remove unused code (#774)

middleware/kubernetes/lookup.go

@@ -1,54 +0,0 @@
-package kubernetes
-
-import (
-	"fmt"
-	"net"
-
-	"github.com/coredns/coredns/middleware/etcd/msg"
-	"github.com/coredns/coredns/middleware/pkg/dnsutil"
-	"github.com/coredns/coredns/request"
-
-	"github.com/miekg/dns"
-)
-
-func (k Kubernetes) records(state request.Request, exact bool) ([]msg.Service, error) {
-	r, err := k.parseRequest(state.Name(), state.QType())
-	if err != nil {
-		return nil, err
-	}
-	services, err := k.Entries(r)
-	if err != nil {
-		return nil, err
-	}
-	services = msg.Group(services)
-	return services, nil
-}
-
-// PTR Record returns PTR records from kubernetes.
-func (k Kubernetes) PTR(zone string, state request.Request) ([]dns.RR, error) {
-	reverseIP := dnsutil.ExtractAddressFromReverse(state.Name())
-	if reverseIP == "" {
-		return nil, fmt.Errorf("does not support reverse lookup for %s", state.QName())
-	}
-
-	records := make([]dns.RR, 1)
-	services, err := k.records(state, false)
-	if err != nil {
-		return nil, err
-	}
-
-	for _, serv := range services {
-		ip := net.ParseIP(serv.Host)
-		if reverseIP != serv.Host {
-			continue
-		}
-		switch {
-		case ip.To4() != nil:
-			records = append(records, serv.NewPTR(state.QName(), ip.To4().String()))
-			break
-		case ip.To4() == nil:
-			// nodata?
-		}
-	}
-	return records, nil
-}