openshift start network should pass stopCh down to DNS

Allow graceful shutdown of the DNS server so that we can remove
ourselves from dnsmasq.

Author: smarterclayton

pkg/cmd/server/kubernetes/network/network.go

@@ -48,10 +48,10 @@ func (c *NetworkConfig) RunSDN() {
 }
 
 // RunDNS starts the DNS server as soon as services are loaded.
-func (c *NetworkConfig) RunDNS() {
+func (c *NetworkConfig) RunDNS(stopCh <-chan struct{}) {
 	go func() {
 		glog.Infof("Starting DNS on %s", c.DNSServer.Config.DnsAddr)
-		err := c.DNSServer.ListenAndServe()
+		err := c.DNSServer.ListenAndServe(stopCh)
 		glog.Fatalf("DNS server failed to start: %v", err)
 	}()
 }

pkg/cmd/server/origin/dns_server.go

@@ -6,6 +6,8 @@ import (
 
 	"github.com/golang/glog"
 
+	"k8s.io/apimachinery/pkg/util/wait"
+
 	cmdutil "github.com/openshift/origin/pkg/cmd/util"
 	"github.com/openshift/origin/pkg/dns"
 )
@@ -52,7 +54,7 @@ func (c *MasterConfig) RunDNSServer() {
 
 	go func() {
 		s := dns.NewServer(config, services, endpoints, "apiserver")
-		err := s.ListenAndServe()
+		err := s.ListenAndServe(wait.NeverStop)
 		glog.Fatalf("Could not start DNS: %v", err)
 	}()
 

pkg/cmd/server/start/start_allinone.go

@@ -16,6 +16,7 @@ import (
 	"github.com/spf13/cobra"
 
 	kerrors "k8s.io/apimachinery/pkg/api/errors"
+	"k8s.io/apimachinery/pkg/util/wait"
 	"k8s.io/apiserver/pkg/util/flag"
 	"k8s.io/kubernetes/pkg/kubectl/cmd/templates"
 	kcmdutil "k8s.io/kubernetes/pkg/kubectl/cmd/util"
@@ -26,7 +27,6 @@ import (
 	configapi "github.com/openshift/origin/pkg/cmd/server/apis/config"
 	"github.com/openshift/origin/pkg/cmd/server/origin"
 	tsbcmd "github.com/openshift/origin/pkg/templateservicebroker/cmd/server"
-	"k8s.io/apimachinery/pkg/util/wait"
 )
 
 type AllInOneOptions struct {
@@ -310,7 +310,7 @@ func (o AllInOneOptions) StartAllInOne() error {
 		ConfigFile: o.NodeConfigFile,
 		Output:     o.MasterOptions.Output,
 	}
-	if err := nodeOptions.RunNode(); err != nil {
+	if err := nodeOptions.RunNode(wait.NeverStop); err != nil {
 		return err
 	}
 

pkg/cmd/server/start/start_node.go

@@ -9,6 +9,7 @@ import (
 	"path/filepath"
 	"strings"
 	"syscall"
+	"time"
 
 	"github.com/coreos/go-systemd/daemon"
 	"github.com/golang/glog"
@@ -18,11 +19,11 @@ import (
 	kerrors "k8s.io/apimachinery/pkg/api/errors"
 	utilruntime "k8s.io/apimachinery/pkg/util/runtime"
 	"k8s.io/apimachinery/pkg/util/sets"
-	"k8s.io/apimachinery/pkg/util/wait"
 	kubeletapp "k8s.io/kubernetes/cmd/kubelet/app"
 	"k8s.io/kubernetes/pkg/kubectl/cmd/templates"
 	kcmdutil "k8s.io/kubernetes/pkg/kubectl/cmd/util"
 	"k8s.io/kubernetes/pkg/master/ports"
+	"k8s.io/kubernetes/pkg/util/interrupt"
 
