Files
sftpgo/vfs/s3fs.go
Nicola Murino 2a9f7db1e2 Cloud FS: don't propagate the error if removing a folder returns not found
for Cloud FS the folders are virtual and they, generally, disappear when the
last file is removed.

This fix doesn't work for FTP protocol for now.

Fixes #149
2020-07-31 19:24:57 +02:00

533 lines
15 KiB
Go

// +build !nos3
package vfs
import (
"context"
"errors"
"fmt"
"os"
"path"
"path/filepath"
"strings"
"time"
"github.com/aws/aws-sdk-go/aws"
"github.com/aws/aws-sdk-go/aws/awserr"
"github.com/aws/aws-sdk-go/aws/credentials"
"github.com/aws/aws-sdk-go/aws/session"
"github.com/aws/aws-sdk-go/service/s3"
"github.com/aws/aws-sdk-go/service/s3/s3manager"
"github.com/eikenb/pipeat"
"github.com/drakkan/sftpgo/logger"
"github.com/drakkan/sftpgo/metrics"
"github.com/drakkan/sftpgo/utils"
"github.com/drakkan/sftpgo/version"
)
// S3Fs is a Fs implementation for Amazon S3 compatible object storage.
type S3Fs struct {
connectionID string
localTempDir string
config S3FsConfig
svc *s3.S3
ctxTimeout time.Duration
ctxLongTimeout time.Duration
}
func init() {
version.AddFeature("+s3")
}
// NewS3Fs returns an S3Fs object that allows to interact with an s3 compatible
// object storage
func NewS3Fs(connectionID, localTempDir string, config S3FsConfig) (Fs, error) {
fs := S3Fs{
connectionID: connectionID,
localTempDir: localTempDir,
config: config,
ctxTimeout: 30 * time.Second,
ctxLongTimeout: 300 * time.Second,
}
if err := ValidateS3FsConfig(&fs.config); err != nil {
return fs, err
}
awsConfig := aws.NewConfig()
if len(fs.config.Region) > 0 {
awsConfig.WithRegion(fs.config.Region)
}
if len(fs.config.AccessSecret) > 0 {
accessSecret, err := utils.DecryptData(fs.config.AccessSecret)
if err != nil {
return fs, err
}
fs.config.AccessSecret = accessSecret
awsConfig.Credentials = credentials.NewStaticCredentials(fs.config.AccessKey, fs.config.AccessSecret, "")
}
if len(fs.config.Endpoint) > 0 {
awsConfig.Endpoint = aws.String(fs.config.Endpoint)
awsConfig.S3ForcePathStyle = aws.Bool(true)
}
if fs.config.UploadPartSize == 0 {
fs.config.UploadPartSize = s3manager.DefaultUploadPartSize
} else {
fs.config.UploadPartSize *= 1024 * 1024
}
if fs.config.UploadConcurrency == 0 {
fs.config.UploadConcurrency = 2
}
sessOpts := session.Options{
Config: *awsConfig,
SharedConfigState: session.SharedConfigEnable,
}
sess, err := session.NewSessionWithOptions(sessOpts)
if err != nil {
return fs, err
}
fs.svc = s3.New(sess)
return fs, nil
}
// Name returns the name for the Fs implementation
func (fs S3Fs) Name() string {
return fmt.Sprintf("S3Fs bucket: %#v", fs.config.Bucket)
}
// ConnectionID returns the SSH connection ID associated to this Fs implementation
func (fs S3Fs) ConnectionID() string {
return fs.connectionID
}
// Stat returns a FileInfo describing the named file
func (fs S3Fs) Stat(name string) (os.FileInfo, error) {
var result FileInfo
if name == "/" || name == "." {
err := fs.checkIfBucketExists()
if err != nil {
return result, err
}
return NewFileInfo(name, true, 0, time.Time{}), nil
}
if "/"+fs.config.KeyPrefix == name+"/" {
return NewFileInfo(name, true, 0, time.Time{}), nil
}
prefix := path.Dir(name)
if prefix == "/" || prefix == "." {
prefix = ""
} else {
prefix = strings.TrimPrefix(prefix, "/")
if !strings.HasSuffix(prefix, "/") {
prefix += "/"
}
}
ctx, cancelFn := context.WithDeadline(context.Background(), time.Now().Add(fs.ctxTimeout))
defer cancelFn()
err := fs.svc.ListObjectsV2PagesWithContext(ctx, &s3.ListObjectsV2Input{
Bucket: aws.String(fs.config.Bucket),
Prefix: aws.String(prefix),
Delimiter: aws.String("/"),
}, func(page *s3.ListObjectsV2Output, lastPage bool) bool {
for _, p := range page.CommonPrefixes {
if fs.isEqual(p.Prefix, name) {
result = NewFileInfo(name, true, 0, time.Time{})
