rclone/backend/googlecloudstorage/googlecloudstorage.go

897 lines
24 KiB
Go

// Package googlecloudstorage provides an interface to Google Cloud Storage
package googlecloudstorage
/*
Notes
Can't set Updated but can set Metadata on object creation
Patch needs full_control not just read_write
FIXME Patch/Delete/Get isn't working with files with spaces in - giving 404 error
- https://code.google.com/p/google-api-go-client/issues/detail?id=64
*/
import (
"encoding/base64"
"encoding/hex"
"fmt"
"io"
"io/ioutil"
"log"
"net/http"
"os"
"path"
"regexp"
"strings"
"sync"
"time"
"github.com/ncw/rclone/fs"
"github.com/ncw/rclone/fs/config"
"github.com/ncw/rclone/fs/config/flags"
"github.com/ncw/rclone/fs/config/obscure"
"github.com/ncw/rclone/fs/fshttp"
"github.com/ncw/rclone/fs/hash"
"github.com/ncw/rclone/fs/walk"
"github.com/ncw/rclone/lib/oauthutil"
"github.com/pkg/errors"
"golang.org/x/oauth2"
"golang.org/x/oauth2/google"
"google.golang.org/api/googleapi"
storage "google.golang.org/api/storage/v1"
)
const (
rcloneClientID = "202264815644.apps.googleusercontent.com"
rcloneEncryptedClientSecret = "Uj7C9jGfb9gmeaV70Lh058cNkWvepr-Es9sBm0zdgil7JaOWF1VySw"
timeFormatIn = time.RFC3339
timeFormatOut = "2006-01-02T15:04:05.000000000Z07:00"
metaMtime = "mtime" // key to store mtime under in metadata
listChunks = 1000 // chunk size to read directory listings
)
var (
gcsLocation = flags.StringP("gcs-location", "", "", "Default location for buckets (us|eu|asia|us-central1|us-east1|us-east4|us-west1|asia-east1|asia-noetheast1|asia-southeast1|australia-southeast1|europe-west1|europe-west2).")
gcsStorageClass = flags.StringP("gcs-storage-class", "", "", "Default storage class for buckets (MULTI_REGIONAL|REGIONAL|STANDARD|NEARLINE|COLDLINE|DURABLE_REDUCED_AVAILABILITY).")
// Description of how to auth for this app
storageConfig = &oauth2.Config{
Scopes: []string{storage.DevstorageFullControlScope},
Endpoint: google.Endpoint,
ClientID: rcloneClientID,
ClientSecret: obscure.MustReveal(rcloneEncryptedClientSecret),
RedirectURL: oauthutil.TitleBarRedirectURL,
}
)
// Register with Fs
func init() {
fs.Register(&fs.RegInfo{
Name: "google cloud storage",
Description: "Google Cloud Storage (this is not Google Drive)",
NewFs: NewFs,
Config: func(name string) {
if config.FileGet(name, "service_account_file") != "" {
return
}
err := oauthutil.Config("google cloud storage", name, storageConfig)
if err != nil {
log.Fatalf("Failed to configure token: %v", err)
}
},
Options: []fs.Option{{
Name: config.ConfigClientID,
Help: "Google Application Client Id - leave blank normally.",
}, {
Name: config.ConfigClientSecret,
Help: "Google Application Client Secret - leave blank normally.",
}, {
Name: "project_number",
Help: "Project number optional - needed only for list/create/delete buckets - see your developer console.",
}, {
Name: "service_account_file",
Help: "Service Account Credentials JSON file path - needed only if you want use SA instead of interactive login.",
}, {
Name: "object_acl",
Help: "Access Control List for new objects.",
Examples: []fs.OptionExample{{
Value: "authenticatedRead",
Help: "Object owner gets OWNER access, and all Authenticated Users get READER access.",
}, {
Value: "bucketOwnerFullControl",
Help: "Object owner gets OWNER access, and project team owners get OWNER access.",
}, {
Value: "bucketOwnerRead",
Help: "Object owner gets OWNER access, and project team owners get READER access.",
}, {
Value: "private",
Help: "Object owner gets OWNER access [default if left blank].",
}, {
Value: "projectPrivate",
Help: "Object owner gets OWNER access, and project team members get access according to their roles.",
}, {
Value: "publicRead",
Help: "Object owner gets OWNER access, and all Users get READER access.",
}},
}, {
Name: "bucket_acl",
Help: "Access Control List for new buckets.",
Examples: []fs.OptionExample{{
Value: "authenticatedRead",
Help: "Project team owners get OWNER access, and all Authenticated Users get READER access.",
}, {
Value: "private",
Help: "Project team owners get OWNER access [default if left blank].",
