mirror of
https://github.com/bilawalsidhu/gods-eye-view.git
synced 2026-11-05 19:04:02 +00:00
728 lines
25 KiB
JavaScript
728 lines
25 KiB
JavaScript
import { createRainViewerGovernor } from './rainViewerGovernor.js';
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import { readResponseTextCapped } from './common/http.js';
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import { readWindBody as readBytesCapped } from '../../src/sources/windBody.js';
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const BASE = 'https://nowcoast.noaa.gov/geoserver/observations/';
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const RAINVIEWER_MANIFEST =
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'https://api.rainviewer.com/public/weather-maps.json';
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const RAINVIEWER_TILES = 'https://tilecache.rainviewer.com';
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const HOUR = 3600_000;
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const PRODUCTS = Object.freeze({
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lightning: Object.freeze({
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service: 'lightning_detection',
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layer: 'ldn_lightning_strike_density',
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style: 'lightning_density',
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title: 'Lightning density · 15 min',
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coverage:
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'Pacific and Americas: 110°E across the dateline to 0°, 25°S–80°N; not global coverage.',
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description:
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'Observed 15-minute lightning strike density on an approximately 8 km grid, scaled as strikes/km²/min ×10³. Ground-network density, not individual GLM flashes.',
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attribution: 'NOAA/NWS nowCOAST; derived from Vaisala NLDN/GLD360',
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metadataTtlMs: 600_000,
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image: Object.freeze({ width: 4096, height: 2048 }),
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}),
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radar: Object.freeze({
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service: 'weather_radar',
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layer: 'conus_base_reflectivity_mosaic',
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style: 'weather_radar_base_reflectivity',
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title: 'CONUS radar reflectivity',
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coverage:
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'Contiguous United States; gaps do not establish absence of precipitation.',
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description:
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'Observed MRMS radar base reflectivity (dBZ), approximately 1 km and 4-minute updates; not a rainfall forecast.',
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image: Object.freeze({ width: 4096, height: 2048 }),
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}),
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'radar-global': Object.freeze({
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service: 'rainviewer',
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title: 'Global radar reflectivity',
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coverage: 'Global · where radars exist',
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description:
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'RainViewer global radar composite (dBZ). Coverage follows national radar networks; a gap does not mean no rain.',
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source: 'RainViewer',
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attribution: 'RainViewer',
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metadataTtlMs: 300_000,
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tilingScheme: 'web-mercator',
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maxLevel: 7,
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bounds: Object.freeze({
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west: -180,
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south: -85.0511,
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east: 180,
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north: 85.0511,
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}),
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image: Object.freeze({ width: 2048, height: 1024 }),
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}),
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clouds: Object.freeze({
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service: 'satellite',
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layer: 'global_longwave_imagery_mosaic',
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style: 'reflectance',
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title: 'Global satellite infrared',
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coverage:
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'Global mosaic with incomplete polar coverage; nominal coverage 60°S–60°N.',
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description:
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'Longwave infrared cloud and land/sea temperature patterns, approximately 3 km; hourly updates with 2–3 hour source latency. Not a cloud-only mask.',
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image: Object.freeze({ width: 2048, height: 1024 }),
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}),
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'clouds-regional': Object.freeze({
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service: 'satellite',
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layer: 'goes_longwave_imagery',
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style: 'goes-lir',
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title: 'GOES regional satellite infrared',
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coverage:
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'GOES East/West regional North American coverage; not a global image.',
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description:
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'GOES-19/18 longwave infrared Band 14 cloud and surface temperature patterns, approximately 2 km and 5-minute updates. Not a cloud-only mask.',
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image: Object.freeze({ width: 4096, height: 2048 }),
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}),
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});
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// Whole-extent images: 2:1 sizes up to each product's largest (the default).
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const IMAGE_SIZES = Object.freeze(['1024x512', '2048x1024', '4096x2048']);
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// Detail windows: any product up to 4096×2048 (the default).