return false
}
}
for _, fileObject := range page.Contents {
if fs.isEqual(fileObject.Key, name) {
objectSize := *fileObject.Size
objectModTime := *fileObject.LastModified
isDir := strings.HasSuffix(*fileObject.Key, "/")
result = NewFileInfo(name, isDir, objectSize, objectModTime)
return false
}
}
return true
})
metrics.S3ListObjectsCompleted(err)
if err == nil && len(result.Name()) == 0 {
err = errors.New("404 no such file or directory")
}
return result, err
}
// Lstat returns a FileInfo describing the named file
func (fs S3Fs) Lstat(name string) (os.FileInfo, error) {
return fs.Stat(name)
}
// Open opens the named file for reading
func (fs S3Fs) Open(name string) (*os.File, *pipeat.PipeReaderAt, func(), error) {
r, w, err := pipeat.AsyncWriterPipeInDir(fs.localTempDir)
if err != nil {
return nil, nil, nil, err
}
ctx, cancelFn := context.WithCancel(context.Background())
downloader := s3manager.NewDownloaderWithClient(fs.svc)
go func() {
defer cancelFn()
key := name
n, err := downloader.DownloadWithContext(ctx, w, &s3.GetObjectInput{
Bucket: aws.String(fs.config.Bucket),
Key: aws.String(key),
})
w.CloseWithError(err) //nolint:errcheck // the returned error is always null
fsLog(fs, logger.LevelDebug, "download completed, path: %#v size: %v, err: %v", name, n, err)
metrics.S3TransferCompleted(n, 1, err)
}()
return nil, r, cancelFn, nil
}
// Create creates or opens the named file for writing
func (fs S3Fs) Create(name string, flag int) (*os.File, *PipeWriter, func(), error) {
r, w, err := pipeat.PipeInDir(fs.localTempDir)
if err != nil {
return nil, nil, nil, err
}
p := NewPipeWriter(w)
ctx, cancelFn := context.WithCancel(context.Background())
uploader := s3manager.NewUploaderWithClient(fs.svc)
go func() {
defer cancelFn()
key := name
response, err := uploader.UploadWithContext(ctx, &s3manager.UploadInput{
Bucket: aws.String(fs.config.Bucket),
Key: aws.String(key),
Body: r,
StorageClass: utils.NilIfEmpty(fs.config.StorageClass),
}, func(u *s3manager.Uploader) {
u.Concurrency = fs.config.UploadConcurrency
u.PartSize = fs.config.UploadPartSize
})
r.CloseWithError(err) //nolint:errcheck // the returned error is always null
p.Done(err)
fsLog(fs, logger.LevelDebug, "upload completed, path: %#v, response: %v, readed bytes: %v, err: %+v",
name, response, r.GetReadedBytes(), err)
metrics.S3TransferCompleted(r.GetReadedBytes(), 0, err)
}()
return nil, p, cancelFn, nil
}
// Rename renames (moves) source to target.
// We don't support renaming non empty directories since we should
// rename all the contents too and this could take long time: think
// about directories with thousands of files, for each file we should
// execute a CopyObject call.
// TODO: rename does not work for files bigger than 5GB, implement
// multipart copy or wait for this pull request to be merged:
//
// https://github.com/aws/aws-sdk-go/pull/2653
//
func (fs S3Fs) Rename(source, target string) error {
if source == target {
return nil
}
fi, err := fs.Stat(source)
if err != nil {
return err
}
copySource := fs.Join(fs.config.Bucket, source)
if fi.IsDir() {
contents, err := fs.ReadDir(source)
if err != nil {
return err
}
if len(contents) > 0 {
return fmt.Errorf("Cannot rename non empty directory: %#v", source)
}
if !strings.HasSuffix(copySource, "/") {
copySource += "/"
}
if !strings.HasSuffix(target, "/") {
target += "/"
}
}
ctx, cancelFn := context.WithDeadline(context.Background(), time.Now().Add(fs.ctxTimeout))
defer cancelFn()
_, err = fs.svc.CopyObjectWithContext(ctx, &s3.CopyObjectInput{
Bucket: aws.String(fs.config.Bucket),
CopySource: aws.String(copySource),
Key: aws.String(target),
})
metrics.S3CopyObjectCompleted(err)
if err != nil {
return err
}
return fs.Remove(source, fi.IsDir())
}
// Remove removes the named file or (empty) directory.