}, {
Value: "projectPrivate",
Help: "Project team members get access according to their roles.",
}, {
Value: "publicRead",
Help: "Project team owners get OWNER access, and all Users get READER access.",
}, {
Value: "publicReadWrite",
Help: "Project team owners get OWNER access, and all Users get WRITER access.",
}},
}, {
Name: "location",
Help: "Location for the newly created buckets.",
Examples: []fs.OptionExample{{
Value: "",
Help: "Empty for default location (US).",
}, {
Value: "asia",
Help: "Multi-regional location for Asia.",
}, {
Value: "eu",
Help: "Multi-regional location for Europe.",
}, {
Value: "us",
Help: "Multi-regional location for United States.",
}, {
Value: "asia-east1",
Help: "Taiwan.",
}, {
Value: "asia-northeast1",
Help: "Tokyo.",
}, {
Value: "asia-southeast1",
Help: "Singapore.",
}, {
Value: "australia-southeast1",
Help: "Sydney.",
}, {
Value: "europe-west1",
Help: "Belgium.",
}, {
Value: "europe-west2",
Help: "London.",
}, {
Value: "us-central1",
Help: "Iowa.",
}, {
Value: "us-east1",
Help: "South Carolina.",
}, {
Value: "us-east4",
Help: "Northern Virginia.",
}, {
Value: "us-west1",
Help: "Oregon.",
}},
}, {
Name: "storage_class",
Help: "The storage class to use when storing objects in Google Cloud Storage.",
Examples: []fs.OptionExample{{
Value: "",
Help: "Default",
}, {
Value: "MULTI_REGIONAL",
Help: "Multi-regional storage class",
}, {
Value: "REGIONAL",
Help: "Regional storage class",
}, {
Value: "NEARLINE",
Help: "Nearline storage class",
}, {
Value: "COLDLINE",
Help: "Coldline storage class",
}, {
Value: "DURABLE_REDUCED_AVAILABILITY",
Help: "Durable reduced availability storage class",
}},
}},
})
}
// Fs represents a remote storage server
type Fs struct {
name string // name of this remote
root string // the path we are working on if any
features *fs.Features // optional features
svc *storage.Service // the connection to the storage server
client *http.Client // authorized client
bucket string // the bucket we are working on
bucketOKMu sync.Mutex // mutex to protect bucket OK
bucketOK bool // true if we have created the bucket
projectNumber string // used for finding buckets
objectACL string // used when creating new objects
bucketACL string // used when creating new buckets
location string // location of new buckets
storageClass string // storage class of new buckets
}
// Object describes a storage object
//
// Will definitely have info but maybe not meta
type Object struct {
fs *Fs // what this object is part of
remote string // The remote path
url string // download path
md5sum string // The MD5Sum of the object
bytes int64 // Bytes in the object
modTime time.Time // Modified time of the object
mimeType string
}
// ------------------------------------------------------------
// Name of the remote (as passed into NewFs)
func (f *Fs) Name() string {
return f.name
}
// Root of the remote (as passed into NewFs)
func (f *Fs) Root() string {
if f.root == "" {
return f.bucket
}
return f.bucket + "/" + f.root
}
// String converts this Fs to a string
func (f *Fs) String() string {
if f.root == "" {
return fmt.Sprintf("Storage bucket %s", f.bucket)
}
return fmt.Sprintf("Storage bucket %s path %s", f.bucket, f.root)
}
// Features returns the optional features of this Fs
func (f *Fs) Features() *fs.Features {
return f.features
}
// Pattern to match a storage path
var matcher = regexp.MustCompile(`^([^/]*)(.*)$`)
// parseParse parses a storage 'url'
func parsePath(path string) (bucket, directory string, err error) {
parts := matcher.FindStringSubmatch(path)
if parts == nil {
err = errors.Errorf("couldn't find bucket in storage path %q", path)
} else {
bucket, directory = parts[1], parts[2]
directory = strings.Trim(directory, "/")
}
return
}
func getServiceAccountClient(keyJsonfilePath string) (*http.Client, error) {
data, err := ioutil.ReadFile(os.ExpandEnv(keyJsonfilePath))
if err != nil {
return nil, errors.Wrap(err, "error opening credentials file")
}
conf, err := google.JWTConfigFromJSON(data, storageConfig.Scopes...)
