fix(rust_brain): restore HLC timestamps from snapshots#20
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restore_from_file() dropped hlc fields added in v0.6.0, assigning fresh timestamps on reload. After restart, gossip/replay writes with pre-crash HLC were rejected (TimestampRegression), causing silent data loss. Also pass hlc through bulk_write when present in row dicts. Co-authored-by: Daniel <DJLougen@users.noreply.github.com>
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Bug and impact
restore_from_file()did not restorehlcfields introduced in v0.6.0. After a restart from snapshot, every node received a fresh Hybrid Logical Clock timestamp instead of its persisted one.Concrete trigger: Agent saves memory via
snapshot_to_file(), restarts, callsrestore_from_file(), then receives gossip/replay events with HLC timestamps from before the crash. Those writes are rejected withTimestampRegression— silent data loss in distributed deployments.Root cause
v0.6.0 added HLC to
MemoryNodeandsnapshot()serialization, butrestore_from_file()was not updated to read thehlcfield. Restored nodes got default-constructed HLC values (current wall clock), making all pre-crash timestamps appear stale.Fix
hlcfrom snapshot JSON inrestore_from_file()_hlc.update()for each restored node so subsequent local writes stay monotonichlcthroughbulk_write()when present in row dictsValidation
test_restore_preserves_hlc_and_accepts_causal_writesintests/test_enterprise_backup.py