fix(nodes): clear a node's position when nodeUpdate sends null

src/api/client.ts

@@ -233,7 +233,7 @@ export function getTraceDetail(tag: string): Promise<TraceDetail> {
 
 export async function getObserver(observerId: string): Promise<Observer> {
   const observer = await request<Observer>(`/observers/${observerId}`);
-  // The server marshals the stored JSON byte slice as base64; decode it, and accept an object once json.RawMessage ships.
+  // Servers before json.RawMessage (and cache entries written by them) send the stored JSON as base64.
   let metadata: unknown = observer.statusMetadata;
   if (typeof metadata === "string") {
     try { metadata = JSON.parse(new TextDecoder().decode(Uint8Array.from(atob(metadata), c => c.charCodeAt(0)))); }

src/features/nodes/node-updates.ts

@@ -18,8 +18,8 @@ export function patchNodeSummary(
   // only name/coords move in practice; nodeType/iatas are near-static, so we drop data.nodeType here
   // and let a reload carry a rare type change rather than keep a numeric-type lookup in sync
   const name = data.name || prev.name;
-  const lat = data.lat ?? prev.lat;
-  const lng = data.lng ?? prev.lng;
+  const lat = data.lat === undefined ? prev.lat : data.lat;
+  const lng = data.lng === undefined ? prev.lng : data.lng;
   const possiblyForeign = data.possiblyForeign === undefined ? prev.possiblyForeign : data.possiblyForeign ?? undefined;
   // a re-advert that re-sends the same values must keep the SAME ref so patchInfinitePages no-ops
   // (otherwise an unchanged node would trigger a full map FeatureCollection rebuild + setData)

src/types/ws.ts

@@ -110,9 +110,9 @@ export interface WsNodeUpdate {
     // Omitted leaves the prior verdict unchanged; null clears an unknown/reset position.
     possiblyForeign?: boolean | null;
     iata: string;
-    // decimal degrees, same as REST /nodes (api/nodes.go serializes *float64 degrees to both)
-    lat?: number;
-    lng?: number;
+    // decimal degrees as in REST /nodes; omitted keeps the prior position, null clears it (explicit 0/0 advert)
+    lat?: number | null;
+    lng?: number | null;
     isObserver: boolean;
     iatas: NodeIATA[];
     defaultScope?: string;

tests/features/nodes/node-updates.test.ts

@@ -68,6 +68,19 @@ describe("patchNodeSummary", () => {
     expect(out[0]!.lng).toBe(20);
   });
 
+  it("clears the position when the update sends explicit null", () => {
+    const list = [node({ id: "a", lat: 10, lng: 20 })];
+    const out = patchNodeSummary(list, update({ nodeId: "a", lat: null, lng: null }))!;
+    expect(out).not.toBe(list);
+    expect(out[0]!.lat).toBeNull();
+    expect(out[0]!.lng).toBeNull();
+  });
+
+  it("returns the same ref when a null clear hits a node that is already unlocated", () => {
+    const list = [node({ id: "a", name: "Keep", lat: null, lng: null })];
+    expect(patchNodeSummary(list, update({ nodeId: "a", name: "Keep", lat: null, lng: null }))).toBe(list);
+  });
+
   it("returns the same list ref when the update changes nothing (no needless repaint)", () => {
     const list = [node({ id: "a", name: "Keep", lat: 10, lng: 20 })];
     // re-advert with identical name + omitted coords: every field resolves back to the prev value
@@ -114,4 +127,10 @@ describe("upsertNodePages", () => {
   it("passes undefined caches through", () => {
     expect(upsertNodePages(undefined, update({}))).toBeUndefined();
   });
+
+  it("inserts a fresh node with an explicit null position", () => {
+    const old = pages([node({ id: "a" })]);
+    const out = upsertNodePages(old, update({ nodeId: "new1", lat: null, lng: null }))!;
+    expect(out.pages[0]!.items[1]).toMatchObject({ id: "new1", lat: null, lng: null });
+  });
 });