/*

* Minio Cloud Storage, (C) 2016, 2017, 2018 Minio, Inc.

*

* 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 cmd

import (

"bytes"

"context"

"io"

"io/ioutil"

"net/http"

"os"

"path"

"sort"

"strings"

"sync"

"sync/atomic"

"time"

"github.com/minio/minio-go/pkg/s3utils"

"github.com/minio/minio/cmd/logger"

"github.com/minio/minio/pkg/lock"

"github.com/minio/minio/pkg/madmin"

"github.com/minio/minio/pkg/mimedb"

"github.com/minio/minio/pkg/mountinfo"

"github.com/minio/minio/pkg/policy"

)

// Default etag is used for pre-existing objects.

var defaultEtag = "00000000000000000000000000000000-1"

// FSObjects - Implements fs object layer.

type FSObjects struct {

// Disk usage metrics

totalUsed uint64 // ref: https://golang.org/pkg/sync/atomic/#pkg-note-BUG

// Path to be exported over S3 API.

fsPath string

// meta json filename, varies by fs / cache backend.

metaJSONFile string

// Unique value to be used for all

// temporary transactions.

fsUUID string

// This value shouldn't be touched, once initialized.

fsFormatRlk *lock.RLockedFile // Is a read lock on `format.json`.

// FS rw pool.

rwPool *fsIOPool

// ListObjects pool management.

listPool *treeWalkPool

diskMount bool

appendFileMap map[string]*fsAppendFile

appendFileMapMu sync.Mutex

// To manage the appendRoutine go-routines

nsMutex *nsLockMap

}

// Represents the background append file.

type fsAppendFile struct {

sync.Mutex

parts []PartInfo // List of parts appended.

filePath string // Absolute path of the file in the temp location.

}

// Initializes meta volume on all the fs path.

func initMetaVolumeFS(fsPath, fsUUID string) error {

// This happens for the first time, but keep this here since this

// is the only place where it can be made less expensive

// optimizing all other calls. Create minio meta volume,

// if it doesn't exist yet.

metaBucketPath := pathJoin(fsPath, minioMetaBucket)

if err := os.MkdirAll(metaBucketPath, 0777); err != nil {

return err

}

metaTmpPath := pathJoin(fsPath, minioMetaTmpBucket, fsUUID)

if err := os.MkdirAll(metaTmpPath, 0777); err != nil {

return err

}

metaMultipartPath := pathJoin(fsPath, minioMetaMultipartBucket)

return os.MkdirAll(metaMultipartPath, 0777)

}

// NewFSObjectLayer - initialize new fs object layer.

func NewFSObjectLayer(fsPath string) (ObjectLayer, error) {

ctx := context.Background()

if fsPath == "" {

return nil, errInvalidArgument

}

var err error

if fsPath, err = getValidPath(fsPath); err != nil {

if err == errMinDiskSize {

return nil, err

}

return nil, uiErrUnableToWriteInBackend(err)

}

// Assign a new UUID for FS minio mode. Each server instance

// gets its own UUID for temporary file transaction.

fsUUID := mustGetUUID()

// Initialize meta volume, if volume already exists ignores it.

if err = initMetaVolumeFS(fsPath, fsUUID); err != nil {

return nil, err

}

// Initialize `format.json`, this function also returns.

rlk, err := initFormatFS(ctx, fsPath)

if err != nil {

return nil, err

}

// Initialize fs objects.

fs := &FSObjects{

fsPath: fsPath,

metaJSONFile: fsMetaJSONFile,

fsUUID: fsUUID,

rwPool: &fsIOPool{

readersMap: make(map[string]*lock.RLockedFile),

},

nsMutex: newNSLock(false),

listPool: newTreeWalkPool(globalLookupTimeout),

appendFileMap: make(map[string]*fsAppendFile),

diskMount: mountinfo.IsLikelyMountPoint(fsPath),

}

// Once the filesystem has initialized hold the read lock for

// the life time of the server. This is done to ensure that under

// shared backend mode for FS, remote servers do not migrate

// or cause changes on backend format.

fs.fsFormatRlk = rlk

if !fs.diskMount {

go fs.diskUsage(GlobalServiceDoneCh)

}

go fs.cleanupStaleMultipartUploads(ctx, GlobalMultipartCleanupInterval, GlobalMultipartExpiry, GlobalServiceDoneCh)

