fix(rust_brain): preserve HLC timestamps on snapshot restore and gossip - #61
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restore_from_file() assigned fresh HLC timestamps instead of preserving snapshot values, causing TimestampRegression on legitimate post-restore writes and silent gossip data loss. Also pass HLC through bulk_write and gossip.receive() with stale-event rejection. Co-authored-by: Daniel <DJLougen@users.noreply.github.com>
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Bug and impact
restore_from_file()did not preserve Hybrid Logical Clock (HLC) timestamps from snapshots. After disaster-recovery restore, nodes received fresh(wall, 0, uuid)HLCs instead of their saved causal timestamps. Legitimate post-restore writes and gossip replays with pre-crash HLCs raisedTimestampRegressionand were silently dropped — causing data loss in distributed deployments after backup restore.gossip.receive()also ignored incoming HLCs, allowing stale events to overwrite fresher data or rejecting valid causal updates.Root cause
v0.6.0 added HLC-based monotonic ordering but
restore_from_file(),bulk_write(), andgossip.receive()were not updated to preserve/pass HLC values.Fix
_parse_hlc()helper for wire/snapshot normalizationrestore_from_file(): restore HLC from snapshot, update global HLC, hold lock during restorebulk_write(): pass throughhlcfield from rowsgossip.receive(): apply incoming HLC, reject stale updates, skip missing-HLC updates on existing keysValidation
TimestampRegressiontests/test_enterprise_backup.py::test_restore_preserves_hlc_for_replication(new)tests/test_gossip.py: 3 new HLC ordering tests