more etcd stuff

middleware/etcd/handler.go

@@ -0,0 +1,105 @@
+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}
+
+	m := state.AnswerMessage()
+	m.Authoritative = true
+	m.RecursionAvailable = true
+	m.Compress = true
+
+	return 0, nil
+}
+
+// only needs state and current zone name we are auth for.
+/*
+func (s *server) ServeDNS(w dns.ResponseWriter, req *dns.Msg) {
+
+	q := req.Question[0]
+	name := strings.ToLower(q.Name)
+
+	switch q.Qtype {
+	case dns.TypeNS:
+		records, extra, err := s.NSRecords(q, s.config.dnsDomain)
+		if isEtcdNameError(err, s) {
+			m = s.NameError(req)
+			return
+		}
+		m.Answer = append(m.Answer, records...)
+		m.Extra = append(m.Extra, extra...)
+	case dns.TypeA, dns.TypeAAAA:
+		records, err := s.AddressRecords(q, name, nil, bufsize, dnssec, false)
+		if isEtcdNameError(err, s) {
+			m = s.NameError(req)
+			return
+		}
+		m.Answer = append(m.Answer, records...)
+	case dns.TypeTXT:
+		records, err := s.TXTRecords(q, name)
+		if isEtcdNameError(err, s) {
+			m = s.NameError(req)
+			return
+		}
+		m.Answer = append(m.Answer, records...)
+	case dns.TypeCNAME:
+		records, err := s.CNAMERecords(q, name)
+		if isEtcdNameError(err, s) {
+			m = s.NameError(req)
+			return
+		}
+		m.Answer = append(m.Answer, records...)
+	case dns.TypeMX:
+		records, extra, err := s.MXRecords(q, name, bufsize, dnssec)
+		if isEtcdNameError(err, s) {
+			m = s.NameError(req)
+			return
+		}
+		m.Answer = append(m.Answer, records...)
+		m.Extra = append(m.Extra, extra...)
+	default:
+		fallthrough // also catch other types, so that they return NODATA
+	case dns.TypeSRV:
+		records, extra, err := s.SRVRecords(q, name, bufsize, dnssec)
+		if err != nil {
+			if isEtcdNameError(err, s) {
+				m = s.NameError(req)
+				return
+			}
+			logf("got error from backend: %s", err)
+			if q.Qtype == dns.TypeSRV { // Otherwise NODATA
+				m = s.ServerFailure(req)
+				return
+			}
+		}
+		// if we are here again, check the types, because an answer may only
+		// be given for SRV. All other types should return NODATA, the
+		// NXDOMAIN part is handled in the above code. TODO(miek): yes this
+		// can be done in a more elegant manor.
+		if q.Qtype == dns.TypeSRV {
+			m.Answer = append(m.Answer, records...)
+			m.Extra = append(m.Extra, extra...)
+		}
+	}
+
+	if len(m.Answer) == 0 { // NODATA response
+		m.Ns = []dns.RR{s.NewSOA()}
+		m.Ns[0].Header().Ttl = s.config.MinTtl
+	}
+}
+
+// etcNameError checks if the error is ErrorCodeKeyNotFound from etcd.
+func isEtcdNameError(err error, s *server) bool {
+	if e, ok := err.(etcd.Error); ok && e.Code == etcd.ErrorCodeKeyNotFound {
+		return true
+	}
+	return false
+}
+*/