// Return successfully initialized object layer.

return fs, nil

}

// Shutdown - should be called when process shuts down.

func (fs *FSObjects) Shutdown(ctx context.Context) error {

fs.fsFormatRlk.Close()

// Cleanup and delete tmp uuid.

return fsRemoveAll(ctx, pathJoin(fs.fsPath, minioMetaTmpBucket, fs.fsUUID))

}

// diskUsage returns du information for the posix path, in a continuous routine.

func (fs *FSObjects) diskUsage(doneCh chan struct{}) {

usageFn := func(ctx context.Context, entry string) error {

if globalHTTPServer != nil {

// Wait at max 1 minute for an inprogress request

// before proceeding to count the usage.

waitCount := 60

// Any requests in progress, delay the usage.

for globalHTTPServer.GetRequestCount() > 0 && waitCount > 0 {

waitCount--

time.Sleep(1 * time.Second)

}

}

select {

case <-doneCh:

return errWalkAbort

default:

fi, err := os.Stat(entry)

if err != nil {

err = osErrToFSFileErr(err)

return err

}

atomic.AddUint64(&fs.totalUsed, uint64(fi.Size()))

}

return nil

}

// Return this routine upon errWalkAbort, continue for any other error on purpose

// so that we can start the routine freshly in another 12 hours.

if err := getDiskUsage(context.Background(), fs.fsPath, usageFn); err == errWalkAbort {

return

}

for {

select {

case <-doneCh:

return

case <-time.After(globalUsageCheckInterval):

var usage uint64

usageFn = func(ctx context.Context, entry string) error {

if globalHTTPServer != nil {

// Wait at max 1 minute for an inprogress request

// before proceeding to count the usage.

waitCount := 60

// Any requests in progress, delay the usage.

for globalHTTPServer.GetRequestCount() > 0 && waitCount > 0 {

waitCount--

time.Sleep(1 * time.Second)

}

}

fi, err := os.Stat(entry)

if err != nil {

err = osErrToFSFileErr(err)

return err

}

usage = usage + uint64(fi.Size())

return nil

}

if err := getDiskUsage(context.Background(), fs.fsPath, usageFn); err != nil {

continue

}

atomic.StoreUint64(&fs.totalUsed, usage)

}

}

}

// StorageInfo - returns underlying storage statistics.

func (fs *FSObjects) StorageInfo(ctx context.Context) StorageInfo {

di, err := getDiskInfo(fs.fsPath)

if err != nil {

return StorageInfo{}

}

used := di.Total - di.Free

if !fs.diskMount {

used = atomic.LoadUint64(&fs.totalUsed)

}

storageInfo := StorageInfo{

Used: used,

}

storageInfo.Backend.Type = BackendFS

return storageInfo

}

/// Bucket operations

// getBucketDir - will convert incoming bucket names to

// corresponding valid bucket names on the backend in a platform

// compatible way for all operating systems.

func (fs *FSObjects) getBucketDir(ctx context.Context, bucket string) (string, error) {

if bucket == "" || bucket == "." || bucket == ".." {

return "", errVolumeNotFound

}

bucketDir := pathJoin(fs.fsPath, bucket)

return bucketDir, nil

}

func (fs *FSObjects) statBucketDir(ctx context.Context, bucket string) (os.FileInfo, error) {

bucketDir, err := fs.getBucketDir(ctx, bucket)

if err != nil {

return nil, err

}

st, err := fsStatVolume(ctx, bucketDir)

if err != nil {

return nil, err

}

return st, nil

}

// MakeBucketWithLocation - create a new bucket, returns if it

// already exists.

func (fs *FSObjects) MakeBucketWithLocation(ctx context.Context, bucket, location string) error {

bucketLock := fs.nsMutex.NewNSLock(bucket, "")

if err := bucketLock.GetLock(globalObjectTimeout); err != nil {

return err

}

defer bucketLock.Unlock()

// Verify if bucket is valid.

if s3utils.CheckValidBucketNameStrict(bucket) != nil {

return BucketNameInvalid{Bucket: bucket}

}

bucketDir, err := fs.getBucketDir(ctx, bucket)

if err != nil {

return toObjectErr(err, bucket)

}

if err = fsMkdir(ctx, bucketDir); err != nil {

return toObjectErr(err, bucket)

