seaweedfs/weed/filer2/leveldb/leveldb_store.go

218 lines
5.3 KiB
Go

package leveldb
import (
"bytes"
"context"
"fmt"
"github.com/syndtr/goleveldb/leveldb"
"github.com/syndtr/goleveldb/leveldb/opt"
leveldb_util "github.com/syndtr/goleveldb/leveldb/util"
"github.com/chrislusf/seaweedfs/weed/filer2"
"github.com/chrislusf/seaweedfs/weed/glog"
weed_util "github.com/chrislusf/seaweedfs/weed/util"
)
const (
DIR_FILE_SEPARATOR = byte(0x00)
)
func init() {
filer2.Stores = append(filer2.Stores, &LevelDBStore{})
}
type LevelDBStore struct {
db *leveldb.DB
}
func (store *LevelDBStore) GetName() string {
return "leveldb"
}
func (store *LevelDBStore) Initialize(configuration weed_util.Configuration, prefix string) (err error) {
dir := configuration.GetString(prefix + "dir")
return store.initialize(dir)
}
func (store *LevelDBStore) initialize(dir string) (err error) {
glog.Infof("filer store dir: %s", dir)
if err := weed_util.TestFolderWritable(dir); err != nil {
return fmt.Errorf("Check Level Folder %s Writable: %s", dir, err)
}
opts := &opt.Options{
BlockCacheCapacity: 32 * 1024 * 1024, // default value is 8MiB
WriteBuffer: 16 * 1024 * 1024, // default value is 4MiB
CompactionTableSizeMultiplier: 10,
}
if store.db, err = leveldb.OpenFile(dir, opts); err != nil {
glog.Infof("filer store open dir %s: %v", dir, err)
return
}
return
}
func (store *LevelDBStore) BeginTransaction(ctx context.Context) (context.Context, error) {
return ctx, nil
}
func (store *LevelDBStore) CommitTransaction(ctx context.Context) error {
return nil
}
func (store *LevelDBStore) RollbackTransaction(ctx context.Context) error {
return nil
}
func (store *LevelDBStore) InsertEntry(ctx context.Context, entry *filer2.Entry) (err error) {
key := genKey(entry.DirAndName())
value, err := entry.EncodeAttributesAndChunks()
if err != nil {
return fmt.Errorf("encoding %s %+v: %v", entry.FullPath, entry.Attr, err)
}
err = store.db.Put(key, value, nil)
if err != nil {
return fmt.Errorf("persisting %s : %v", entry.FullPath, err)
}
// println("saved", entry.FullPath, "chunks", len(entry.Chunks))
return nil
}
func (store *LevelDBStore) UpdateEntry(ctx context.Context, entry *filer2.Entry) (err error) {
return store.InsertEntry(ctx, entry)
}
func (store *LevelDBStore) FindEntry(ctx context.Context, fullpath filer2.FullPath) (entry *filer2.Entry, err error) {
key := genKey(fullpath.DirAndName())
data, err := store.db.Get(key, nil)
if err == leveldb.ErrNotFound {
return nil, filer2.ErrNotFound
}
if err != nil {
return nil, fmt.Errorf("get %s : %v", entry.FullPath, err)
}
entry = &filer2.Entry{
FullPath: fullpath,
}
err = entry.DecodeAttributesAndChunks(data)
if err != nil {
return entry, fmt.Errorf("decode %s : %v", entry.FullPath, err)
}
// println("read", entry.FullPath, "chunks", len(entry.Chunks), "data", len(data), string(data))
return entry, nil
}
func (store *LevelDBStore) DeleteEntry(ctx context.Context, fullpath filer2.FullPath) (err error) {
key := genKey(fullpath.DirAndName())
err = store.db.Delete(key, nil)
if err != nil {
return fmt.Errorf("delete %s : %v", fullpath, err)
}
return nil
}
func (store *LevelDBStore) DeleteFolderChildren(ctx context.Context, fullpath filer2.FullPath) (err error) {
batch := new(leveldb.Batch)
directoryPrefix := genDirectoryKeyPrefix(fullpath, "")
iter := store.db.NewIterator(&leveldb_util.Range{Start: directoryPrefix}, nil)
for iter.Next() {
key := iter.Key()
if !bytes.HasPrefix(key, directoryPrefix) {
break
}
fileName := getNameFromKey(key)
if fileName == "" {
continue
}
batch.Delete([]byte(genKey(string(fullpath), fileName)))
}
iter.Release()
err = store.db.Write(batch, nil)
if err != nil {
return fmt.Errorf("delete %s : %v", fullpath, err)
}
return nil
}
func (store *LevelDBStore) ListDirectoryEntries(ctx context.Context, fullpath filer2.FullPath, startFileName string, inclusive bool,
limit int) (entries []*filer2.Entry, err error) {
directoryPrefix := genDirectoryKeyPrefix(fullpath, "")
iter := store.db.NewIterator(&leveldb_util.Range{Start: genDirectoryKeyPrefix(fullpath, startFileName)}, nil)
for iter.Next() {
key := iter.Key()
if !bytes.HasPrefix(key, directoryPrefix) {
break
}
fileName := getNameFromKey(key)
if fileName == "" {
continue
}
if fileName == startFileName && !inclusive {
continue
}
limit--
if limit < 0 {
break
}
entry := &filer2.Entry{
FullPath: filer2.NewFullPath(string(fullpath), fileName),
}
if decodeErr := entry.DecodeAttributesAndChunks(iter.Value()); decodeErr != nil {
err = decodeErr
glog.V(0).Infof("list %s : %v", entry.FullPath, err)
break
}
entries = append(entries, entry)
}
iter.Release()
return entries, err
}
func genKey(dirPath, fileName string) (key []byte) {
key = []byte(dirPath)
key = append(key, DIR_FILE_SEPARATOR)
key = append(key, []byte(fileName)...)
return key
}
func genDirectoryKeyPrefix(fullpath filer2.FullPath, startFileName string) (keyPrefix []byte) {
keyPrefix = []byte(string(fullpath))
keyPrefix = append(keyPrefix, DIR_FILE_SEPARATOR)
if len(startFileName) > 0 {
keyPrefix = append(keyPrefix, []byte(startFileName)...)
}
return keyPrefix
}
func getNameFromKey(key []byte) string {
sepIndex := len(key) - 1
for sepIndex >= 0 && key[sepIndex] != DIR_FILE_SEPARATOR {
sepIndex--
}
return string(key[sepIndex+1:])
}