Function RetryLoop

base/util.go:451–489

(ctx context.Context, description string, worker RetryWorker[T], sleeper RetrySleeper)

}

func RetryLoop[T any](ctx context.Context, description string, worker RetryWorker[T], sleeper RetrySleeper) (error, T) {

	numAttempts := 1

	for {
		shouldRetry, err, value := worker()
		if !shouldRetry {
			if err != nil {
				return err, *new(T)
			}
			return nil, value
		}
		shouldContinue, sleepMs := sleeper(numAttempts)
		if !shouldContinue {
			if err == nil {
				err = NewRetryTimeoutError(description, numAttempts)
			}
			WarnfCtx(ctx, "RetryLoop for %v giving up after %v attempts", description, numAttempts)
			return err, value
		}
		DebugfCtx(ctx, KeyAll, "RetryLoop retrying %v after %v ms.", description, sleepMs)

		select {
		case <-ctx.Done():
			verb := "closed"
			ctxErr := ctx.Err()
			if errors.Is(ctxErr, context.Canceled) {
				verb = "canceled"
			} else if errors.Is(ctxErr, context.DeadlineExceeded) {
				verb = "timed out"
			}
			return fmt.Errorf("Retry loop for %v %s based on context: %w", description, verb, context.Cause(ctx)), *new(T)
		case <-time.After(time.Millisecond * time.Duration(sleepMs)):
		}

		numAttempts += 1

	}
}

// A version of RetryLoop that returns a strongly typed cas as uint64, to avoid interface conversion overhead for
// high throughput operations.