Switch over to k8s notification API (#202)
* Merge notification code by @aledbf and update for recent changes. * Fix travis environment to correctly build with k8s.io and forked repositories. * Refactored kubernetes Corefile parser * Added lots of Corefile parsing tests
This commit is contained in:
Michael Richmond
GitHub
parent
604d2a3730
commit
6d90b745e0
13 changed files with 609 additions and 237 deletions
|
|
@ -4,33 +4,70 @@ package kubernetes
|
|||
import (
|
||||
"errors"
|
||||
"log"
|
||||
"strings"
|
||||
"time"
|
||||
|
||||
"github.com/miekg/coredns/middleware"
|
||||
k8sc "github.com/miekg/coredns/middleware/kubernetes/k8sclient"
|
||||
"github.com/miekg/coredns/middleware/kubernetes/msg"
|
||||
"github.com/miekg/coredns/middleware/kubernetes/nametemplate"
|
||||
"github.com/miekg/coredns/middleware/kubernetes/util"
|
||||
"github.com/miekg/coredns/middleware/proxy"
|
||||
|
||||
"github.com/miekg/dns"
|
||||
"k8s.io/kubernetes/pkg/api"
|
||||
"k8s.io/kubernetes/pkg/client/unversioned"
|
||||
"k8s.io/kubernetes/pkg/client/unversioned/clientcmd"
|
||||
clientcmdapi "k8s.io/kubernetes/pkg/client/unversioned/clientcmd/api"
|
||||
)
|
||||
|
||||
const (
|
||||
defaultResyncPeriod = 5 * time.Minute
|
||||
)
|
||||
|
||||
type Kubernetes struct {
|
||||
Next middleware.Handler
|
||||
Zones []string
|
||||
Proxy proxy.Proxy // Proxy for looking up names during the resolution process
|
||||
APIConn *k8sc.K8sConnector
|
||||
APIEndpoint string
|
||||
APIConn *dnsController
|
||||
ResyncPeriod time.Duration
|
||||
NameTemplate *nametemplate.NameTemplate
|
||||
Namespaces []string
|
||||
}
|
||||
|
||||
func (g *Kubernetes) StartKubeCache() error {
|
||||
// For a custom api server or running outside a k8s cluster
|
||||
// set URL in env.KUBERNETES_MASTER
|
||||
loadingRules := clientcmd.NewDefaultClientConfigLoadingRules()
|
||||
overrides := &clientcmd.ConfigOverrides{}
|
||||
if len(g.APIEndpoint) > 0 {
|
||||
overrides.ClusterInfo = clientcmdapi.Cluster{Server: g.APIEndpoint}
|
||||
}
|
||||
clientConfig := clientcmd.NewNonInteractiveDeferredLoadingClientConfig(loadingRules, overrides)
|
||||
config, err := clientConfig.ClientConfig()
|
||||
if err != nil {
|
||||
log.Printf("[debug] error connecting to the client: %v", err)
|
||||
return err
|
||||
}
|
||||
kubeClient, err := unversioned.New(config)
|
||||
|
||||
if err != nil {
|
||||
log.Printf("[ERROR] Failed to create kubernetes notification controller: %v", err)
|
||||
return err
|
||||
}
|
||||
g.APIConn = newdnsController(kubeClient, g.ResyncPeriod)
|
||||
|
||||
go g.APIConn.Run()
|
||||
|
||||
return err
|
||||
}
|
||||
|
||||
// getZoneForName returns the zone string that matches the name and a
|
||||
// list of the DNS labels from name that are within the zone.
|
||||
// For example, if "coredns.local" is a zone configured for the
|
||||
// Kubernetes middleware, then getZoneForName("a.b.coredns.local")
|
||||
// will return ("coredns.local", ["a", "b"]).
|
||||
func (g Kubernetes) getZoneForName(name string) (string, []string) {
|
||||
func (g *Kubernetes) getZoneForName(name string) (string, []string) {
|
||||
var zone string
|
||||
var serviceSegments []string
|
||||
|
||||
|
|
@ -51,7 +88,14 @@ func (g Kubernetes) getZoneForName(name string) (string, []string) {
|
|||
// If exact is true, it will lookup just
|
||||
// this name. This is used when find matches when completing SRV lookups
|
||||
// for instance.
|
||||
func (g Kubernetes) Records(name string, exact bool) ([]msg.Service, error) {
|
||||
func (g *Kubernetes) Records(name string, exact bool) ([]msg.Service, error) {
|
||||
// TODO: refector this.
