Function parseRange

telemetry-dashboard/src/api.ts:95–114

* The range every endpoint shares. Absent params default to the last 30 days * ending today so a bare `curl /api/summary` still answers something sensible; * the dashboard itself always sends both, anchored on /api/meta's latest day so * no chart ends on a day the nightly rollup has not written y

(url: URL)

 * no chart ends on a day the nightly rollup has not written yet.
 */
function parseRange(url: URL): Range | ApiResult {
  const rawTo = url.searchParams.get('to');
  const rawFrom = url.searchParams.get('from');

  if (rawTo !== null && !isValidDay(rawTo)) return fail('to must be YYYY-MM-DD');
  if (rawFrom !== null && !isValidDay(rawFrom)) return fail('from must be YYYY-MM-DD');

  const to = rawTo ?? utcDay(Date.now());
  const from = rawFrom ?? addDays(to, -(DEFAULT_RANGE_DAYS - 1));
  if (from > to) return fail('from must not be after to');

  const requested = daysApart(from, to) + 1;
  const clamped = requested > MAX_RANGE_DAYS;
  return {
    from: clamped ? addDays(to, -(MAX_RANGE_DAYS - 1)) : from,
    to,
    days: clamped ? MAX_RANGE_DAYS : requested,
    clamped,
  };
}

const isApiResult = (v: Range | ApiResult): v is ApiResult => 'body' in v;