}

return nil

}

// GetBucketInfo - fetch bucket metadata info.

func (fs *FSObjects) GetBucketInfo(ctx context.Context, bucket string) (bi BucketInfo, e error) {

bucketLock := fs.nsMutex.NewNSLock(bucket, "")

if e := bucketLock.GetRLock(globalObjectTimeout); e != nil {

return bi, e

}

defer bucketLock.RUnlock()

st, err := fs.statBucketDir(ctx, bucket)

if err != nil {

return bi, toObjectErr(err, bucket)

}

// As os.Stat() doesn't carry other than ModTime(), use ModTime() as CreatedTime.

createdTime := st.ModTime()

return BucketInfo{

Name: bucket,

Created: createdTime,

}, nil

}

// ListBuckets - list all s3 compatible buckets (directories) at fsPath.

func (fs *FSObjects) ListBuckets(ctx context.Context) ([]BucketInfo, error) {

if err := checkPathLength(fs.fsPath); err != nil {

logger.LogIf(ctx, err)

return nil, err

}

var bucketInfos []BucketInfo

entries, err := readDir((fs.fsPath))

if err != nil {

logger.LogIf(ctx, errDiskNotFound)

return nil, toObjectErr(errDiskNotFound)

}

for _, entry := range entries {

// Ignore all reserved bucket names and invalid bucket names.

if isReservedOrInvalidBucket(entry, false) {

continue

}

var fi os.FileInfo

fi, err = fsStatVolume(ctx, pathJoin(fs.fsPath, entry))

// There seems like no practical reason to check for errors

// at this point, if there are indeed errors we can simply

// just ignore such buckets and list only those which

// return proper Stat information instead.

if err != nil {

// Ignore any errors returned here.

continue

}

bucketInfos = append(bucketInfos, BucketInfo{

Name: fi.Name(),

// As os.Stat() doesnt carry CreatedTime, use ModTime() as CreatedTime.

Created: fi.ModTime(),

})

}

// Sort bucket infos by bucket name.

sort.Sort(byBucketName(bucketInfos))

// Succes.

return bucketInfos, nil

}

// DeleteBucket - delete a bucket and all the metadata associated

// with the bucket including pending multipart, object metadata.

func (fs *FSObjects) DeleteBucket(ctx context.Context, bucket string) error {

bucketLock := fs.nsMutex.NewNSLock(bucket, "")

if err := bucketLock.GetLock(globalObjectTimeout); err != nil {

logger.LogIf(ctx, err)

return err

}

defer bucketLock.Unlock()

bucketDir, err := fs.getBucketDir(ctx, bucket)

if err != nil {

return toObjectErr(err, bucket)

}

// Attempt to delete regular bucket.

if err = fsRemoveDir(ctx, bucketDir); err != nil {

return toObjectErr(err, bucket)

}

// Cleanup all the bucket metadata.

minioMetadataBucketDir := pathJoin(fs.fsPath, minioMetaBucket, bucketMetaPrefix, bucket)

if err = fsRemoveAll(ctx, minioMetadataBucketDir); err != nil {

return toObjectErr(err, bucket)

}

// Delete all bucket metadata.

deleteBucketMetadata(ctx, bucket, fs)

return nil

}

/// Object Operations

// CopyObject - copy object source object to destination object.

// if source object and destination object are same we only

// update metadata.

func (fs *FSObjects) CopyObject(ctx context.Context, srcBucket, srcObject, dstBucket, dstObject string, srcInfo ObjectInfo, srcOpts, dstOpts ObjectOptions) (oi ObjectInfo, e error) {

cpSrcDstSame := isStringEqual(pathJoin(srcBucket, srcObject), pathJoin(dstBucket, dstObject))

if !cpSrcDstSame {

objectDWLock := fs.nsMutex.NewNSLock(dstBucket, dstObject)

if err := objectDWLock.GetLock(globalObjectTimeout); err != nil {

return oi, err

}

defer objectDWLock.Unlock()

}

if _, err := fs.statBucketDir(ctx, srcBucket); err != nil {

return oi, toObjectErr(err, srcBucket)

}

if cpSrcDstSame && srcInfo.metadataOnly {

fsMetaPath := pathJoin(fs.fsPath, minioMetaBucket, bucketMetaPrefix, srcBucket, srcObject, fs.metaJSONFile)

wlk, err := fs.rwPool.Write(fsMetaPath)

if err != nil {

logger.LogIf(ctx, err)

return oi, toObjectErr(err, srcBucket, srcObject)

