feat: new (optional) index file list for file system serve

fs.go

@@ -33,6 +33,7 @@ type FS struct {
 	UseLocalFolder    bool
 	LocalFolderPrefix string
 	HeaderHandler     HeaderHandler
+	IndexFilenames    []string
 }
 
 // NewFS creates a new instance of the http file system used for serving static files.
@@ -51,13 +52,13 @@ func (fs *FS) ServeHTTP(w http.ResponseWriter, r *http.Request, info RoutingInfo
 	}
 
 	// search for file in static file system
-	file, filePath, err := fs.findFile(url)
+	file, err := fs.findFile(url)
 	if err != nil {
 		http.NotFound(w, r)
 		return
 	}
 	// check, if the file is a folder
-	file, ok := fs.checkFolder(file, filePath)
+	file, ok := fs.checkFolder(file, url)
 	if !ok {
 		http.NotFound(w, r)
 		return
@@ -68,7 +69,7 @@ func (fs *FS) ServeHTTP(w http.ResponseWriter, r *http.Request, info RoutingInfo
 	fs.serve(w, r, info, file)
 }
 
-func (fs *FS) findFile(url string) (fs.File, string, error) {
+func (fs *FS) findFile(url string) (fs.File, error) {
 	// build file path
 	filePath := path.Join(fs.FolderPrefix, url)
 	filePath = strings.TrimPrefix(filePath, "/")
@@ -83,7 +84,7 @@ func (fs *FS) findFile(url string) (fs.File, string, error) {
 
 		file, err := os.Open(localFilePath)
 		if err == nil {
-			return file, localFilePath, nil
+			return file, nil
 		}
 	}
 
@@ -92,7 +93,7 @@ func (fs *FS) findFile(url string) (fs.File, string, error) {
 		filePath = "."
 	}
 	file, err := fs.StaticFiles.Open(filePath)
-	return file, filePath, err
+	return file, err
 }
 
 func (fs *FS) checkFolder(file fs.File, url string) (fs.File, bool) {
@@ -107,6 +108,14 @@ func (fs *FS) checkFolder(file fs.File, url string) (fs.File, bool) {
 		// close folder handler (we don't need it anymore)
 		_ = file.Close()
 
+		// check for index files
+		for _, indexFileName := range fs.IndexFilenames {
+			newFullPath := path.Join(url, indexFileName)
+			if newFile, err := fs.findFile(newFullPath); err == nil {
+				return newFile, true
+			}
+		}
+
 		return file, false
 	}
 

fs_test.go

@@ -156,6 +156,27 @@ func TestFSFolderLocal(t *testing.T) {
 	}
 }
 
+func TestFSFolderIndex(t *testing.T) {
+	// create new FS
+	fs := NewFS(&staticFiles)
+	fs.IndexFilenames = []string{"README.md"}
+
+	// serve the request
+	tw := &testWriter{}
+	tr := &http.Request{
+		Method: http.MethodHead,
+		URL: &url.URL{
+			Path: "/",
+		},
+	}
+	fs.ServeHTTP(tw, tr, RoutingInfo{})
+
+	// check data
+	if tw.statusCode != http.StatusOK {
+		t.Error("received invalid http status code", tw.statusCode)
+	}
+}
+
 func TestFSNotFound(t *testing.T) {
 	// create new FS
 	fs := NewFS(&staticFiles)