You can not select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
minio/xl-v1-object.go

393 lines
11 KiB

package main
import (
"crypto/md5"
"encoding/hex"
"io"
"path"
"path/filepath"
"strings"
"sync"
"time"
"github.com/minio/minio/pkg/mimedb"
)
/// Object Operations
// GetObject - get an object.
func (xl xlObjects) GetObject(bucket, object string, startOffset int64, length int64, writer io.Writer) error {
// Verify if bucket is valid.
if !IsValidBucketName(bucket) {
return BucketNameInvalid{Bucket: bucket}
}
// Verify if object is valid.
if !IsValidObjectName(object) {
return ObjectNameInvalid{Bucket: bucket, Object: object}
}
// Lock the object before reading.
nsMutex.RLock(bucket, object)
defer nsMutex.RUnlock(bucket, object)
// Read metadata associated with the object.
xlMeta, err := xl.readXLMetadata(bucket, object)
if err != nil {
return toObjectErr(err, bucket, object)
}
// List all online disks.
onlineDisks, _, err := xl.listOnlineDisks(bucket, object)
if err != nil {
return toObjectErr(err, bucket, object)
}
// Initialize a new erasure with online disks, with previous block distribution.
erasure := newErasure(onlineDisks, xlMeta.Erasure.Distribution)
// Get part index offset.
partIndex, partOffset, err := xlMeta.objectToPartOffset(startOffset)
if err != nil {
return toObjectErr(err, bucket, object)
}
for ; partIndex < len(xlMeta.Parts); partIndex++ {
part := xlMeta.Parts[partIndex]
totalLeft := part.Size
beginOffset := int64(0)
for totalLeft > 0 {
var curBlockSize int64
if xlMeta.Erasure.BlockSize < totalLeft {
curBlockSize = xlMeta.Erasure.BlockSize
} else {
curBlockSize = totalLeft
}
var buffer = make([]byte, curBlockSize)
var n int64
n, err = erasure.ReadFile(bucket, pathJoin(object, part.Name), partOffset, beginOffset, buffer)
if err != nil {
return err
}
if length > int64(len(buffer)) {
var m int
m, err = writer.Write(buffer)
if err != nil {
return err
}
length -= int64(m)
} else {
_, err = writer.Write(buffer[:length])
if err != nil {
return err
}
return nil
}
totalLeft -= partOffset + n
beginOffset += n
// Reset part offset to 0 to read rest of the parts from the beginning.
partOffset = 0
}
}
return nil
}
// GetObjectInfo - get object info.
func (xl xlObjects) GetObjectInfo(bucket, object string) (ObjectInfo, error) {
// Verify if bucket is valid.
if !IsValidBucketName(bucket) {
return ObjectInfo{}, BucketNameInvalid{Bucket: bucket}
}
// Verify if object is valid.
if !IsValidObjectName(object) {
return ObjectInfo{}, ObjectNameInvalid{Bucket: bucket, Object: object}
}
nsMutex.RLock(bucket, object)
defer nsMutex.RUnlock(bucket, object)
info, err := xl.getObjectInfo(bucket, object)
if err != nil {
return ObjectInfo{}, toObjectErr(err, bucket, object)
}
return info, nil
}
// getObjectInfo - get object info.
func (xl xlObjects) getObjectInfo(bucket, object string) (objInfo ObjectInfo, err error) {
var xlMeta xlMetaV1
xlMeta, err = xl.readXLMetadata(bucket, object)
if err != nil {
// Return error.
return ObjectInfo{}, err
}
objInfo = ObjectInfo{}
objInfo.IsDir = false
objInfo.Bucket = bucket
objInfo.Name = object
objInfo.Size = xlMeta.Stat.Size
objInfo.ModTime = xlMeta.Stat.ModTime
objInfo.MD5Sum = xlMeta.Meta["md5Sum"]
objInfo.ContentType = xlMeta.Meta["content-type"]
objInfo.ContentEncoding = xlMeta.Meta["content-encoding"]
return objInfo, nil
}
// renameObject - renaming all source objects to destination object across all disks.
func (xl xlObjects) renameObject(srcBucket, srcObject, dstBucket, dstObject string) error {
// Initialize sync waitgroup.
var wg = &sync.WaitGroup{}
// Initialize list of errors.
var errs = make([]error, len(xl.storageDisks))
// Rename file on all underlying storage disks.
for index, disk := range xl.storageDisks {
// Append "/" as srcObject and dstObject are either leaf-dirs or non-leaf-dris.
