executeWithRetry<T> method

Future<T> executeWithRetry<T>(RetryPolicy policy, Future<T> action(), { void onAttempt(int attempt)?, FutureOr<void> onRetry(int attempt, Object error)?, Future<void> delayFn(Duration delay)?, })

Executes action with retry logic according to policy.

Returns the result on success. Throws the last exception if all attempts are exhausted.

onAttempt is called before each attempt with the 1-based attempt number. onRetry is called before each retry delay with the attempt number and error. delayFn is injectable for testing (avoids real waits).

Implementation

Future<T> executeWithRetry<T>(
  RetryPolicy policy,
  Future<T> Function() action, {
  void Function(int attempt)? onAttempt,
  FutureOr<void> Function(int attempt, Object error)? onRetry,
  Future<void> Function(Duration delay)? delayFn,
}) async {
  final effectiveDelay = delayFn ?? (Duration d) => Future<void>.delayed(d);
  var attempt = 1;

  while (true) {
    onAttempt?.call(attempt);
    try {
      return await action();
    } catch (e) {
      if (!shouldRetry(policy, attempt)) {
        rethrow;
      }
      await onRetry?.call(attempt, e);
      final delay = calculateDelay(policy, attempt);
      await effectiveDelay(delay);
      attempt++;
    }
  }
}