coredns/middleware/etcd/handler.go
2016-03-22 11:04:56 +00:00

72 lines
1.7 KiB
Go

package etcd
import (
"github.com/miekg/coredns/middleware"
"github.com/miekg/dns"
"golang.org/x/net/context"
)
func (e Etcd) ServeDNS(ctx context.Context, w dns.ResponseWriter, r *dns.Msg) (int, error) {
println("ETCD MIDDLEWARE HIT")
state := middleware.State{W: w, Req: r}
zone := middleware.Zones(e.Zones).Matches(state.Name())
if zone == "" {
return e.Next.ServeDNS(ctx, w, r)
}
m := state.AnswerMessage()
m.Authoritative, m.RecursionAvailable, m.Compress = true, true, true
var (
records, extra []dns.RR
err error
)
switch state.Type() {
case "A":
records, err = e.A(zone, state, nil)
case "AAAA":
records, err = e.AAAA(zone, state, nil)
case "TXT":
records, err = e.TXT(zone, state)
case "CNAME":
records, err = e.CNAME(zone, state)
case "MX":
records, extra, err = e.MX(zone, state)
case "SRV":
records, extra, err = e.SRV(zone, state)
default:
// rwrite and return
// Nodata response
// also catch other types, so that they return NODATA
return 0, nil
}
if isEtcdNameError(err) {
NameError(zone, state)
return dns.RcodeNameError, nil
}
if err != nil {
// TODO(miek): err or nil in this case?
return dns.RcodeServerFailure, err
}
if len(records) > 0 {
m.Answer = append(m.Answer, records...)
}
if len(extra) > 0 {
m.Extra = append(m.Extra, extra...)
}
state.W.WriteMsg(m)
return 0, nil
}
// NameError writes a name error to the client.
func NameError(zone string, state middleware.State) {
m := new(dns.Msg)
m.SetRcode(state.Req, dns.RcodeNameError)
m.Ns = []dns.RR{SOA(zone)}
state.W.WriteMsg(m)
}
// NoData write a nodata response to the client.
func NoData(zone string, state middleware.State) {
// TODO(miek): write it
}