Golang simply retrier with exponential backoff

retrier.go

package retrier

import (
	"time"

	"github.com/pkg/errors"
)

type backoffRetrier struct {
	initialDelay time.Duration
	maxRetries   int
}

func NewExponentialBackoff(initialDelay time.Duration, maxRetries int) *backoffRetrier {
	return &backoffRetrier{
		initialDelay: initialDelay,
		maxRetries:   maxRetries,
	}
}

func (r *backoffRetrier) Retry(f func(attempt int) error) error {
	var err error
	retryDelay := r.initialDelay
	for attempt := 0; attempt < r.maxRetries; attempt++ {
		err = f(attempt)
		if err == nil {
			return nil
		}
		time.Sleep(retryDelay)
		retryDelay = retryDelay * 2
	}
	return errors.Wrap(err, "max retries reached")
}