}

// This close will allow for locks to be synchronized on `fs.json`.

defer wlk.Close()

// Save objects' metadata in `fs.json`.

fsMeta := newFSMetaV1()

if _, err = fsMeta.ReadFrom(ctx, wlk); err != nil && err != io.EOF {

return oi, toObjectErr(err, srcBucket, srcObject)

}

fsMeta.Meta = srcInfo.UserDefined

fsMeta.Meta["etag"] = srcInfo.ETag

if _, err = fsMeta.WriteTo(wlk); err != nil {

return oi, toObjectErr(err, srcBucket, srcObject)

}

// Stat the file to get file size.

fi, err := fsStatFile(ctx, pathJoin(fs.fsPath, srcBucket, srcObject))

if err != nil {

return oi, toObjectErr(err, srcBucket, srcObject)

}

// Return the new object info.

return fsMeta.ToObjectInfo(srcBucket, srcObject, fi), nil

}

objInfo, err := fs.putObject(ctx, dstBucket, dstObject, srcInfo.PutObjReader, ObjectOptions{ServerSideEncryption: dstOpts.ServerSideEncryption, UserDefined: srcInfo.UserDefined})

if err != nil {

return oi, toObjectErr(err, dstBucket, dstObject)

}

return objInfo, nil

}

// GetObjectNInfo - returns object info and a reader for object

// content.

func (fs *FSObjects) GetObjectNInfo(ctx context.Context, bucket, object string, rs *HTTPRangeSpec, h http.Header, lockType LockType, opts ObjectOptions) (gr *GetObjectReader, err error) {

if err = checkGetObjArgs(ctx, bucket, object); err != nil {

return nil, err

}

if _, err = fs.statBucketDir(ctx, bucket); err != nil {

return nil, toObjectErr(err, bucket)

}

var nsUnlocker = func() {}

if lockType != noLock {

// Lock the object before reading.

lock := fs.nsMutex.NewNSLock(bucket, object)

switch lockType {

case writeLock:

if err = lock.GetLock(globalObjectTimeout); err != nil {

logger.LogIf(ctx, err)

return nil, err

}

nsUnlocker = lock.Unlock

case readLock:

if err = lock.GetRLock(globalObjectTimeout); err != nil {

logger.LogIf(ctx, err)

return nil, err

}

nsUnlocker = lock.RUnlock

}

}

// Otherwise we get the object info

var objInfo ObjectInfo

if objInfo, err = fs.getObjectInfo(ctx, bucket, object); err != nil {

nsUnlocker()

return nil, toObjectErr(err, bucket, object)

}

// For a directory, we need to send an reader that returns no bytes.

if hasSuffix(object, slashSeparator) {

// The lock taken above is released when

// objReader.Close() is called by the caller.

return NewGetObjectReaderFromReader(bytes.NewBuffer(nil), objInfo, opts.CheckCopyPrecondFn, nsUnlocker)

}

// Take a rwPool lock for NFS gateway type deployment

rwPoolUnlocker := func() {}

if bucket != minioMetaBucket && lockType != noLock {

fsMetaPath := pathJoin(fs.fsPath, minioMetaBucket, bucketMetaPrefix, bucket, object, fs.metaJSONFile)

_, err = fs.rwPool.Open(fsMetaPath)

if err != nil && err != errFileNotFound {

logger.LogIf(ctx, err)

nsUnlocker()

return nil, toObjectErr(err, bucket, object)

}

// Need to clean up lock after getObject is

// completed.

rwPoolUnlocker = func() { fs.rwPool.Close(fsMetaPath) }

}

objReaderFn, off, length, rErr := NewGetObjectReader(rs, objInfo, opts.CheckCopyPrecondFn, nsUnlocker, rwPoolUnlocker)

if rErr != nil {

return nil, rErr

}

// Read the object, doesn't exist returns an s3 compatible error.

fsObjPath := pathJoin(fs.fsPath, bucket, object)

readCloser, size, err := fsOpenFile(ctx, fsObjPath, off)

if err != nil {

rwPoolUnlocker()

nsUnlocker()

return nil, toObjectErr(err, bucket, object)

}

reader := io.LimitReader(readCloser, length)

closeFn := func() {

readCloser.Close()

}

// Check if range is valid

if off > size || off+length > size {

err = InvalidRange{off, length, size}

logger.LogIf(ctx, err)

closeFn()

rwPoolUnlocker()

nsUnlocker()

return nil, err

}

return objReaderFn(reader, h, opts.CheckCopyPrecondFn, closeFn)

}

// GetObject - reads an object from the disk.