if err != nil {
return nil, errors.Wrap(err, "error processing credentials")
}
ctxWithSpecialClient := oauthutil.Context(fshttp.NewClient(fs.Config))
return oauth2.NewClient(ctxWithSpecialClient, conf.TokenSource(ctxWithSpecialClient)), nil
}
// NewFs contstructs an Fs from the path, bucket:path
func NewFs(name, root string) (fs.Fs, error) {
var oAuthClient *http.Client
var err error
serviceAccountPath := config.FileGet(name, "service_account_file")
if serviceAccountPath != "" {
oAuthClient, err = getServiceAccountClient(serviceAccountPath)
if err != nil {
log.Fatalf("Failed configuring Google Cloud Storage Service Account: %v", err)
}
} else {
oAuthClient, _, err = oauthutil.NewClient(name, storageConfig)
if err != nil {
log.Fatalf("Failed to configure Google Cloud Storage: %v", err)
}
}
bucket, directory, err := parsePath(root)
if err != nil {
return nil, err
}
f := &Fs{
name: name,
bucket: bucket,
root: directory,
projectNumber: config.FileGet(name, "project_number"),
objectACL: config.FileGet(name, "object_acl"),
bucketACL: config.FileGet(name, "bucket_acl"),
location: config.FileGet(name, "location"),
storageClass: config.FileGet(name, "storage_class"),
}
f.features = (&fs.Features{
ReadMimeType: true,
WriteMimeType: true,
BucketBased: true,
}).Fill(f)
if f.objectACL == "" {
f.objectACL = "private"
}
if f.bucketACL == "" {
f.bucketACL = "private"
}
if *gcsLocation != "" {
f.location = *gcsLocation
}
if *gcsStorageClass != "" {
f.storageClass = *gcsStorageClass
}
// Create a new authorized Drive client.
f.client = oAuthClient
f.svc, err = storage.New(f.client)
if err != nil {
return nil, errors.Wrap(err, "couldn't create Google Cloud Storage client")
}
if f.root != "" {
f.root += "/"
// Check to see if the object exists
_, err = f.svc.Objects.Get(bucket, directory).Do()
if err == nil {
f.root = path.Dir(directory)
if f.root == "." {
f.root = ""
} else {
f.root += "/"
}
// return an error with an fs which points to the parent
return f, fs.ErrorIsFile
}
}
return f, nil
}
// Return an Object from a path
//
// If it can't be found it returns the error fs.ErrorObjectNotFound.
func (f *Fs) newObjectWithInfo(remote string, info *storage.Object) (fs.Object, error) {
o := &Object{
fs: f,
remote: remote,
}
if info != nil {
o.setMetaData(info)
} else {
err := o.readMetaData() // reads info and meta, returning an error
if err != nil {
return nil, err
}
}
return o, nil
}
// NewObject finds the Object at remote. If it can't be found
// it returns the error fs.ErrorObjectNotFound.
func (f *Fs) NewObject(remote string) (fs.Object, error) {
return f.newObjectWithInfo(remote, nil)
}
// listFn is called from list to handle an object.
type listFn func(remote string, object *storage.Object, isDirectory bool) error
// list the objects into the function supplied
//
// dir is the starting directory, "" for root
//
// Set recurse to read sub directories
func (f *Fs) list(dir string, recurse bool, fn listFn) error {
root := f.root
rootLength := len(root)
if dir != "" {
root += dir + "/"
}
list := f.svc.Objects.List(f.bucket).Prefix(root).MaxResults(listChunks)
if !recurse {
list = list.Delimiter("/")
}
for {
objects, err := list.Do()
if err != nil {
if gErr, ok := err.(*googleapi.Error); ok {
if gErr.Code == http.StatusNotFound {
err = fs.ErrorDirNotFound
}
}
return err
}
if !recurse {
var object storage.Object
for _, prefix := range objects.Prefixes {
if !strings.HasSuffix(prefix, "/") {
continue
}
err = fn(prefix[rootLength:len(prefix)-1], &object, true)
if err != nil {
return err
}
}
}
for _, object := range objects.Items {
if !strings.HasPrefix(object.Name, root) {
fs.Logf(f, "Odd name received %q", object.Name)
continue
}
remote := object.Name[rootLength:]
// is this a directory marker?
