// WithBackoff implements retry with exponential backoff using
// the supplied options as parameters. When fn returns Continue
// and the number of retry attempts haven't been exhausted, fn is
// retried. When fn returns Break, retry ends. As a special case,
// if fn returns Reset, the backoff and retry count are reset to
// starting values and the next retry occurs immediately. Returns an
// error if the maximum number of retries is exceeded or if the fn
// returns an error.
func WithBackoff(opts Options, fn func() (Status, error)) error {
backoff := opts.Backoff
tag := opts.Tag
if tag == "" {
tag = "invocation"
}
for count := 1; true; count++ {
status, err := fn()
if status == Break {
return err
}
if err != nil && (!opts.UseV1Info || log.V(1) == true) {
log.InfoDepth(1, tag, " failed an iteration: ", err)
}
var wait time.Duration
if status == Reset {
backoff = opts.Backoff
wait = 0
count = 0
if !opts.UseV1Info || log.V(1) == true {
log.InfoDepth(1, tag, " failed; retrying immediately")
}
} else {
if opts.MaxAttempts > 0 && count >= opts.MaxAttempts {
return &MaxAttemptsError{opts.MaxAttempts}
}
if !opts.UseV1Info || log.V(1) == true {
log.InfoDepth(1, tag, " failed; retrying in ", backoff)
}
wait = backoff + time.Duration(rand.Float64()*float64(backoff.Nanoseconds())*retryJitter)
// Increase backoff for next iteration.
backoff = time.Duration(float64(backoff) * opts.Constant)
if backoff > opts.MaxBackoff {
backoff = opts.MaxBackoff
}
}
// Wait before retry.
select {
case <-time.After(wait):
// Continue retrying.
case <-opts.Stopper.ShouldStop():
return util.Errorf("%s retry loop stopped", tag)
}
}
return nil
}
func (r *raftLogger) Infof(format string, v ...interface{}) {
if log.V(1) {
s := r.prependContext(format, v)
log.InfoDepth(1, s)
}
}
func (*raftLogger) Info(v ...interface{}) {
if log.V(1) {
log.InfoDepth(1, v...)
}
}
func (*raftLogger) Debug(v ...interface{}) {
if log.V(2) {
log.InfoDepth(1, v...)
}
}
func (*raftLogger) Infof(format string, v ...interface{}) {
if log.V(1) {
s := fmt.Sprintf(format, v...)
log.InfoDepth(1, s)
}
}