// Supports additional parameters like offset and length

// which are synonymous with HTTP Range requests.

//

// startOffset indicates the starting read location of the object.

// length indicates the total length of the object.

func (fs *FSObjects) GetObject(ctx context.Context, bucket, object string, offset int64, length int64, writer io.Writer, etag string, opts ObjectOptions) (err error) {

if err = checkGetObjArgs(ctx, bucket, object); err != nil {

return err

}

// Lock the object before reading.

objectLock := fs.nsMutex.NewNSLock(bucket, object)

if err := objectLock.GetRLock(globalObjectTimeout); err != nil {

logger.LogIf(ctx, err)

return err

}

defer objectLock.RUnlock()

return fs.getObject(ctx, bucket, object, offset, length, writer, etag, true)

}

// getObject - wrapper for GetObject

func (fs *FSObjects) getObject(ctx context.Context, bucket, object string, offset int64, length int64, writer io.Writer, etag string, lock bool) (err error) {

if _, err = fs.statBucketDir(ctx, bucket); err != nil {

return toObjectErr(err, bucket)

}

// Offset cannot be negative.

if offset < 0 {

logger.LogIf(ctx, errUnexpected)

return toObjectErr(errUnexpected, bucket, object)

}

// Writer cannot be nil.

if writer == nil {

logger.LogIf(ctx, errUnexpected)

return toObjectErr(errUnexpected, bucket, object)

}

// If its a directory request, we return an empty body.

if hasSuffix(object, slashSeparator) {

_, err = writer.Write([]byte(""))

logger.LogIf(ctx, err)

return toObjectErr(err, bucket, object)

}

if bucket != minioMetaBucket {

fsMetaPath := pathJoin(fs.fsPath, minioMetaBucket, bucketMetaPrefix, bucket, object, fs.metaJSONFile)

if lock {

_, err = fs.rwPool.Open(fsMetaPath)

if err != nil && err != errFileNotFound {

logger.LogIf(ctx, err)

return toObjectErr(err, bucket, object)

}

defer fs.rwPool.Close(fsMetaPath)

}

}

if etag != "" && etag != defaultEtag {

objEtag, perr := fs.getObjectETag(ctx, bucket, object, lock)

if perr != nil {

return toObjectErr(perr, bucket, object)

}

if objEtag != etag {

logger.LogIf(ctx, InvalidETag{})

return toObjectErr(InvalidETag{}, bucket, object)

}

}

// Read the object, doesn't exist returns an s3 compatible error.

fsObjPath := pathJoin(fs.fsPath, bucket, object)

reader, size, err := fsOpenFile(ctx, fsObjPath, offset)

if err != nil {

return toObjectErr(err, bucket, object)

}

defer reader.Close()

bufSize := int64(readSizeV1)

if length > 0 && bufSize > length {

bufSize = length

}

// For negative length we read everything.

if length < 0 {

length = size - offset

}

// Reply back invalid range if the input offset and length fall out of range.

if offset > size || offset+length > size {

err = InvalidRange{offset, length, size}

logger.LogIf(ctx, err)

return err

}

// Allocate a staging buffer.

buf := make([]byte, int(bufSize))

_, err = io.CopyBuffer(writer, io.LimitReader(reader, length), buf)

// The writer will be closed incase of range queries, which will emit ErrClosedPipe.

if err == io.ErrClosedPipe {

err = nil

}

return toObjectErr(err, bucket, object)

}

// Create a new fs.json file, if the existing one is corrupt. Should happen very rarely.

func (fs *FSObjects) createFsJSON(object, fsMetaPath string) error {

fsMeta := newFSMetaV1()

fsMeta.Meta = make(map[string]string)

fsMeta.Meta["etag"] = GenETag()

contentType := mimedb.TypeByExtension(path.Ext(object))

fsMeta.Meta["content-type"] = contentType

wlk, werr := fs.rwPool.Create(fsMetaPath)

if werr == nil {

_, err := fsMeta.WriteTo(wlk)

wlk.Close()

return err

}

return werr

}

// Used to return default etag values when a pre-existing object's meta data is queried.

