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Cleanup: put middleware helper functions in pkgs (#245)

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Move all (almost all) Go files in middleware into their
own packages. This makes for better naming and discoverability.

Lot of changes elsewhere to make this change.

The middleware.State was renamed to request.Request which is better,
but still does not cover all use-cases. It was also moved out middleware
because it is used by `dnsserver` as well.

A pkg/dnsutil packages was added for shared, handy, dns util functions.

All normalize functions are now put in normalize.go
This commit is contained in:
Miek Gieben 2016-09-07 11:10:16 +01:00 • committed by GitHub
parent 684330fd28
commit d1f17fa7e0
90 changed files with 680 additions and 1037 deletions
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80
middleware/kubernetes/lookup.go
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@ -4,21 +4,17 @@ import (
"fmt"
"math"
"net"
"strings"
"time"
"github.com/miekg/coredns/middleware"
"github.com/miekg/coredns/middleware/kubernetes/msg"
"github.com/miekg/coredns/middleware/pkg/dnsutil"
"github.com/miekg/coredns/request"
"github.com/miekg/dns"
)
const (
// arpaSuffix is the standard suffix for PTR IP reverse lookups.
arpaSuffix = ".in-addr.arpa."
)
func (k Kubernetes) records(state middleware.State, exact bool) ([]msg.Service, error) {
func (k Kubernetes) records(state request.Request, exact bool) ([]msg.Service, error) {
services, err := k.Records(state.Name(), exact)
if err != nil {
return nil, err
@ -28,7 +24,7 @@ func (k Kubernetes) records(state middleware.State, exact bool) ([]msg.Service,
return services, nil
}
func (k Kubernetes) A(zone string, state middleware.State, previousRecords []dns.RR) (records []dns.RR, err error) {
func (k Kubernetes) A(zone string, state request.Request, previousRecords []dns.RR) (records []dns.RR, err error) {
services, err := k.records(state, false)
if err != nil {
return nil, err
@ -49,11 +45,11 @@ func (k Kubernetes) A(zone string, state middleware.State, previousRecords []dns
// don't add it, and just continue
continue
}
if isDuplicateCNAME(newRecord, previousRecords) {
if dnsutil.DuplicateCNAME(newRecord, previousRecords) {
continue
}
state1 := copyState(state, serv.Host, state.QType())
state1 := state.NewWithQuestion(serv.Host, state.QType())
nextRecords, err := k.A(zone, state1, append(previousRecords, newRecord))
if err == nil {
@ -87,7 +83,7 @@ func (k Kubernetes) A(zone string, state middleware.State, previousRecords []dns
return records, nil
}
func (k Kubernetes) AAAA(zone string, state middleware.State, previousRecords []dns.RR) (records []dns.RR, err error) {
func (k Kubernetes) AAAA(zone string, state request.Request, previousRecords []dns.RR) (records []dns.RR, err error) {
services, err := k.records(state, false)
if err != nil {
return nil, err
@ -108,11 +104,11 @@ func (k Kubernetes) AAAA(zone string, state middleware.State, previousRecords []
// don't add it, and just continue
continue
}
if isDuplicateCNAME(newRecord, previousRecords) {
if dnsutil.DuplicateCNAME(newRecord, previousRecords) {
continue
}
state1 := copyState(state, serv.Host, state.QType())
state1 := state.NewWithQuestion(serv.Host, state.QType())
nextRecords, err := k.AAAA(zone, state1, append(previousRecords, newRecord))
if err == nil {
@ -149,7 +145,7 @@ func (k Kubernetes) AAAA(zone string, state middleware.State, previousRecords []
// SRV returns SRV records from kubernetes.
// If the Target is not a name but an IP address, a name is created on the fly.
func (k Kubernetes) SRV(zone string, state middleware.State) (records []dns.RR, extra []dns.RR, err error) {
