minio/fs-v1.go
2016-06-25 14:51:06 -07:00

519 lines
14 KiB
Go

/*
* Minio Cloud Storage, (C) 2016 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 main
import (
"crypto/md5"
"encoding/hex"
"encoding/json"
"io"
"os"
"path"
"path/filepath"
"sort"
"strings"
"github.com/minio/minio/pkg/disk"
"github.com/minio/minio/pkg/mimedb"
)
// fsObjects - Implements fs object layer.
type fsObjects struct {
storage StorageAPI
physicalDisk string
// List pool management.
listPool *treeWalkPool
}
// creates format.json, the FS format info in minioMetaBucket.
func initFormatFS(storageDisk StorageAPI) error {
return writeFSFormatData(storageDisk, newFSFormatV1())
}
// loads format.json from minioMetaBucket if it exists.
func loadFormatFS(storageDisk StorageAPI) (format formatConfigV1, err error) {
// Reads entire `format.json`.
buf, err := storageDisk.ReadAll(minioMetaBucket, fsFormatJSONFile)
if err != nil {
return formatConfigV1{}, err
}
// Unmarshal format config.
if err = json.Unmarshal(buf, &format); err != nil {
return formatConfigV1{}, err
}
// Return structured `format.json`.
return format, nil
}
// Should be called when process shuts down.
func shutdownFS(storage StorageAPI) {
_, err := storage.ListDir(minioMetaBucket, mpartMetaPrefix)
if err != errFileNotFound {
// Multipart directory is not empty hence do not remove .minio volume.
os.Exit(0)
}
prefix := ""
if err := cleanupDir(storage, minioMetaBucket, prefix); err != nil {
os.Exit(0)
return
}
storage.DeleteVol(minioMetaBucket)
os.Exit(0)
}
// newFSObjects - initialize new fs object layer.
func newFSObjects(disk string) (ObjectLayer, error) {
storage, err := newStorageAPI(disk)
if err != nil {
return nil, err
}
// Runs house keeping code, like creating minioMetaBucket, cleaning up tmp files etc.
fsHouseKeeping(storage)
// loading format.json from minioMetaBucket.
// Note: The format.json content is ignored, reserved for future use.
_, err = loadFormatFS(storage)
if err != nil {
if err == errFileNotFound {
// format.json doesn't exist, create it inside minioMetaBucket.
err = initFormatFS(storage)
if err != nil {
return nil, err
}
} else {
return nil, err
}
}
// Register the callback that should be called when the process shuts down.
registerShutdown(func() {
shutdownFS(storage)
})
// Return successfully initialized object layer.
return fsObjects{
storage: storage,
physicalDisk: disk,
listPool: newTreeWalkPool(globalLookupTimeout),
}, nil
}
// StorageInfo - returns underlying storage statistics.
func (fs fsObjects) StorageInfo() StorageInfo {
info, err := disk.GetInfo(fs.physicalDisk)
fatalIf(err, "Unable to get disk info "+fs.physicalDisk)
return StorageInfo{
Total: info.Total,
Free: info.Free,
}
}
/// Bucket operations
// MakeBucket - make a bucket.
func (fs fsObjects) MakeBucket(bucket string) error {
// Verify if bucket is valid.
if !IsValidBucketName(bucket) {
return BucketNameInvalid{Bucket: bucket}
}
if err := fs.storage.MakeVol(bucket); err != nil {
return toObjectErr(err, bucket)
}
return nil
}
// GetBucketInfo - get bucket info.
func (fs fsObjects) GetBucketInfo(bucket string) (BucketInfo, error) {
// Verify if bucket is valid.
if !IsValidBucketName(bucket) {
return BucketInfo{}, BucketNameInvalid{Bucket: bucket}
}
vi, err := fs.storage.StatVol(bucket)
if err != nil {
return BucketInfo{}, toObjectErr(err, bucket)
}
return BucketInfo{
Name: bucket,
Created: vi.Created,
}, nil
}
// ListBuckets - list buckets.
func (fs fsObjects) ListBuckets() ([]BucketInfo, error) {
var bucketInfos []BucketInfo
vols, err := fs.storage.ListVols()
if err != nil {
return nil, toObjectErr(err)
}
for _, vol := range vols {
// StorageAPI can send volume names which are incompatible
// with buckets, handle it and skip them.
if !IsValidBucketName(vol.Name) {
continue
}
bucketInfos = append(bucketInfos, BucketInfo{
Name: vol.Name,
Created: vol.Created,
})
}
sort.Sort(byBucketName(bucketInfos))
return bucketInfos, nil
}
// DeleteBucket - delete a bucket.
