feat(voice): add reusable geometry actions

- turn named places and mapped landmarks into reusable bounded areas
- count loaded records inside resolved, drawn and annotated geometry
- find recent imagery for an area, the view or the pointer snapshot
- keep osm place search behind an operator-configured overpass endpoint
- preserve cancellation, ownership and follow-up memory across every action
- cover geometry, provider lifecycle, cache isolation and voice routing

server/providers/overpass/osmFeatures.js

@@ -0,0 +1,191 @@
+import { OSM_PRESETS } from '../../../src/data/osmPresets.js';
+
+/**
+ * Bounded, typed OpenStreetMap feature search: one preset from the curated
+ * table inside a bounding box.
+ *
+ * The request carries a preset id, a box, a mode and a limit — never query
+ * text. The server writes the Overpass query itself and bounds it: box size
+ * per mode (a count may cover more ground than a fetch), result count,
+ * Overpass timeout and memory, response bytes, and one query in flight. It
+ * runs only against the operator's `OVERPASS_UPSTREAMS`; the generic
+ * `/api/overpass` guard is untouched.
+ *
+ * There is deliberately no boundary (`area`) filter: Overpass servers differ
+ * in whether they hold area data, and one without it answers zero rather than
+ * failing. The browser filters the box's features by the exact area geometry
+ * instead, so a count inside a province is exact and a box count is labelled
+ * as a box count.
+ */
+export const OSM_FEATURE_LIMITS = Object.freeze({
+  /** Largest box a fetch may cover, in square degrees (~200 × 200 km at the equator). */
+  maxFetchDeg2: 4,
+  /** Largest box a count may cover. */
+  maxCountDeg2: 36,
+  /** Most features one fetch returns. */
+  maxLimit: 1000,
+  /** Overpass server-side timeout, seconds. */
+  timeoutS: 25,
+  /** Overpass server-side memory cap, bytes. */
+  maxsize: 64 * 1024 * 1024,
+  /** Response bytes read from the upstream. */
+  maxResponseBytes: 16 * 1024 * 1024,
+  /** Per-upstream wait: a busy Overpass answers these in 10–30 s. */
+  upstreamTimeoutMs: 40_000,
+});
+
+/** Tags a returned feature keeps, besides the preset's own. */
+const KEPT_TAGS = [
+  'name',
+  'name:en',
+  'operator',
+  'brand',
+  'opening_hours',
+  'wheelchair',
+  'emergency',
+  'healthcare',
+  'addr:street',
+  'addr:city',
+];
+
+const quote = (text) =>
+  `"${String(text).replace(/\\/g, '\\\\').replace(/"/g, '\\"')}"`;
+
+/**
+ * Parse and bound a request. Returns the compiled query or a refusal.
+ * @param {{preset: string, bbox: string|number[], mode?: string, limit?: string|number}} request
+ * @returns {{ok: true, ql: string, mode: string, preset: object, limit: number, boxes: number[][]}|{ok: false, code: string, error: string}}
+ */
+export function compileOsmFeatureQuery(request = {}) {
+  const refuse = (code, error) => ({ ok: false, code, error });
+  const presetId = String(request.preset || '');
+  const preset = Object.hasOwn(OSM_PRESETS, presetId)
+    ? OSM_PRESETS[presetId]
+    : null;
+  if (!preset) return refuse('UNKNOWN_PRESET', 'Unknown feature kind.');
+  const mode = request.mode === 'count' ? 'count' : 'features';
+  const parts = (
+    Array.isArray(request.bbox)
+      ? request.bbox
+      : String(request.bbox || '').split(',')
+  ).map(Number);
+  if (parts.length !== 4 || !parts.every(Number.isFinite))
+    return refuse('BAD_BOX', 'bbox needs west,south,east,north.');
+  const [west, south, east, north] = parts;
+  if (
+    Math.abs(west) > 180 ||
+    Math.abs(east) > 180 ||
+    south < -90 ||
+    north > 90 ||
+    south >= north ||
+    west === east
+  )
+    return refuse('BAD_BOX', 'bbox edges are out of range.');
+  // A box crossing the antimeridian is searched as its two halves.