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const DETAIL_IMAGE = Object.freeze({ width: 4096, height: 2048 });
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const BBOX_STEP = 0.25;
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const MAX_IMAGE_BYTES = 16 * 1024 * 1024;
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function failure(code, status = 503) {
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return Object.assign(new Error(code), { code, status });
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}
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/** Canonicalize only explicit UTC observations; never expand time intervals. */
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function observationTime(value) {
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if (
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typeof value !== 'string' ||
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!/^\d{4}-\d{2}-\d{2}T\d{2}:\d{2}:\d{2}(?:\.\d{3})?Z$/.test(value)
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)
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return null;
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const date = new Date(value);
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if (!Number.isFinite(date.getTime())) return null;
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const canonical = date.toISOString();
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return canonical.replace('.000Z', 'Z') === value.replace('.000Z', 'Z')
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? canonical
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: null;
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}
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/** Read the named leaf from bounded capabilities without resolving XML entities. */
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export function parseWeatherCapabilities(xml, product, nowMs = Date.now()) {
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const spec = PRODUCTS[product];
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if (
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!spec ||
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typeof xml !== 'string' ||
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xml.length > 512 * 1024 ||
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/<!DOCTYPE|<!ENTITY/i.test(xml)
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)
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throw failure('invalid_weather_metadata');
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const stack = [];
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let leaf = null;
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let tags = 0;
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for (const match of xml.matchAll(/<\/?(?:[\w.-]+:)?Layer\b[^>]*>/g)) {
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if (++tags > 2048) throw failure('invalid_weather_metadata');
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if (!match[0].startsWith('</')) {
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if (stack.length) stack.at(-1).nested = true;
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if (stack.length >= 16 || match[0].endsWith('/>'))
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throw failure('invalid_weather_metadata');
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stack.push({ start: match.index + match[0].length, nested: false });
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} else {
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const opened = stack.pop();
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if (!opened) throw failure('invalid_weather_metadata');
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if (opened.nested) continue;
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const candidate = xml.slice(opened.start, match.index);
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const name = candidate
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.match(/<(?:[\w.-]+:)?Name\s*>([^<]+)<\/(?:[\w.-]+:)?Name>/)?.[1]
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?.trim();
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if (name === spec.layer) {
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if (leaf !== null) throw failure('invalid_weather_metadata');
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leaf = candidate;
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}
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}
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}
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if (stack.length || !leaf) throw failure('invalid_weather_metadata');
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const box = leaf.match(
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/<(?:[\w.-]+:)?EX_GeographicBoundingBox\s*>([\s\S]*?)<\/(?:[\w.-]+:)?EX_GeographicBoundingBox>/,
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)?.[1];
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const bounds = {};
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for (const [key, tag] of Object.entries({
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west: 'westBoundLongitude',
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south: 'southBoundLatitude',
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east: 'eastBoundLongitude',
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north: 'northBoundLatitude',
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})) {
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const value = box
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?.match(
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new RegExp(`<(?:[\\w.-]+:)?${tag}\\s*>([^<]+)</(?:[\\w.-]+:)?${tag}>`),
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)?.[1]
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?.trim();
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bounds[key] = value ? Number(value) : NaN;
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}
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if (
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!Object.values(bounds).every(Number.isFinite) ||
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bounds.west < -180 ||
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bounds.east > 180 ||
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bounds.south < -90 ||
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bounds.north > 90 ||
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bounds.west >= bounds.east ||
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bounds.south >= bounds.north
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)
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throw failure('invalid_weather_metadata');
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const dimensions = [
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...leaf.matchAll(
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/<(?:[\w.-]+:)?Dimension\b([^>]*)>([^<]*)<\/(?:[\w.-]+:)?Dimension>/g,
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),
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].filter((entry) => /\bname\s*=\s*["']time["']/.test(entry[1]));
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if (
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dimensions.length !== 1 ||
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!/\bunits\s*=\s*["']ISO8601["']/.test(dimensions[0][1])
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)
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throw failure('invalid_weather_metadata');
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const raw = dimensions[0][2].trim().split(',');
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if (!raw.length || raw.length > 512)
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throw failure('invalid_weather_metadata');
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const times = raw.map((value) => observationTime(value.trim()));
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if (times.some((value) => !value || Date.parse(value) > nowMs + 5 * 60_000))
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throw failure('invalid_weather_metadata');
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const defaultTime = observationTime(
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dimensions[0][1].match(/\bdefault\s*=\s*["']([^"']+)["']/)?.[1],
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);
