Press n or j to go to the next uncovered block, b, p or k for the previous block.
| 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 | 45x 45x 45x 45x 45x 42x 13x 13x 29x 17x 17x 2x 2x 2x 2x 15x 45x | /**
* @module imf/transport/fetch-with-retry
* @description Shared HTTP fetch primitive for IMF transport layers.
*
* Datamapper (unauth) and SDMX (auth) differ in headers but share the
* exact same timeout + retry + error-classification machinery. Keep
* that machinery here so the transport modules can stay thin and
* focused on URL building / envelope shape.
*
* @author Hack23 AB
* @license Apache-2.0
*/
import { ImfHttpError } from '../errors/http-error.js';
import { calculateRetryDelay, isRetryableError } from './retry.js';
export interface FetchWithRetryOptions {
readonly timeout: number;
readonly maxRetries: number;
readonly userAgent: string;
readonly extraHeaders?: Record<string, string>;
}
/**
* GET `url` with exponential back-off retry on 429 / 5xx / network
* errors. Throws {@link ImfHttpError} on non-OK responses.
*
* The `extraHeaders` map is the auth boundary: Datamapper transport
* passes `{}` (no subscription key) and SDMX transport injects the
* `Ocp-Apim-Subscription-Key` header here. This helper itself does
* NOT validate the contents of `extraHeaders` — the
* "Datamapper transport never carries an SDMX subscription key"
* convention is enforced at the call sites (see
* `scripts/imf/transport/datamapper.ts`) and asserted by the
* "IMF SDMX subscription key auth boundary" static-source scan in
* `tests/imf/refactor-invariants.test.ts`.
*/
export async function fetchWithRetry(
url: string,
options: FetchWithRetryOptions,
attempt = 0,
): Promise<unknown> {
const { timeout, maxRetries, userAgent, extraHeaders = {} } = options;
const controller = new AbortController();
const timeoutId = setTimeout(() => controller.abort(), timeout);
try {
const response = await fetch(url, {
signal: controller.signal,
headers: {
Accept: 'application/json',
'User-Agent': userAgent,
...extraHeaders,
},
});
if (!response.ok) {
const sentSubscriptionKey = 'Ocp-Apim-Subscription-Key' in extraHeaders;
throw new ImfHttpError(response, url, sentSubscriptionKey);
}
return await response.json();
} catch (error) {
const retryAfterHeader = error instanceof ImfHttpError ? error.retryAfterHeader : undefined;
if (attempt < maxRetries && isRetryableError(error)) {
const delay = calculateRetryDelay(attempt, retryAfterHeader);
clearTimeout(timeoutId);
await new Promise((resolve) => setTimeout(resolve, delay));
return fetchWithRetry(url, options, attempt + 1);
}
throw error;
} finally {
clearTimeout(timeoutId);
}
}
|