func (fs *FSObjects) defaultFsJSON(object string) fsMetaV1 {

fsMeta := newFSMetaV1()

fsMeta.Meta = make(map[string]string)

fsMeta.Meta["etag"] = defaultEtag

contentType := mimedb.TypeByExtension(path.Ext(object))

fsMeta.Meta["content-type"] = contentType

return fsMeta

}

// getObjectInfo - wrapper for reading object metadata and constructs ObjectInfo.

func (fs *FSObjects) getObjectInfo(ctx context.Context, bucket, object string) (oi ObjectInfo, e error) {

fsMeta := fsMetaV1{}

if hasSuffix(object, slashSeparator) {

// Since we support PUT of a "directory" object, we allow HEAD.

if !fsIsDir(ctx, pathJoin(fs.fsPath, bucket, object)) {

return oi, errFileNotFound

}

fi, err := fsStatDir(ctx, pathJoin(fs.fsPath, bucket, object))

if err != nil {

return oi, err

}

return fsMeta.ToObjectInfo(bucket, object, fi), nil

}

fsMetaPath := pathJoin(fs.fsPath, minioMetaBucket, bucketMetaPrefix, bucket, object, fs.metaJSONFile)

// Read `fs.json` to perhaps contend with

// parallel Put() operations.

rlk, err := fs.rwPool.Open(fsMetaPath)

if err == nil {

// Read from fs metadata only if it exists.

_, rerr := fsMeta.ReadFrom(ctx, rlk.LockedFile)

fs.rwPool.Close(fsMetaPath)

if rerr != nil {

if rerr != io.EOF {

return oi, rerr

}

// Set Default ETag, if fs.json is empty

fsMeta = fs.defaultFsJSON(object)

}

}

// Return a default etag and content-type based on the object's extension.

if err == errFileNotFound {

fsMeta = fs.defaultFsJSON(object)

}

// Ignore if `fs.json` is not available, this is true for pre-existing data.

if err != nil && err != errFileNotFound {

logger.LogIf(ctx, err)

return oi, err

}

// Stat the file to get file size.

fi, err := fsStatFile(ctx, pathJoin(fs.fsPath, bucket, object))

if err != nil {

return oi, err

}

return fsMeta.ToObjectInfo(bucket, object, fi), nil

}

// getObjectInfoWithLock - reads object metadata and replies back ObjectInfo.

func (fs *FSObjects) getObjectInfoWithLock(ctx context.Context, bucket, object string) (oi ObjectInfo, e error) {

// Lock the object before reading.

objectLock := fs.nsMutex.NewNSLock(bucket, object)

if err := objectLock.GetRLock(globalObjectTimeout); err != nil {

return oi, err

}

defer objectLock.RUnlock()

if err := checkGetObjArgs(ctx, bucket, object); err != nil {

return oi, err

}

if _, err := fs.statBucketDir(ctx, bucket); err != nil {

return oi, err

}

if strings.HasSuffix(object, slashSeparator) && !fs.isObjectDir(bucket, object) {

return oi, errFileNotFound

}

return fs.getObjectInfo(ctx, bucket, object)

}

// GetObjectInfo - reads object metadata and replies back ObjectInfo.

func (fs *FSObjects) GetObjectInfo(ctx context.Context, bucket, object string, opts ObjectOptions) (oi ObjectInfo, e error) {

oi, err := fs.getObjectInfoWithLock(ctx, bucket, object)

if err == errCorruptedFormat || err == io.EOF {

objectLock := fs.nsMutex.NewNSLock(bucket, object)

if err = objectLock.GetLock(globalObjectTimeout); err != nil {

return oi, toObjectErr(err, bucket, object)

}

fsMetaPath := pathJoin(fs.fsPath, minioMetaBucket, bucketMetaPrefix, bucket, object, fs.metaJSONFile)

err = fs.createFsJSON(object, fsMetaPath)

objectLock.Unlock()

if err != nil {

return oi, toObjectErr(err, bucket, object)

}

oi, err = fs.getObjectInfoWithLock(ctx, bucket, object)

}

return oi, toObjectErr(err, bucket, object)