// If srcObject is an object instead of prefix we just rename the leaf-dir and
// not rename the part and metadata files separately.
wg.Add(1)
go func(index int, disk StorageAPI) {
defer wg.Done()
err := disk.RenameFile(srcBucket, retainSlash(srcObject), dstBucket, retainSlash(dstObject))
if err != nil {
errs[index] = err
}
errs[index] = nil
}(index, disk)
}
// Wait for all RenameFile to finish.
wg.Wait()
// Gather err count.
var errCount = 0
for _, err := range errs {
if err == nil {
continue
}
errCount++
}
// We can safely allow RenameFile errors up to len(xl.storageDisks) - xl.writeQuorum
// otherwise return failure. Cleanup successful renames.
if errCount > len(xl.storageDisks)-xl.writeQuorum {
// Special condition if readQuorum exists, then return success.
if errCount <= len(xl.storageDisks)-xl.readQuorum {
return nil
}
// Rename back the object on disks where RenameFile succeeded
for index, disk := range xl.storageDisks {
// Rename back the object in parallel to reduce overall disk latency
wg.Add(1)
go func(index int, disk StorageAPI) {
defer wg.Done()
if errs[index] != nil {
return
}
_ = disk.RenameFile(dstBucket, retainSlash(dstObject), srcBucket, retainSlash(srcObject))
}(index, disk)
}
wg.Wait()
return errWriteQuorum
}
return nil
}
// PutObject - create an object.
func (xl xlObjects) PutObject(bucket string, object string, size int64, data io.Reader, metadata map[string]string) (string, error) {
// Verify if bucket is valid.
if !IsValidBucketName(bucket) {
return "", BucketNameInvalid{Bucket: bucket}
}
// Verify bucket exists.
if !xl.isBucketExist(bucket) {
return "", BucketNotFound{Bucket: bucket}
}
if !IsValidObjectName(object) {
return "", ObjectNameInvalid{
Bucket: bucket,
Object: object,
}
}
// No metadata is set, allocate a new one.
if metadata == nil {
metadata = make(map[string]string)
}
nsMutex.Lock(bucket, object)
defer nsMutex.Unlock(bucket, object)
uniqueID := getUUID()
tempErasureObj := path.Join(tmpMetaPrefix, uniqueID, "object1")
tempObj := path.Join(tmpMetaPrefix, uniqueID)
// Initialize xl meta.
xlMeta := newXLMetaV1(xl.dataBlocks, xl.parityBlocks)
// List all online disks.
onlineDisks, higherVersion, err := xl.listOnlineDisks(bucket, object)
if err != nil {
return "", toObjectErr(err, bucket, object)
}
// Increment version only if we have online disks less than configured storage disks.
if diskCount(onlineDisks) < len(xl.storageDisks) {
higherVersion++
}
// Initialize a new erasure with online disks and new distribution.
erasure := newErasure(onlineDisks, xlMeta.Erasure.Distribution)
// Initialize md5 writer.
md5Writer := md5.New()
// Allocated blockSized buffer for reading.
buf := make([]byte, blockSizeV1)
for {
var n int
n, err = io.ReadFull(data, buf)
if err == io.EOF {
break
}
if err != nil && err != io.ErrUnexpectedEOF {
return "", toObjectErr(err, bucket, object)
}
// Update md5 writer.
md5Writer.Write(buf[:n])
var m int64
m, err = erasure.AppendFile(minioMetaBucket, tempErasureObj, buf[:n])
if err != nil {
return "", toObjectErr(err, minioMetaBucket, tempErasureObj)
}
if m != int64(len(buf[:n])) {
return "", toObjectErr(errUnexpected, bucket, object)
}
}
// Save additional erasureMetadata.
