fix(rust_brain): preserve HLC timestamps on snapshot restore#52
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restore_from_file() dropped HLC values from snapshots, assigning fresh timestamps instead. After restore, causal successor writes and gossip replays with pre-crash HLCs were rejected with TimestampRegression, causing silent data loss in disaster-recovery and multi-node sync paths. - Add _parse_hlc() for wire/snapshot normalisation - Restore HLC per node and advance global HLC on restore - Pass HLC through bulk_write and gossip.receive() - Reject stale gossip overwrites; skip missing-HLC updates on existing keys Co-authored-by: Daniel <DJLougen@users.noreply.github.com>
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Bug and impact
restore_from_file()dropped HLC timestamps from snapshots, assigning fresh wall-clock HLCs instead. After disaster-recovery restore, causal successor writes and gossip replays with pre-crash HLCs were rejected withTimestampRegression, causing silent data loss in backup/restore and multi-node sync paths.Concrete trigger: Node writes memory with
hlc=(5000, 10, "nodeA"), snapshots to disk, restores after crash. A legitimate successor writehlc=(5000, 11, "nodeA")is rejected because restore assigned a fresh HLC far in the future.Root cause
v0.6.0 added HLC-based monotonic enforcement, but
restore_from_file()never read thehlcfield from snapshot JSON.gossip.receive()andbulk_write()also omitted HLC passthrough.Fix
_parse_hlc()for wire/snapshot normalisation (with legacy fallback fromts_ns)bulk_write()andgossip.receive()Validation
TimestampRegressiontest_restore_preserves_hlc_for_replicationand gossip HLC tests