fix(rust_brain): preserve HLC on snapshot restore and gossip replay - #76
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restore_from_file() assigned fresh HLC timestamps instead of reading them from the snapshot, causing causally valid writes (gossip replay, bulk_write, post-restore updates) to raise TimestampRegression and silently drop data. Also fix bulk_write and gossip.receive() to round-trip HLC timestamps. Co-authored-by: Daniel <DJLougen@users.noreply.github.com>
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Bug and impact
restore_from_file()assigned fresh HLC timestamps instead of reading them from the snapshot. After disaster-recovery restore, causally valid writes (gossip replay,bulk_write, post-restore updates) raisedTimestampRegressionand were silently dropped — data loss in distributed deployments.Root cause
HLC timestamps were added in v0.6.0 and serialized in snapshots, but restore/gossip/bulk_write paths never parsed or applied them. Restored nodes got fresh wall-clock HLCs that were always "newer" than legitimate causal successors from peers.
Fix
_parse_hlc()helper for snapshot/wire normalizationrestore_from_file(): restore HLC per node, update global HLC, hold lock during restorebulk_write(): pass through HLC from row payloadsgossip.receive(): apply HLC, reject stale updates, skip HLC-less overwrites on existing keysValidation
TimestampRegressiontest_hlc_snapshot_gossip.py,test_enterprise_backup.py,test_gossip.py,test_rust_brain.py