frostfs-s3-gw/legacy/object-api-common.go
2020-07-09 12:28:51 +03:00

400 lines
11 KiB
Go

/*
* MinIO Cloud Storage, (C) 2016-2019 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 legacy
import (
"context"
"sync"
"strings"
humanize "github.com/dustin/go-humanize"
"github.com/minio/minio/legacy/logger"
)
const (
// Block size used for all internal operations version 1.
blockSizeV1 = 10 * humanize.MiByte
// Staging buffer read size for all internal operations version 1.
readSizeV1 = 1 * humanize.MiByte
// Buckets meta prefix.
bucketMetaPrefix = "buckets"
// ETag (hex encoded md5sum) of empty string.
emptyETag = "d41d8cd98f00b204e9800998ecf8427e"
)
// Global object layer mutex, used for safely updating object layer.
var globalObjLayerMutex sync.RWMutex
// Global object layer, only accessed by globalObjectAPI.
var globalObjectAPI ObjectLayer
//Global cacheObjects, only accessed by newCacheObjectsFn().
var globalCacheObjectAPI CacheObjectLayer
// Checks if the object is a directory, this logic uses
// if size == 0 and object ends with SlashSeparator then
// returns true.
func isObjectDir(object string, size int64) bool {
return HasSuffix(object, SlashSeparator) && size == 0
}
// Converts just bucket, object metadata into ObjectInfo datatype.
func dirObjectInfo(bucket, object string, size int64, metadata map[string]string) ObjectInfo {
// 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.
etag := metadata["etag"]
delete(metadata, "etag")
if etag == "" {
etag = emptyETag
}
return ObjectInfo{
Bucket: bucket,
Name: object,
ModTime: UTCNow(),
ContentType: "application/octet-stream",
IsDir: true,
Size: size,
ETag: etag,
UserDefined: metadata,
}
}
// Depending on the disk type network or local, initialize storage API.
func newStorageAPI(endpoint Endpoint) (storage StorageAPI, err error) {
if endpoint.IsLocal {
storage, err := newPosix(endpoint.Path, endpoint.Host)
if err != nil {
return nil, err
}
return &posixDiskIDCheck{storage: storage}, nil
}
return newStorageRESTClient(endpoint), nil
}
// Cleanup a directory recursively.
func cleanupDir(ctx context.Context, storage StorageAPI, volume, dirPath string) error {
var delFunc func(string) error
// Function to delete entries recursively.
delFunc = func(entryPath string) error {
if !HasSuffix(entryPath, SlashSeparator) {
// Delete the file entry.
err := storage.DeleteFile(volume, entryPath)
logger.LogIf(ctx, err)
return err
}
// If it's a directory, list and call delFunc() for each entry.
entries, err := storage.ListDir(volume, entryPath, -1, "")
// If entryPath prefix never existed, safe to ignore.
if err == errFileNotFound {
return nil
} else if err != nil { // For any other errors fail.
logger.LogIf(ctx, err)
return err
} // else on success..
// Entry path is empty, just delete it.
if len(entries) == 0 {
err = storage.DeleteFile(volume, entryPath)
logger.LogIf(ctx, err)
return err
}
// Recurse and delete all other entries.
for _, entry := range entries {
if err = delFunc(pathJoin(entryPath, entry)); err != nil {
return err
}
}
return nil
}
err := delFunc(retainSlash(pathJoin(dirPath)))
return err
}
func listObjectsNonSlash(ctx context.Context, bucket, prefix, marker, delimiter string, maxKeys int, tpool *TreeWalkPool, listDir ListDirFunc, getObjInfo func(context.Context, string, string) (ObjectInfo, error), getObjectInfoDirs ...func(context.Context, string, string) (ObjectInfo, error)) (loi ListObjectsInfo, err error) {
endWalkCh := make(chan struct{})
defer close(endWalkCh)
recursive := true
walkResultCh := startTreeWalk(ctx, bucket, prefix, "", recursive, listDir, endWalkCh)
var objInfos []ObjectInfo
var eof bool
var prevPrefix string
for {
if len(objInfos) == maxKeys {
break
}
result, ok := <-walkResultCh
if !ok {
eof = true
break
}
var objInfo ObjectInfo
var err error
index := strings.Index(strings.TrimPrefix(result.entry, prefix), delimiter)
if index == -1 {
objInfo, err = getObjInfo(ctx, bucket, result.entry)
if err != nil {
// Ignore errFileNotFound as the object might have got
// deleted in the interim period of listing and getObjectInfo(),
// ignore quorum error as it might be an entry from an outdated disk.