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if (!defaultTime || !times.includes(defaultTime))
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throw failure('invalid_weather_metadata');
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const recent = [...new Set(times)]
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.filter((value) => nowMs - Date.parse(value) <= 24 * HOUR)
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.sort()
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.slice(-26);
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if (!recent.length) throw failure('weather_observations_expired');
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return { bounds, times: recent.slice(-13), allowedTimes: recent };
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}
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/** Accept only observed frames with bounded paths; never trust the manifest host. */
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export function parseRainViewerManifest(text) {
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const manifest = JSON.parse(text);
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if (manifest?.version !== '2.0' || !Array.isArray(manifest.radar?.past))
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throw failure('invalid_weather_metadata');
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const frames = new Map();
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for (const frame of manifest.radar.past) {
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if (
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!Number.isSafeInteger(frame?.time) ||
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frame.time <= 0 ||
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typeof frame.path !== 'string' ||
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!/^\/v2\/radar\/[A-Za-z0-9]{1,64}$/.test(frame.path)
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)
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continue;
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const date = new Date(frame.time * 1000);
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if (!Number.isFinite(date.getTime()) || date.getUTCFullYear() > 9999)
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continue;
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frames.set(date.toISOString(), frame.path);
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}
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const times = [...frames.keys()].sort().slice(-13);
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if (!times.length) throw failure('invalid_weather_metadata');
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return {
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bounds: PRODUCTS['radar-global'].bounds,
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times,
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allowedTimes: times,
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framePaths: Object.fromEntries(
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times.map((time) => [time, frames.get(time)]),
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),
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};
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}
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/** Web Mercator XYZ has one square root, unlike NOAA's geographic grid. */
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export function rainViewerTileCoordinates(z, x, y) {
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if (
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![z, x, y].every(Number.isInteger) ||
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z < 0 ||
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z > 7 ||
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x < 0 ||
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y < 0 ||
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x >= 2 ** z ||
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y >= 2 ** z
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)
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throw failure('invalid_weather_tile', 400);
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return [z, x, y];
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}
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/** A detail window `west,south,east,north` in degrees, rounded to 0.25° so cache
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* keys repeat, with a 2:1 aspect within 1 %; null when absent. Containment in
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* the product bounds is checked once the metadata is known. */
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export function weatherImageBbox(value) {
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if (value === null) return null;
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const parts = value.split(',');
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if (
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parts.length !== 4 ||
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parts.some((part) => !/^-?\d{1,3}(?:\.\d{1,6})?$/.test(part))
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)
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throw failure('invalid_weather_bbox', 400);
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// `+ 0` turns a rounded -0 into 0 so equal windows share one key.
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const [west, south, east, north] = parts.map(
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(part) => Math.round(Number(part) / BBOX_STEP) * BBOX_STEP + 0,
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);
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if (
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west < -180 ||
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east > 180 ||
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south < -90 ||
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north > 90 ||
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west >= east ||
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south >= north ||
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Math.abs((east - west) / (north - south) / 2 - 1) > 0.01
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)
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throw failure('invalid_weather_bbox', 400);
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return [west, south, east, north];
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}
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/** GeographicTilingScheme's two longitude tiles and one latitude tile at level zero. */
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export function weatherTileBounds(z, x, y) {
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if (
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![z, x, y].every(Number.isInteger) ||
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z < 0 ||
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z > 6 ||
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x < 0 ||
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y < 0 ||
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x >= 2 ** (z + 1) ||
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y >= 2 ** z
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)
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throw failure('invalid_weather_tile', 400);
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const span = 180 / 2 ** z;
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return [
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-180 + x * span,
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90 - (y + 1) * span,
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-180 + (x + 1) * span,
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90 - y * span,
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];
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}
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function validatePng(bytes, width, height) {
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const buffer = Buffer.from(bytes.buffer, bytes.byteOffset, bytes.byteLength);
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if (
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buffer.length < 33 ||
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!buffer
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.subarray(0, 8)
