webdav: move recursive PROPFIND to backend

Closes: https://github.com/emersion/go-webdav/issues/22

fs_local.go

@@ -25,6 +25,15 @@ func (fs LocalFileSystem) path(name string) (string, error) {
 	return filepath.Join(string(fs), filepath.FromSlash(name)), nil
 }
 
+func (fs LocalFileSystem) href(path string) (string, error) {
+	rel, err := filepath.Rel(string(fs), path)
+	if err != nil {
+		return "", err
+	}
+	href := "/" + filepath.ToSlash(rel)
+	return href, nil
+}
+
 func (fs LocalFileSystem) Open(name string) (io.ReadCloser, error) {
 	p, err := fs.path(name)
 	if err != nil {
@@ -56,27 +65,31 @@ func (fs LocalFileSystem) Stat(name string) (*FileInfo, error) {
 	return fileInfoFromOS(name, fi), nil
 }
 
-func (fs LocalFileSystem) Readdir(name string) ([]FileInfo, error) {
+func (fs LocalFileSystem) Readdir(name string, recursive bool) ([]FileInfo, error) {
 	p, err := fs.path(name)
 	if err != nil {
 		return nil, err
 	}
-	f, err := os.Open(p)
-	if err != nil {
-		return nil, err
-	}
-	defer f.Close()
 
-	fis, err := f.Readdir(-1)
+	var l []FileInfo
+	err = filepath.Walk(p, func(p string, fi os.FileInfo, err error) error {
 		if err != nil {
-		return nil, err
+			return err
 		}
 
-	l := make([]FileInfo, len(fis))
+		href, err := fs.href(p)
-	for i, fi := range fis {
+		if err != nil {
-		l[i] = *fileInfoFromOS(path.Join(name, fi.Name()), fi)
+			return err
 		}
-	return l, nil
+
+		l = append(l, *fileInfoFromOS(href, fi))
+
+		if !recursive && fi.IsDir() {
+			return filepath.SkipDir
+		}
+		return nil
+	})
+	return l, err
 }
 
 func (fs LocalFileSystem) Create(name string) (io.WriteCloser, error) {

server.go

@@ -14,7 +14,7 @@ import (
 type FileSystem interface {
 	Open(name string) (io.ReadCloser, error)
 	Stat(name string) (*FileInfo, error)
-	Readdir(name string) ([]FileInfo, error)
+	Readdir(name string, recursive bool) ([]FileInfo, error)
 	Create(name string) (io.WriteCloser, error)
 	RemoveAll(name string) error
 	Mkdir(name string) error
@@ -106,6 +106,8 @@ func (b *backend) HeadGet(w http.ResponseWriter, r *http.Request) error {
 }
 
 func (b *backend) Propfind(r *http.Request, propfind *internal.Propfind, depth internal.Depth) (*internal.Multistatus, error) {
+	// TODO: use partial error Response on error
+
 	fi, err := b.FileSystem.Stat(r.URL.Path)
 	if os.IsNotExist(err) {
 		return nil, &internal.HTTPError{Code: http.StatusNotFound, Err: err}
@@ -114,41 +116,30 @@ func (b *backend) Propfind(r *http.Request, propfind *internal.Propfind, depth i
 	}
 
 	var resps []internal.Response
-	if err := b.propfind(propfind, fi, depth, &resps); err != nil {
+	if depth != internal.DepthZero && fi.IsDir {
+		children, err := b.FileSystem.Readdir(r.URL.Path, depth == internal.DepthInfinity)
+		if err != nil {
 			return nil, err
 		}
 
-	return internal.NewMultistatus(resps...), nil
+		resps = make([]internal.Response, len(children))
-}
+		for i, child := range children {
-
+			resp, err := b.propfindFile(propfind, &child)
-func (b *backend) propfind(propfind *internal.Propfind, fi *FileInfo, depth internal.Depth, resps *[]internal.Response) error {
+			if err != nil {
-	// TODO: use partial error Response on error
+				return nil, err
-
+			}
+			resps[i] = *resp
+		}
+	} else {
 		resp, err := b.propfindFile(propfind, fi)
 		if err != nil {
-		return err
+			return nil, err
-	}
-	*resps = append(*resps, *resp)
-
-	if depth != internal.DepthZero && fi.IsDir {
-		childDepth := depth
-		if depth == internal.DepthOne {
-			childDepth = internal.DepthZero
 		}
 
-		children, err := b.FileSystem.Readdir(fi.Href)
+		resps = []internal.Response{*resp}
-		if err != nil {
-			return err
 	}
 
-		for _, child := range children {
+	return internal.NewMultistatus(resps...), nil
-			if err := b.propfind(propfind, &child, childDepth, resps); err != nil {
-				return err
-			}
-		}
-	}
-
-	return nil
 }
 
 func (b *backend) propfindFile(propfind *internal.Propfind, fi *FileInfo) (*internal.Response, error) {