}

// This function does the following check, suppose

// object is "a/b/c/d", stat makes sure that objects ""a/b/c""

// "a/b" and "a" do not exist.

func (fs *FSObjects) parentDirIsObject(ctx context.Context, bucket, parent string) bool {

var isParentDirObject func(string) bool

isParentDirObject = func(p string) bool {

if p == "." || p == "/" {

return false

}

if fsIsFile(ctx, pathJoin(fs.fsPath, bucket, p)) {

// If there is already a file at prefix "p", return true.

return true

}

// Check if there is a file as one of the parent paths.

return isParentDirObject(path.Dir(p))

}

return isParentDirObject(parent)

}

// PutObject - creates an object upon reading from the input stream

// until EOF, writes data directly to configured filesystem path.

// Additionally writes `fs.json` which carries the necessary metadata

// for future object operations.

func (fs *FSObjects) PutObject(ctx context.Context, bucket string, object string, r *PutObjReader, opts ObjectOptions) (objInfo ObjectInfo, retErr error) {

if err := checkPutObjectArgs(ctx, bucket, object, fs, r.Size()); err != nil {

return ObjectInfo{}, err

}

// Lock the object.

objectLock := fs.nsMutex.NewNSLock(bucket, object)

if err := objectLock.GetLock(globalObjectTimeout); err != nil {

logger.LogIf(ctx, err)

return objInfo, err

}

defer objectLock.Unlock()

return fs.putObject(ctx, bucket, object, r, opts)

}

// putObject - wrapper for PutObject

func (fs *FSObjects) putObject(ctx context.Context, bucket string, object string, r *PutObjReader, opts ObjectOptions) (objInfo ObjectInfo, retErr error) {

data := r.Reader

// No metadata is set, allocate a new one.

meta := make(map[string]string)

for k, v := range opts.UserDefined {

meta[k] = v

}

var err error

// Validate if bucket name is valid and exists.

if _, err = fs.statBucketDir(ctx, bucket); err != nil {

return ObjectInfo{}, toObjectErr(err, bucket)

}

fsMeta := newFSMetaV1()

fsMeta.Meta = meta

// This is a special case with size as '0' and object ends

// with a slash separator, we treat it like a valid operation

// and return success.

if isObjectDir(object, data.Size()) {

// Check if an object is present as one of the parent dir.

if fs.parentDirIsObject(ctx, bucket, path.Dir(object)) {

logger.LogIf(ctx, errFileAccessDenied)

return ObjectInfo{}, toObjectErr(errFileAccessDenied, bucket, object)

}

if err = mkdirAll(pathJoin(fs.fsPath, bucket, object), 0777); err != nil {

logger.LogIf(ctx, err)

return ObjectInfo{}, toObjectErr(err, bucket, object)

}

var fi os.FileInfo

if fi, err = fsStatDir(ctx, pathJoin(fs.fsPath, bucket, object)); err != nil {

return ObjectInfo{}, toObjectErr(err, bucket, object)

}

return fsMeta.ToObjectInfo(bucket, object, fi), nil

}

if err = checkPutObjectArgs(ctx, bucket, object, fs, data.Size()); err != nil {

return ObjectInfo{}, err

}

// Check if an object is present as one of the parent dir.

if fs.parentDirIsObject(ctx, bucket, path.Dir(object)) {

logger.LogIf(ctx, errFileAccessDenied)

return ObjectInfo{}, toObjectErr(errFileAccessDenied, bucket, object)

}

// Validate input data size and it can never be less than zero.

if data.Size() < -1 {

logger.LogIf(ctx, errInvalidArgument)

return ObjectInfo{}, errInvalidArgument

}

var wlk *lock.LockedFile

if bucket != minioMetaBucket {

bucketMetaDir := pathJoin(fs.fsPath, minioMetaBucket, bucketMetaPrefix)

fsMetaPath := pathJoin(bucketMetaDir, bucket, object, fs.metaJSONFile)

wlk, err = fs.rwPool.Create(fsMetaPath)

if err != nil {

logger.LogIf(ctx, err)

return ObjectInfo{}, toObjectErr(err, bucket, object)

}

// This close will allow for locks to be synchronized on `fs.json`.

