renovate/lib/util/http/retry-after.ts

116 lines
2.8 KiB
TypeScript

import { setTimeout } from 'timers/promises';
import { RequestError } from 'got';
import { DateTime } from 'luxon';
import { logger } from '../../logger';
import { parseUrl } from '../url';
import type { Task } from './types';
const hostDelays = new Map<string, Promise<unknown>>();
const maxRetries = 2;
/**
* Given a task that returns a promise, retry the task if it fails with a
* 429 Too Many Requests or 403 Forbidden response, using the Retry-After
* header to determine the delay.
*
* For response codes other than 429 or 403, or if the Retry-After header
* is not present or invalid, the task is not retried, throwing the error.
*/
export async function wrapWithRetry<T>(
task: Task<T>,
url: string,
getRetryAfter: (err: unknown) => number | null,
maxRetryAfter: number,
): Promise<T> {
const key = parseUrl(url)?.host ?? url;
let retries = 0;
for (;;) {
try {
await hostDelays.get(key);
hostDelays.delete(key);
return await task();
} catch (err) {
const delaySeconds = getRetryAfter(err);
if (delaySeconds === null) {
throw err;
}
if (retries === maxRetries) {
logger.debug(
`Retry-After: reached maximum retries (${maxRetries}) for ${url}`,
);
throw err;
}
if (delaySeconds > maxRetryAfter) {
logger.debug(
`Retry-After: delay ${delaySeconds} seconds exceeds maxRetryAfter ${maxRetryAfter} seconds for ${url}`,
);
throw err;
}
logger.debug(
`Retry-After: will retry ${url} after ${delaySeconds} seconds`,
);
const delay = Promise.all([
hostDelays.get(key),
setTimeout(1000 * delaySeconds),
]);
hostDelays.set(key, delay);
retries += 1;
}
}
}
export function getRetryAfter(err: unknown): number | null {
if (!(err instanceof RequestError)) {
return null;
}
if (!err.response) {
return null;
}
if (err.response.statusCode < 400 || err.response.statusCode >= 500) {
logger.debug(
{ url: err.response.url },
`Retry-After: unexpected status code ${err.response.statusCode}`,
);
return null;
}
const retryAfter = err.response.headers['retry-after']?.trim();
if (!retryAfter) {
return null;
}
const date = DateTime.fromHTTP(retryAfter);
if (date.isValid) {
const seconds = Math.floor(date.diffNow('seconds').seconds);
if (seconds < 0) {
logger.debug(
{ url: err.response.url, retryAfter },
'Retry-After: date in the past',
);
return null;
}
return seconds;
}
const seconds = parseInt(retryAfter, 10);
if (!Number.isNaN(seconds) && seconds >= 0) {
return seconds;
}
logger.debug(
{ url: err.response.url, retryAfter },
'Retry-After: unsupported format',
);
return null;
}