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.

1 files changed, 10 insertions, 38 deletions

diff --git a/middleware/kubernetes/kubernetes.go b/middleware/kubernetes/kubernetes.go
index 5e2a1bf53..59a044140 100644
--- a/middleware/kubernetes/kubernetes.go
+++ b/middleware/kubernetes/kubernetes.go
@@ -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)