cmd/present: embed static and template files

cmd/present/dir.go

@@ -7,6 +7,7 @@ package main
 import (
 	"html/template"
 	"io"
+	"io/fs"
 	"log"
 	"net"
 	"net/http"
@@ -18,10 +19,6 @@ import (
 	"golang.org/x/tools/present"
 )
 
-func init() {
-	http.HandleFunc("/", dirHandler)
-}
-
 // dirHandler serves a directory listing for the requested path, rooted at *contentPath.
 func dirHandler(w http.ResponseWriter, r *http.Request) {
 	if r.URL.Path == "/favicon.ico" {
@@ -65,29 +62,29 @@ var (
 	contentTemplate map[string]*template.Template
 )
 
-func initTemplates(base string) error {
+func initTemplates(fs fs.FS) error {
 	// Locate the template file.
-	actionTmpl := filepath.Join(base, "templates/action.tmpl")
+	actionTmpl := "templates/action.tmpl"
 
 	contentTemplate = make(map[string]*template.Template)
 
 	for ext, contentTmpl := range map[string]string{
 		".slide":   "slides.tmpl",
 		".article": "article.tmpl",
 	} {
-		contentTmpl = filepath.Join(base, "templates", contentTmpl)
+		contentTmpl = filepath.Join("templates", contentTmpl)
 
 		// Read and parse the input.
 		tmpl := present.Template()
 		tmpl = tmpl.Funcs(template.FuncMap{"playable": playable})
-		if _, err := tmpl.ParseFiles(actionTmpl, contentTmpl); err != nil {
+		if _, err := tmpl.ParseFS(fs, actionTmpl, contentTmpl); err != nil {
 			return err
 		}
 		contentTemplate[ext] = tmpl
 	}
 
 	var err error
-	dirListTemplate, err = template.ParseFiles(filepath.Join(base, "templates/dir.tmpl"))
+	dirListTemplate, err = template.ParseFS(fs, "templates/dir.tmpl")
 	return err
 }
 

cmd/present/main.go

@@ -5,9 +5,10 @@
 package main
 
 import (
+	"embed"
 	"flag"
 	"fmt"
-	"go/build"
+	"io/fs"
 	"log"
 	"net"
 	"net/http"
@@ -50,16 +51,25 @@ func main() {
 		*contentPath = "./content/"
 	}
 
-	if *basePath == "" {
-		p, err := build.Default.Import(basePkg, "", build.FindOnly)
+	baseFS := func() fs.FS {
+		if *basePath != "" {
+			return os.DirFS(*basePath)
+		}
+		//go:embed base
+		var staticFS embed.FS
+
+		// by default, lets use the embedded files.
+		fs, err := fs.Sub(staticFS, "base")
 		if err != nil {
-			fmt.Fprintf(os.Stderr, "Couldn't find gopresent files: %v\n", err)
-			fmt.Fprintf(os.Stderr, basePathMessage, basePkg)
-			os.Exit(1)
+			panic(err)
 		}
-		*basePath = p.Dir
-	}
-	err := initTemplates(*basePath)
+
+		return fs
+	}()
+
+	http.HandleFunc("/", dirHandler)
+
+	err := initTemplates(baseFS)
 	if err != nil {
 		log.Fatalf("Failed to parse templates: %v", err)
 	}
@@ -98,8 +108,8 @@ func main() {
 		}
 	}
 
-	initPlayground(*basePath, origin)
-	http.Handle("/static/", http.FileServer(http.Dir(*basePath)))
+	initPlayground(baseFS, origin)
+	http.Handle("/static/", http.FileServer(http.FS(baseFS)))
 
 	if !ln.Addr().(*net.TCPAddr).IP.IsLoopback() &&
 		present.PlayEnabled && !*nativeClient && !*usePlayground {

cmd/present/play.go

@@ -7,6 +7,7 @@ package main
 import (
 	"bytes"
 	"fmt"
+	"io/fs"
 	"io/ioutil"
 	"net/http"
 	"net/url"
@@ -31,18 +32,27 @@ var scripts = []string{"jquery.js", "jquery-ui.js", "playground.js", "play.js"}
 // playScript registers an HTTP handler at /play.js that serves all the
 // scripts specified by the variable above, and appends a line that
 // initializes the playground with the specified transport.
-func playScript(root, transport string) {
+// func playScript(root, transport string) {
+func playScript(fs fs.FS, transport string) {
 	modTime := time.Now()
 	var buf bytes.Buffer
 	for _, p := range scripts {
 		if s, ok := static.Files[p]; ok {
 			buf.WriteString(s)
 			continue
 		}
-		b, err := ioutil.ReadFile(filepath.Join(root, "static", p))
+
+		f, err := fs.Open(filepath.Join("static", p))
+		if err != nil {
+			panic(err)
+		}
+		defer f.Close()
+
+		b, err := ioutil.ReadAll(f)
 		if err != nil {
 			panic(err)
 		}
+
 		buf.Write(b)
 	}
 	fmt.Fprintf(&buf, "\ninitPlayground(new %v());\n", transport)
@@ -53,12 +63,13 @@ func playScript(root, transport string) {
 	})
 }
 
-func initPlayground(basepath string, origin *url.URL) {
+// func initPlayground(basepath string, origin *url.URL) {
+func initPlayground(fs fs.FS, origin *url.URL) {
 	if !present.PlayEnabled {
 		return
 	}
 	if *usePlayground {
-		playScript(basepath, "HTTPTransport")
+		playScript(fs, "HTTPTransport")
 		return
 	}
 
@@ -73,7 +84,7 @@ func initPlayground(basepath string, origin *url.URL) {
 			return environ("GOOS=nacl")
 		}
 	}
-	playScript(basepath, "SocketTransport")
+	playScript(fs, "SocketTransport")
 	http.Handle("/socket", socket.NewHandler(origin))
 }