refactor: separate map feature queries and source records

src/layers/installations/ingestion.js

@@ -1,5 +1,3 @@
-import { normalizeMilitaryInstallations } from '../../data/militaryInstallationData.js';
-
 export function createIngestion({
   state: layerState,
   services,
@@ -58,19 +56,15 @@ export function createIngestion({
       // A SATURATED snapped tile was truncated upstream, so features from the
       // snap's extra ring may have crowded out sites actually on screen. Re-ask
       // for the exact viewport (separately keyed and cached) before rendering.
-      let saturated = parts.model.installationResponseSaturated(payload);
+      let saturated = payload.saturated === true;
       if (saturated) {
         payload = await fetchInstallations(true);
-        saturated = parts.model.installationResponseSaturated(payload);
+        saturated = payload.saturated === true;
       }
-      const normalized = normalizeMilitaryInstallations(
-        payload,
-        payload.retrievedAt || new Date().toISOString(),
-      );
       // The proxy answers a bbox at least as large as the viewport; keep only what
       // was actually asked for so nothing off-screen reaches the map or the
       // "current viewport only" context claim.
-      const records = normalized.records.filter((record) =>
+      const records = payload.records.filter((record) =>
         parts.model.installationWithinViewport(record, box),
       );
       let placesError = null;

src/layers/installations/model.js

@@ -1,3 +1,4 @@
+import { installationResponseSaturated } from './source.js';
 import * as Cesium from 'cesium';
 import {
   EARTH_MEAN_RADIUS_M,
@@ -137,23 +138,6 @@ export function createModel({ state: layerState, services, parts, source }) {
     return record.osmType !== 'node';
   }
 
-  /**
-   * Whether a response was truncated at the upstream element cap.
-   *
-   * The proxy states this outright, but a `saturated`-less payload is NOT
-   * evidence of a complete answer: entries cached before the saturation guard
-   * shipped predate the field and live for 30 days. Fall back to deriving it from
-   * the element count against the cap the payload itself reports.
-   * @param {{saturated?: boolean, elements?: Array, elementCap?: number}} payload
-   * @returns {boolean}
-   */
-
-  function installationResponseSaturated(payload) {
-    if (typeof payload?.saturated === 'boolean') return payload.saturated;
-    const cap = Number(payload?.elementCap);
-    if (!Number.isFinite(cap) || cap <= 0) return false;
-    return Array.isArray(payload?.elements) && payload.elements.length >= cap;
-  }
   return {
     approximateSurfaceDistanceM,
     colorFor,

src/layers/installations/source.js

@@ -1,3 +1,13 @@
+import { normalizeMilitaryInstallations } from '../../data/militaryInstallationData.js';
+
+/** Preserve legacy cache admission even when the explicit saturation flag is absent. */
+export function installationResponseSaturated(payload) {
+  if (typeof payload?.saturated === 'boolean') return payload.saturated;
+  const cap = Number(payload?.elementCap);
+  if (!Number.isFinite(cap) || cap <= 0) return false;
+  return Array.isArray(payload?.elements) && payload.elements.length >= cap;
+}
+
 /** Read mapped installations and explicit nearby-place searches through fixed endpoints. */
 export function createInstallationSource({
   fetchImpl = (...args) => globalThis.fetch(...args),
@@ -43,7 +53,14 @@ export function createInstallationSource({
         );
       if (!Array.isArray(body?.elements))
         throw new Error('Malformed installation snapshot');
-      return body;
+      return {
+        ...normalizeMilitaryInstallations(
+          body,
+          body.retrievedAt || new Date().toISOString(),
+        ),
+        status: body.status,
+        saturated: installationResponseSaturated(body),
+      };
     },
     async searchNearby({ latitude, longitude, radiusM }, { signal } = {}) {
       if (

src/layers/installations/source.test.mjs

@@ -57,3 +57,30 @@ test('installation response parsing respects cancellation before any follow-on s
     { name: 'AbortError' },
   );
 });
+
+test('mapped-site sources normalize records and derive saturation from legacy cache metadata', async () => {
+  const source = createInstallationSource({
+    fetchImpl: async () =>
+      Response.json({
+        elements: [
+          {
+            type: 'node',
+            id: 1,
+            lat: 30.2,
+            lon: -97.7,
+            tags: { military: 'airfield', name: 'Fixture Field' },
+          },
+        ],
+        elementCap: 1,
+        status: 'stale',
+        retrievedAt: '2026-01-01T00:00:00Z',
+      }),
+  });
+  const payload = await source.getMappedSites(box);
+  assert.equal(payload.records[0].name, 'Fixture Field');
+  assert.equal(payload.records[0].latitude, 30.2);
+  assert.equal(payload.records[0].retrievedAt, '2026-01-01T00:00:00Z');
+  assert.equal(payload.saturated, true);
+  assert.equal(payload.status, 'stale');
+  assert.equal('elements' in payload, false);
+});