fix(rust_brain): preserve HLC on snapshot restore and gossip receive#49
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After snapshot restore, nodes were assigned fresh HLC timestamps instead of the stored values from the snapshot. Post-restore causal writes with legitimate successor HLCs were rejected as TimestampRegression, causing silent data loss in disaster-recovery and multi-node gossip scenarios. - Add _parse_hlc() for snapshot/wire HLC normalisation - Restore HLC on snapshot load and advance global _hlc - Pass HLC through bulk_write and gossip receive - Reject stale gossip updates; skip HLC-less updates on existing keys - Add regression tests for restore round-trip and gossip ordering Co-authored-by: Daniel <DJLougen@users.noreply.github.com>
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Bug and impact
After snapshot restore,
restore_from_file()assigned fresh HLC timestamps instead of the values stored in the snapshot. Legitimate post-restore causal writes (and gossip replays with proper HLC ordering) were rejected asTimestampRegression, causing silent data loss in disaster-recovery and multi-node gossip scenarios.Concrete trigger:
remember("k", "v1", hlc=(5000, 10, "nodeA"))remember("k", "v2", hlc=(5000, 11, "nodeA"))→ rejected because restored node got a fresh wall-clock HLC far larger than the legitimate successorRoot cause
restore_from_file()constructedMemoryNodewithout passinghlc, so each restored node received a new_hlc.now()value.gossip.receive()andbulk_write()also ignored HLC fields on incoming events.Fix
_parse_hlc()for snapshot/wire HLC normalisation (with legacy fallback fromts_ns)_hlcbulk_writeandgossip.receiveValidation