fix(rust_brain): preserve HLC on snapshot restore and gossip receive#27
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restore_from_file dropped hlc fields added in v0.6.0, assigning fresh timestamps on restore. Post-crash causal writes and gossip replays with pre-crash HLC were rejected (silent data loss), while gossip events without HLC could overwrite fresher data. - Add _parse_hlc() for snapshot/wire normalisation with legacy fallback - restore_from_file: restore hlc and advance global _hlc per node - bulk_write: pass through hlc from row payloads - gossip.receive: apply hlc, reject stale updates, skip missing-hlc overwrites on existing keys - Tests: snapshot HLC round-trip, gossip stale/new/missing-hlc cases Co-authored-by: Daniel <DJLougen@users.noreply.github.com>
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Bug and impact
restore_from_file()andgossip.receive()did not preserve or apply HLC timestamps added in v0.6.0. After a snapshot restore, the store assigned fresh HLC values instead of the saved ones. Any post-crash causal write or gossip replay carrying the pre-crash HLC was rejected withTimestampRegression— silent data loss in disaster-recovery and multi-node replication paths. Conversely, gossip events without HLC could overwrite fresher local data.Concrete trigger: snapshot a node with
hlc=(5000, 10, "nodeA"), restore, then apply the causal successorhlc=(5000, 11, "nodeA")→ rejected because restore assigned a fresh wall-clock HLC.Root cause
v0.6.0 added HLC to
MemoryNodeand monotonic enforcement inremember(), butrestore_from_file()rebuilt nodes without reading thehlcfield from the snapshot JSON, andgossip.receive()did not pass HLC through on writes.Fix
_parse_hlc()for snapshot/wire normalisation with legacy fallback for pre-v0.6.0 snapshotsrestore_from_file: restorehlcper node and advance the global_hlcclockbulk_write: pass throughhlcfrom row payloadsgossip.receive: apply HLC, reject stale updates, skip missing-HLC overwrites on existing keysValidation
TimestampRegression)