Files
meshcore-analyzer/cmd/server/bridge_handle_nodes_test.go
Kpa-clawbot 8bf7709970 feat(repeater): usefulness score — bridge axis (#672 axis 2 of 4) (#1275)
RED test commit: `fd661569` — CI will fail on this (stub returns empty
map; assertions fail by design). GREEN: `bf4b8592`.

## What

Implements **axis 2 of 4** for the repeater usefulness score per #672
([status
comment](https://github.com/Kpa-clawbot/CoreScope/issues/672#issuecomment-4484635378)).
The Bridge axis measures *structural importance*: how many shortest
paths between other nodes route through this one. A high-traffic
redundant node and a low-traffic critical bridge will no longer look
identical.

## Algorithm

**Brandes' weighted betweenness centrality** with Dijkstra for shortest
paths (`cmd/server/bridge_score.go`).

- Nodes: pubkeys in the `neighbor_edges` graph
- Edge weight: `Score(now) * Confidence()` — per the convention from
#1235 (count + recency decay scaled by observer-diversity confidence).
Geo-rejected edges already excluded at graph build time (#1230) so we
don't re-filter here.
- Dijkstra distance: `1 / max(epsilon, weight)` — high affinity = cheap
cost.
- Normalize: divide by max observed centrality so output is in `[0, 1]`.

Cost: `O(V · (E + V log V))`. Staging-scale (~600 nodes / ~2 000 edges)
≈ ~4.8M ops, completes in milliseconds.

## Where it lives

- `cmd/server/bridge_score.go` — pure algorithm, no locks
- `cmd/server/bridge_recomputer.go` — background recomputer (mirrors
#1240/#1262 pattern), 5-min default interval, initial sync prewarm,
snapshot stored in `s.bridgeScoreMap atomic.Pointer[map[string]float64]`
- `cmd/server/routes.go` — `handleNodes` adds `node["bridge_score"]` on
repeater/room rows; node-detail handler adds it on the single-node path
- `public/nodes.js` — separate **Bridge** row in the node detail panel,
alongside the existing **Usefulness** (Traffic) row. Distinct
colour-coded bar.

## What's NOT in this PR (still pending for #672)

- **Coverage axis** (axis 3) — unique observer-pair connectivity
- **Redundancy axis** (axis 4) — simulated node-removal impact
- **Composite** — once all 4 axes ship, swap the `usefulness_score`
formula from "traffic-only" to the weighted composite

`Refs #672` (not `Fixes` — issue stays open until all 4 axes + composite
ship).

## Tests

- `TestComputeBridgeScores_LineGraph` — 4-node line: middles non-zero,
leaves zero, max normalized to 1.0
- `TestComputeBridgeScores_TriangleNoBridge` — clique has zero bridges
- `TestComputeBridgeScores_Empty` — defensive nil-safety
- `TestComputeBridgeScores_WeightSensitive` — mutation guard: revert the
`1/w` inversion and this test fails
- `TestBridgeScore_HandleNodesSurface` — integration: `/api/nodes`
returns `bridge_score` on repeater rows; middle nodes > 0, ends == 0

