - gossip.receive: forward HLC/ts_ns, update clock, skip stale/missing HLC - Lock restore mutation under self._lock for thread safety Regression tests for snapshot round-trip and gossip HLC ordering. Co-authored-by: Daniel <DJLougen@users.noreply.github.com>
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Bug and impact
restore_from_file()dropped Hybrid Logical Clock (HLC) timestamps from snapshots, assigning fresh HLCs instead. After disaster recovery, causal successor writes from the original writer raisedTimestampRegression— silent data loss on replication and gossip sync.Trigger scenario: Node writes memory with
hlc=(5000, 10, "nodeA"), snapshots to disk, crashes, restores. A causal successor writehlc=(5000, 11, "nodeA")is rejected because restore assigned a fresh HLC(wall, 0, uuid).Root cause
v0.6.0 added HLC enforcement to
remember()butrestore_from_file()andgossip.receive()were not updated to preserve/forward HLC timestamps.Fix
_parse_hlc()for snapshot/wire normalisation with legacy fallbackrestore_from_file: restore node HLC and advance global clock via_hlc.update()bulk_write: pass throughhlcfrom row payloadsgossip.receive: forward HLC/ts_ns, update clock, skip stale/missing HLCself._lockfor thread safetyValidation