Package retry provides a reliable, simple way to retry operations.
go get -u github.com/AdamSLevy/retry
// The provided policies can be composed to a custom Policy.
policy := retry.LimitTotal{25 * time.Minute,
retry.LimitAttempts{10,
retry.Max{10 * time.Minute,
retry.Randomize{.5,
retry.Exponential{5 * time.Second, 2}}}}}
// A notify function is called before each wait period.
notify := func(err error, attempt uint, d time.Duration) {
fmt.Printf("Attempt %v returned %v. Retrying in %v...\n",
attempt, err, d)
}
// A filter function can be used to omit or wrap certain errors to tell
// Run to stop immediately.
filter := func(err error) error {
if errors.Is(err, errors.New("unrecoverable err")) {
return retry.ErrorStop(err)
}
return err
}
// A context.Context may be passed so that waits can be canceled.
var ctx = context.TODO()
err := retry.Run(ctx, policy, filter, notify, func() error {
return tryWork(ctx)
})
if err != nil {
return
}
This package was inspired by github.com/cenkalti/backoff but improves on the design by providing Policy types that are composable, re-usable and safe for repeated or concurrent calls to Run.