func (fs S3Fs) Remove(name string, isDir bool) error {
if isDir {
contents, err := fs.ReadDir(name)
if err != nil {
return err
}
if len(contents) > 0 {
return fmt.Errorf("Cannot remove non empty directory: %#v", name)
}
if !strings.HasSuffix(name, "/") {
name += "/"
}
}
ctx, cancelFn := context.WithDeadline(context.Background(), time.Now().Add(fs.ctxTimeout))
defer cancelFn()
_, err := fs.svc.DeleteObjectWithContext(ctx, &s3.DeleteObjectInput{
Bucket: aws.String(fs.config.Bucket),
Key: aws.String(name),
})
metrics.S3DeleteObjectCompleted(err)
return err
}
// Mkdir creates a new directory with the specified name and default permissions
func (fs S3Fs) Mkdir(name string) error {
_, err := fs.Stat(name)
if !fs.IsNotExist(err) {
return err
}
if !strings.HasSuffix(name, "/") {
name += "/"
}
_, w, _, err := fs.Create(name, 0)
if err != nil {
return err
}
return w.Close()
}
// Symlink creates source as a symbolic link to target.
func (S3Fs) Symlink(source, target string) error {
return errors.New("403 symlinks are not supported")
}
// Chown changes the numeric uid and gid of the named file.
// Silently ignored.
func (S3Fs) Chown(name string, uid int, gid int) error {
return nil
}
// Chmod changes the mode of the named file to mode.
// Silently ignored.
func (S3Fs) Chmod(name string, mode os.FileMode) error {
return nil
}
// Chtimes changes the access and modification times of the named file.
// Silently ignored.
func (S3Fs) Chtimes(name string, atime, mtime time.Time) error {
return errors.New("403 chtimes is not supported")
}
// ReadDir reads the directory named by dirname and returns
// a list of directory entries.
func (fs S3Fs) ReadDir(dirname string) ([]os.FileInfo, error) {
var result []os.FileInfo
// dirname must be already cleaned
prefix := ""
if dirname != "/" && dirname != "." {
prefix = strings.TrimPrefix(dirname, "/")
if !strings.HasSuffix(prefix, "/") {
prefix += "/"
}
}
ctx, cancelFn := context.WithDeadline(context.Background(), time.Now().Add(fs.ctxTimeout))
defer cancelFn()
err := fs.svc.ListObjectsV2PagesWithContext(ctx, &s3.ListObjectsV2Input{
Bucket: aws.String(fs.config.Bucket),
Prefix: aws.String(prefix),
Delimiter: aws.String("/"),
}, func(page *s3.ListObjectsV2Output, lastPage bool) bool {
for _, p := range page.CommonPrefixes {
name, isDir := fs.resolve(p.Prefix, prefix)
result = append(result, NewFileInfo(name, isDir, 0, time.Time{}))
}
for _, fileObject := range page.Contents {
objectSize := *fileObject.Size
objectModTime := *fileObject.LastModified
name, isDir := fs.resolve(fileObject.Key, prefix)
if len(name) == 0 {
continue
}
result = append(result, NewFileInfo(name, isDir, objectSize, objectModTime))
}
return true
})
metrics.S3ListObjectsCompleted(err)
return result, err
}
// IsUploadResumeSupported returns true if upload resume is supported.
// SFTP Resume is not supported on S3
func (S3Fs) IsUploadResumeSupported() bool {
return false
}
// IsAtomicUploadSupported returns true if atomic upload is supported.