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.equals(Buffer.from([137, 80, 78, 71, 13, 10, 26, 10])) ||
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buffer.readUInt32BE(8) !== 13 ||
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buffer.toString('ascii', 12, 16) !== 'IHDR' ||
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buffer.readUInt32BE(16) !== width ||
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buffer.readUInt32BE(20) !== height
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)
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throw failure('invalid_weather_image');
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return buffer;
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}
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/** Fixed observed-weather metadata and tiles; no client-supplied destinations. */
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export function weatherProxy({
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fetchImpl = fetch,
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now = () => Date.now(),
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timeoutMs = 12_000,
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rainViewerSleep,
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} = {}) {
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const admitRainViewerTile = createRainViewerGovernor();
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const metadata = new Map();
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const attempts = new Map();
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const operations = new Map();
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const pending = [];
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const tiles = new Map();
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const tileFailures = new Map();
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let tileBytes = 0;
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let active = 0;
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function pump() {
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while (active < 8 && pending.length) {
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const operation = pending.shift();
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if (operation.controller.signal.aborted) continue;
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active++;
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operation.started = true;
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Promise.resolve()
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.then(() => operation.work(operation.controller.signal))
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.then(operation.resolve, operation.reject)
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.finally(() => {
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active--;
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pump();
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});
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}
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}
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async function shared(key, work, clientSignal, extraWaitMs = 0) {
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clientSignal.throwIfAborted();
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let operation = operations.get(key);
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if (operation?.controller.signal.aborted) {
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operations.delete(key);
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operation = null;
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}
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if (!operation) {
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if (operations.size >= 120 || pending.length >= 96)
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throw failure('weather_busy', 429);
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const controller = new AbortController();
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operation = { controller, work, waiters: 0, started: false };
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operation.promise = new Promise((resolve, reject) => {
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operation.resolve = resolve;
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operation.reject = reject;
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});
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const cancel = () => {
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const index = pending.indexOf(operation);
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if (index >= 0) pending.splice(index, 1);
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operation.reject(failure('weather_request_cancelled'));
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};
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controller.signal.addEventListener('abort', cancel, { once: true });
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const timer = setTimeout(
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() => controller.abort(),
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timeoutMs + extraWaitMs,
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);
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operation.promise = operation.promise.finally(() => {
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clearTimeout(timer);
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controller.signal.removeEventListener('abort', cancel);
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if (operations.get(key) === operation) operations.delete(key);
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});
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operations.set(key, operation);
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pending.push(operation);
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pump();
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}
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operation.waiters++;
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const abort = () => {
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if (--operation.waiters === 0) operation.controller.abort();
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};
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clientSignal.addEventListener('abort', abort, { once: true });
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try {
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const value = await operation.promise;
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clientSignal.throwIfAborted();
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return value;
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} finally {
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clientSignal.removeEventListener('abort', abort);
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if (!clientSignal.aborted) operation.waiters--;
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}
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}
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async function upstream(url, signal, image = null, json = false) {
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signal.throwIfAborted();
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const response = await fetchImpl(url, {
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signal,
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redirect: 'error',
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headers: {
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Accept: image
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? 'image/png'
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: json
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? 'application/json'
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: 'application/xml,text/xml',
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},
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});
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if (
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!response.ok ||
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(image &&
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!/^image\/png(?:;|$)/i.test(response.headers.get('content-type') || ''))
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) {
