minio/cmd/fs-v1-metadata.go
Praveen raj Mani c7722fbb1b Simplify pkg mimedb (#6549)
Content-Type resolution can now use a function `TypeByExtension(extension)` 
to resolve to the respective content-type.
2018-10-02 11:48:17 +05:30

280 lines
7.2 KiB
Go

/*
* Minio Cloud Storage, (C) 2016, 2017, 2017 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 (
"context"
"encoding/hex"
"encoding/json"
"io"
"io/ioutil"
"os"
pathutil "path"
"github.com/minio/minio/cmd/logger"
"github.com/minio/minio/pkg/lock"
"github.com/minio/minio/pkg/mimedb"
"github.com/tidwall/gjson"
)
// FS format, and object metadata.
const (
// fs.json object metadata.
fsMetaJSONFile = "fs.json"
)
// FS metadata constants.
const (
// FS backend meta 1.0.0 version.
fsMetaVersion100 = "1.0.0"
// FS backend meta 1.0.1 version.
fsMetaVersion101 = "1.0.1"
// FS backend meta 1.0.2
// Removed the fields "Format" and "Minio" from fsMetaV1 as they were unused. Added "Checksum" field - to be used in future for bit-rot protection.
fsMetaVersion = "1.0.2"
// Add more constants here.
)
// FSChecksumInfoV1 - carries checksums of individual blocks on disk.
type FSChecksumInfoV1 struct {
Algorithm string
Blocksize int64
Hashes [][]byte
}
// MarshalJSON marshals the FSChecksumInfoV1 struct
func (c FSChecksumInfoV1) MarshalJSON() ([]byte, error) {
type checksuminfo struct {
Algorithm string `json:"algorithm"`
Blocksize int64 `json:"blocksize"`
Hashes []string `json:"hashes"`
}
var hashes []string
for _, h := range c.Hashes {
hashes = append(hashes, hex.EncodeToString(h))
}
info := checksuminfo{
Algorithm: c.Algorithm,
Hashes: hashes,
Blocksize: c.Blocksize,
}
return json.Marshal(info)
}
// UnmarshalJSON unmarshals the the given data into the FSChecksumInfoV1 struct
func (c *FSChecksumInfoV1) UnmarshalJSON(data []byte) error {
type checksuminfo struct {
Algorithm string `json:"algorithm"`
Blocksize int64 `json:"blocksize"`
Hashes []string `json:"hashes"`
}
var info checksuminfo
err := json.Unmarshal(data, &info)
if err != nil {
return err
}
c.Algorithm = info.Algorithm
c.Blocksize = info.Blocksize
var hashes [][]byte
for _, hashStr := range info.Hashes {
h, err := hex.DecodeString(hashStr)
if err != nil {
return err
}
hashes = append(hashes, h)
}
c.Hashes = hashes
return nil
}
// A fsMetaV1 represents a metadata header mapping keys to sets of values.
type fsMetaV1 struct {
Version string `json:"version"`
// checksums of blocks on disk.
Checksum FSChecksumInfoV1 `json:"checksum,omitempty"`
// Metadata map for current object.
Meta map[string]string `json:"meta,omitempty"`
// parts info for current object - used in encryption.
Parts []objectPartInfo `json:"parts,omitempty"`
}
// IsValid - tells if the format is sane by validating the version
// string and format style.
func (m fsMetaV1) IsValid() bool {
return isFSMetaValid(m.Version)
}
// Verifies if the backend format metadata is same by validating
// the version string.
func isFSMetaValid(version string) bool {
return (version == fsMetaVersion || version == fsMetaVersion100 || version == fsMetaVersion101)
}
// Converts metadata to object info.
func (m fsMetaV1) ToObjectInfo(bucket, object string, fi os.FileInfo) ObjectInfo {
if len(m.Meta) == 0 {
m.Meta = make(map[string]string)
}
// Guess content-type from the extension if possible.
if m.Meta["content-type"] == "" {
m.Meta["content-type"] = mimedb.TypeByExtension(pathutil.Ext(object))
}
if hasSuffix(object, slashSeparator) {
m.Meta["etag"] = emptyETag // For directories etag is d41d8cd98f00b204e9800998ecf8427e
m.Meta["content-type"] = "application/octet-stream"
}
objInfo := ObjectInfo{
Bucket: bucket,
Name: object,
}
// We set file info only if its valid.
