fix(rust_brain): preserve HLC on snapshot restore and gossip replay - #75
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restore_from_file() assigned fresh HLC timestamps instead of reading them from the snapshot, causing causally valid writes (gossip replay, bulk_write, post-restore updates) to raise TimestampRegression and silently drop data. Also fix bulk_write and gossip.receive() to round-trip HLC timestamps. Co-authored-by: Daniel <DJLougen@users.noreply.github.com>
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Bug and impact
restore_from_file(),bulk_write(), andgossip.receive()did not preserve Hybrid Logical Clock (HLC) timestamps introduced in v0.6.0. After a snapshot restore, the store assigns fresh HLC values instead of the saved ones. Any subsequent write with a causally valid pre-crash HLC (gossip replay, bulk import, or peer sync) raisesTimestampRegressionand is silently dropped — data loss after disaster recovery.Concrete trigger: Snapshot a node with HLC
(5000, 10, "nodeA"), restore, then apply a causally later write with HLC(5000, 11, "nodeA"). The write is rejected because restore assigned a fresh wall-clock HLC.Root cause
restore_from_file()createdMemoryNodewithout reading thehlcfield from the snapshot, defaulting to_hlc.now().bulk_write()did not passhlcfrom row payloads.gossip.receive()did not apply or update HLC on incoming events.Fix
_parse_hlc()helper for wire/snapshot normalization.restore_from_file(): restore stored HLC, update global clock via_hlc.update(), hold lock during mutation.bulk_write(): round-trip HLC from row payloads.gossip.receive(): apply HLC, reject stale updates, skip missing-HLC overwrites on existing keys.Validation
test_hlc_snapshot_gossip.py,test_enterprise_backup.py,test_gossip.py,test_rust_brain.py.