go-tour: honor -http argument in websocket code

R=golang-dev, dsymonds
CC=golang-dev
https://codereview.appspot.com/7305094

gotour/appengine.go

@@ -94,3 +94,7 @@ func prepContent(in io.Reader) io.Reader {
 	}()
 	return out
 }
+
+// socketAddr returns the WebSocket handler address.
+// The App Engine version does not provide a WebSocket handler.
+func socketAddr() string { return "" }

gotour/local.go

@@ -29,7 +29,10 @@ import (
 	_ "code.google.com/p/go-tour/wc"
 )
 
-const basePkg = "code.google.com/p/go-tour/"
+const (
+	basePkg    = "code.google.com/p/go-tour/"
+	socketPath = "/socket"
+)
 
 var (
 	httpListen  = flag.String("http", "127.0.0.1:3999", "host:port to listen on")
@@ -43,6 +46,8 @@ var (
 
 	// GOPATH containing the tour packages
 	gopath = os.Getenv("GOPATH")
+
+	httpAddr string
 )
 
 func isRoot(path string) bool {
@@ -99,7 +104,7 @@ func main() {
 		http.Error(w, "not found", 404)
 	})
 
-	http.Handle("/socket", socket.Handler)
+	http.Handle(socketPath, socket.Handler)
 
 	err = serveScripts(filepath.Join(root, "js"), "socket.js")
 	if err != nil {
@@ -117,7 +122,7 @@ func main() {
 		log.Print(localhostWarning)
 	}
 
-	httpAddr := host + ":" + port
+	httpAddr = host + ":" + port
 	go func() {
 		url := "http://" + httpAddr
 		if waitServer(url) && *openBrowser && startBrowser(url) {
@@ -196,3 +201,6 @@ func startBrowser(url string) bool {
 
 // prepContent for the local tour simply returns the content as-is.
 func prepContent(r io.Reader) io.Reader { return r }
+
+// socketAddr returns the WebSocket handler address.
+func socketAddr() string { return "ws://" + httpAddr + socketPath }

gotour/tour.go

@@ -40,7 +40,7 @@ func renderTour(w io.Writer, root string) error {
 	// Set up templates.
 	action := filepath.Join(root, "template", "action.tmpl")
 	tour := filepath.Join(root, "template", "tour.tmpl")
-	t := present.Template().Funcs(template.FuncMap{"nocode": nocode})
+	t := present.Template().Funcs(template.FuncMap{"nocode": nocode, "socketAddr": socketAddr})
 	_, err = t.ParseFiles(action, tour)
 	if err != nil {
 		return err
@@ -61,8 +61,6 @@ func nocode(s present.Section) bool {
 	return true
 }
 
-// TODO(adg): move these scripts out of static and into a dedicated js folder.
-
 var commonScripts = []string{
 	"jquery.js",
 	"codemirror/lib/codemirror.js",

js/tour.js

@@ -364,7 +364,7 @@ function setcookie(name, value, expire) {
 }
 
 if (window.connectPlayground) {
-	runFunc = window.connectPlayground("ws://localhost:3999/socket");
+	runFunc = window.connectPlayground(window.socketAddr);
 } else {
 	// If this message is logged,
 	// we have neglected to include socket.js or playground.js.

template/tour.tmpl

@@ -10,6 +10,9 @@
 
 <link rel="stylesheet" href="/static/codemirror/lib/codemirror.css">
 <link rel="stylesheet" href="static/tour.css">
+<script>
+window.socketAddr = "{{socketAddr}}";
+</script>
 <script src="/script.js"></script>
 
 </head>