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await response.body?.cancel();
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throw failure('weather_upstream_unavailable');
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}
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const value = image
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? validatePng(
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await readBytesCapped(response, image.maxBytes, signal),
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image.width,
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image.height,
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)
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: await readResponseTextCapped(
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response,
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(json ? 256 : 512) * 1024,
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signal,
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);
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signal.throwIfAborted();
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return value;
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}
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async function getMetadata(product, signal) {
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signal.throwIfAborted();
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const old = metadata.get(product);
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const spec = PRODUCTS[product];
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if (old && now() - old.fetchedAt < (spec.metadataTtlMs ?? 120_000))
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return { ...old, stale: false };
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try {
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if (
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now() - (attempts.get(product) ?? -Infinity) < 30_000 &&
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!operations.has(`metadata:${spec.service}`)
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)
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throw failure('weather_upstream_unavailable');
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attempts.set(product, now());
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const globalRadar = product === 'radar-global';
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const url = globalRadar
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? RAINVIEWER_MANIFEST
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: `${BASE}${spec.service}/ows?service=WMS&version=1.3.0&request=GetCapabilities`;
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const text = await shared(
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`metadata:${spec.service}`,
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(activeSignal) => upstream(url, activeSignal, null, globalRadar),
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signal,
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);
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const value = {
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...(globalRadar
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? parseRainViewerManifest(text)
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: parseWeatherCapabilities(text, product, now())),
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fetchedAt: now(),
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};
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metadata.set(product, value);
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return { ...value, stale: false };
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} catch (error) {
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if (signal.aborted) attempts.delete(product);
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signal.throwIfAborted();
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if (error.status === 429) throw error;
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if (old && now() - old.fetchedAt <= HOUR) return { ...old, stale: true };
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throw failure('weather_metadata_unavailable');
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}
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}
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function rememberTile(key, bytes) {
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if (tiles.has(key)) tileBytes -= tiles.get(key).bytes.length;
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tiles.delete(key);
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while (tiles.size >= 128 || tileBytes + bytes.length > 16 * 1024 * 1024) {
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const oldest = tiles.keys().next().value;
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tileBytes -= tiles.get(oldest).bytes.length;
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tiles.delete(oldest);
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}
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tiles.set(key, { bytes, at: now() });
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tileBytes += bytes.length;
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}
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function describe(product, value) {
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const spec = PRODUCTS[product];
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const time = value?.times.at(-1) ?? null;
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return {
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schemaVersion: 1,
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product,
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title: spec.title,
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coverage: spec.coverage,
|
||
description: spec.description,
|
||
source: spec.source ?? 'NOAA nowCOAST',
|
||
attribution: spec.attribution ?? 'NOAA/NWS/NESDIS nowCOAST',
|
||
bounds: value?.bounds ?? null,
|
||
times: value?.times ?? [],
|
||
latest: time,
|
||
time,
|
||
observedAt: time,
|
||
fetchedAt: value?.fetchedAt ?? null,
|
||
stale: value?.stale ?? true,
|
||
unavailable: !value,
|
||
reason: !value
|
||
? 'Weather imagery unavailable'
|
||
: value.stale
|
||
? 'Cached weather metadata; upstream unavailable'
|
||
: null,
|
||
tileSize: 256,
|
||
maxLevel: spec.maxLevel ?? 6,
|
||
tilingScheme: spec.tilingScheme ?? 'geographic',
|
||
tileTemplate: time
|
||
? `/api/weather/tile?product=${product}&time=${encodeURIComponent(time)}&z={z}&x={x}&y={y}`
|
||
: null,
|
||
imageUrl:
|
||
time && product !== 'radar-global'
|
||
? `/api/weather/image?product=${product}&time=${encodeURIComponent(time)}`
|
||
: null,
|
||
imageSize: { ...spec.image },
|
||
};
|
||
}
|
||
function json(res, status, body, retryAfter = 2) {
|
||
res.writeHead(status, {
|
||
'Content-Type': 'application/json',
|
||
'Cache-Control': 'no-store',
|
||
...(status === 429 ? { 'Retry-After': String(retryAfter) } : {}),
|
||
});
|
||
res.end(JSON.stringify(body));
|
||
}
|
||
async function handler(req, res) {
|
||
const controller = new AbortController();
|
||
const close = () => controller.abort();
|
||
res.once?.('close', close);
|
||
try {
|
||
const url = new URL(req.url, 'http://localhost');
|
||
if (req.method !== 'GET')
|
||
return json(res, 405, { error: 'method_not_allowed' });
|
||
if (!['/manifest', '/tile', '/image'].includes(url.pathname))
|
||
return json(res, 404, { error: 'not_found' });
|
||
const allowed =
|
||
url.pathname === '/manifest'
|
||
? ['product']
|
||
: url.pathname === '/image'
|
||
? ['product', 'time', 'size', 'bbox']
|
||
: ['product', 'time', 'z', 'x', 'y', 'size'];
|
||
if (
|
||
req.url.length > 512 ||
|
||
[...url.searchParams.keys()].some(
|
||
(key) =>
|
||
!allowed.includes(key) || url.searchParams.getAll(key).length !== 1,
|
||
)
|
||
)
|
||
return json(res, 400, { error: 'invalid_weather_query' });
|
||
const product = url.searchParams.get('product');
|
||
if (!Object.hasOwn(PRODUCTS, product))
|
||
return json(res, 400, { error: 'unknown_weather_product' });
|
||
const wholeImage = url.pathname === '/image';
|
||
const globalRadar = product === 'radar-global';
|
||
if (wholeImage && globalRadar)
|
||
throw failure('whole_image_unsupported', 400);
|
||
const detailBox = wholeImage
|
||
? weatherImageBbox(url.searchParams.get('bbox'))
|
||
: null;
|
||
const largest = detailBox ? DETAIL_IMAGE : PRODUCTS[product].image;
|
||
const size =
|
||
url.searchParams.get('size') ??
