// Instrumentation returns a Decorator which instruments an Exchanger with the given
// counter.
func Instrumentation(c logging.Counter) Decorator {
return func(ex Exchanger) Exchanger {
return Func(func(m *dns.Msg, a string) (*dns.Msg, time.Duration, error) {
defer c.Inc()
return ex.Exchange(m, a)
})
}
}
// Instrumentation returns a Decorator which instruments an Exchanger with the given
// counters.
func Instrumentation(total, success, failure logging.Counter) Decorator {
return func(ex Exchanger) Exchanger {
return Func(func(m *dns.Msg, a string) (r *dns.Msg, rtt time.Duration, err error) {
defer func() {
if total.Inc(); err != nil {
failure.Inc()
} else {
success.Inc()
}
}()
return ex.Exchange(m, a)
})
}
}