func (fs fsObjects) DeleteBucket(bucket string) error {
// Verify if bucket is valid.
if !IsValidBucketName(bucket) {
return BucketNameInvalid{Bucket: bucket}
}
if err := fs.storage.DeleteVol(bucket); err != nil {
return toObjectErr(err, bucket)
}
return nil
}
/// Object Operations
// GetObject - get an object.
func (fs fsObjects) GetObject(bucket, object string, offset int64, length int64, writer io.Writer) (err 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}
}
var totalLeft = length
buf := make([]byte, readSizeV1) // Allocate a 128KiB staging buffer.
for totalLeft > 0 {
// Figure out the right size for the buffer.
curLeft := int64(readSizeV1)
if totalLeft < readSizeV1 {
curLeft = totalLeft
}
// Reads the file at offset.
nr, er := fs.storage.ReadFile(bucket, object, offset, buf[:curLeft])
if nr > 0 {
// Write to response writer.
nw, ew := writer.Write(buf[0:nr])
if nw > 0 {
// Decrement whats left to write.
totalLeft -= int64(nw)
// Progress the offset
offset += int64(nw)
}
if ew != nil {
err = ew
break
}
if nr != int64(nw) {
err = io.ErrShortWrite
break
}
}
if er == io.EOF || er == io.ErrUnexpectedEOF {
break
}
if er != nil {
err = er
break
}
}
// Returns any error.
return toObjectErr(err, bucket, object)
}
// GetObjectInfo - get object info.
func (fs fsObjects) 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})
}
fi, err := fs.storage.StatFile(bucket, object)
if err != nil {
return ObjectInfo{}, toObjectErr(err, bucket, object)
}
// Guess content-type from the extension if possible.
contentType := ""
if objectExt := filepath.Ext(object); objectExt != "" {
if content, ok := mimedb.DB[strings.ToLower(strings.TrimPrefix(objectExt, "."))]; ok {
contentType = content.ContentType
}
}
return ObjectInfo{
Bucket: bucket,
Name: object,
ModTime: fi.ModTime,
Size: fi.Size,
IsDir: fi.Mode.IsDir(),
ContentType: contentType,
MD5Sum: "", // Read from metadata.
}, nil
}
// PutObject - create an object.
func (fs fsObjects) 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}
}
if !IsValidObjectName(object) {
return "", ObjectNameInvalid{
Bucket: bucket,
Object: object,
}
}
uniqueID := getUUID()
// 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 := path.Join(tmpMetaPrefix, uniqueID)
// Initialize md5 writer.
md5Writer := md5.New()
if size == 0 {
// For size 0 we write a 0byte file.
err := fs.storage.AppendFile(minioMetaBucket, tempObj, []byte(""))
if err != nil {
return "", toObjectErr(err, bucket, object)
}
} else {
// Allocate a buffer to Read() the object upload stream.
buf := make([]byte, 32*1024)
// Read the buffer till io.EOF and append the read data to
// the temporary file.
for {
n, rErr := data.Read(buf)
if rErr != nil && rErr != io.EOF {
return "", toObjectErr(rErr, bucket, object)
}
if n > 0 {
// Update md5 writer.
md5Writer.Write(buf[:n])
wErr := fs.storage.AppendFile(minioMetaBucket, tempObj, buf[:n])
if wErr != nil {
return "", toObjectErr(wErr, bucket, object)
}
}
if rErr == io.EOF {
break
}
}
}
newMD5Hex := hex.EncodeToString(md5Writer.Sum(nil))
// md5Hex representation.
var md5Hex string
if len(metadata) != 0 {
md5Hex = metadata["md5Sum"]
}
if md5Hex != "" {
if newMD5Hex != md5Hex {
return "", BadDigest{md5Hex, newMD5Hex}
}
}
// Entire object was written to the temp location, now it's safe to rename it
// to the actual location.
err := fs.storage.RenameFile(minioMetaBucket, tempObj, bucket, object)
if err != nil {
return "", toObjectErr(err, bucket, object)
}
// Return md5sum, successfully wrote object.
return newMD5Hex, nil
}
func (fs fsObjects) 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}
}
if err := fs.storage.DeleteFile(bucket, object); err != nil {
return toObjectErr(err, bucket, object)
}
return nil
}
// Checks whether bucket exists.
func isBucketExist(storage StorageAPI, bucketName string) bool {
// Check whether bucket exists.
