Add -dns to docker daemon

builder.go

@@ -7,6 +7,8 @@ import (
 	"time"
 )
 
+var defaultDns = []string{"8.8.8.8", "8.8.4.4"}
+
 type Builder struct {
 	runtime      *Runtime
 	repositories *TagStore
@@ -67,14 +69,20 @@ func (builder *Builder) Create(config *Config) (*Container, error) {
 	}
 
 	// If custom dns exists, then create a resolv.conf for the container
+	if len(config.Dns) > 0 || len(builder.runtime.Dns) > 0 {
+		var dns []string
 		if len(config.Dns) > 0 {
+			dns = config.Dns
+		} else {
+			dns = builder.runtime.Dns
+		}
 		container.ResolvConfPath = path.Join(container.root, "resolv.conf")
 		f, err := os.Create(container.ResolvConfPath)
 		if err != nil {
 			return nil, err
 		}
 		defer f.Close()
-		for _, dns := range config.Dns {
+		for _, dns := range dns {
 			if _, err := f.Write([]byte("nameserver " + dns + "\n")); err != nil {
 				return nil, err
 			}

docker/docker.go

@@ -33,6 +33,11 @@ func main() {
 	bridgeName := flag.String("b", "", "Attach containers to a pre-existing network bridge")
 	pidfile := flag.String("p", "/var/run/docker.pid", "File containing process PID")
 	flHost := flag.String("H", fmt.Sprintf("%s:%d", host, port), "Host:port to bind/connect to")
+
+	flags := flag.NewFlagSet("docker", flag.ContinueOnError)
+	var flDns docker.ListOpts
+	flags.Var(&flDns, "dns", "Set custom dns servers")
+
 	flag.Parse()
 	if *bridgeName != "" {
 		docker.NetworkBridgeIface = *bridgeName
@@ -65,7 +70,7 @@ func main() {
 			flag.Usage()
 			return
 		}
-		if err := daemon(*pidfile, host, port, *flAutoRestart); err != nil {
+		if err := daemon(*pidfile, host, port, *flAutoRestart, flDns); err != nil {
 			log.Fatal(err)
 			os.Exit(-1)
 		}
@@ -104,7 +109,7 @@ func removePidFile(pidfile string) {
 	}
 }
 
-func daemon(pidfile, addr string, port int, autoRestart bool) error {
+func daemon(pidfile, addr string, port int, autoRestart bool, flDns docker.ListOpts) error {
 	if addr != "127.0.0.1" {
 		log.Println("/!\\ DON'T BIND ON ANOTHER IP ADDRESS THAN 127.0.0.1 IF YOU DON'T KNOW WHAT YOU'RE DOING /!\\")
 	}
@@ -122,7 +127,7 @@ func daemon(pidfile, addr string, port int, autoRestart bool) error {
 		os.Exit(0)
 	}()
 
-	server, err := docker.NewServer(autoRestart)
+	server, err := docker.NewServer(autoRestart, flDns)
 	if err != nil {
 		return err
 	}

runtime.go

@@ -32,6 +32,7 @@ type Runtime struct {
 	autoRestart    bool
 	volumes        *Graph
 	srv            *Server
+	Dns            []string
 }
 
 var sysInitPath string
@@ -245,11 +246,12 @@ func (runtime *Runtime) UpdateCapabilities(quiet bool) {
 }
 
 // FIXME: harmonize with NewGraph()
-func NewRuntime(autoRestart bool) (*Runtime, error) {
+func NewRuntime(autoRestart bool, dns []string) (*Runtime, error) {
 	runtime, err := NewRuntimeFromDirectory("/var/lib/docker", autoRestart)
 	if err != nil {
 		return nil, err
 	}
+	runtime.Dns = dns
 
 	if k, err := utils.GetKernelVersion(); err != nil {
 		log.Printf("WARNING: %s\n", err)

server.go

@@ -869,11 +869,11 @@ func (srv *Server) ImageInspect(name string) (*Image, error) {
 	return nil, fmt.Errorf("No such image: %s", name)
 }
 
-func NewServer(autoRestart bool) (*Server, error) {
+func NewServer(autoRestart bool, dns ListOpts) (*Server, error) {
 	if runtime.GOARCH != "amd64" {
 		log.Fatalf("The docker runtime currently only supports amd64 (not %s). This will change in the future. Aborting.", runtime.GOARCH)
 	}
-	runtime, err := NewRuntime(autoRestart)
+	runtime, err := NewRuntime(autoRestart, dns)
 	if err != nil {
 		return nil, err
 	}

utils/utils.go

@@ -585,7 +585,7 @@ func (sf *StreamFormatter) FormatStatus(format string, a ...interface{}) []byte
 	sf.used = true
 	str := fmt.Sprintf(format, a...)
 	if sf.json {
-		b, err := json.Marshal(&JSONMessage{Status:str});
+		b, err := json.Marshal(&JSONMessage{Status: str})
 		if err != nil {
 			return sf.FormatError(err)
 		}