Files
privacy.sexy/tests/checks/external-urls/StatusChecker/ExponentialBackOffRetryHandler.ts
undergroundwires 949fac1a7c Refactor to enforce strictNullChecks
This commit applies `strictNullChecks` to the entire codebase to improve
maintainability and type safety. Key changes include:

- Remove some explicit null-checks where unnecessary.
- Add necessary null-checks.
- Refactor static factory functions for a more functional approach.
- Improve some test names and contexts for better debugging.
- Add unit tests for any additional logic introduced.
- Refactor `createPositionFromRegexFullMatch` to its own function as the
  logic is reused.
- Prefer `find` prefix on functions that may return `undefined` and
  `get` prefix for those that always return a value.
2023-11-12 22:54:00 +01:00

52 lines
1.7 KiB
TypeScript

import { sleep } from '@/infrastructure/Threading/AsyncSleep';
import { IUrlStatus } from './IUrlStatus';
const DefaultBaseRetryIntervalInMs = 5 /* sec */ * 1000;
export async function retryWithExponentialBackOff(
action: () => Promise<IUrlStatus>,
baseRetryIntervalInMs: number = DefaultBaseRetryIntervalInMs,
currentRetry = 1,
): Promise<IUrlStatus> {
const maxTries = 3;
const status = await action();
if (shouldRetry(status)) {
if (currentRetry <= maxTries) {
const exponentialBackOffInMs = getRetryTimeoutInMs(currentRetry, baseRetryIntervalInMs);
// tslint:disable-next-line: no-console
console.log(`Retrying (${currentRetry}) in ${exponentialBackOffInMs / 1000} seconds`, status);
await sleep(exponentialBackOffInMs);
return retryWithExponentialBackOff(action, baseRetryIntervalInMs, currentRetry + 1);
}
}
return status;
}
function shouldRetry(status: IUrlStatus) {
if (status.error) {
return true;
}
if (status.code === undefined) {
return true;
}
return isTransientError(status.code)
|| status.code === 429; // Too Many Requests
}
function isTransientError(statusCode: number) {
return statusCode >= 500 && statusCode <= 599;
}
function getRetryTimeoutInMs(
currentRetry: number,
baseRetryIntervalInMs: number = DefaultBaseRetryIntervalInMs,
) {
const retryRandomFactor = 0.5; // Retry intervals are between 50% and 150%
// of the exponentially increasing base amount
const minRandom = 1 - retryRandomFactor;
const maxRandom = 1 + retryRandomFactor;
const randomization = (Math.random() * (maxRandom - minRandom)) + maxRandom;
const exponential = 2 ** (currentRetry - 1);
return Math.ceil(exponential * baseRetryIntervalInMs * randomization);
}