_, err := storage.StatVol(bucketName)
if err != nil {
if err == errVolumeNotFound {
return false
}
errorIf(err, "Stat failed on bucket "+bucketName+".")
return false
}
return true
}
func (fs fsObjects) listObjects(bucket, prefix, marker, delimiter string, maxKeys int) (ListObjectsInfo, error) {
// Convert entry to FileInfo
entryToFileInfo := func(entry string) (fileInfo FileInfo, err error) {
if strings.HasSuffix(entry, slashSeparator) {
// Object name needs to be full path.
fileInfo.Name = entry
fileInfo.Mode = os.ModeDir
return
}
if fileInfo, err = fs.storage.StatFile(bucket, entry); err != nil {
return
}
// Object name needs to be full path.
fileInfo.Name = entry
return
}
// Verify if bucket is valid.
if !IsValidBucketName(bucket) {
return ListObjectsInfo{}, BucketNameInvalid{Bucket: bucket}
}
// Verify if bucket exists.
if !isBucketExist(fs.storage, bucket) {
return ListObjectsInfo{}, BucketNotFound{Bucket: bucket}
}
if !IsValidObjectPrefix(prefix) {
return ListObjectsInfo{}, ObjectNameInvalid{Bucket: bucket, Object: prefix}
}
// Verify if delimiter is anything other than '/', which we do not support.
if delimiter != "" && delimiter != slashSeparator {
return ListObjectsInfo{}, UnsupportedDelimiter{
Delimiter: delimiter,
}
}
// Verify if marker has prefix.
if marker != "" {
if !strings.HasPrefix(marker, prefix) {
return ListObjectsInfo{}, InvalidMarkerPrefixCombination{
Marker: marker,
Prefix: prefix,
}
}
}
// With max keys of zero we have reached eof, return right here.
if maxKeys == 0 {
return ListObjectsInfo{}, nil
}
// For delimiter and prefix as '/' we do not list anything at all
// since according to s3 spec we stop at the 'delimiter'
// along // with the prefix. On a flat namespace with 'prefix'
// as '/' we don't have any entries, since all the keys are
// of form 'keyName/...'
if delimiter == slashSeparator && prefix == slashSeparator {
return ListObjectsInfo{}, nil
}
// Over flowing count - reset to maxObjectList.
if maxKeys < 0 || maxKeys > maxObjectList {
maxKeys = maxObjectList
}
// Default is recursive, if delimiter is set then list non recursive.
recursive := true
if delimiter == slashSeparator {
recursive = false
}
walkResultCh, endWalkCh := fs.listPool.Release(listParams{bucket, recursive, marker, prefix})
if walkResultCh == nil {
endWalkCh = make(chan struct{})
walkResultCh = fs.startTreeWalk(bucket, prefix, marker, recursive, func(bucket, object string) bool {
return !strings.HasSuffix(object, slashSeparator)
}, endWalkCh)
}
var fileInfos []FileInfo
var eof bool
var nextMarker string
for i := 0; i < maxKeys; {
walkResult, ok := <-walkResultCh
if !ok {
// Closed channel.
eof = true
break
}
// For any walk error return right away.
if walkResult.err != nil {
// File not found is a valid case.
if walkResult.err == errFileNotFound {
return ListObjectsInfo{}, nil
}
return ListObjectsInfo{}, toObjectErr(walkResult.err, bucket, prefix)
}
fileInfo, err := entryToFileInfo(walkResult.entry)
if err != nil {
return ListObjectsInfo{}, nil
}
nextMarker = fileInfo.Name
fileInfos = append(fileInfos, fileInfo)
if walkResult.end {
eof = true
break
}
i++
}
params := listParams{bucket, recursive, nextMarker, prefix}
if !eof {
fs.listPool.Set(params, walkResultCh, endWalkCh)
}
result := ListObjectsInfo{IsTruncated: !eof}
for _, fileInfo := range fileInfos {
// With delimiter set we fill in NextMarker and Prefixes.
if delimiter == slashSeparator {
result.NextMarker = fileInfo.Name
if fileInfo.Mode.IsDir() {
result.Prefixes = append(result.Prefixes, fileInfo.Name)
continue
}
}
result.Objects = append(result.Objects, ObjectInfo{
Name: fileInfo.Name,
ModTime: fileInfo.ModTime,
Size: fileInfo.Size,
IsDir: false,
})
}
return result, nil
}
// ListObjects - list all objects.
func (fs fsObjects) ListObjects(bucket, prefix, marker, delimiter string, maxKeys int) (ListObjectsInfo, error) {
return fs.listObjects(bucket, prefix, marker, delimiter, maxKeys)
}