Versie 0.2.0

server/data/bus.js

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+// Generated, do not edit. sha256:8bd40013f30173c4395fe482f251f8d822b2781e68ecf02d880e6748f3e5817a
+import * as db from '../db.js';
+import { CONFIG } from '../../shared/config.js';
+import { nowIso } from './_shared.js';
+import { takeChanges } from './_events.js';
+
+export function flushChanges() {
+  const namen = takeChanges();
+  if (!namen.length) return [];
+  const at = nowIso();
+  for (const naam of namen) {
+    db.run(`INSERT INTO BusSignal (name, occurredAt) VALUES (?,?)`, [naam, at]);
+  }
+  pruneChanges();
+  return namen;
+}
+
+export function pruneChanges(uren = CONFIG.BUS.RETENTION_HOURS) {
+  const grens = new Date(Date.now() - Math.max(1, Number(uren) || CONFIG.BUS.RETENTION_HOURS) * 3600_000)
+    .toISOString();
+  const r = db.one(`SELECT COUNT(*) AS n FROM BusSignal WHERE occurredAt < ?`, [grens]);
+  const aantal = r ? r.n : 0;
+  if (aantal) db.run(`DELETE FROM BusSignal WHERE occurredAt < ?`, [grens]);
+  return aantal;
+}
+
+export function changesSince(cursor) {
+  const vanaf = Number.isInteger(cursor) && cursor >= 0 ? cursor : null;
+  const grens = db.one(`SELECT MIN(id) AS eerste, MAX(id) AS laatste FROM BusSignal`);
+  const laatste = grens && grens.laatste != null ? grens.laatste : (vanaf ?? 0);
+  if (vanaf === null) return { cursor: laatste, names: [], reset: false };
+
+  const eerste = grens ? grens.eerste : null;
+  if (eerste != null && vanaf < eerste - 1) return { cursor: laatste, names: [], reset: true };
+
+  const rijen = db.all(`SELECT DISTINCT name FROM BusSignal WHERE id > ? ORDER BY name`, [vanaf]);
+  return { cursor: laatste, names: rijen.map(r => r.name), reset: false };
+}