modTime := time.Now().UTC()
newMD5Hex := hex.EncodeToString(md5Writer.Sum(nil))
// Update the md5sum if not set with the newly calculated one.
if len(metadata["md5Sum"]) == 0 {
metadata["md5Sum"] = newMD5Hex
}
// If not set default to "application/octet-stream"
if metadata["content-type"] == "" {
contentType := "application/octet-stream"
if objectExt := filepath.Ext(object); objectExt != "" {
content, ok := mimedb.DB[strings.ToLower(strings.TrimPrefix(objectExt, "."))]
if ok {
contentType = content.ContentType
}
}
metadata["content-type"] = contentType
}
// md5Hex representation.
md5Hex := metadata["md5Sum"]
if md5Hex != "" {
if newMD5Hex != md5Hex {
return "", BadDigest{md5Hex, newMD5Hex}
}
}
// Check if an object is present as one of the parent dir.
if xl.parentDirIsObject(bucket, path.Dir(object)) {
return "", toObjectErr(errFileAccessDenied, bucket, object)
}
// Rename if an object already exists to temporary location.
newUniqueID := getUUID()
err = xl.renameObject(bucket, object, minioMetaBucket, path.Join(tmpMetaPrefix, newUniqueID))
if err != nil {
return "", toObjectErr(err, bucket, object)
}
// Fill all the necessary metadata.
xlMeta.Meta = metadata
xlMeta.Stat.Size = size
xlMeta.Stat.ModTime = modTime
xlMeta.Stat.Version = higherVersion
xlMeta.AddObjectPart(1, "object1", newMD5Hex, xlMeta.Stat.Size)
// Write `xl.json` metadata.
if err = xl.writeXLMetadata(minioMetaBucket, tempObj, xlMeta); err != nil {
return "", toObjectErr(err, bucket, object)
}
// Rename the successfully written tempoary object to final location.
err = xl.renameObject(minioMetaBucket, tempObj, bucket, object)
if err != nil {
return "", toObjectErr(err, bucket, object)
}
// Delete the temporary object.
xl.deleteObject(minioMetaBucket, path.Join(tmpMetaPrefix, newUniqueID))
// Return md5sum, successfully wrote object.
return newMD5Hex, nil
}
// deleteObject - deletes a regular object.
func (xl xlObjects) deleteObject(bucket, object string) error {
// Initialize sync waitgroup.
var wg = &sync.WaitGroup{}
// Initialize list of errors.
var dErrs = make([]error, len(xl.storageDisks))
for index, disk := range xl.storageDisks {
wg.Add(1)
go func(index int, disk StorageAPI) {
defer wg.Done()
err := cleanupDir(disk, bucket, object)
if err != nil {
dErrs[index] = err
return
}
dErrs[index] = nil
}(index, disk)
}
// Wait for all routines to finish.
wg.Wait()
var fileNotFoundCnt, deleteFileErr int
// Count for specific errors.
for _, err := range dErrs {
if err == nil {
continue
}
// If file not found, count them.
if err == errFileNotFound {
fileNotFoundCnt++
continue
}
// Update error counter separately.
deleteFileErr++
}
// Return err if all disks report file not found.
if fileNotFoundCnt == len(xl.storageDisks) {
return errFileNotFound
} else if deleteFileErr > len(xl.storageDisks)-xl.writeQuorum {
// Return errWriteQuorum if errors were more than
// allowed write quorum.
return errWriteQuorum
}
return nil
}
// DeleteObject - delete the object.
func (xl xlObjects) DeleteObject(bucket, object string) error {
// Verify if bucket is valid.
if !IsValidBucketName(bucket) {
return BucketNameInvalid{Bucket: bucket}
}
if !IsValidObjectName(object) {
return ObjectNameInvalid{Bucket: bucket, Object: object}
}
nsMutex.Lock(bucket, object)
defer nsMutex.Unlock(bucket, object)
xl.deleteObject(bucket, object)
return nil
}