fix(rust_brain): preserve HLC on snapshot restore and gossip replay - #70
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v0.6.0 added HybridLogicalClock enforcement but restore_from_file(), bulk_write(), and gossip.receive() did not round-trip HLC timestamps. After disaster-recovery restore, nodes received fresh HLC values, causing TimestampRegression on valid causal successor writes and silent rejection of gossiped updates. - Add _parse_hlc() for snapshot/wire normalisation with legacy fallback - restore_from_file: restore hlc, update global clock, hold lock - bulk_write: pass hlc from row payloads - gossip.receive: apply hlc, reject stale overwrites, skip missing-hlc updates - 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
v0.6.0 added Hybrid Logical Clock (HLC) monotonic enforcement, but
restore_from_file(),bulk_write(), andgossip.receive()did not round-trip HLC timestamps.Concrete trigger: After disaster-recovery snapshot restore, restored nodes received fresh HLC values instead of their snapshot HLCs. Valid causal successor writes (e.g.
hlc=(5000, 11, "nodeA")after restore of(5000, 10, "nodeA")) raisedTimestampRegressionand were rejected — silent data loss in replication/gossip paths.Root cause
restore_from_file()createdMemoryNodewithout passinghlc, defaulting to_hlc.now()bulk_write()omittedhlcfrom row payloadsgossip.receive()did not passhlc/ts_nsand could not reject stale overwritesFix
_parse_hlc()for snapshot/wire normalisation with legacy fallbackrestore_from_file: restore HLC, update global clock, hold lock during mutationbulk_write: passhlcfrom row payloadsgossip.receive: apply HLC, reject stale overwrites, skip missing-HLC updates on existing keysValidation
pytest tests/test_enterprise_backup.py tests/test_gossip.py tests/test_rust_brain.py— 27 passed