coredns: default Corefile (#265)

When no Corefile is given, default to loading the whoami middleware on
the default port (2053).  Also add back the -port flag that allows you
to override the default port.

Further cleanup the startup messages and use caddy's OnStartupComplete()
to blurp out which zones and ports we have.  These can be suppressed
with the -quiet flag.

Normal startup:

miek.nl.:1053
miek.nl2.:1053
example.org.:1054
2016/09/17 20:41:19 [INFO] CoreDNS-001 starting
CoreDNS-001 starting

with the -quiet flag:

2016/09/17 20:41:34 [INFO] CoreDNS-001 starting

4 files changed, 44 insertions, 43 deletions

diff --git a/core/coredns.go b/core/coredns.go
index 369230492..eb6e204d6 100644
--- a/core/coredns.go
+++ b/core/coredns.go
@@ -23,6 +23,3 @@ import (
 	_ "github.com/miekg/coredns/middleware/secondary"
 	_ "github.com/miekg/coredns/middleware/whoami"
 )
-
-// Quiet mode will not show any informative output on initialization.
-var Quiet bool
diff --git a/core/dnsserver/register.go b/core/dnsserver/register.go
index c470c9c6d..047fb673f 100644
--- a/core/dnsserver/register.go
+++ b/core/dnsserver/register.go
@@ -1,6 +1,7 @@
 package dnsserver
 
 import (
+	"flag"
 	"fmt"
 	"net"
 	"time"
@@ -12,19 +13,15 @@ import (
 const serverType = "dns"
 
 func init() {
+	flag.StringVar(&Port, "port", DefaultPort, "Default port")
+	flag.BoolVar(&Quiet, "quiet", false, "Quiet mode (no initialization output)")
+
 	caddy.RegisterServerType(serverType, caddy.ServerType{
 		Directives: func() []string { return directives },
 		DefaultInput: func() caddy.Input {
-			if Port == DefaultPort && Zone != "" {
-				return caddy.CaddyfileInput{
-					Filepath:       "Corefile",
-					Contents:       nil,
-					ServerTypeName: serverType,
-				}
-			}
 			return caddy.CaddyfileInput{
 				Filepath:       "Corefile",
-				Contents:       nil,
+				Contents:       []byte(".:" + Port + " {\nwhoami\n}\n"),
 				ServerTypeName: serverType,
 			}
 		},
@@ -63,7 +60,6 @@ func (h *dnsContext) InspectServerBlocks(sourceFile string, serverBlocks []caddy
 			s.Keys[i] = za.String()
 			if v, ok := dups[za.Zone]; ok {
 				return nil, fmt.Errorf("cannot serve %s - zone already defined for %v", za, v)
-
 			}
 			dups[za.Zone] = za.String()
 
@@ -71,7 +67,6 @@ func (h *dnsContext) InspectServerBlocks(sourceFile string, serverBlocks []caddy
 			cfg := &Config{
 				Zone: za.Zone,
 				Port: za.Port,
-				// TODO(miek): more?
 			}
 			h.saveConfig(za.String(), cfg)
 		}
@@ -129,8 +124,6 @@ func groupConfigsByListenAddr(configs []*Config) (map[string][]*Config, error) {
 }
 
 const (
-	// DefaultZone is the default zone.
-	DefaultZone = "."
 	// DefaultPort is the default port.
 	DefaultPort = "2053"
 	// DefaultRoot is the default root folder.
@@ -141,14 +134,15 @@ const (
 // command line flags, etc.
 var (
 	// Root is the site root
+	// TODO(miek): double check if this is used and if we want to use it.
 	Root = DefaultRoot
 
-	// Host is the site host
-	Zone = DefaultZone
-
 	// Port is the site port
 	Port = DefaultPort
 
