fix(rust_brain): preserve HLC on snapshot restore and gossip receive#41
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restore_from_file() was creating MemoryNode without the snapshot HLC, assigning fresh timestamps. Post-restore causal writes with pre-crash HLC were rejected (TimestampRegression), causing silent data loss after DR. gossip.receive() also ignored HLC, allowing stale remote events to overwrite fresher local state or skip ordering entirely. - Add _parse_hlc() for snapshot/wire normalisation - Restore HLC and advance global clock on snapshot load - Pass HLC through bulk_write, gossip receive with stale rejection - Hold lock during restore and gc_expired - 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
restore_from_file()andgossip.receive()did not preserve or apply Hybrid Logical Clock (HLC) timestamps introduced in v0.6.0.Snapshot restore: After disaster recovery, restored nodes received fresh HLC timestamps instead of their snapshot values. Subsequent causal writes using pre-crash HLC values were rejected with
TimestampRegression, causing silent data loss on the first post-restore write.Gossip sync: Remote events without HLC could overwrite fresher local state, or stale gossip with lower HLC could clobber newer data in distributed deployments.
Root cause
restore_from_file()constructedMemoryNodewithout thehlcfield, defaulting to_hlc.now()gossip.receive()calledremember()without passinghlc,ts_ns, oredgesbulk_write()also dropped HLC from row payloadsFix
_parse_hlc()to normalise HLC from snapshot/wire form (list/tuple) with legacy fallback fromts_ns_hlc.update()restore_from_file()andgc_expired()Validation
pytest tests/test_enterprise_backup.py tests/test_gossip.py tests/test_rust_brain.py— 28 passedtest_restore_preserves_hlc_for_replication, gossip HLC ordering tests