afero/iofs.go

139 lines
2.7 KiB
Go

// +build go1.16
package afero
import (
"io/fs"
"path"
)
// IOFS adopts afero.Fs to stdlib io/fs.FS
type IOFS struct {
Fs
}
func NewIOFS(fs Fs) IOFS {
return IOFS{Fs: fs}
}
var (
_ fs.FS = IOFS{}
_ fs.GlobFS = IOFS{}
_ fs.ReadDirFS = IOFS{}
_ fs.ReadFileFS = IOFS{}
_ fs.StatFS = IOFS{}
_ fs.SubFS = IOFS{}
)
func (iofs IOFS) Open(name string) (fs.File, error) {
const op = "open"
// by convention for fs.FS implementations we should perform this check
if !fs.ValidPath(name) {
return nil, iofs.wrapError(op, name, fs.ErrInvalid)
}
file, err := iofs.Fs.Open(name)
if err != nil {
return nil, iofs.wrapError(op, name, err)
}
// file should implement fs.ReadDirFile
if _, ok := file.(fs.ReadDirFile); !ok {
file = readDirFile{file}
}
return file, nil
}
func (iofs IOFS) Glob(pattern string) ([]string, error) {
const op = "glob"
// afero.Glob does not perform this check but it's required for implementations
if _, err := path.Match(pattern, ""); err != nil {
return nil, iofs.wrapError(op, pattern, err)
}
items, err := Glob(iofs.Fs, pattern)
if err != nil {
return nil, iofs.wrapError(op, pattern, err)
}
return items, nil
}
func (iofs IOFS) ReadDir(name string) ([]fs.DirEntry, error) {
items, err := ReadDir(iofs.Fs, name)
if err != nil {
return nil, iofs.wrapError("readdir", name, err)
}
ret := make([]fs.DirEntry, len(items))
for i := range items {
ret[i] = dirEntry{items[i]}
}
return ret, nil
}
func (iofs IOFS) ReadFile(name string) ([]byte, error) {
const op = "readfile"
if !fs.ValidPath(name) {
return nil, iofs.wrapError(op, name, fs.ErrInvalid)
}
bytes, err := ReadFile(iofs.Fs, name)
if err != nil {
return nil, iofs.wrapError(op, name, err)
}
return bytes, nil
}
func (iofs IOFS) Sub(dir string) (fs.FS, error) { return IOFS{NewBasePathFs(iofs.Fs, dir)}, nil }
func (IOFS) wrapError(op, path string, err error) error {
if _, ok := err.(*fs.PathError); ok {
return err // don't need to wrap again
}
return &fs.PathError{
Op: op,
Path: path,
Err: err,
}
}
// dirEntry provides adapter from os.FileInfo to fs.DirEntry
type dirEntry struct {
fs.FileInfo
}
var _ fs.DirEntry = dirEntry{}
func (d dirEntry) Type() fs.FileMode { return d.FileInfo.Mode().Type() }
func (d dirEntry) Info() (fs.FileInfo, error) { return d.FileInfo, nil }
// readDirFile provides adapter from afero.File to fs.ReadDirFile needed for correct Open
type readDirFile struct {
File
}
var _ fs.ReadDirFile = readDirFile{}
func (r readDirFile) ReadDir(n int) ([]fs.DirEntry, error) {
items, err := r.File.Readdir(n)
if err != nil {
return nil, err
}
ret := make([]fs.DirEntry, len(items))
for i := range items {
ret[i] = dirEntry{items[i]}
}
return ret, nil
}