Kazuma
51 lines
1.7 KiB
TypeScript
51 lines
1.7 KiB
TypeScript
import { DatabaseConnection } from '../shared/db/index';
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import { QueryBuilder } from '../shared/utils/QueryBuilder';
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/**
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* The tracked-ticker universe (FREE-DATA-STACK §4.1):
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* watchlist ∪ holdings ∪ tickers screened in the last 30 days.
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*
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* This is the news pipeline's first and biggest filter — stories about
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* tickers outside the universe are never stored. Cached for 10 minutes;
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* the universe changes slowly.
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*/
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export class UniverseProvider {
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private static readonly CACHE_TTL_MS = 10 * 60 * 1000;
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private static readonly SNAPSHOT_LOOKBACK_DAYS = 30;
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private cache: { universe: Set<string>; expiresAt: number } = {
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universe: new Set(),
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expiresAt: 0,
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};
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constructor(private readonly db: DatabaseConnection) {}
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getUniverse(): Set<string> {
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if (Date.now() < this.cache.expiresAt) return this.cache.universe;
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const sinceDay = new Date(
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Date.now() - UniverseProvider.SNAPSHOT_LOOKBACK_DAYS * 24 * 60 * 60 * 1000,
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)
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.toISOString()
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.slice(0, 10);
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const tickers = new Set<string>();
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const add = (rows: { ticker: string }[]) =>
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rows.forEach((r) => tickers.add(r.ticker.toUpperCase()));
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add(this.db.all(new QueryBuilder('UNIVERSE_QUERIES.DISTINCT_WATCHLIST_TICKERS')));
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add(this.db.all(new QueryBuilder('UNIVERSE_QUERIES.DISTINCT_HOLDING_TICKERS')));
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add(
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this.db.all(new QueryBuilder('UNIVERSE_QUERIES.DISTINCT_SNAPSHOT_TICKERS_SINCE', [sinceDay])),
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);
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this.cache = { universe: tickers, expiresAt: Date.now() + UniverseProvider.CACHE_TTL_MS };
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return tickers;
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}
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/** Force next getUniverse() to re-read (e.g. after a watchlist change). */
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invalidate(): void {
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this.cache.expiresAt = 0;
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}
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}
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