Make CoreDNS a server type plugin for Caddy (#220)

* Make CoreDNS a server type plugin for Caddy

Remove code we don't need and port all middleware over. Fix all tests
and rework the documentation.

Also make `go generate` build a caddy binary which we then copy into
our directory. This means `go build`-builds remain working as-is.

And new etc instances in each etcd test for better isolation.
Fix more tests and rework test.Server with the newer support Caddy offers.

Fix Makefile to support new mode of operation.
This commit is contained in:
Miek Gieben 2016-08-19 17:14:17 -07:00 committed by GitHub
parent a1989c3523
commit 9ac3cab1b7
140 changed files with 2058 additions and 8229 deletions

View file

@ -16,10 +16,10 @@ import (
"github.com/miekg/dns"
"k8s.io/kubernetes/pkg/api"
unversionedapi "k8s.io/kubernetes/pkg/api/unversioned"
"k8s.io/kubernetes/pkg/labels"
unversionedclient "k8s.io/kubernetes/pkg/client/unversioned"
"k8s.io/kubernetes/pkg/client/unversioned/clientcmd"
clientcmdapi "k8s.io/kubernetes/pkg/client/unversioned/clientcmd/api"
"k8s.io/kubernetes/pkg/labels"
)
type Kubernetes struct {
@ -32,10 +32,10 @@ type Kubernetes struct {
NameTemplate *nametemplate.NameTemplate
Namespaces []string
LabelSelector *unversionedapi.LabelSelector
Selector *labels.Selector
Selector *labels.Selector
}
func (g *Kubernetes) StartKubeCache() error {
func (g *Kubernetes) InitKubeCache() error {
// For a custom api server or running outside a k8s cluster
// set URL in env.KUBERNETES_MASTER or set endpoint in Corefile
loadingRules := clientcmd.NewDefaultClientConfigLoadingRules()
@ -46,7 +46,6 @@ func (g *Kubernetes) StartKubeCache() error {
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 := unversionedclient.New(config)
@ -58,20 +57,17 @@ func (g *Kubernetes) StartKubeCache() error {
if g.LabelSelector == nil {
log.Printf("[INFO] Kubernetes middleware configured without a label selector. No label-based filtering will be performed.")
} else {
var selector labels.Selector
var selector labels.Selector
selector, err = unversionedapi.LabelSelectorAsSelector(g.LabelSelector)
g.Selector = &selector
if err != nil {
log.Printf("[ERROR] Unable to create Selector for LabelSelector '%s'.Error was: %s", g.LabelSelector, err)
return err
}
g.Selector = &selector
if err != nil {
log.Printf("[ERROR] Unable to create Selector for LabelSelector '%s'.Error was: %s", g.LabelSelector, err)
return err
}
log.Printf("[INFO] Kubernetes middleware configured with the label selector '%s'. Only kubernetes objects matching this label selector will be exposed.", unversionedapi.FormatLabelSelector(g.LabelSelector))
}
log.Printf("[debug] Starting kubernetes middleware with k8s API resync period: %s", g.ResyncPeriod)
g.APIConn = newdnsController(kubeClient, g.ResyncPeriod, g.Selector)
go g.APIConn.Run()
return err
}
@ -115,7 +111,6 @@ func (g *Kubernetes) Records(name string, exact bool) ([]msg.Service, error) {
typeName string
)
log.Printf("[debug] enter Records('%v', '%v')\n", name, exact)
zone, serviceSegments := g.getZoneForName(name)
// TODO: Implementation above globbed together segments for the serviceName if
@ -137,30 +132,18 @@ func (g *Kubernetes) Records(name string, exact bool) ([]msg.Service, error) {
serviceName = util.WildcardStar
}
log.Printf("[debug] published namespaces: %v\n", g.Namespaces)
log.Printf("[debug] exact: %v\n", exact)
log.Printf("[debug] zone: %v\n", zone)
log.Printf("[debug] servicename: %v\n", serviceName)
log.Printf("[debug] namespace: %v\n", namespace)
log.Printf("[debug] typeName: %v\n", typeName)
log.Printf("[debug] APIconn: %v\n", g.APIConn)
nsWildcard := util.SymbolContainsWildcard(namespace)
serviceWildcard := util.SymbolContainsWildcard(serviceName)
// Abort if the namespace does not contain a wildcard, and namespace is not published per CoreFile
// Case where namespace contains a wildcard is handled in Get(...) method.
if (!nsWildcard) && (len(g.Namespaces) > 0) && (!util.StringInSlice(namespace, g.Namespaces)) {
log.Printf("[debug] Namespace '%v' is not published by Corefile\n", namespace)
return nil, nil
}
log.Printf("before g.Get(namespace, nsWildcard, serviceName, serviceWildcard): %v %v %v %v", namespace, nsWildcard, serviceName, serviceWildcard)
log.Printf("[debug] 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 {
log.Printf("[ERROR] Got error while looking up ServiceItems. Error is: %v\n", err)
return nil, err
}
if k8sItems == nil {
@ -178,7 +161,6 @@ func (g *Kubernetes) getRecordsForServiceItems(serviceItems []api.Service, value
for _, item := range serviceItems {
clusterIP := item.Spec.ClusterIP
log.Printf("[debug] clusterIP: %v\n", clusterIP)
// Create records by constructing record name from template...
//values.Namespace = item.Metadata.Namespace
@ -188,13 +170,11 @@ func (g *Kubernetes) getRecordsForServiceItems(serviceItems []api.Service, value
// 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: int(p.Port)}
records = append(records, s)
}
}
log.Printf("[debug] records from getRecordsForServiceItems(): %v\n", records)
return records
}
@ -202,13 +182,6 @@ func (g *Kubernetes) getRecordsForServiceItems(serviceItems []api.Service, value
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 []api.Service
for _, item := range serviceList.Items {
@ -216,7 +189,6 @@ func (g *Kubernetes) Get(namespace string, nsWildcard bool, servicename string,
// 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.Namespace, g.Namespaces)) {
log.Printf("[debug] Namespace '%v' is not published by Corefile\n", item.Namespace)
continue
}
resultItems = append(resultItems, item)