if (strings.HasSuffix(remote, "/") || remote == "") && object.Size == 0 {
if recurse {
// add a directory in if --fast-list since will have no prefixes
err = fn(remote[:len(remote)-1], object, true)
if err != nil {
return err
}
}
continue // skip directory marker
}
err = fn(remote, object, false)
if err != nil {
return err
}
}
if objects.NextPageToken == "" {
break
}
list.PageToken(objects.NextPageToken)
}
return nil
}
// Convert a list item into a DirEntry
func (f *Fs) itemToDirEntry(remote string, object *storage.Object, isDirectory bool) (fs.DirEntry, error) {
if isDirectory {
d := fs.NewDir(remote, time.Time{}).SetSize(int64(object.Size))
return d, nil
}
o, err := f.newObjectWithInfo(remote, object)
if err != nil {
return nil, err
}
return o, nil
}
// mark the bucket as being OK
func (f *Fs) markBucketOK() {
if f.bucket != "" {
f.bucketOKMu.Lock()
f.bucketOK = true
f.bucketOKMu.Unlock()
}
}
// listDir lists a single directory
func (f *Fs) listDir(dir string) (entries fs.DirEntries, err error) {
// List the objects
err = f.list(dir, false, func(remote string, object *storage.Object, isDirectory bool) error {
entry, err := f.itemToDirEntry(remote, object, isDirectory)
if err != nil {
return err
}
if entry != nil {
entries = append(entries, entry)
}
return nil
})
if err != nil {
return nil, err
}
// bucket must be present if listing succeeded
f.markBucketOK()
return entries, err
}
// listBuckets lists the buckets
func (f *Fs) listBuckets(dir string) (entries fs.DirEntries, err error) {
if dir != "" {
return nil, fs.ErrorListBucketRequired
}
if f.projectNumber == "" {
return nil, errors.New("can't list buckets without project number")
}
listBuckets := f.svc.Buckets.List(f.projectNumber).MaxResults(listChunks)
for {
buckets, err := listBuckets.Do()
if err != nil {
return nil, err
}
for _, bucket := range buckets.Items {
d := fs.NewDir(bucket.Name, time.Time{})
entries = append(entries, d)
}
if buckets.NextPageToken == "" {
break
}
listBuckets.PageToken(buckets.NextPageToken)
}
return entries, nil
}
// List the objects and directories in dir into entries. The
// entries can be returned in any order but should be for a
// complete directory.
//
// dir should be "" to list the root, and should not have
// trailing slashes.
//
// This should return ErrDirNotFound if the directory isn't
// found.
func (f *Fs) List(dir string) (entries fs.DirEntries, err error) {
if f.bucket == "" {
return f.listBuckets(dir)
}
return f.listDir(dir)
}
// ListR lists the objects and directories of the Fs starting
// from dir recursively into out.
//
// dir should be "" to start from the root, and should not
// have trailing slashes.
//
// This should return ErrDirNotFound if the directory isn't
// found.
//
// It should call callback for each tranche of entries read.
// These need not be returned in any particular order. If
// callback returns an error then the listing will stop
// immediately.
//
// Don't implement this unless you have a more efficient way
// of listing recursively that doing a directory traversal.
func (f *Fs) ListR(dir string, callback fs.ListRCallback) (err error) {
if f.bucket == "" {
return fs.ErrorListBucketRequired
}
list := walk.NewListRHelper(callback)
err = f.list(dir, true, func(remote string, object *storage.Object, isDirectory bool) error {
entry, err := f.itemToDirEntry(remote, object, isDirectory)
if err != nil {
return err
}
return list.Add(entry)
})
if err != nil {
return err
}
// bucket must be present if listing succeeded
f.markBucketOK()
return list.Flush()
}
// Put the object into the bucket
//
// Copy the reader in to the new object which is returned
//
// The new object may have been created if an error is returned
func (f *Fs) Put(in io.Reader, src fs.ObjectInfo, options ...fs.OpenOption) (fs.Object, error) {
// Temporary Object under construction
o := &Object{
fs: f,
remote: src.Remote(),
}
return o, o.Update(in, src, options...)
