hope-events/backend/src/utils/errorCounter.js

// Server errors (5xx responses) in the last 24 hours, for the Hub heartbeat. In memory per
// process: a restart starts again from zero, which is fine for spotting a spike.
const WINDOW_MS = 24 * 60 * 60 * 1000;
const MAX_KEPT = 10000;
let times = [];

function recordError(now = Date.now()) {
  times.push(now);
  if (times.length > MAX_KEPT) times = times.slice(-MAX_KEPT);
}

function countLast24h(now = Date.now()) {
  times = times.filter(t => now - t < WINDOW_MS);
  return times.length;
}

module.exports = { recordError, countLast24h };