+  const boxes =
+    west < east
+      ? [[south, west, north, east]]
+      : [
+          [south, west, north, 180],
+          [south, -180, north, east],
+        ];
+  const deg2 = boxes.reduce((sum, [s, w, n, e]) => sum + (n - s) * (e - w), 0);
+  const cap =
+    mode === 'count'
+      ? OSM_FEATURE_LIMITS.maxCountDeg2
+      : OSM_FEATURE_LIMITS.maxFetchDeg2;
+  if (deg2 > cap)
+    return refuse(
+      'AREA_TOO_LARGE',
+      mode === 'count'
+        ? 'That area is too large to search; narrow it down.'
+        : 'That area is too large to list; count first or narrow it down.',
+    );
+  const requested = Number(request.limit);
+  const limit = Math.max(
+    1,
+    Math.min(
+      OSM_FEATURE_LIMITS.maxLimit,
+      Number.isFinite(requested) ? Math.trunc(requested) : 500,
+    ),
+  );
+  const selectors = [];
+  for (const [key, value] of preset.tags)
+    for (const [s, w, n, e] of boxes)
+      selectors.push(
+        `nwr[${quote(key)}=${quote(value)}](${s},${w},${n},${e});`,
+      );
+  const ql =
+    `[out:json][timeout:${OSM_FEATURE_LIMITS.timeoutS}][maxsize:${OSM_FEATURE_LIMITS.maxsize}];` +
+    `(${selectors.join('')});` +
+    (mode === 'count' ? 'out count;' : `out center tags ${limit};`);
+  return { ok: true, ql, mode, preset, limit, boxes };
+}
+
+/**
+ * Overpass JSON → the compact answer the browser gets.
+ * @param {object} payload Parsed Overpass JSON.
+ * @param {{mode: string, preset: object, limit: number}} compiled
+ */
+export function summarizeOsmFeatures(payload, compiled) {
+  if (!Array.isArray(payload?.elements))
+    throw new TypeError('Malformed Overpass feature response');
+  const elements = payload.elements;
+  if (compiled.mode === 'count') {
+    const tags = elements.find((el) => el?.type === 'count')?.tags;
+    const rawTotal = tags?.total;
+    const total = Number(rawTotal);
+    if (
+      !tags ||
+      !Object.hasOwn(tags, 'total') ||
+      !['string', 'number'].includes(typeof rawTotal) ||
+      String(rawTotal).trim() === '' ||
+      !Number.isSafeInteger(total) ||
+      total < 0
+    )
+      throw new TypeError('Malformed Overpass count response');
+    return {
+      mode: 'count',
+      preset: compiled.preset.id,
+      count: total,
+      nodes: Number(tags.nodes) || 0,
+      ways: Number(tags.ways) || 0,
+      relations: Number(tags.relations) || 0,
+    };
+  }
+  const features = [];
+  let unplaced = 0;
+  for (const el of elements) {
+    if (
+      !['node', 'way', 'relation'].includes(el?.type) ||
+      (!Number.isFinite(Number(el?.id)) && typeof el?.id !== 'string')
+    ) {
+      unplaced += 1;
+      continue;
+    }
+    const lat = Number.isFinite(el?.lat) ? el.lat : el?.center?.lat;
+    const lon = Number.isFinite(el?.lon) ? el.lon : el?.center?.lon;
+    if (!Number.isFinite(lat) || !Number.isFinite(lon)) {
+      unplaced += 1;
+      continue;
+    }
+    const tags = {};
+    for (const key of [...KEPT_TAGS, ...compiled.preset.tags.map(([k]) => k)])
+      if (typeof el.tags?.[key] === 'string')
+        tags[key] = el.tags[key].slice(0, 120);
+    features.push({ id: `${el.type}/${el.id}`, lat, lon, tags });
+  }
+  // A genuinely empty `elements` array is authoritative. A non-empty answer
+  // whose every row is unusable is a schema failure, not "zero places"; do
+  // not let the route cache that as current state for a day.
+  if (elements.length && features.length === 0)
+    throw new TypeError('Overpass feature response has no usable rows');
+  return {
+    mode: 'features',
+    preset: compiled.preset.id,
+    count: features.length,
+    features,
+    truncated: elements.length >= compiled.limit,
+    ...(unplaced ? { unplaced } : {}),
+  };
+}

