Retry for dart

This package provides an easy way to retry asynchronous functions. This is often useful to avoid crashing on intermittent errors such as broken connections or temporarily overloaded servers.

Disclaimer: This is not an officially supported Google product.

Using retry

For simple retry logic with exponential back-off use the retry function provided by this package.

import 'package:retry/retry.dart';

final response = await retry(
  // Make a GET request
  () => http.get('https://google.com').timeout(Duration(seconds: 5)),
  // Retry on SocketException or TimeoutException
  retryIf: (e) => e is SocketException || e is TimeoutException,
);
print(response.body);

Defaults to 8 attempts, sleeping as following after 1st, 2nd, 3rd, ..., 7th attempt:

  1. 400 ms +/- 25%
  2. 800 ms +/- 25%
  3. 1600 ms +/- 25%
  4. 3200 ms +/- 25%
  5. 6400 ms +/- 25%
  6. 12800 ms +/- 25%
  7. 25600 ms +/- 25%

Using RetryOptions

This package provides RetryOptions which defined how many times to retry an function and how long to sleep between retries.

final r = RetryOptions(attempts: 8);
final response = await r.retry(
  // Make a GET request
  () => http.get('https://google.com').timeout(Duration(seconds: 5)),
  // Retry on SocketException or TimeoutException
  retryIf: (e) => e is SocketException || e is TimeoutException,
);
print(response.body);

Libraries

retry
Retry asynchronous functions with exponential backoff. [...]