objInfo.ModTime = timeSentinel
if fi != nil {
objInfo.ModTime = fi.ModTime()
objInfo.Size = fi.Size()
if fi.IsDir() {
// Directory is always 0 bytes in S3 API, treat it as such.
objInfo.Size = 0
objInfo.IsDir = fi.IsDir()
}
}
objInfo.ETag = extractETag(m.Meta)
objInfo.ContentType = m.Meta["content-type"]
objInfo.ContentEncoding = m.Meta["content-encoding"]
if storageClass, ok := m.Meta[amzStorageClass]; ok {
objInfo.StorageClass = storageClass
} else {
objInfo.StorageClass = globalMinioDefaultStorageClass
}
// etag/md5Sum has already been extracted. We need to
// remove to avoid it from appearing as part of
// response headers. e.g, X-Minio-* or X-Amz-*.
objInfo.UserDefined = cleanMetadata(m.Meta)
// All the parts per object.
objInfo.Parts = m.Parts
// Success..
return objInfo
}
func (m *fsMetaV1) WriteTo(lk *lock.LockedFile) (n int64, err error) {
if err = jsonSave(lk, m); err != nil {
return 0, err
}
fi, err := lk.Stat()
if err != nil {
return 0, err
}
return fi.Size(), nil
}
func parseFSVersion(fsMetaBuf []byte) string {
return gjson.GetBytes(fsMetaBuf, "version").String()
}
func parseFSMetaMap(fsMetaBuf []byte) map[string]string {
// Get xlMetaV1.Meta map.
metaMapResult := gjson.GetBytes(fsMetaBuf, "meta").Map()
metaMap := make(map[string]string)
for key, valResult := range metaMapResult {
metaMap[key] = valResult.String()
}
return metaMap
}
func parseFSPartsArray(fsMetaBuf []byte) []objectPartInfo {
// Get xlMetaV1.Parts array
var partsArray []objectPartInfo
partsArrayResult := gjson.GetBytes(fsMetaBuf, "parts")
partsArrayResult.ForEach(func(key, part gjson.Result) bool {
partJSON := part.String()
number := gjson.Get(partJSON, "number").Int()
name := gjson.Get(partJSON, "name").String()
etag := gjson.Get(partJSON, "etag").String()
size := gjson.Get(partJSON, "size").Int()
actualSize := gjson.Get(partJSON, "actualSize").Int()
partsArray = append(partsArray, objectPartInfo{
Number: int(number),
Name: name,
ETag: etag,
Size: size,
ActualSize: int64(actualSize),
})
return true
})
return partsArray
}
func (m *fsMetaV1) ReadFrom(ctx context.Context, lk *lock.LockedFile) (n int64, err error) {
var fsMetaBuf []byte
fi, err := lk.Stat()
if err != nil {
logger.LogIf(ctx, err)
return 0, err
}
fsMetaBuf, err = ioutil.ReadAll(io.NewSectionReader(lk, 0, fi.Size()))
if err != nil {
logger.LogIf(ctx, err)
return 0, err
}
if len(fsMetaBuf) == 0 {
logger.LogIf(ctx, io.EOF)
return 0, io.EOF
}
// obtain version.
m.Version = parseFSVersion(fsMetaBuf)
// Verify if the format is valid, return corrupted format
// for unrecognized formats.
if !isFSMetaValid(m.Version) {
logger.GetReqInfo(ctx).AppendTags("file", lk.Name())
logger.LogIf(ctx, errCorruptedFormat)
return 0, errCorruptedFormat
}
// obtain parts information
m.Parts = parseFSPartsArray(fsMetaBuf)
// obtain metadata.
m.Meta = parseFSMetaMap(fsMetaBuf)
// Success.
return int64(len(fsMetaBuf)), nil
}
// newFSMetaV1 - initializes new fsMetaV1.
func newFSMetaV1() (fsMeta fsMetaV1) {
fsMeta = fsMetaV1{}
fsMeta.Version = fsMetaVersion
return fsMeta
}