fix(rust_brain): preserve HLC on snapshot restore and gossip replay - #60
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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 on writes, but three replication paths did not round-trip HLC timestamps:
restore_from_file()— restored nodes received fresh HLC values instead of snapshot valuesbulk_write()— ignoredhlcfield in row payloadsgossip.receive()— ignoredhlc/ts_nson incoming eventsImpact: After disaster-recovery snapshot restore, valid causal successor writes and gossip replays are rejected with
TimestampRegression, causing silent data loss in distributed deployments.Root cause
HLC enforcement was added to
remember()in v0.6.0, but snapshot restore, bulk import, and gossip apply paths were not updated to preserve or apply stored HLC values.Fix
_parse_hlc()helper for snapshot/wire normalisation (with legacy fallback for pre-v0.6.0 snapshots)restore_from_file(): restorehlc, call_hlc.update()per node, hold_lockduring restorebulk_write(): passhlcfrom row payloadsgossip.receive(): applyhlc/ts_ns, reject stale overwrites, skip missing-HLC updates on existing keysValidation
(wall, 0, uuid)instead of(5000, 10, nodeA); causal write failedtest_enterprise_backup.pyandtest_gossip.py