func (p Proxy) lookup(state middleware.State, r *dns.Msg) (*dns.Msg, error) {
var (
reply *dns.Msg
err error
)
for _, upstream := range p.Upstreams {
// allowed bla bla bla TODO(miek): fix full proxy spec from caddy?
start := time.Now()
// Since Select() should give us "up" hosts, keep retrying
// hosts until timeout (or until we get a nil host).
for time.Now().Sub(start) < tryDuration {
host := upstream.Select()
if host == nil {
return nil, errUnreachable
}
atomic.AddInt64(&host.Conns, 1)
// tls+tcp ?
if state.Proto() == "tcp" {
reply, err = middleware.Exchange(p.Client.TCP, r, host.Name)
} else {
reply, err = middleware.Exchange(p.Client.UDP, r, host.Name)
}
atomic.AddInt64(&host.Conns, -1)
if err == nil {
return reply, nil
}
timeout := host.FailTimeout
if timeout == 0 {
timeout = 10 * time.Second
}
atomic.AddInt32(&host.Fails, 1)
go func(host *UpstreamHost, timeout time.Duration) {
time.Sleep(timeout)
atomic.AddInt32(&host.Fails, -1)
}(host, timeout)
}
return nil, errUnreachable
}
return nil, errUnreachable
}
// Report is a plain reporting function that the server can use for REFUSED and other
// queries that are turned down because they don't match any middleware.
func Report(state middleware.State, zone, rcode string, size int, start time.Time) {
if requestCount == nil {
// no metrics are enabled
return
}
// Proto and Family
net := state.Proto()
fam := "1"
if state.Family() == 2 {
fam = "2"
}
typ := state.QType()
requestCount.WithLabelValues(zone, net, fam).Inc()
requestDuration.WithLabelValues(zone).Observe(float64(time.Since(start) / time.Millisecond))
if state.Do() {
requestDo.WithLabelValues(zone).Inc()
}
if _, known := monitorType[typ]; known {
requestType.WithLabelValues(zone, dns.Type(typ).String()).Inc()
} else {
requestType.WithLabelValues(zone, other).Inc()
}
if typ == dns.TypeIXFR || typ == dns.TypeAXFR {
responseTransferSize.WithLabelValues(zone, net).Observe(float64(size))
requestTransferSize.WithLabelValues(zone, net).Observe(float64(state.Size()))
} else {
responseSize.WithLabelValues(zone, net).Observe(float64(size))
requestSize.WithLabelValues(zone, net).Observe(float64(state.Size()))
}
responseRcode.WithLabelValues(zone, rcode).Inc()
}