 	// GracefulTimeout is the maximum duration of a graceful shutdown.
 	GracefulTimeout time.Duration
+
+	// Quiet mode will not show any informative output on initialization.
+	Quiet bool
 )
diff --git a/core/dnsserver/server.go b/core/dnsserver/server.go
index 77a28f477..4e02f1c21 100644
--- a/core/dnsserver/server.go
+++ b/core/dnsserver/server.go
@@ -1,6 +1,7 @@
 package dnsserver
 
 import (
+	"fmt"
 	"log"
 	"net"
 	"runtime"
@@ -213,6 +214,18 @@ func (s *Server) ServeDNS(w dns.ResponseWriter, r *dns.Msg) {
 	log.Printf("[INFO] \"%s %s %s\" - No such zone at %s (Remote: %s)", dns.Type(r.Question[0].Qtype), dns.Class(r.Question[0].Qclass), q, s.Addr, remoteHost)
 }
 
+// OnStartupComplete lists the sites served by this server
+// and any relevant information, assuming Quiet == false.
+func (s *Server) OnStartupComplete() {
+	if Quiet {
+		return
+	}
+
+	for zone, config := range s.zones {
+		fmt.Println(zone + ":" + config.Port)
+	}
+}
+
 // DefaultErrorFunc responds to an DNS request with an error.
 func DefaultErrorFunc(w dns.ResponseWriter, r *dns.Msg, rcode int) {
 	state := request.Request{W: w, Req: r}
diff --git a/coremain/run.go b/coremain/run.go
index 94b0076a0..7552074c1 100644
--- a/coremain/run.go
+++ b/coremain/run.go
@@ -13,8 +13,9 @@ import (
 
 	"github.com/mholt/caddy"
 
+	"github.com/miekg/coredns/core/dnsserver"
 	// Plug in CoreDNS
-	"github.com/miekg/coredns/core"
+	_ "github.com/miekg/coredns/core"
 )
 
 func init() {
@@ -28,7 +29,6 @@ func init() {
 	flag.BoolVar(&plugins, "plugins", false, "List installed plugins")
 	flag.StringVar(&logfile, "log", "", "Process log file")
 	flag.StringVar(&caddy.PidFile, "pidfile", "", "Path to write pid file")
-	flag.BoolVar(&core.Quiet, "quiet", false, "Quiet mode (no initialization output)")
 	flag.BoolVar(&version, "version", false, "Show version")
 
 	caddy.RegisterCaddyfileLoader("flag", caddy.LoaderFunc(confLoader))
@@ -80,34 +80,12 @@ func Run() {
 	}
 
 	logVersion()
+	showVersion()
 
 	// Twiddle your thumbs
 	instance.Wait()
 }
 
-// startNotification will log CoreDNS' version to the log.
-func startupNotification() {
-	if core.Quiet {
-		return
-	}
-	logVersion()
-}
-
-func showVersion() {
-	fmt.Printf("%s-%s\n", caddy.AppName, caddy.AppVersion)
-	if devBuild && gitShortStat != "" {
-		fmt.Printf("%s\n%s\n", gitShortStat, gitFilesModified)
-	}
-}
-
-// logVersion logs the version that is starting.
-func logVersion() {
-	log.Printf("[INFO] %s-%s starting\n", caddy.AppName, caddy.AppVersion)
-	if devBuild && gitShortStat != "" {
-		log.Printf("[INFO] %s\n%s\n", gitShortStat, gitFilesModified)
-	}
-}
-
 // mustLogFatal wraps log.Fatal() in a way that ensures the
 // output is always printed to stderr so the user can see it
 // if the user is still there, even if the process log was not
@@ -158,6 +136,25 @@ func defaultLoader(serverType string) (caddy.Input, error) {
 	}, nil
 }
 
+// logVersion logs the version that is starting.
+func logVersion() { log.Print("[INFO] " + versionString()) }
+
+// showVersion prints the version that is starting.
+func showVersion() {
+	if dnsserver.Quiet {
+		return
+	}
+	fmt.Print(versionString())
+	if devBuild && gitShortStat != "" {
+		fmt.Printf("%s\n%s\n", gitShortStat, gitFilesModified)
+	}
+}
+
+// versionString returns the CoreDNS version as a string.
+func versionString() string {
+	return fmt.Sprintf("%s-%s starting\n", caddy.AppName, caddy.AppVersion)
+}
+
 // setVersion figures out the version information
 // based on variables set by -ldflags.
 func setVersion() {