// S3 uploads are already atomic, we don't need to upload to a temporary
// file
func (S3Fs) IsAtomicUploadSupported() bool {
return false
}
// IsNotExist returns a boolean indicating whether the error is known to
// report that a file or directory does not exist
func (S3Fs) IsNotExist(err error) bool {
if err == nil {
return false
}
if aerr, ok := err.(awserr.Error); ok {
if aerr.Code() == s3.ErrCodeNoSuchKey {
return true
}
if aerr.Code() == s3.ErrCodeNoSuchBucket {
return true
}
}
if multierr, ok := err.(s3manager.MultiUploadFailure); ok {
if multierr.Code() == s3.ErrCodeNoSuchKey {
return true
}
if multierr.Code() == s3.ErrCodeNoSuchBucket {
return true
}
}
return strings.Contains(err.Error(), "404")
}
// IsPermission returns a boolean indicating whether the error is known to
// report that permission is denied.
func (S3Fs) IsPermission(err error) bool {
if err == nil {
return false
}
return strings.Contains(err.Error(), "403")
}
// CheckRootPath creates the specified root directory if it does not exists
func (fs S3Fs) CheckRootPath(username string, uid int, gid int) bool {
// we need a local directory for temporary files
osFs := NewOsFs(fs.ConnectionID(), fs.localTempDir, nil)
osFs.CheckRootPath(username, uid, gid)
return fs.checkIfBucketExists() != nil
}
// ScanRootDirContents returns the number of files contained in the bucket,
// and their size
func (fs S3Fs) ScanRootDirContents() (int, int64, error) {
numFiles := 0
size := int64(0)
ctx, cancelFn := context.WithDeadline(context.Background(), time.Now().Add(fs.ctxLongTimeout))
defer cancelFn()
err := fs.svc.ListObjectsV2PagesWithContext(ctx, &s3.ListObjectsV2Input{
Bucket: aws.String(fs.config.Bucket),
Prefix: aws.String(fs.config.KeyPrefix),
}, func(page *s3.ListObjectsV2Output, lastPage bool) bool {
for _, fileObject := range page.Contents {
numFiles++
size += *fileObject.Size
}
return true
})
metrics.S3ListObjectsCompleted(err)
return numFiles, size, err
}
// GetDirSize returns the number of files and the size for a folder
// including any subfolders
func (S3Fs) GetDirSize(dirname string) (int, int64, error) {
return 0, 0, errUnsupported
}
// GetAtomicUploadPath returns the path to use for an atomic upload.
// S3 uploads are already atomic, we never call this method for S3
func (S3Fs) GetAtomicUploadPath(name string) string {
return ""
}
// GetRelativePath returns the path for a file relative to the user's home dir.
// This is the path as seen by SFTP users
func (fs S3Fs) GetRelativePath(name string) string {
rel := path.Clean(name)
if rel == "." {
rel = ""
}
if !strings.HasPrefix(rel, "/") {
return "/" + rel
}
if len(fs.config.KeyPrefix) > 0 {
if !strings.HasPrefix(rel, "/"+fs.config.KeyPrefix) {
rel = "/"
}
rel = path.Clean("/" + strings.TrimPrefix(rel, "/"+fs.config.KeyPrefix))
}
return rel
}
// Walk walks the file tree rooted at root, calling walkFn for each file or
// directory in the tree, including root
func (S3Fs) Walk(root string, walkFn filepath.WalkFunc) error {
return errUnsupported
}
// Join joins any number of path elements into a single path
func (S3Fs) Join(elem ...string) string {
return path.Join(elem...)
}
// HasVirtualFolders returns true if folders are emulated
func (S3Fs) HasVirtualFolders() bool {
return true
}
// ResolvePath returns the matching filesystem path for the specified sftp path
func (fs S3Fs) ResolvePath(sftpPath string) (string, error) {
if !path.IsAbs(sftpPath) {
sftpPath = path.Clean("/" + sftpPath)
}
return fs.Join("/", fs.config.KeyPrefix, sftpPath), nil
}
func (fs *S3Fs) resolve(name *string, prefix string) (string, bool) {
result := strings.TrimPrefix(*name, prefix)
isDir := strings.HasSuffix(result, "/")
if isDir {
result = strings.TrimSuffix(result, "/")
}
if strings.Contains(result, "/") {
i := strings.Index(result, "/")
isDir = true
result = result[:i]
}
return result, isDir
}
func (fs *S3Fs) isEqual(s3Key *string, sftpName string) bool {
if *s3Key == sftpName {
return true
}
if "/"+*s3Key == sftpName {
return true
}
if "/"+*s3Key == sftpName+"/" {
return true
}
return false
}
func (fs *S3Fs) checkIfBucketExists() error {
ctx, cancelFn := context.WithDeadline(context.Background(), time.Now().Add(fs.ctxTimeout))
defer cancelFn()
_, err := fs.svc.HeadBucketWithContext(ctx, &s3.HeadBucketInput{
Bucket: aws.String(fs.config.Bucket),
})
metrics.S3HeadBucketCompleted(err)
return err
}