|
||||
// Right now GetNamespaceFromSegmentArray do not supports PRE queries
|
||||
if strings.HasSuffix(name, arpaSuffix) {
|
||||
ip, _ := extractIP(name)
|
||||
records := g.getServiceRecordForIP(ip, name)
|
||||
return records, nil
|
||||
}
|
||||
var (
|
||||
serviceName string
|
||||
namespace string
|
||||
|
|
@ -99,6 +143,7 @@ func (g Kubernetes) Records(name string, exact bool) ([]msg.Service, error) {
|
|||
return nil, nil
|
||||
}
|
||||
|
||||
log.Printf("before g.Get(namespace, nsWildcard, serviceName, serviceWildcard): %v %v %v %v", namespace, nsWildcard, serviceName, serviceWildcard)
|
||||
k8sItems, err := g.Get(namespace, nsWildcard, serviceName, serviceWildcard)
|
||||
log.Printf("[debug] k8s items: %v\n", k8sItems)
|
||||
if err != nil {
|
||||
|
|
@ -115,7 +160,7 @@ func (g Kubernetes) Records(name string, exact bool) ([]msg.Service, error) {
|
|||
}
|
||||
|
||||
// TODO: assemble name from parts found in k8s data based on name template rather than reusing query string
|
||||
func (g Kubernetes) getRecordsForServiceItems(serviceItems []k8sc.ServiceItem, values nametemplate.NameValues) []msg.Service {
|
||||
func (g *Kubernetes) getRecordsForServiceItems(serviceItems []api.Service, values nametemplate.NameValues) []msg.Service {
|
||||
var records []msg.Service
|
||||
|
||||
for _, item := range serviceItems {
|
||||
|
|
@ -131,7 +176,7 @@ func (g Kubernetes) getRecordsForServiceItems(serviceItems []k8sc.ServiceItem, v
|
|||
// Create records for each exposed port...
|
||||
for _, p := range item.Spec.Ports {
|
||||
log.Printf("[debug] port: %v\n", p.Port)
|
||||
s := msg.Service{Host: clusterIP, Port: p.Port}
|
||||
s := msg.Service{Host: clusterIP, Port: int(p.Port)}
|
||||
records = append(records, s)
|
||||
}
|
||||
}
|
||||
|
|
@ -141,22 +186,24 @@ func (g Kubernetes) getRecordsForServiceItems(serviceItems []k8sc.ServiceItem, v
|
|||
}
|
||||
|
||||
// Get performs the call to the Kubernetes http API.
|
||||
func (g Kubernetes) Get(namespace string, nsWildcard bool, servicename string, serviceWildcard bool) ([]k8sc.ServiceItem, error) {
|
||||
serviceList, err := g.APIConn.GetServiceList()
|
||||
func (g *Kubernetes) Get(namespace string, nsWildcard bool, servicename string, serviceWildcard bool) ([]api.Service, error) {
|
||||
serviceList := g.APIConn.GetServiceList()
|
||||
|
||||
/* TODO: Remove?
|
||||
if err != nil {
|
||||
log.Printf("[ERROR] Getting service list produced error: %v", err)
|
||||
return nil, err
|
||||
}
|
||||
*/
|
||||
|
||||
var resultItems []k8sc.ServiceItem
|
||||
var resultItems []api.Service
|
||||
|
||||
for _, item := range serviceList.Items {
|
||||
if symbolMatches(namespace, item.Metadata.Namespace, nsWildcard) && symbolMatches(servicename, item.Metadata.Name, serviceWildcard) {
|
||||
if symbolMatches(namespace, item.Namespace, nsWildcard) && symbolMatches(servicename, item.Name, serviceWildcard) {
|
||||
// If namespace has a wildcard, filter results against Corefile namespace list.
|
||||
// (Namespaces without a wildcard were filtered before the call to this function.)
|
||||
if nsWildcard && (len(g.Namespaces) > 0) && (!util.StringInSlice(item.Metadata.Namespace, g.Namespaces)) {
|
||||
log.Printf("[debug] Namespace '%v' is not published by Corefile\n", item.Metadata.Namespace)
|
||||
if nsWildcard && (len(g.Namespaces) > 0) && (!util.StringInSlice(item.Namespace, g.Namespaces)) {
|
||||
log.Printf("[debug] Namespace '%v' is not published by Corefile\n", item.Namespace)
|
||||
continue
|
||||
}
|
||||
resultItems = append(resultItems, item)
|
||||
|
|
@ -179,104 +226,26 @@ func symbolMatches(queryString string, candidateString string, wildcard bool) bo
|
|||
return result
|
||||
}
|
||||
|
||||
// TODO: Remove these unused functions. One is related to Ttl calculation
|
||||
// Implement Ttl and priority calculation based on service count before
|
||||
// removing this code.