}
// PutStream uploads to the remote path with the modTime given of indeterminate size
func (f *Fs) PutStream(in io.Reader, src fs.ObjectInfo, options ...fs.OpenOption) (fs.Object, error) {
return f.Put(in, src, options...)
}
// Mkdir creates the bucket if it doesn't exist
func (f *Fs) Mkdir(dir string) error {
f.bucketOKMu.Lock()
defer f.bucketOKMu.Unlock()
if f.bucketOK {
return nil
}
_, err := f.svc.Buckets.Get(f.bucket).Do()
if err == nil {
// Bucket already exists
f.bucketOK = true
return nil
} else if gErr, ok := err.(*googleapi.Error); ok {
if gErr.Code != http.StatusNotFound {
return errors.Wrap(err, "failed to get bucket")
}
} else {
return errors.Wrap(err, "failed to get bucket")
}
if f.projectNumber == "" {
return errors.New("can't make bucket without project number")
}
bucket := storage.Bucket{
Name: f.bucket,
Location: f.location,
StorageClass: f.storageClass,
}
_, err = f.svc.Buckets.Insert(f.projectNumber, &bucket).PredefinedAcl(f.bucketACL).Do()
if err == nil {
f.bucketOK = true
}
return err
}
// Rmdir deletes the bucket if the fs is at the root
//
// Returns an error if it isn't empty: Error 409: The bucket you tried
// to delete was not empty.
func (f *Fs) Rmdir(dir string) error {
f.bucketOKMu.Lock()
defer f.bucketOKMu.Unlock()
if f.root != "" || dir != "" {
return nil
}
err := f.svc.Buckets.Delete(f.bucket).Do()
if err == nil {
f.bucketOK = false
}
return err
}
// Precision returns the precision
func (f *Fs) Precision() time.Duration {
return time.Nanosecond
}
// Copy src to this remote using server side copy operations.
//
// This is stored with the remote path given
//
// It returns the destination Object and a possible error
//
// Will only be called if src.Fs().Name() == f.Name()
//
// If it isn't possible then return fs.ErrorCantCopy
func (f *Fs) Copy(src fs.Object, remote string) (fs.Object, error) {
err := f.Mkdir("")
if err != nil {
return nil, err
}
srcObj, ok := src.(*Object)
if !ok {
fs.Debugf(src, "Can't copy - not same remote type")
return nil, fs.ErrorCantCopy
}
// Temporary Object under construction
dstObj := &Object{
fs: f,
remote: remote,
}
srcBucket := srcObj.fs.bucket
srcObject := srcObj.fs.root + srcObj.remote
dstBucket := f.bucket
dstObject := f.root + remote
newObject, err := f.svc.Objects.Copy(srcBucket, srcObject, dstBucket, dstObject, nil).Do()
if err != nil {
return nil, err
}
// Set the metadata for the new object while we have it
dstObj.setMetaData(newObject)
return dstObj, nil
}
// Hashes returns the supported hash sets.
