app/lib/search/ask-twins.mjs

Functions

Imports

It imports no other module of this repo. Imported by app/lib/search/ask.server.ts.

Source

1// A failed key still joins keys: the caller prunes every key it is not given, so leaving it out would
2// turn a transient into a deletion. Failures are returned so the sync report can refuse to converge.
3
4export const TWIN_ATTEMPTS = 3;
5
6const TWIN_BACKOFF_MS = 500;
7
8/**
9 * @template T
10 * @param {() => Promise<T>} fn
11 * @param {{ attempts?: number, backoffMs?: number, sleep?: (ms: number) => Promise<void> }} [opts]
12 * @returns {Promise<T>}
13 */
14export async function withRetry(fn, opts = {}) {
15  const attempts = opts.attempts ?? TWIN_ATTEMPTS;
16  const backoffMs = opts.backoffMs ?? TWIN_BACKOFF_MS;
17  const sleep = opts.sleep ?? ((ms) => new Promise((r) => setTimeout(r, ms)));
18  /** @type {unknown} */
19  let last;
20  for (let attempt = 1; attempt <= attempts; attempt += 1) {
21    try {
22      return await fn();
23    } catch (error) {
24      last = error;
25      if (attempt < attempts) await sleep(backoffMs * 2 ** (attempt - 1));
26    }
27  }
28  throw last;
29}
30
31/**
32 * @param {Array<{ key: string, path: string }>} twins the item key and the asset path of each twin
33 * @param {{
34 *   fetchText: (path: string) => Promise<string>,
35 *   upload: (key: string, body: string) => Promise<unknown>,
36 *   log?: (...args: unknown[]) => void,
37 *   attempts?: number,
38 *   backoffMs?: number,
39 *   sleep?: (ms: number) => Promise<void>,
40 * }} io `fetchText` throws on a missing or unreadable twin
41 * @returns {Promise<{ keys: string[], failed: Array<{ key: string, error: string }> }>}
42 */
43export async function uploadTwins(twins, io) {
44  const retry = { attempts: io.attempts, backoffMs: io.backoffMs, sleep: io.sleep };
45  const log = io.log ?? console.error;
46  const keys = [];
47  const failed = [];
48  for (const { key, path } of twins) {
49    keys.push(key);
50    try {
51      const body = await withRetry(() => io.fetchText(path), retry);
52      await withRetry(() => io.upload(key, body), retry);
53    } catch (error) {
54      const message = error instanceof Error ? `${error.name}: ${error.message}` : String(error);
55      log("ask twin upload failed after retries", key, message);
56      failed.push({ key, error: message });
57    }
58  }
59  return { keys, failed };
60}