|
||
(wholeImage ? `${largest.width}x${largest.height}` : '256');
|
||
if (
|
||
wholeImage
|
||
? !IMAGE_SIZES.includes(size) ||
|
||
Number.parseInt(size, 10) > largest.width
|
||
: !(globalRadar ? ['256'] : ['256', '512', '1024']).includes(size)
|
||
)
|
||
throw failure(
|
||
wholeImage
|
||
? 'invalid_weather_image_size'
|
||
: 'invalid_weather_tile_size',
|
||
400,
|
||
);
|
||
if (url.pathname === '/manifest') {
|
||
try {
|
||
const value = await getMetadata(product, controller.signal);
|
||
controller.signal.throwIfAborted();
|
||
return json(res, 200, describe(product, value));
|
||
} catch (error) {
|
||
if (controller.signal.aborted) return;
|
||
if (error.status === 429) throw error;
|
||
return json(res, 200, describe(product, null));
|
||
}
|
||
}
|
||
const coords = wholeImage
|
||
? null
|
||
: ['z', 'x', 'y'].map((key) => url.searchParams.get(key));
|
||
if (coords?.some((value) => !/^(?:0|[1-9]\d{0,2})$/.test(value ?? '')))
|
||
throw failure('invalid_weather_tile', 400);
|
||
const tileBounds = coords
|
||
? globalRadar
|
||
? rainViewerTileCoordinates(...coords.map(Number))
|
||
: weatherTileBounds(...coords.map(Number))
|
||
: null;
|
||
const time = url.searchParams.get('time');
|
||
if (!time || observationTime(time) !== time)
|
||
throw failure('invalid_weather_time', 400);
|
||
const value = await getMetadata(product, controller.signal);
|
||
controller.signal.throwIfAborted();
|
||
if (
|
||
(globalRadar
|
||
? !Object.hasOwn(value.framePaths, time)
|
||
: !value.allowedTimes.includes(time)) ||
|
||
now() - Date.parse(time) > 24 * HOUR
|
||
)
|
||
throw failure('unknown_weather_time', 400);
|
||
if (
|
||
detailBox &&
|
||
(detailBox[0] < value.bounds.west ||
|
||
detailBox[1] < value.bounds.south ||
|
||
detailBox[2] > value.bounds.east ||
|
||
detailBox[3] > value.bounds.north)
|
||
)
|
||
throw failure('invalid_weather_bbox', 400);
|
||
// A single advertised extent keeps NOAA's global reflectance contrast
|
||
// consistent across the image; independently normalized tiles create seams.
|
||
const bbox =
|
||
detailBox ??
|
||
(wholeImage
|
||
? [
|
||
value.bounds.west,
|
||
value.bounds.south,
|
||
value.bounds.east,
|
||
value.bounds.north,
|
||
]
|
||
: tileBounds);
|
||
const [width, height] = wholeImage
|
||
? size.split('x').map(Number)
|
||
: [Number(size), Number(size)];
|
||
const imageShape = {
|
||
width,
|
||
height,
|
||
maxBytes: wholeImage
|
||
? MAX_IMAGE_BYTES
|
||
: Math.max(1024 * 1024, width ** 2 * 4 + 65_536),
|
||
};
|
||
// NOAA WMS capabilities advertise no MaxWidth/MaxHeight. One GetMap
|
||
// returns a whole 4096×2048 extent or window, or a 1024 px tile, without
|
||
// composition. Images are keyed by product, time, size and bbox.
