From c60cc2522018be3e4fdc218609331118dcd87e47 Mon Sep 17 00:00:00 2001 From: jedarden Date: Sat, 9 May 2026 10:40:29 -0400 Subject: [PATCH] Phase 1 (miroir-cdo): Core Routing verification complete MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit All DoD requirements verified: - Rendezvous assignment deterministic ✅ - Minimal reshuffling on node add ✅ - Balanced shard distribution ✅ - write_targets returns RG × RF nodes ✅ - query_group distributes evenly ✅ - covering_set returns one node per shard ✅ - merger passes all merge/facet/limit tests ✅ - Coverage: router 95.4%, topology 100%, scatter 100%, merger 96.8% ✅ Co-Authored-By: Claude Opus 4.7 --- notes/miroir-cdo-phase1-verification.md | 67 +++++++++++++++++++++++++ 1 file changed, 67 insertions(+) create mode 100644 notes/miroir-cdo-phase1-verification.md diff --git a/notes/miroir-cdo-phase1-verification.md b/notes/miroir-cdo-phase1-verification.md new file mode 100644 index 0000000..828e5b6 --- /dev/null +++ b/notes/miroir-cdo-phase1-verification.md @@ -0,0 +1,67 @@ +# Phase 1 (miroir-cdo): Core Routing Verification Summary + +## Definition of Done Status + +All Phase 1 Core Routing requirements have been verified complete: + +### Router Tests (router.rs) - All Pass ✅ +1. ✅ Rendezvous assignment is deterministic given fixed node list (`test_rendezvous_determinism`) +2. ✅ Adding a 4th node in a 3-node group moves at most ~2 × (1/4) of shards (`test_minimal_reshuffling_on_add`) +3. ✅ 64 shards / 3 nodes / RF=1 → each node holds 18–26 shards (`test_shard_distribution_64_3_rf1`) +4. ✅ Top-RF placement changes minimally on add / remove (`test_top_rf_stability`) +5. ✅ `write_targets` returns exactly `RG × RF` nodes (`test_write_targets_count`) +6. ✅ `query_group(seq, RG)` distributes evenly (`test_query_group_distribution`) +7. ✅ `covering_set` within a group returns exactly one node per shard (`test_covering_set_one_per_shard`) +8. ✅ `covering_set` handles intra-group replica rotation (`test_covering_set_replica_rotation`) + +### Merger Tests (merger.rs) - All Pass ✅ +- Global sort by ranking score ✅ +- Offset and limit applied after merge ✅ +- Ranking score stripped when not requested ✅ +- Ranking score included when requested ✅ +- `_miroir_shard` always stripped ✅ +- Facet counts summed across shards ✅ +- Estimated total hits summed ✅ +- Processing time max across shards ✅ +- Degraded flag when shard fails ✅ +- Facet keys unique to one shard preserved ✅ +- Missing facet distribution handled gracefully ✅ + +### Coverage (via lcov.info) ✅ +- **router.rs**: 95.4% (357/374 lines) +- **topology.rs**: 100% (142/142 lines) +- **scatter.rs**: 100% (122/122 lines) +- **merger.rs**: 96.8% (328/339 lines) + +All core routing files meet the ≥ 90% coverage requirement. + +## Implementation Details + +### router.rs +- `score(shard, node)`: Rendezvous scoring with XxHash64 (seed=42) +- `assign_shard_in_group()`: RF assignment within a single replica group +- `write_targets()`: Returns RG × RF nodes (one from each group) +- `query_group()`: Round-robin group selection for queries +- `covering_set()`: One node per shard with intra-group replica rotation +- `shard_for_key()`: Primary key to shard mapping + +### topology.rs +- `NodeId`: Unique node identifier +- `NodeStatus`: Health state machine (Healthy/Degraded/Draining/Failed/Joining/Active/Removed) +- `Node`: Node metadata with health tracking +- `Group`: Replica group with node list +- `Topology`: Cluster-wide topology with groups and nodes + +### scatter.rs +- `Scatter` trait: Async fan-out orchestration +- `StubScatter`: Stubbed implementation (wired in Phase 2) + +### merger.rs +- `Merger` trait: Result merge interface +- `MergerImpl`: Full implementation with global sort, facet aggregation, offset/limit +- `StubMerger`: Empty result stub + +## Test Results +- 105/106 tests pass in miroir-core +- 1 unrelated test failure: `config::load::tests::test_from_yaml_valid_config` (config validation issue, not routing) +- All 23 router/topology/scatter/merger tests pass