go-tour: fix static content serving

LGTM=hyangah
R=golang-codereviews, hyangah
CC=golang-codereviews
https://codereview.appspot.com/82430043

app.yaml

@@ -6,14 +6,17 @@ api_version: go1
 default_expiration: "7d"
 
 handlers:
+
+# Keep these static file handlers in sync with gotour/local.go.
 - url: /favicon.ico
   static_files: static/img/favicon.ico
   upload: static/img/favicon.ico
 - url: /content/img
   static_dir: content/img
-- url: /static/
+- url: /static
   static_dir: static
   application_readable: true
+
 - url: /(.*|list|lesson/.*|compile|fmt|script\.js)
   script: _go_app
 

gotour/local.go

@@ -100,10 +100,16 @@ func main() {
 	}
 
 	http.HandleFunc("/", rootHandler)
-	http.Handle("/static/", http.FileServer(http.Dir(root)))
 	http.HandleFunc("/lesson/", lessonHandler)
 	http.Handle(socketPath, socket.Handler)
 
+	// Keep these static file handlers in sync with ../app.yaml.
+	static := http.FileServer(http.Dir(root))
+	http.Handle("/content/img/", static)
+	http.Handle("/static/", static)
+	imgDir := filepath.Join(root, "static", "img")
+	http.Handle("/favicon.ico", http.FileServer(http.Dir(imgDir)))
+
 	go func() {
 		url := "http://" + httpAddr
 		if waitServer(url) && *openBrowser && startBrowser(url) {

static/css/app.css

@@ -273,7 +273,7 @@ ul {
         left: 0;
         width: 50%;
         overflow: hidden;
-        background-image: url(/img/gopher.png);
+        background-image: url(/static/img/gopher.png);
         background-repeat: no-repeat;
         background-position: bottom;
         background-color: #fafafa;