func (f *Fs) Hashes() hash.Set {
return hash.Set(hash.MD5)
}
// ------------------------------------------------------------
// Fs returns the parent Fs
func (o *Object) Fs() fs.Info {
return o.fs
}
// Return a string version
func (o *Object) String() string {
if o == nil {
return "<nil>"
}
return o.remote
}
// Remote returns the remote path
func (o *Object) Remote() string {
return o.remote
}
// Hash returns the Md5sum of an object returning a lowercase hex string
func (o *Object) Hash(t hash.Type) (string, error) {
if t != hash.MD5 {
return "", hash.ErrUnsupported
}
return o.md5sum, nil
}
// Size returns the size of an object in bytes
func (o *Object) Size() int64 {
return o.bytes
}
// setMetaData sets the fs data from a storage.Object
func (o *Object) setMetaData(info *storage.Object) {
o.url = info.MediaLink
o.bytes = int64(info.Size)
o.mimeType = info.ContentType
// Read md5sum
md5sumData, err := base64.StdEncoding.DecodeString(info.Md5Hash)
if err != nil {
fs.Logf(o, "Bad MD5 decode: %v", err)
} else {
o.md5sum = hex.EncodeToString(md5sumData)
}
// read mtime out of metadata if available
mtimeString, ok := info.Metadata[metaMtime]
if ok {
modTime, err := time.Parse(timeFormatIn, mtimeString)
if err == nil {
o.modTime = modTime
return
}
fs.Debugf(o, "Failed to read mtime from metadata: %s", err)
}
// Fallback to the Updated time
modTime, err := time.Parse(timeFormatIn, info.Updated)
if err != nil {
fs.Logf(o, "Bad time decode: %v", err)
} else {
o.modTime = modTime
}
}
// readMetaData gets the metadata if it hasn't already been fetched
//
// it also sets the info
func (o *Object) readMetaData() (err error) {
if !o.modTime.IsZero() {
return nil
}
object, err := o.fs.svc.Objects.Get(o.fs.bucket, o.fs.root+o.remote).Do()
if err != nil {
if gErr, ok := err.(*googleapi.Error); ok {
if gErr.Code == http.StatusNotFound {
return fs.ErrorObjectNotFound
}
}
return err
}
o.setMetaData(object)
return nil
}
// ModTime returns the modification time of the object
//
// It attempts to read the objects mtime and if that isn't present the
// LastModified returned in the http headers
func (o *Object) ModTime() time.Time {
err := o.readMetaData()
if err != nil {
// fs.Logf(o, "Failed to read metadata: %v", err)
return time.Now()
}
return o.modTime
}
// Returns metadata for an object
func metadataFromModTime(modTime time.Time) map[string]string {
metadata := make(map[string]string, 1)
metadata[metaMtime] = modTime.Format(timeFormatOut)
return metadata
}
// SetModTime sets the modification time of the local fs object
func (o *Object) SetModTime(modTime time.Time) error {
// This only adds metadata so will perserve other metadata
object := storage.Object{
Bucket: o.fs.bucket,
Name: o.fs.root + o.remote,
Metadata: metadataFromModTime(modTime),
}
newObject, err := o.fs.svc.Objects.Patch(o.fs.bucket, o.fs.root+o.remote, &object).Do()
if err != nil {
return err
}
o.setMetaData(newObject)
return nil
}
// Storable returns a boolean as to whether this object is storable
func (o *Object) Storable() bool {
return true
}
// Open an object for read
func (o *Object) Open(options ...fs.OpenOption) (in io.ReadCloser, err error) {
req, err := http.NewRequest("GET", o.url, nil)
if err != nil {
return nil, err
}
fs.OpenOptionAddHTTPHeaders(req.Header, options)
res, err := o.fs.client.Do(req)
if err != nil {
return nil, err
}
_, isRanging := req.Header["Range"]
if !(res.StatusCode == http.StatusOK || (isRanging && res.StatusCode == http.StatusPartialContent)) {
_ = res.Body.Close() // ignore error
return nil, errors.Errorf("bad response: %d: %s", res.StatusCode, res.Status)
}
return res.Body, nil
}
// Update the object with the contents of the io.Reader, modTime and size
//
// The new object may have been created if an error is returned
func (o *Object) Update(in io.Reader, src fs.ObjectInfo, options ...fs.OpenOption) error {
err := o.fs.Mkdir("")
if err != nil {
return err
}
modTime := src.ModTime()
object := storage.Object{
Bucket: o.fs.bucket,
Name: o.fs.root + o.remote,
ContentType: fs.MimeType(src),
Updated: modTime.Format(timeFormatOut), // Doesn't get set
Metadata: metadataFromModTime(modTime),
}
newObject, err := o.fs.svc.Objects.Insert(o.fs.bucket, &object).Media(in, googleapi.ContentType("")).Name(object.Name).PredefinedAcl(o.fs.objectACL).Do()
if err != nil {
return err
}
// Set the metadata for the new object while we have it
o.setMetaData(newObject)
return nil
}
// Remove an object
func (o *Object) Remove() error {
return o.fs.svc.Objects.Delete(o.fs.bucket, o.fs.root+o.remote).Do()
}
// MimeType of an Object if known, "" otherwise
func (o *Object) MimeType() string {
return o.mimeType
}
// Check the interfaces are satisfied
var (
_ fs.Fs = &Fs{}
_ fs.Copier = &Fs{}
_ fs.PutStreamer = &Fs{}
_ fs.ListRer = &Fs{}
_ fs.Object = &Object{}
_ fs.MimeTyper = &Object{}
)