package vfsutil
import (
"io"
"net/http"
"os"
pathpkg "path"
"path/filepath"
"sort"
)
// Walk walks the filesystem rooted at root, calling walkFn for each file or
// directory in the filesystem, including root. All errors that arise visiting files
// and directories are filtered by walkFn. The files are walked in lexical
// order.
func Walk(fs http.FileSystem, root string, walkFn filepath.WalkFunc) error {
info, err := Stat(fs, root)
if err != nil {
return walkFn(root, nil, err)
}
return walk(fs, root, info, walkFn)
}
// readDirNames reads the directory named by dirname and returns
// a sorted list of directory entries.
func readDirNames(fs http.FileSystem, dirname string) ([]string, error) {
fis, err := ReadDir(fs, dirname)
if err != nil {
return nil, err
}
names := make([]string, len(fis))
for i := range fis {
names[i] = fis[i].Name()
}
sort.Strings(names)
return names, nil
}
// walk recursively descends path, calling walkFn.
func walk(fs http.FileSystem, path string, info os.FileInfo, walkFn filepath.WalkFunc) error {
err := walkFn(path, info, nil)
if err != nil {
if info.IsDir() && err == filepath.SkipDir {
return nil
}
return err
}
if !info.IsDir() {
return nil
}
names, err := readDirNames(fs, path)
if err != nil {
return walkFn(path, info, err)
}
for _, name := range names {
filename := pathpkg.Join(path, name)
fileInfo, err := Stat(fs, filename)
if err != nil {
if err := walkFn(filename, fileInfo, err); err != nil && err != filepath.SkipDir {
return err
}
} else {
err = walk(fs, filename, fileInfo, walkFn)
if err != nil {
if !fileInfo.IsDir() || err != filepath.SkipDir {
return err
}
}
}
}
return nil
}
// WalkFilesFunc is the type of the function called for each file or directory visited by WalkFiles.
// It's like filepath.WalkFunc, except it provides an additional ReadSeeker parameter for file being visited.
type WalkFilesFunc func(path string, info os.FileInfo, rs io.ReadSeeker, err error) error
// WalkFiles walks the filesystem rooted at root, calling walkFn for each file or
// directory in the filesystem, including root. In addition to FileInfo, it passes an
// ReadSeeker to walkFn for each file it visits.
func WalkFiles(fs http.FileSystem, root string, walkFn WalkFilesFunc) error {
file, info, err := openStat(fs, root)
if err != nil {
return walkFn(root, nil, nil, err)
}
return walkFiles(fs, root, info, file, walkFn)
}
// walkFiles recursively descends path, calling walkFn.
// It closes the input file after it's done with it, so the caller shouldn't.
func walkFiles(fs http.FileSystem, path string, info os.FileInfo, file http.File, walkFn WalkFilesFunc) error {
err := walkFn(path, info, file, nil)
file.Close()
if err != nil {
if info.IsDir() && err == filepath.SkipDir {
return nil
}
return err
}
if !info.IsDir() {
return nil
}
names, err := readDirNames(fs, path)
if err != nil {
return walkFn(path, info, nil, err)
}
for _, name := range names {
filename := pathpkg.Join(path, name)
file, fileInfo, err := openStat(fs, filename)
if err != nil {
if err := walkFn(filename, nil, nil, err); err != nil && err != filepath.SkipDir {
return err
}
} else {
err = walkFiles(fs, filename, fileInfo, file, walkFn)
// file is closed by walkFiles, so we don't need to close it here.
if err != nil {
if !fileInfo.IsDir() || err != filepath.SkipDir {
return err
}
}
}
}
return nil
}
// openStat performs Open and Stat and returns results, or first error encountered.
// The caller is responsible for closing the returned file when done.
func openStat(fs http.FileSystem, name string) (http.File, os.FileInfo, error) {
f, err := fs.Open(name)
if err != nil {
return nil, nil, err
}
fi, err := f.Stat()
if err != nil {
f.Close()
return nil, nil, err
}
return f, fi, nil
}