defer wlk.Close()

defer func() {

// Remove meta file when PutObject encounters any error

if retErr != nil {

tmpDir := pathJoin(fs.fsPath, minioMetaTmpBucket, fs.fsUUID)

fsRemoveMeta(ctx, bucketMetaDir, fsMetaPath, tmpDir)

}

}()

}

// Uploaded object will first be written to the temporary location which will eventually

// be renamed to the actual location. It is first written to the temporary location

// so that cleaning it up will be easy if the server goes down.

tempObj := mustGetUUID()

// Allocate a buffer to Read() from request body

bufSize := int64(readSizeV1)

if size := data.Size(); size > 0 && bufSize > size {

bufSize = size

}

buf := make([]byte, int(bufSize))

fsTmpObjPath := pathJoin(fs.fsPath, minioMetaTmpBucket, fs.fsUUID, tempObj)

bytesWritten, err := fsCreateFile(ctx, fsTmpObjPath, data, buf, data.Size())

if err != nil {

fsRemoveFile(ctx, fsTmpObjPath)

return ObjectInfo{}, toObjectErr(err, bucket, object)

}

fsMeta.Meta["etag"] = r.MD5CurrentHexString()

// Should return IncompleteBody{} error when reader has fewer

// bytes than specified in request header.

if bytesWritten < data.Size() {

fsRemoveFile(ctx, fsTmpObjPath)

return ObjectInfo{}, IncompleteBody{}

}

// Delete the temporary object in the case of a

// failure. If PutObject succeeds, then there would be

// nothing to delete.

defer fsRemoveFile(ctx, fsTmpObjPath)

// Entire object was written to the temp location, now it's safe to rename it to the actual location.

fsNSObjPath := pathJoin(fs.fsPath, bucket, object)

// Deny if WORM is enabled

if globalWORMEnabled {

if _, err = fsStatFile(ctx, fsNSObjPath); err == nil {

return ObjectInfo{}, ObjectAlreadyExists{Bucket: bucket, Object: object}

}

}

if err = fsRenameFile(ctx, fsTmpObjPath, fsNSObjPath); err != nil {

return ObjectInfo{}, toObjectErr(err, bucket, object)

}

if bucket != minioMetaBucket {

// Write FS metadata after a successful namespace operation.

if _, err = fsMeta.WriteTo(wlk); err != nil {

return ObjectInfo{}, toObjectErr(err, bucket, object)

}

}

// Stat the file to fetch timestamp, size.

fi, err := fsStatFile(ctx, pathJoin(fs.fsPath, bucket, object))

if err != nil {

return ObjectInfo{}, toObjectErr(err, bucket, object)

}

// Success.

return fsMeta.ToObjectInfo(bucket, object, fi), nil

}

// DeleteObject - deletes an object from a bucket, this operation is destructive

// and there are no rollbacks supported.

func (fs *FSObjects) DeleteObject(ctx context.Context, bucket, object string) error {

// Acquire a write lock before deleting the object.

objectLock := fs.nsMutex.NewNSLock(bucket, object)

if err := objectLock.GetLock(globalOperationTimeout); err != nil {

return err

}

defer objectLock.Unlock()

if err := checkDelObjArgs(ctx, bucket, object); err != nil {

return err

}

if _, err := fs.statBucketDir(ctx, bucket); err != nil {

return toObjectErr(err, bucket)

}

minioMetaBucketDir := pathJoin(fs.fsPath, minioMetaBucket)

fsMetaPath := pathJoin(minioMetaBucketDir, bucketMetaPrefix, bucket, object, fs.metaJSONFile)

if bucket != minioMetaBucket {

rwlk, lerr := fs.rwPool.Write(fsMetaPath)

if lerr == nil {

// This close will allow for fs locks to be synchronized on `fs.json`.

defer rwlk.Close()

}

if lerr != nil && lerr != errFileNotFound {

logger.LogIf(ctx, lerr)

return toObjectErr(lerr, bucket, object)

}

}

// Delete the object.

if err := fsDeleteFile(ctx, pathJoin(fs.fsPath, bucket), pathJoin(fs.fsPath, bucket, object)); err != nil {

return toObjectErr(err, bucket, object)

}

if bucket != minioMetaBucket {

// Delete the metadata object.

err := fsDeleteFile(ctx, minioMetaBucketDir, fsMetaPath)

if err != nil && err != errFileNotFound {

return toObjectErr(err, bucket, object)

}

}

return nil

}