1await retry.async(fn, {
2    retryIf: error => error.name === 'NetworkError',
3});

1await retry.async(fn, {
2    fallback: async () => backupOperation(),
3    // Or multiple fallbacks
4    fallback: [async () => primaryBackup(), async () => secondaryBackup()],
5});

Backoff is a technique that progressively increases the delay between retry attempts. This helps prevent overwhelming the system being called and allows it time to recover from any issues. Like gradually stepping back when something's not working, rather than continuously trying at the same rate.

1await retry.async(fn, {
2    backoffStrategy: 'exponential', // 1s → 2s → 4s (default)
3    backoffStrategy: 'linear', // 1s → 2s → 3s
4    backoffStrategy: 'aggressive', // 1s → 3s → 9s
5    backoffStrategy: 'fixed', // 1s → 1s → 1s
6});

Jitter adds randomness to retry delays to prevent multiple clients from retrying at exactly the same time. This is particularly important in distributed systems where synchronized retries could cause "thundering herd" problems - where many clients hit a service simultaneously after a failure.

1await retry.async(fn, {
2    jitterStrategy: 'full', // Random between 0 and delay (default)
3    jitterStrategy: 'equal', // Random between delay/2 and delay*1.5
4    jitterStrategy: 'decorrelated', // Independent random delays
5    jitterStrategy: 'none', // Exact delays
6});

1const controller = new AbortController();
2
3await retry.async(fn, {
4    signal: controller.signal,
5});
6
7// Cancel retries
8controller.abort();

1await retry.fetch('https://api.example.com/data', {
2    retry: {
3        retryStatusCodes: [408, 429, 500, 502, 503, 504], // HTTP status codes that will trigger a retry
4        retryNetworkErrors: true, // Whether to retry on network/connection errors
5    },
6});

retry.async

1function async<T>(
2    fn: () => Promise<T>,
3    options?: RetryAsyncOptions<T>,
4): Promise<RetryAsyncResult<T>>;
5
6interface RetryAsyncResult<T> {
7    data: T; // The result of the function
8    attempts: number; // The number of attempts made
9    totalTime: number; // The total time taken for all attempts
10    errors: Error[]; // The errors that occurred during the attempts
11}

retry.fetch

1function fetch(
2    input: RequestInfo | URL,
3    init?: RequestInit & {
4        retry?: RetryFetchOptions;
5    },
6): Promise<RetryFetchResult>;
7
8interface RetryFetchResult {
9    response: Response; // The response from the fetch request
10    attempts: number; // The number of attempts made
11    totalTime: number; // The total time taken for all attempts
12    errors: Error[]; // The errors that occurred during the attempts
13}

Error Types

1import {
2    MaxRetriesExceededError, // Thrown when max retries are exceeded
3    RetryAbortedError, // Thrown when the operation is aborted
4    RetryConditionFailedError, // Thrown when the retry condition check fails
5    RetryOperationError, // Base error for all retry operations
6} from 'nice-retry';