server/providers/overpass/osmFeaturesRoute.js

@@ -0,0 +1,220 @@
+import path from 'node:path';
+import { makeRateLimiter, clientKey } from '../common/rate-limit.js';
+import { createBoundedCache } from '../common/boundedCache.js';
+import {
+  compileOsmFeatureQuery,
+  OSM_FEATURE_LIMITS,
+  summarizeOsmFeatures,
+} from './osmFeatures.js';
+import { resolveOverpassUpstreams } from './constants.js';
+import { fetchOverpassPayload, overpassPayloadIsData } from './transport.js';
+
+/** Places of interest change slowly: answers are kept a day. */
+const OSM_FEATURES_TTL_MS = 86_400_000;
+/** Cache-key version; nothing cached under another version is reused. */
+const CACHE_VERSION = 'v2';
+
+/** Never simplify: these answers are points and counts, not drawings. */
+const keepBody = (body) => body;
+
+const jsonError = (status, error, extra = {}) => ({
+  status,
+  body: JSON.stringify({ error, ...extra }),
+});
+
+/**
+ * One upstream Overpass query at a time, with identical requests sharing it
+ * and answers in a bounded memory + disk cache.
+ */
+function createOverpassAnswerer({
+  fetchPayload,
+  cache,
+  maxResponseBytes,
+  upstreamTimeoutMs,
+}) {
+  const inFlight = new Map();
+  let running = 0;
+  return async function answer(key, ql, summarize, signal = null) {
+    signal?.throwIfAborted?.();
+    const held = await cache.get(key);
+    signal?.throwIfAborted?.();
+    if (typeof held === 'string')
+      return { status: 200, body: held, cache: 'HIT' };
+    let operation = inFlight.get(key);
+    if (operation?.controller.signal.aborted) {
+      inFlight.delete(key);
+      operation = null;
+    }
+    if (!operation) {
+      if (running >= 1)
+        return {
+          ...jsonError(
+            503,
+            'Another map search is running — try again shortly.',
+          ),
+          retryAfter: '3',
+        };
+      running += 1;
+      const controller = new AbortController();
+      operation = { controller, waiters: 0, settled: false, promise: null };
+      const owned = operation;
+      owned.promise = (async () => {
+        try {
+          const payload = await fetchPayload(
+            `data=${encodeURIComponent(ql)}`,
+            maxResponseBytes,
+            {
+              simplify: keepBody,
+              timeoutMs: upstreamTimeoutMs,
+              signal: controller.signal,
+            },
+          );
+          if (!overpassPayloadIsData(payload))
+            return {
+              ...jsonError(
+                payload?.rateLimited ? 429 : 503,
+                'OpenStreetMap search is unavailable right now.',
+              ),
+              retryAfter: '10',
+            };
+          let parsed;
+          try {
+            parsed = JSON.parse(payload.body);
+          } catch {
+            return jsonError(
+              502,
+              'OpenStreetMap returned an unreadable answer.',
+            );
+          }
+          const body = JSON.stringify(summarize(parsed));
+          controller.signal.throwIfAborted();
+          await cache.set(key, body);
+          controller.signal.throwIfAborted();
+          return { status: 200, body, cache: 'MISS' };
+        } catch {
+          return jsonError(502, 'OpenStreetMap search failed.');
+        } finally {
+          owned.settled = true;
+          running -= 1;
+          if (inFlight.get(key) === owned) inFlight.delete(key);
+        }
+      })();
+      inFlight.set(key, owned);
+    }
+
+    operation.waiters += 1;
+    let abort = null;
+    const abandoned = signal
+      ? new Promise((_, reject) => {
+          abort = () => {
+            operation.waiters -= 1;
+            if (operation.waiters === 0 && !operation.settled)
+              operation.controller.abort();
+            reject(signal.reason ?? new DOMException('Aborted', 'AbortError'));
+          };
+          signal.addEventListener('abort', abort, { once: true });
+          if (signal.aborted) abort();
+        })
+      : null;
+    try {
+      return await (abandoned
+        ? Promise.race([operation.promise, abandoned])
+        : operation.promise);
+    } finally {
+      if (signal && abort) signal.removeEventListener('abort', abort);
+      if (!signal?.aborted) operation.waiters -= 1;
+    }
+  };
+}
+
+function sender(res) {
+  return ({ status, body, cache, retryAfter }) => {
+    if (res.writableEnded) return;
+    res.writeHead(status, {
+      'Content-Type': 'application/json',
+      'Cache-Control': 'no-store',
+      ...(cache ? { 'X-OSM-Cache': cache } : {}),
+      ...(retryAfter ? { 'Retry-After': retryAfter } : {}),
+    });
+    res.end(body);
+  };
+}
+
+/**
+ * Install `GET /api/osm/features?preset=&bbox=w,s,e,n[&mode=count][&limit=]`:
+ * one curated preset inside a box, answered by the operator's Overpass
+ * (`OVERPASS_UPSTREAMS`). With none configured the route answers
+ * `OVERPASS_NOT_CONFIGURED` and fetches nothing; public Nominatim is never a
+ * substitute for bulk place search.
+ *
+ * @param {{use: Function}} middlewares
+ * @param {{fetchPayload?: Function, featuresCache?: object, cacheRoot?: string|null, configured?: () => boolean}} [deps]
+ */
+export function installOsmFeaturesRoute(
+  middlewares,
+  {
+    fetchPayload = fetchOverpassPayload,
+    configured = () => resolveOverpassUpstreams().length > 0,
+    cacheRoot = path.join(process.cwd(), '.gev-cache'),
+    featuresCache = createBoundedCache({
+      dir: cacheRoot ? path.join(cacheRoot, 'osm-features') : null,
+      ttlMs: OSM_FEATURES_TTL_MS,
+      maxMemoryEntries: 60,
+      maxDiskEntries: 400,
+      maxDiskBytes: 256 * 1024 * 1024,
+    }),
+  } = {},
+) {
+  const limiter = makeRateLimiter({ windowMs: 60_000, max: 12, globalMax: 30 });
+  const features = createOverpassAnswerer({
+    fetchPayload,
+    cache: featuresCache,
+    maxResponseBytes: OSM_FEATURE_LIMITS.maxResponseBytes,
+    upstreamTimeoutMs: OSM_FEATURE_LIMITS.upstreamTimeoutMs,
+  });
+
+  middlewares.use('/api/osm/features', async (req, res) => {
+    const send = sender(res);
+    if (req.method !== 'GET') return send(jsonError(405, 'Method Not Allowed'));
+    if (!configured())
+      return send(
+        jsonError(503, 'Place search needs a configured Overpass server.', {
+          code: 'OVERPASS_NOT_CONFIGURED',
+          retryable: false,
+        }),
+      );
+    const url = new URL(req.url || '', 'http://localhost');
+    const compiled = compileOsmFeatureQuery({
+      preset: url.searchParams.get('preset'),
+      bbox: url.searchParams.get('bbox'),
+      mode: url.searchParams.get('mode'),
+      limit: url.searchParams.get('limit'),
+    });
+    if (!compiled.ok)
+      return send(jsonError(400, compiled.error, { code: compiled.code }));
+    if (!limiter(clientKey(req)))
+      return send({
+        ...jsonError(429, 'Rate limit exceeded'),
+        retryAfter: '10',
+      });
+    const controller = new AbortController();
+    const abort = () => controller.abort();
+    req.once?.('aborted', abort);
+    res.once?.('close', abort);
+    try {
+      const answer = await features(
+        `${CACHE_VERSION}|features|${compiled.ql}`,
+        compiled.ql,
+        (parsed) => summarizeOsmFeatures(parsed, compiled),
+        controller.signal,
+      );
+      if (!controller.signal.aborted) send(answer);
+    } catch {
+      if (!controller.signal.aborted)
+        send(jsonError(502, 'OpenStreetMap search failed.'));
+    } finally {
+      req.removeListener?.('aborted', abort);
+      res.removeListener?.('close', abort);
+    }
+  });
+}

