Use helper to open file (not directory)

helpers.go

@@ -5,15 +5,12 @@ Miscellaneous helpers: logging, errors, subprocesses
 package main
 
 import (
+	"errors"
 	"fmt"
-	"io"
-	"io/ioutil"
 	"log"
 	"net/http"
-	"net/url"
 	"os"
 	"os/exec"
-	"strings"
 	"syscall"
 )
 
@@ -63,26 +60,38 @@ func cleanUpProcessGroup(cmd *exec.Cmd) {
 	cmd.Wait()
 }
 
-func forwardResponseToClient(w http.ResponseWriter, r *http.Response) {
-	log.Printf("PROXY:%s %q %d", r.Request.Method, r.Request.URL, r.StatusCode)
+func setNoCacheHeaders(header http.Header) {
+	header.Set("Cache-Control", "no-cache, no-store, max-age=0, must-revalidate")
+	header.Set("Pragma", "no-cache")
+	header.Set("Expires", "Fri, 01 Jan 1990 00:00:00 GMT")
+}
 
-	for k, v := range r.Header {
-		w.Header()[k] = v
+func openFile(path string) (file *os.File, fi os.FileInfo, err error) {
+	file, err = os.Open(path)
+	if err != nil {
+		return
 	}
 
-	w.WriteHeader(r.StatusCode)
-	io.Copy(w, r.Body)
-}
+	defer func() {
+		if err != nil {
+			file.Close()
+		}
+	}()
 
-func setHttpPostForm(r *http.Request, values url.Values) {
-	dataBuffer := strings.NewReader(values.Encode())
-	r.Body = ioutil.NopCloser(dataBuffer)
-	r.ContentLength = int64(dataBuffer.Len())
-	r.Header.Set("Content-Type", "application/x-www-form-urlencoded")
-}
+	fi, err = file.Stat()
+	if err != nil {
+		return
+	}
 
-func setNoCacheHeaders(header http.Header) {
-	header.Set("Cache-Control", "no-cache, no-store, max-age=0, must-revalidate")
-	header.Set("Pragma", "no-cache")
-	header.Set("Expires", "Fri, 01 Jan 1990 00:00:00 GMT")
+	// The os.Open can also open directories
+	if fi.IsDir() {
+		err = &os.PathError{
+			Op:   "open",
+			Path: path,
+			Err:  errors.New("path is directory"),
+		}
+		return
+	}
+
+	return
 }

sendfile.go

@@ -7,10 +7,8 @@ via the X-Sendfile mechanism. All that is needed in the Rails code is the
 package main
 
 import (
-	"fmt"
 	"log"
 	"net/http"
-	"os"
 )
 
 type sendFileResponseWriter struct {
@@ -65,19 +63,13 @@ func (s *sendFileResponseWriter) WriteHeader(status int) {
 
 	// Serve the file
 	log.Printf("SendFile: serving %q", file)
-	content, err := os.Open(file)
+	content, fi, err := openFile(file)
 	if err != nil {
 		http.NotFound(s.rw, s.req)
 		return
 	}
 	defer content.Close()
 
-	fi, err := content.Stat()
-	if err != nil || fi.IsDir() {
-		fail500(s.rw, fmt.Errorf("handleSendfile: get mtime: %v", err))
-		return
-	}
-
 	http.ServeContent(s.rw, s.req, "", fi.ModTime(), content)
 }
 

servefile.go

@@ -19,7 +19,7 @@ func handleServeFile(documentRoot *string, notFoundHandler serviceHandleFunc) se
 			return
 		}
 
-		content, err := os.Open(file)
+		content, fi, err := openFile(file)
 		if err != nil {
 			if notFoundHandler != nil {
 				notFoundHandler(w, r)
@@ -30,21 +30,6 @@ func handleServeFile(documentRoot *string, notFoundHandler serviceHandleFunc) se
 		}
 		defer content.Close()
 
-		fi, err := content.Stat()
-		if err != nil {
-			fail500(w, fmt.Errorf("handleServeFileHandler", err))
-			return
-		}
-
-		if fi.IsDir() {
-			if notFoundHandler != nil {
-				notFoundHandler(w, r)
-			} else {
-				http.NotFound(w, r.Request)
-			}
-			return
-		}
-
 		log.Printf("StaticFile: serving %q", file)
 		http.ServeContent(w, r.Request, filepath.Base(file), fi.ModTime(), content)
 	}