style(wind): adopt automatically discovered runtime formatting

server/providers/wind/catalog.js

@@ -7,9 +7,14 @@ export function gfsObjectKey({ date, hour, forecastHour = 0 }) {
 }
 
 /** Select the latest GFS cycle that should be available. */
-export function selectLatestGfsCycle(nowMs, { availabilityLagMs = 5 * 3600_000 } = {}) {
+export function selectLatestGfsCycle(
+  nowMs,
+  { availabilityLagMs = 5 * 3600_000 } = {},
+) {
   const d = new Date(nowMs - availabilityLagMs);
-  const date = new Date(Date.UTC(d.getUTCFullYear(), d.getUTCMonth(), d.getUTCDate()));
+  const date = new Date(
+    Date.UTC(d.getUTCFullYear(), d.getUTCMonth(), d.getUTCDate()),
+  );
   const hour = Math.floor(d.getUTCHours() / 6) * 6;
   date.setUTCHours(hour);
   return { date: date.toISOString().slice(0, 10).replaceAll('-', ''), hour };

server/providers/wind/decode.js

@@ -1,17 +1,20 @@
 /** Lazy shared ecCodes WASM instance, created only for an active wind request. */
 let eccodesPromise = null;
 function loadEccodes() {
-  eccodesPromise ??= import('@meri-imperiumi/eccodes-wasm').then(module => module.createEccodes()).catch(error => {
-    eccodesPromise = null;
-    throw error;
-  });
+  eccodesPromise ??= import('@meri-imperiumi/eccodes-wasm')
+    .then((module) => module.createEccodes())
+    .catch((error) => {
+      eccodesPromise = null;
+      throw error;
+    });
   return eccodesPromise;
 }
 
 /** Decode one bounded message in WASM memory without mounting the host filesystem. */
 export async function decodeWindGribMessage(buffer, { eccodesModule } = {}) {
-  if (buffer.byteLength > 8 * 1024 * 1024) throw new Error('Wind GRIB exceeds byte budget');
-  const eccodes = eccodesModule ?? await loadEccodes();
+  if (buffer.byteLength > 8 * 1024 * 1024)
+    throw new Error('Wind GRIB exceeds byte budget');
+  const eccodes = eccodesModule ?? (await loadEccodes());
   // Everything after this await is synchronous. A shared virtual file is safe
   // across U/V and model requests and its storage is released after each decode.
   const file = '/gev-wind.grib2';
@@ -21,9 +24,17 @@ export async function decodeWindGribMessage(buffer, { eccodesModule } = {}) {
     handle = eccodes.openGrib(file);
     const ni = handle.getLong('Ni');
     const nj = handle.getLong('Nj');
-    if (!Number.isInteger(ni) || !Number.isInteger(nj) || ni < 1 || nj < 1 || ni * nj > 2_000_000) throw new Error('Invalid wind GRIB geometry');
+    if (
+      !Number.isInteger(ni) ||
+      !Number.isInteger(nj) ||
+      ni < 1 ||
+      nj < 1 ||
+      ni * nj > 2_000_000
+    )
+      throw new Error('Invalid wind GRIB geometry');
     return {
-      ni, nj,
+      ni,
+      nj,
       lo1: handle.getDouble('longitudeOfFirstGridPointInDegrees'),
       la1: handle.getDouble('latitudeOfFirstGridPointInDegrees'),
       di: handle.getDouble('iDirectionIncrementInDegrees'),

server/providers/wind/gfs.js

@@ -41,7 +41,10 @@ export function parseGfsIdx(text) {
  * @param {{level?: string}} [options]
  * @returns {{u: {start: number, end: number}, v: {start: number, end: number}}}
  */
-export function windMessageRanges(parsed, { level = '10 m above ground' } = {}) {
+export function windMessageRanges(
+  parsed,
+  { level = '10 m above ground' } = {},
+) {
   const range = (variable) => {
     const index = parsed.messages.findIndex(
       (message) => message.variable === variable && message.level === level,
@@ -57,7 +60,10 @@ export function windMessageRanges(parsed, { level = '10 m above ground' } = {})
 /** Fetch a bounded text response as a Buffer. */
 export async function fetchText({ url, fetchImpl = fetch, signal }) {
   const response = await fetchImpl(url, { signal, redirect: 'error' });
-  if (!response.ok) { await response.body?.cancel(); throw new Error('Wind upstream unavailable'); }
+  if (!response.ok) {
+    await response.body?.cancel();
+    throw new Error('Wind upstream unavailable');
+  }
   return Buffer.from(await readWindBody(response, 2 * 1024 * 1024, signal));
 }
 