server/providers/overpass/transport.js

@@ -115,6 +115,8 @@ async function fetchOverpassPayload(
     readBody = readResponseTextCapped,
     simplify = simplifyOverpassPayloadBody,
     now = Date.now,
+    timeoutMs = OVERPASS_TIMEOUT_MS,
+    signal = null,
   } = {},
 ) {
   if (!endpoints.length) return overpassNotConfigured();
@@ -126,7 +128,10 @@ async function fetchOverpassPayload(
       continue;
     }
     const controller = new AbortController();
-    const timeoutId = setTimeout(() => controller.abort(), OVERPASS_TIMEOUT_MS);
+    const timeoutId = setTimeout(() => controller.abort(), timeoutMs);
+    const requestSignal = signal
+      ? AbortSignal.any([signal, controller.signal])
+      : controller.signal;
     try {
       const requestUrl = new URL(endpoint);
       const authorization =
@@ -147,7 +152,7 @@ async function fetchOverpassPayload(
           ...(authorization ? { Authorization: authorization } : {}),
         },
         body,
-        signal: controller.signal,
+        signal: requestSignal,
       });
       const responseBody = await readBody(upstream, maxResponseBytes);
       const rateLimited =
@@ -189,7 +194,12 @@ async function fetchOverpassPayload(
         endpoint: 'configured',
         rateLimited: false,
       };
-    } catch {
+    } catch (error) {
+      // A route whose last requester disconnected owns this cancellation. It
+      // is not evidence that the configured upstream is unhealthy, so do not
+      // put the endpoint on cooldown or translate the abort into a response
+      // that a now-gone client could cache.
+      if (signal?.aborted) throw signal.reason ?? error;
       const failures = (previous?.failures || 0) + 1;
       const delay = retryDelay(null, failures - 1, now());
       cooldowns.set(endpoint, { until: now() + delay, failures, status: 502 });