|
||||
/*
|
||||
// splitDNSName separates the name into DNS segments and reverses the segments.
|
||||
func (g Kubernetes) splitDNSName(name string) []string {
|
||||
l := dns.SplitDomainName(name)
|
||||
|
||||
for i, j := 0, len(l)-1; i < j; i, j = i+1, j-1 {
|
||||
l[i], l[j] = l[j], l[i]
|
||||
}
|
||||
|
||||
return l
|
||||
}
|
||||
*/
|
||||
// skydns/local/skydns/east/staging/web
|
||||
// skydns/local/skydns/west/production/web
|
||||
//
|
||||
// skydns/local/skydns/*/*/web
|
||||
// skydns/local/skydns/*/web
|
||||
/*
|
||||
// loopNodes recursively loops through the nodes and returns all the values. The nodes' keyname
|
||||
// will be match against any wildcards when star is true.
|
||||
func (g Kubernetes) loopNodes(ns []*etcdc.Node, nameParts []string, star bool, bx map[msg.Service]bool) (sx []msg.Service, err error) {
|
||||
if bx == nil {
|
||||
bx = make(map[msg.Service]bool)
|
||||
}
|
||||
Nodes:
|
||||
for _, n := range ns {
|
||||
if n.Dir {
|
||||
nodes, err := g.loopNodes(n.Nodes, nameParts, star, bx)
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
sx = append(sx, nodes...)
|
||||
continue
|
||||
}
|
||||
if star {
|
||||
keyParts := strings.Split(n.Key, "/")
|
||||
for i, n := range nameParts {
|
||||
if i > len(keyParts)-1 {
|
||||
// name is longer than key
|
||||
continue Nodes
|
||||
}
|
||||
if n == "*" || n == "any" {
|
||||
continue
|
||||
}
|
||||
if keyParts[i] != n {
|
||||
continue Nodes
|
||||
}
|
||||
}
|
||||
}
|
||||
serv := new(msg.Service)
|
||||
if err := json.Unmarshal([]byte(n.Value), serv); err != nil {
|
||||
return nil, err
|
||||
}
|
||||
b := msg.Service{Host: serv.Host, Port: serv.Port, Priority: serv.Priority, Weight: serv.Weight, Text: serv.Text, Key: n.Key}
|
||||
if _, ok := bx[b]; ok {
|
||||
continue
|
||||
}
|
||||
bx[b] = true
|
||||
|
||||
serv.Key = n.Key
|
||||
serv.Ttl = g.Ttl(n, serv)
|
||||
if serv.Priority == 0 {
|
||||
serv.Priority = priority
|
||||
}
|
||||
sx = append(sx, *serv)
|
||||
}
|
||||
return sx, nil
|
||||
}
|
||||
|
||||
// Ttl returns the smaller of the kubernetes TTL and the service's
|
||||
// TTL. If neither of these are set (have a zero value), a default is used.
|
||||
func (g Kubernetes) Ttl(node *etcdc.Node, serv *msg.Service) uint32 {
|
||||
kubernetesTtl := uint32(node.TTL)
|
||||
|
||||
if kubernetesTtl == 0 && serv.Ttl == 0 {
|
||||
return ttl
|
||||
}
|
||||
if kubernetesTtl == 0 {
|
||||
return serv.Ttl
|
||||
}
|
||||
if serv.Ttl == 0 {
|
||||
return kubernetesTtl
|
||||
}
|
||||
if kubernetesTtl < serv.Ttl {
|
||||
return kubernetesTtl
|
||||
}
|
||||
return serv.Ttl
|
||||
}
|
||||
*/
|
||||
|
||||
// kubernetesNameError checks if the error is ErrorCodeKeyNotFound from kubernetes.
|
||||
func isKubernetesNameError(err error) bool {
|
||||
return false
|
||||
}
|
||||
|
||||
func (g *Kubernetes) getServiceRecordForIP(ip, name string) []msg.Service {
|
||||
svcList, err := g.APIConn.svcLister.List()
|
||||
if err != nil {
|
||||
return nil
|
||||
}
|
||||
|
||||
for _, service := range svcList.Items {
|
||||
if service.Spec.ClusterIP == ip {
|
||||
return []msg.Service{msg.Service{Host: ip}}
|
||||
}
|
||||
}
|
||||
|
||||
return nil
|
||||
}
|
||||
|
||||
const (
|
||||
priority = 10 // default priority when nothing is set
|
||||
ttl = 300 // default ttl when nothing is set
|
||||
|
|
|
|||
Loading…
Add table
Add a link
Reference in a new issue