 	"github.com/openshift/library-go/pkg/crypto"
 	"github.com/openshift/origin/pkg/cmd/server/admin"
@@ -115,14 +116,26 @@ var networkLong = templates.LongDesc(`
 
 // NewCommandStartNetwork provides a CLI handler for 'start network' command
 func NewCommandStartNetwork(basename string, out, errout io.Writer) (*cobra.Command, *NodeOptions) {
-	options := &NodeOptions{Output: out}
+	options := &NodeOptions{
+		ExpireDays: crypto.DefaultCertificateLifetimeInDays,
+		Output:     out,
+	}
 
 	cmd := &cobra.Command{
 		Use:   "network",
 		Short: "Launch node network",
 		Long:  fmt.Sprintf(networkLong, basename),
 		Run: func(c *cobra.Command, args []string) {
-			options.Run(c, errout, args, wait.NeverStop)
+			ch := make(chan struct{})
+			interrupt.New(func(s os.Signal) {
+				close(ch)
+				fmt.Fprintf(errout, "interrupt: Gracefully shutting down ...\n")
+				time.Sleep(200 * time.Millisecond)
+				os.Exit(1)
+			}).Run(func() error {
+				options.Run(c, errout, args, ch)
+				return nil
+			})
 		},
 	}
 
@@ -209,7 +222,7 @@ func (o NodeOptions) Complete(cmd *cobra.Command) error {
 
 // StartNode calls RunNode and then waits forever
 func (o NodeOptions) StartNode(stopCh <-chan struct{}) error {
-	if err := o.RunNode(); err != nil {
+	if err := o.RunNode(stopCh); err != nil {
 		return err
 	}
 
@@ -227,7 +240,7 @@ func (o NodeOptions) StartNode(stopCh <-chan struct{}) error {
 // 2.  Reads fully specified node config OR builds a fully specified node config from the args
 // 3.  Writes the fully specified node config and exits if needed
 // 4.  Starts the node based on the fully specified config
-func (o NodeOptions) RunNode() error {
+func (o NodeOptions) RunNode(stopCh <-chan struct{}) error {
 	nodeConfig, configFile, err := o.resolveNodeConfig()
 	if err != nil {
 		return err
@@ -277,7 +290,7 @@ func (o NodeOptions) RunNode() error {
 		return originnode.WriteKubeletFlags(*nodeConfig)
 	}
 
-	return StartNode(*nodeConfig, o.NodeArgs.Components)
+	return StartNode(*nodeConfig, o.NodeArgs.Components, stopCh)
 }
 
 // resolveNodeConfig creates a new configuration on disk by reading from the master, reads
@@ -421,7 +434,7 @@ func execKubelet(kubeletArgs []string) error {
 }
 
 // StartNode launches the node processes.
-func StartNode(nodeConfig configapi.NodeConfig, components *utilflags.ComponentFlag) error {
+func StartNode(nodeConfig configapi.NodeConfig, components *utilflags.ComponentFlag, stopCh <-chan struct{}) error {
 	kubeletArgs, err := nodeoptions.ComputeKubeletFlags(nodeConfig.KubeletArguments, nodeConfig)
 	if err != nil {
 		return fmt.Errorf("cannot create kubelet args: %v", err)
@@ -476,12 +489,12 @@ func StartNode(nodeConfig configapi.NodeConfig, components *utilflags.ComponentF
 		networkConfig.RunProxy()
 	}
 	if components.Enabled(ComponentDNS) && networkConfig.DNSServer != nil {
-		networkConfig.RunDNS()
+		networkConfig.RunDNS(stopCh)
 	}
 
-	networkConfig.InternalKubeInformers.Start(wait.NeverStop)
+	networkConfig.InternalKubeInformers.Start(stopCh)
 	if networkConfig.InternalNetworkInformers != nil {
-		networkConfig.InternalNetworkInformers.Start(wait.NeverStop)
+		networkConfig.InternalNetworkInformers.Start(stopCh)
 	}
 
 	return nil