---------

Co-authored-by: clawbot <bot@meshcore.local>
2026-05-18 22:51:23 -07:00

124 lines
4.0 KiB
Go

package main
import (
"encoding/json"
"net/http/httptest"
"testing"
"time"
"github.com/gorilla/mux"
)
// TestBridgeScore_HandleNodesSurface verifies that /api/nodes
// includes a `bridge_score` field on repeater rows after the bridge
// recomputer has run. Drives the line-graph A-B-C-D through the full
// pipeline: insert nodes, populate the neighbor graph, force a
// recompute, hit the handler, parse the response. Issue #672 axis 2.
func TestBridgeScore_HandleNodesSurface(t *testing.T) {
db := setupCapabilityTestDB(t)
defer db.conn.Close()
// handleNodes/db.GetNodes selects a foreign_advert column not in
// the minimal capability-test schema.
if _, err := db.conn.Exec(`ALTER TABLE nodes ADD COLUMN foreign_advert INTEGER DEFAULT 0`); err != nil {
t.Fatal(err)
}
// Four repeater nodes in a line.
pks := []string{
"aaaa000000000000000000000000000000000000000000000000000000000000",
"bbbb000000000000000000000000000000000000000000000000000000000000",
"cccc000000000000000000000000000000000000000000000000000000000000",
"dddd000000000000000000000000000000000000000000000000000000000000",
}
recent := time.Now().UTC().Format("2006-01-02T15:04:05.000Z")
for _, pk := range pks {
if _, err := db.conn.Exec(`INSERT INTO nodes
(public_key, name, role, lat, lon, last_seen, first_seen, advert_count)
VALUES (?, ?, 'repeater', 37.5, -122.0, ?, ?, 10)`,
pk, "node-"+pk[:4], recent, recent); err != nil {
t.Fatal(err)
}
}
store := NewPacketStore(db, nil)
// Build neighbor graph with the line A-B-C-D. Add each edge
// `count` times so its time-decayed Score saturates.
g := NewNeighborGraph()
now := time.Now()
obs := "obs-test"
snr := 5.0
for i := 0; i < 10; i++ {
g.upsertEdge(pks[0], pks[1], "aa", obs, &snr, now)
g.upsertEdge(pks[1], pks[2], "bb", obs, &snr, now)
g.upsertEdge(pks[2], pks[3], "cc", obs, &snr, now)
}
store.graph.Store(g)
// Direct invocation of the recomputer's compute path — bypassing
// StartBridgeScoreRecomputer's package-level once-flag (which is
// problematic across tests).
recomputeBridgeScoresSafe(store)
snap := store.GetBridgeScoreMap()
if len(snap) == 0 {
t.Fatalf("expected non-empty bridge score snapshot, got empty")
}
// Sanity: middle nodes b/c must be positive, ends must be zero.
if snap[pks[1]] <= 0 || snap[pks[2]] <= 0 {
t.Errorf("middle nodes should have positive bridge: b=%v c=%v",
snap[pks[1]], snap[pks[2]])
}
if snap[pks[0]] != 0 || snap[pks[3]] != 0 {
t.Errorf("end nodes should have zero bridge: a=%v d=%v",
snap[pks[0]], snap[pks[3]])
}
// Wire a Server, call handleNodes, parse the response.
cfg := &Config{Port: 3000}
hub := NewHub()
srv := NewServer(db, cfg, hub)
srv.store = store
router := mux.NewRouter()
srv.RegisterRoutes(router)
req := httptest.NewRequest("GET", "/api/nodes?limit=100", nil)
rr := httptest.NewRecorder()
router.ServeHTTP(rr, req)
if rr.Code != 200 {
t.Fatalf("handleNodes status: want 200, got %d body=%s", rr.Code, rr.Body.String())
}
var resp struct {
Nodes []map[string]interface{} `json:"nodes"`
}
if err := json.Unmarshal(rr.Body.Bytes(), &resp); err != nil {
t.Fatalf("decode: %v body=%s", err, rr.Body.String())
}
gotBy := map[string]map[string]interface{}{}
for _, n := range resp.Nodes {
if pk, _ := n["public_key"].(string); pk != "" {
gotBy[pk] = n
}
}
for _, pk := range pks {
n, ok := gotBy[pk]
if !ok {
t.Errorf("node %s missing from response", pk[:4])
continue
}
if _, has := n["bridge_score"]; !has {
t.Errorf("node %s: bridge_score field absent from response", pk[:4])
}
}
// Middle node B must report a non-zero bridge_score; end node A
// must report exactly zero. These two assertions together prevent
// a "field present but always 0" regression.
if v, _ := gotBy[pks[1]]["bridge_score"].(float64); v <= 0 {
t.Errorf("middle node B bridge_score in API response should be > 0, got %v", v)
}
if v, _ := gotBy[pks[0]]["bridge_score"].(float64); v != 0 {
t.Errorf("end node A bridge_score in API response should be 0, got %v", v)
}
}