@@ -73,7 +79,13 @@ export async function fetchRange({
   signal,
   maxBytes = 8 * 1024 * 1024,
 }) {
-  if (!Number.isSafeInteger(start) || !Number.isSafeInteger(end) || start < 0 || end < start || end - start + 1 > maxBytes)
+  if (
+    !Number.isSafeInteger(start) ||
+    !Number.isSafeInteger(end) ||
+    start < 0 ||
+    end < start ||
+    end - start + 1 > maxBytes
+  )
     throw new Error('range too large');
   const response = await fetchImpl(url, {
     signal,
@@ -82,19 +94,35 @@ export async function fetchRange({
   });
   const validStatus =
     response.status === 206 || (response.status === 200 && start === 0);
-  if (!validStatus || !response.ok) { await response.body?.cancel(); throw new Error('Wind upstream unavailable'); }
-  const buffer = Buffer.from(await readWindBody(response, end - start + 1, signal));
+  if (!validStatus || !response.ok) {
+    await response.body?.cancel();
+    throw new Error('Wind upstream unavailable');
+  }
+  const buffer = Buffer.from(
+    await readWindBody(response, end - start + 1, signal),
+  );
   if (buffer.length !== end - start + 1)
     throw new Error('invalid range length');
   return buffer;
 }
 
-import { GFS_BUCKET, gfsObjectKey, selectLatestGfsCycle, nearestGfsStep } from './catalog.js';
+import {
+  GFS_BUCKET,
+  gfsObjectKey,
+  selectLatestGfsCycle,
+  nearestGfsStep,
+} from './catalog.js';
 import { decodeWindGribMessage } from './decode.js';
 import { resampleWindGrid } from './grid.js';
 
 /** Fetch and decode the GFS 10 m wind field valid closest to now. */
-export async function fetchGfsWind({ fetchImpl = fetch, now = () => Date.now(), targetDx = 1, decodeImpl = decodeWindGribMessage, signal } = {}) {
+export async function fetchGfsWind({
+  fetchImpl = fetch,
+  now = () => Date.now(),
+  targetDx = 1,
+  decodeImpl = decodeWindGribMessage,
+  signal,
+} = {}) {
   const nowMs = now();
   const cycle = selectLatestGfsCycle(nowMs);
   const runMs = Date.UTC(
@@ -114,8 +142,24 @@ export async function fetchGfsWind({ fetchImpl = fetch, now = () => Date.now(),
     fetchRange({ url: base, ...ranges.v, fetchImpl, signal }),
   ]);
   const [u, v] = await Promise.all([decodeImpl(uBuffer), decodeImpl(vBuffer)]);
-  const grid = resampleWindGrid({ u: u.values, v: v.values, ni: u.ni, nj: u.nj, lo1: u.lo1, la1: u.la1, di: u.di, dj: u.dj, dx: targetDx, dy: targetDx });
+  const grid = resampleWindGrid({
+    u: u.values,
+    v: v.values,
+    ni: u.ni,
+    nj: u.nj,
+    lo1: u.lo1,
+    la1: u.la1,
+    di: u.di,
+    dj: u.dj,
+    dx: targetDx,
+    dy: targetDx,
+  });
   const runIso = new Date(runMs).toISOString();
   const validIso = new Date(runMs + forecastHour * 3600_000).toISOString();
-  return { cycle: { ...cycle, forecastHour, runIso, validIso }, level: '10 m above ground', units: 'm/s', grid };
+  return {
+    cycle: { ...cycle, forecastHour, runIso, validIso },
+    level: '10 m above ground',
+    units: 'm/s',
+    grid,
+  };
 }

server/providers/wind/grid.js

@@ -21,7 +21,22 @@ export function resampleWindGrid({
   dx = 1,
   dy = 1,
 }) {
-  if (!Number.isInteger(ni) || !Number.isInteger(nj) || ni < 1 || nj < 1 || ni * nj > 2_000_000 || u?.length !== ni * nj || v?.length !== ni * nj || ![lo1, la1, di, dj, dx, dy].every(Number.isFinite) || di <= 0 || dj <= 0 || dx < 0.25 || dy < 0.25 || dx > 180 || dy > 180)
+  if (
+    !Number.isInteger(ni) ||
+    !Number.isInteger(nj) ||
+    ni < 1 ||
+    nj < 1 ||
+    ni * nj > 2_000_000 ||
+    u?.length !== ni * nj ||
+    v?.length !== ni * nj ||
+    ![lo1, la1, di, dj, dx, dy].every(Number.isFinite) ||
+    di <= 0 ||
+    dj <= 0 ||
+    dx < 0.25 ||
+    dy < 0.25 ||
+    dx > 180 ||
+    dy > 180
+  )
     throw new Error('Invalid wind grid geometry');
   const nx = Math.round(360 / dx);
   const ny = Math.round(180 / dy) + 1;

server/providers/wind/ifs.js

@@ -89,7 +89,8 @@ export function ifsWindRanges(entries) {
 export function nearestIfsStep(hours, cycleHour) {
   const max = cycleHour === 6 || cycleHour === 18 ? 144 : 360;
   const value = Math.max(0, Number.isFinite(hours) ? hours : 0);
-  const step = value <= 144 ? Math.round(value / 3) * 3 : Math.round(value / 6) * 6;
+  const step =
+    value <= 144 ? Math.round(value / 3) * 3 : Math.round(value / 6) * 6;
   return Math.max(0, Math.min(max, step));
 }