Make server bind interface configurable.

Bind by default to 127.0.0.1. Previously it always bound to all interfaces.

Always have log message display that the server is available on the
interface to which it is bound, instead of the baseUrl.

Fixes #1097

commands/server.go

@@ -33,6 +33,7 @@ import (
 )
 
 var serverPort int
+var serverInterface string
 var serverWatch bool
 var serverAppend bool
 var disableLiveReload bool
@@ -49,7 +50,8 @@ serve them up.`,
 }
 
 func init() {
-	serverCmd.Flags().IntVarP(&serverPort, "port", "p", 1313, "port to run the server on")
+	serverCmd.Flags().IntVarP(&serverPort, "port", "p", 1313, "port on which the server will listen")
+	serverCmd.Flags().StringVarP(&serverInterface, "bind", "", "127.0.0.1", "interface to which the server will bind")
 	serverCmd.Flags().BoolVarP(&serverWatch, "watch", "w", false, "watch filesystem for changes and recreate as needed")
 	serverCmd.Flags().BoolVarP(&serverAppend, "appendPort", "", true, "append port to baseurl")
 	serverCmd.Flags().BoolVar(&disableLiveReload, "disableLiveReload", false, "watch without enabling live browser reload on rebuild")
@@ -69,7 +71,7 @@ func server(cmd *cobra.Command, args []string) {
 		viper.Set("Watch", true)
 	}
 
-	l, err := net.Listen("tcp", ":"+strconv.Itoa(serverPort))
+	l, err := net.Listen("tcp", net.JoinHostPort(serverInterface, strconv.Itoa(serverPort)))
 	if err == nil {
 		l.Close()
 	} else {
@@ -121,6 +123,7 @@ func serve(port int) {
 	httpFs := &afero.HttpFs{SourceFs: hugofs.DestinationFS}
 	fileserver := http.FileServer(httpFs.Dir(helpers.AbsPathify(viper.GetString("PublishDir"))))
 
+	// We're only interested in the path
 	u, err := url.Parse(viper.GetString("BaseURL"))
 	if err != nil {
 		jww.ERROR.Fatalf("Invalid BaseURL: %s", err)
@@ -131,11 +134,13 @@ func serve(port int) {
 		http.Handle(u.Path, http.StripPrefix(u.Path, fileserver))
 	}
 
+	u.Host = serverInterface
 	u.Scheme = "http"
 	jww.FEEDBACK.Printf("Web Server is available at %s\n", u.String())
 	fmt.Println("Press Ctrl+C to stop")
 
-	err = http.ListenAndServe(":"+strconv.Itoa(port), nil)
+	endpoint := net.JoinHostPort(serverInterface, strconv.Itoa(port))
+	err = http.ListenAndServe(endpoint, nil)
 	if err != nil {
 		jww.ERROR.Printf("Error: %s\n", err.Error())
 		os.Exit(1)