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, 25 insertions, 31 deletions

diff --git a/middleware/kubernetes/controller.go b/middleware/kubernetes/controller.go
index 3fbea313e..5de16d61c 100644
--- a/middleware/kubernetes/controller.go
+++ b/middleware/kubernetes/controller.go
@@ -2,7 +2,6 @@ package kubernetes
 
 import (
 	"fmt"
-	"log"
 	"sync"
 	"time"
 
@@ -12,7 +11,7 @@ import (
 	"k8s.io/kubernetes/pkg/client/cache"
 	client "k8s.io/kubernetes/pkg/client/unversioned"
 	"k8s.io/kubernetes/pkg/controller/framework"
-    "k8s.io/kubernetes/pkg/labels"
+	"k8s.io/kubernetes/pkg/labels"
 	"k8s.io/kubernetes/pkg/runtime"
 	"k8s.io/kubernetes/pkg/watch"
 )
@@ -24,7 +23,7 @@ var (
 type dnsController struct {
 	client *client.Client
 
-    selector *labels.Selector
+	selector *labels.Selector
 
 	endpController *framework.Controller
 	svcController  *framework.Controller
@@ -45,9 +44,9 @@ type dnsController struct {
 // newDNSController creates a controller for coredns
 func newdnsController(kubeClient *client.Client, resyncPeriod time.Duration, lselector *labels.Selector) *dnsController {
 	dns := dnsController{
-		client: kubeClient,
-        selector: lselector,
-		stopCh: make(chan struct{}),
+		client:   kubeClient,
+		selector: lselector,
+		stopCh:   make(chan struct{}),
 	}
 
 	dns.endpLister.Store, dns.endpController = framework.NewInformer(
@@ -76,54 +75,54 @@ func newdnsController(kubeClient *client.Client, resyncPeriod time.Duration, lse
 
 func serviceListFunc(c *client.Client, ns string, s *labels.Selector) func(api.ListOptions) (runtime.Object, error) {
 	return func(opts api.ListOptions) (runtime.Object, error) {
-        if s != nil {
-            opts.LabelSelector = *s
-        }
+		if s != nil {
+			opts.LabelSelector = *s
+		}
 		return c.Services(ns).List(opts)
 	}
 }
 
 func serviceWatchFunc(c *client.Client, ns string, s *labels.Selector) func(options api.ListOptions) (watch.Interface, error) {
 	return func(options api.ListOptions) (watch.Interface, error) {
-        if s != nil {
-            options.LabelSelector = *s
-        }
+		if s != nil {
+			options.LabelSelector = *s
+		}
 		return c.Services(ns).Watch(options)
 	}
 }
 
 func endpointsListFunc(c *client.Client, ns string, s *labels.Selector) func(api.ListOptions) (runtime.Object, error) {
 	return func(opts api.ListOptions) (runtime.Object, error) {
-        if s != nil {
-            opts.LabelSelector = *s
-        }
+		if s != nil {
+			opts.LabelSelector = *s
+		}
 		return c.Endpoints(ns).List(opts)
 	}
 }
 
 func endpointsWatchFunc(c *client.Client, ns string, s *labels.Selector) func(options api.ListOptions) (watch.Interface, error) {
 	return func(options api.ListOptions) (watch.Interface, error) {
-        if s != nil {
-            options.LabelSelector = *s
-        }
+		if s != nil {
+			options.LabelSelector = *s
+		}
 		return c.Endpoints(ns).Watch(options)
 	}
 }
 
 func namespaceListFunc(c *client.Client, s *labels.Selector) func(api.ListOptions) (runtime.Object, error) {
 	return func(opts api.ListOptions) (runtime.Object, error) {
-        if s != nil {
-            opts.LabelSelector = *s
-        }
+		if s != nil {
+			opts.LabelSelector = *s
+		}
 		return c.Namespaces().List(opts)
 	}
 }
 
 func namespaceWatchFunc(c *client.Client, s *labels.Selector) func(options api.ListOptions) (watch.Interface, error) {
 	return func(options api.ListOptions) (watch.Interface, error) {
-        if s != nil {
-            options.LabelSelector = *s
-        }
+		if s != nil {
+			options.LabelSelector = *s
+		}
 		return c.Namespaces().Watch(options)
 	}
 }
@@ -140,7 +139,6 @@ func (dns *dnsController) Stop() error {
 	// Only try draining the workqueue if we haven't already.
 	if !dns.shutdown {
 		close(dns.stopCh)
-		log.Println("shutting down controller queues")
 		dns.shutdown = true
 
 		return nil
@@ -151,14 +149,10 @@ func (dns *dnsController) Stop() error {
 
 // Run starts the controller.
 func (dns *dnsController) Run() {
-	log.Println("[debug] Starting k8s notification controllers")
-
 	go dns.endpController.Run(dns.stopCh)
 	go dns.svcController.Run(dns.stopCh)
 	go dns.nsController.Run(dns.stopCh)
-
 	<-dns.stopCh
-	log.Println("[debug] shutting down coredns controller")
 }
 
 func (dns *dnsController) GetNamespaceList() *api.NamespaceList {
@@ -203,12 +197,12 @@ func (dns *dnsController) GetServiceInNamespace(namespace string, servicename st
 	svcObj, svcExists, err := dns.svcLister.Store.GetByKey(svcKey)
 
 	if err != nil {
-		log.Printf("error getting service %v from the cache: %v\n", svcKey, err)
+		// TODO(...): should return err here
 		return nil
 	}
 
 	if !svcExists {
-		log.Printf("service %v does not exists\n", svcKey)
+		// TODO(...): should return err here
 		return nil
 	}