if IsErrIgnored(err, []error{
errFileNotFound,
errXLReadQuorum,
}...) {
continue
}
return loi, toObjectErr(err, bucket, prefix)
}
} else {
index = len(prefix) + index + len(delimiter)
currPrefix := result.entry[:index]
if currPrefix == prevPrefix {
continue
}
prevPrefix = currPrefix
objInfo = ObjectInfo{
Bucket: bucket,
Name: currPrefix,
IsDir: true,
}
}
if objInfo.Name <= marker {
continue
}
objInfos = append(objInfos, objInfo)
if result.end {
eof = true
break
}
}
result := ListObjectsInfo{}
for _, objInfo := range objInfos {
if objInfo.IsDir {
result.Prefixes = append(result.Prefixes, objInfo.Name)
continue
}
result.Objects = append(result.Objects, objInfo)
}
if !eof {
result.IsTruncated = true
if len(objInfos) > 0 {
result.NextMarker = objInfos[len(objInfos)-1].Name
}
}
return result, nil
}
// Walk a bucket, optionally prefix recursively, until we have returned
// all the content to objectInfo channel, it is callers responsibility
// to allocate a receive channel for ObjectInfo, upon any unhandled
// error walker returns error. Optionally if context.Done() is received
// then Walk() stops the walker.
func fsWalk(ctx context.Context, obj ObjectLayer, bucket, prefix string, listDir ListDirFunc, results chan<- ObjectInfo, getObjInfo func(context.Context, string, string) (ObjectInfo, error), getObjectInfoDirs ...func(context.Context, string, string) (ObjectInfo, error)) error {
if err := checkListObjsArgs(ctx, bucket, prefix, "", obj); err != nil {
// Upon error close the channel.
close(results)
return err
}
walkResultCh := startTreeWalk(ctx, bucket, prefix, "", true, listDir, ctx.Done())
go func() {
defer close(results)
for {
walkResult, ok := <-walkResultCh
if !ok {
break
}
var objInfo ObjectInfo
var err error
if HasSuffix(walkResult.entry, SlashSeparator) {
for _, getObjectInfoDir := range getObjectInfoDirs {
objInfo, err = getObjectInfoDir(ctx, bucket, walkResult.entry)
if err == nil {
break
}
if err == errFileNotFound {
err = nil
objInfo = ObjectInfo{
Bucket: bucket,
Name: walkResult.entry,
IsDir: true,
}
}
}
} else {
objInfo, err = getObjInfo(ctx, bucket, walkResult.entry)
}
if err != nil {
continue
}
results <- objInfo
if walkResult.end {
break
}
}
}()
return nil
}
func listObjects(ctx context.Context, obj ObjectLayer, bucket, prefix, marker, delimiter string, maxKeys int, tpool *TreeWalkPool, listDir ListDirFunc, getObjInfo func(context.Context, string, string) (ObjectInfo, error), getObjectInfoDirs ...func(context.Context, string, string) (ObjectInfo, error)) (loi ListObjectsInfo, err error) {
if delimiter != SlashSeparator && delimiter != "" {
return listObjectsNonSlash(ctx, bucket, prefix, marker, delimiter, maxKeys, tpool, listDir, getObjInfo, getObjectInfoDirs...)
}
if err := checkListObjsArgs(ctx, bucket, prefix, marker, obj); err != nil {
return loi, err
}
// Marker is set validate pre-condition.
if marker != "" {
// Marker not common with prefix is not implemented. Send an empty response
if !HasPrefix(marker, prefix) {
return loi, nil
}
}
// With max keys of zero we have reached eof, return right here.
if maxKeys == 0 {
return loi, 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 loi, 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 := tpool.Release(listParams{bucket, recursive, marker, prefix})
if walkResultCh == nil {
endWalkCh = make(chan struct{})
walkResultCh = startTreeWalk(ctx, bucket, prefix, marker, recursive, listDir, endWalkCh)
}
var objInfos []ObjectInfo
var eof bool
var nextMarker string
// List until maxKeys requested.
for i := 0; i < maxKeys; {
walkResult, ok := <-walkResultCh
if !ok {
// Closed channel.
eof = true
break
}
var objInfo ObjectInfo
var err error
if HasSuffix(walkResult.entry, SlashSeparator) {
for _, getObjectInfoDir := range getObjectInfoDirs {
objInfo, err = getObjectInfoDir(ctx, bucket, walkResult.entry)
if err == nil {
break
}
if err == errFileNotFound {
err = nil
objInfo = ObjectInfo{
Bucket: bucket,
Name: walkResult.entry,
IsDir: true,
}
}
}
} else {
objInfo, err = getObjInfo(ctx, bucket, walkResult.entry)
}
if err != nil {
// Ignore errFileNotFound as the object might have got
// deleted in the interim period of listing and getObjectInfo(),
// ignore quorum error as it might be an entry from an outdated disk.
if IsErrIgnored(err, []error{
errFileNotFound,
errXLReadQuorum,
}...) {
continue
}
return loi, toObjectErr(err, bucket, prefix)
}
nextMarker = objInfo.Name
objInfos = append(objInfos, objInfo)
if walkResult.end {
eof = true
break
}
i++
}
// Save list routine for the next marker if we haven't reached EOF.
params := listParams{bucket, recursive, nextMarker, prefix}
if !eof {
tpool.Set(params, walkResultCh, endWalkCh)
}
result := ListObjectsInfo{}
for _, objInfo := range objInfos {
if objInfo.IsDir && delimiter == SlashSeparator {
result.Prefixes = append(result.Prefixes, objInfo.Name)
continue
}
result.Objects = append(result.Objects, objInfo)
}
if !eof {
result.IsTruncated = true
if len(objInfos) > 0 {
result.NextMarker = objInfos[len(objInfos)-1].Name
}
}
// Success.
return result, nil
}