func (k Kubernetes) SRV(zone string, state request.Request) (records []dns.RR, extra []dns.RR, err error) {
services, err := k.records(state, false)
if err != nil {
return nil, nil, err
@ -207,7 +203,7 @@ func (k Kubernetes) SRV(zone string, state middleware.State) (records []dns.RR,
}
// Internal name, we should have some info on them, either v4 or v6
// Clients expect a complete answer, because we are a recursor in their view.
state1 := copyState(state, srv.Target, dns.TypeA)
state1 := state.NewWithQuestion(srv.Target, dns.TypeA)
addr, e1 := k.A(zone, state1, nil)
if e1 == nil {
extra = append(extra, addr...)
@ -231,21 +227,21 @@ func (k Kubernetes) SRV(zone string, state middleware.State) (records []dns.RR,
}
// Returning MX records from kubernetes not implemented.
func (k Kubernetes) MX(zone string, state middleware.State) (records []dns.RR, extra []dns.RR, err error) {
func (k Kubernetes) MX(zone string, state request.Request) (records []dns.RR, extra []dns.RR, err error) {
return nil, nil, err
}
// Returning CNAME records from kubernetes not implemented.
func (k Kubernetes) CNAME(zone string, state middleware.State) (records []dns.RR, err error) {
func (k Kubernetes) CNAME(zone string, state request.Request) (records []dns.RR, err error) {
return nil, err
}
// Returning TXT records from kubernetes not implemented.
func (k Kubernetes) TXT(zone string, state middleware.State) (records []dns.RR, err error) {
func (k Kubernetes) TXT(zone string, state request.Request) (records []dns.RR, err error) {
return nil, err
}
func (k Kubernetes) NS(zone string, state middleware.State) (records, extra []dns.RR, err error) {
func (k Kubernetes) NS(zone string, state request.Request) (records, extra []dns.RR, err error) {
// NS record for this zone live in a special place, ns.dns.<zone>. Fake our lookup.
// only a tad bit fishy...
old := state.QName()
@ -278,7 +274,7 @@ func (k Kubernetes) NS(zone string, state middleware.State) (records, extra []dn
}
// SOA Record returns a SOA record.
func (k Kubernetes) SOA(zone string, state middleware.State) *dns.SOA {
func (k Kubernetes) SOA(zone string, state request.Request) *dns.SOA {
header := dns.RR_Header{Name: zone, Rrtype: dns.TypeSOA, Ttl: 300, Class: dns.ClassINET}
return &dns.SOA{Hdr: header,
Mbox: "hostmaster." + zone,
@ -291,9 +287,9 @@ func (k Kubernetes) SOA(zone string, state middleware.State) *dns.SOA {
}
}
func (k Kubernetes) PTR(zone string, state middleware.State) ([]dns.RR, error) {
reverseIP, ok := extractIP(state.Name())
if !ok {
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())
}
@ -318,41 +314,3 @@ func (k Kubernetes) PTR(zone string, state middleware.State) ([]dns.RR, error) {
}
return records, nil
}
func isDuplicateCNAME(r *dns.CNAME, records []dns.RR) bool {
for _, rec := range records {
if v, ok := rec.(*dns.CNAME); ok {
if v.Target == r.Target {
return true
}
}
}
return false
}
func copyState(state middleware.State, target string, typ uint16) middleware.State {
state1 := middleware.State{W: state.W, Req: state.Req.Copy()}
state1.Req.Question[0] = dns.Question{Name: dns.Fqdn(target), Qtype: dns.ClassINET, Qclass: typ}
return state1
}
// extractIP turns a standard PTR reverse record lookup name
// into an IP address
func extractIP(reverseName string) (string, bool) {
if !strings.HasSuffix(reverseName, arpaSuffix) {
return "", false
}
search := strings.TrimSuffix(reverseName, arpaSuffix)
// reverse the segments and then combine them
segments := reverseArray(strings.Split(search, "."))
return strings.Join(segments, "."), true
}
func reverseArray(arr []string) []string {
for i := 0; i < len(arr)/2; i++ {
j := len(arr) - i - 1
arr[i], arr[j] = arr[j], arr[i]
}
return arr
}