afero/gcsfs/file_info.go

138 lines
3.3 KiB
Go

// Copyright © 2021 Vasily Ovchinnikov <vasily@remerge.io>.
//
// The code in this file is derived from afero fork github.com/Zatte/afero by Mikael Rapp
// licensed under Apache License 2.0.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
package gcsfs
import (
"os"
"path/filepath"
"strings"
"time"
"cloud.google.com/go/storage"
)
const (
folderSize = 42
)
type FileInfo struct {
name string
size int64
updated time.Time
isDir bool
fileMode os.FileMode
}
func newFileInfo(name string, fs *GcsFs, fileMode os.FileMode) (*FileInfo, error) {
res := &FileInfo{
name: name,
size: folderSize,
updated: time.Time{},
isDir: false,
fileMode: fileMode,
}
obj := fs.getObj(name)
objAttrs, err := obj.Attrs(fs.ctx)
if err != nil {
if err.Error() == ErrEmptyObjectName.Error() {
// It's a root folder here, we return right away
res.name = fs.ensureTrailingSeparator(res.name)
res.isDir = true
return res, nil
} else if err.Error() == ErrObjectDoesNotExist.Error() {
// Folders do not actually "exist" in GCloud, so we have to check, if something exists with
// such a prefix
it := fs.bucket.Objects(
fs.ctx, &storage.Query{Delimiter: fs.separator, Prefix: name, Versions: false})
if _, err = it.Next(); err == nil {
res.name = fs.ensureTrailingSeparator(res.name)
res.isDir = true
return res, nil
}
return nil, ErrFileNotFound
}
return nil, err
}
res.size = objAttrs.Size
res.updated = objAttrs.Updated
return res, nil
}
func newFileInfoFromAttrs(objAttrs *storage.ObjectAttrs, fileMode os.FileMode) *FileInfo {
res := &FileInfo{
name: objAttrs.Name,
size: objAttrs.Size,
updated: objAttrs.Updated,
isDir: false,
fileMode: fileMode,
}
if res.name == "" {
if objAttrs.Prefix != "" {
// It's a virtual folder! It does not have a name, but prefix - this is how GCS API
// deals with them at the moment
res.name = objAttrs.Prefix
res.size = folderSize
res.isDir = true
}
}
return res
}
func (fi *FileInfo) Name() string {
return filepath.Base(fi.name)
}
func (fi *FileInfo) Size() int64 {
return fi.size
}
func (fi *FileInfo) Mode() os.FileMode {
if fi.IsDir() {
return os.ModeDir | fi.fileMode
}
return fi.fileMode
}
func (fi *FileInfo) ModTime() time.Time {
return fi.updated
}
func (fi *FileInfo) IsDir() bool {
return fi.isDir
}
func (fi *FileInfo) Sys() interface{} {
return nil
}
type ByName []*FileInfo
func (a ByName) Len() int { return len(a) }
func (a ByName) Swap(i, j int) {
a[i].name, a[j].name = a[j].name, a[i].name
a[i].size, a[j].size = a[j].size, a[i].size
a[i].updated, a[j].updated = a[j].updated, a[i].updated
a[i].isDir, a[j].isDir = a[j].isDir, a[i].isDir
}
func (a ByName) Less(i, j int) bool { return strings.Compare(a[i].Name(), a[j].Name()) == -1 }