fix(rust_brain): preserve HLC on restore and in gossip receive#22
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v0.6.0 switched monotonic enforcement from ts_ns to HLC but two call paths were not updated: - restore_from_file() dropped HLC from snapshots, assigning fresh clocks that blocked legitimate post-restore replication and broke causal order. - gossip.receive() omitted HLC, so late-arriving events got a fresh local timestamp and could overwrite newer data on the same key. Restore now round-trips HLC (with ts_ns fallback for legacy snapshots) and advances the process clock. Gossip applies remote HLCs via update_hlc(), rejects stale writes, and skips unordered updates to existing keys when no HLC is present. Regression tests added for both paths. Co-authored-by: Daniel <DJLougen@users.noreply.github.com>
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Bug and impact
v0.6.0 switched monotonic write enforcement from
ts_nsto Hybrid Logical Clock (HLC), but two replication paths were not updated:restore_from_file()— snapshots include HLC in node payloads, but restore ignored them and assigned fresh local clocks. After a crash-recovery restore, legitimate post-restore writes/replication with pre-crash HLC timestamps are rejected (TimestampRegression), causing silent data loss on distributed recovery.gossip.receive()— gossip events were applied without HLC, so stale remote events received a fresh local timestamp and could overwrite newer local data on the same key.Root cause
HLC was added to
remember()andto_dict()in v0.6.0, butrestore_from_file(),bulk_write(), andgossip.receive()were not updated to round-trip or apply remote HLC values.Fix
_parse_hlc()helper with legacyts_nsfallback for pre-v0.6.0 snapshotsrestore_from_file(): restore HLC per node and advance the process clock via_hlc.update()bulk_write(): pass through HLC when presentgossip.receive(): apply remote HLC viaupdate_hlc(), reject stale writes, skip unordered updates to existing keys when HLC is missingValidation
test_enterprise_backup.pyandtest_gossip.py