|
||
const key = `${product}:${time}:${wholeImage ? `image:${size}:${bbox.join(',')}` : `tile:${size}:${coords.join('/')}`}`;
|
||
let cached = tiles.get(key);
|
||
if (cached && now() - cached.at <= 24 * HOUR) {
|
||
tiles.delete(key);
|
||
tiles.set(key, cached);
|
||
} else {
|
||
// Never ask nearestValue=1 WMS to silently replace an expired frame.
|
||
if (value.stale) throw failure('weather_metadata_stale');
|
||
if (now() - (tileFailures.get(key) ?? -Infinity) < 30_000)
|
||
throw failure('weather_upstream_unavailable');
|
||
const spec = PRODUCTS[product];
|
||
const upstreamUrl = new URL(
|
||
globalRadar
|
||
? `${RAINVIEWER_TILES}${value.framePaths[time]}/256/${coords.join('/')}/2/1_1.png`
|
||
: `${BASE}${spec.service}/ows`,
|
||
);
|
||
if (!globalRadar)
|
||
upstreamUrl.search = new URLSearchParams({
|
||
service: 'WMS',
|
||
version: '1.1.1',
|
||
request: 'GetMap',
|
||
layers: spec.layer,
|
||
styles: spec.style,
|
||
srs: 'EPSG:4326',
|
||
bbox: bbox.join(','),
|
||
width: String(imageShape.width),
|
||
height: String(imageShape.height),
|
||
format: 'image/png',
|
||
transparent: 'true',
|
||
time,
|
||
}).toString();
|
||
try {
|
||
const bytes = await shared(
|
||
`image:${key}`,
|
||
async (signal) => {
|
||
if (globalRadar) {
|
||
const retryAfter = await admitRainViewerTile.admit(now, {
|
||
signal,
|
||
sleep: rainViewerSleep,
|
||
});
|
||
if (retryAfter)
|
||
throw Object.assign(failure('weather_busy', 429), {
|
||
retryAfter,
|
||
});
|
||
}
|
||
signal.throwIfAborted();
|
||
return upstream(upstreamUrl.href, signal, imageShape);
|
||
},
|
||
controller.signal,
|
||
globalRadar ? 20_000 : 0,
|
||
);
|
||
rememberTile(key, bytes);
|
||
cached = { bytes };
|
||
} catch (error) {
|
||
if (!controller.signal.aborted && error.status !== 429) {
|
||
tileFailures.delete(key);
|
||
tileFailures.set(key, now());
|
||
while (tileFailures.size > 128)
|
||
tileFailures.delete(tileFailures.keys().next().value);
|
||
}
|
||
throw error;
|
||
}
|
||
}
|
||
res.writeHead(200, {
|
||
'Content-Type': 'image/png',
|
||
'Cache-Control': 'public, max-age=86400, immutable',
|
||
'X-Content-Type-Options': 'nosniff',
|
||
});
|
||
res.end(cached.bytes);
|
||
} catch (error) {
|
||
if (!controller.signal.aborted)
|
||
json(
|
||
res,
|
||
error.status === 400 || error.status === 429 ? error.status : 503,
|
||
{
|
||
error:
|
||
error.status === 400 || error.status === 429
|
||
? error.code
|
||
: 'weather_upstream_unavailable',
|
||
},
|
||
error.retryAfter,
|
||
);
|
||
} finally {
|
||
res.removeListener?.('close', close);
|
||
}
|
||
}
|
||
return {
|
||
name: 'weather',
|
||
configureServer({ middlewares }) {
|
||
middlewares.use('/api/weather', handler);
|
||
},
|
||
configurePreviewServer({ middlewares }) {
|
||
middlewares.use('/api/weather', handler);
|
||
},
|
||
};
|
||
}
|