Merge branch 'develop'

cmd/ledis-server/main.go

@@ -9,7 +9,7 @@ import (
 	"syscall"
 )
 
-var configFile = flag.String("config", "", "ledisdb config file")
+var configFile = flag.String("config", "/etc/ledis.json", "ledisdb config file")
 
 func main() {
 	runtime.GOMAXPROCS(runtime.NumCPU())

etc/ledis.json

@@ -1,12 +1,14 @@
 {
     "addr": "127.0.0.1:6380",
+    "data_dir": "/tmp/ledis_server",
     "db": {
         "data_db" : {
-            "path": "/tmp/ledisdb",
             "compression": false,
             "block_size": 32768,
             "write_buffer_size": 67108864,
             "cache_size": 524288000            
         }
-    }
+    },
+
+    "access_log" : "access.log"
 }

ledis/binlog.go

@@ -0,0 +1,329 @@
+package ledis
+
+import (
+	"bufio"
+	"encoding/binary"
+	"encoding/json"
+	"fmt"
+	"github.com/siddontang/go-log/log"
+	"io/ioutil"
+	"os"
+	"path"
+	"strconv"
+	"strings"
+	"time"
+)
+
+const (
+	MaxBinLogFileSize int = 1024 * 1024 * 1024
+	MaxBinLogFileNum  int = 10000
+
+	DefaultBinLogFileSize int = MaxBinLogFileSize
+	DefaultBinLogFileNum  int = 10
+)
+
+/*
+index file format:
+ledis-bin.00001
+ledis-bin.00002
+ledis-bin.00003
+
+log file format
+
+timestamp(bigendian uint32, seconds)|PayloadLen(bigendian uint32)|PayloadData
+
+*/
+
+type BinLogConfig struct {
+	Path        string `json:"path"`
+	MaxFileSize int    `json:"max_file_size"`
+	MaxFileNum  int    `json:"max_file_num"`
+}
+
+func (cfg *BinLogConfig) adjust() {
+	if cfg.MaxFileSize <= 0 {
+		cfg.MaxFileSize = DefaultBinLogFileSize
+	} else if cfg.MaxFileSize > MaxBinLogFileSize {
+		cfg.MaxFileSize = MaxBinLogFileSize
+	}
+
+	if cfg.MaxFileNum <= 0 {
+		cfg.MaxFileNum = DefaultBinLogFileNum
+	} else if cfg.MaxFileNum > MaxBinLogFileNum {
+		cfg.MaxFileNum = MaxBinLogFileNum
+	}
+}
+
+type BinLog struct {
+	cfg *BinLogConfig
+
+	logFile *os.File
+
+	logWb *bufio.Writer
+
+	indexName    string
+	logNames     []string
+	lastLogIndex int64
+}
+
+func NewBinLog(data json.RawMessage) (*BinLog, error) {
+	var cfg BinLogConfig
+
+	if err := json.Unmarshal(data, &cfg); err != nil {
+		return nil, err
+	}
+
+	return NewBinLogWithConfig(&cfg)
+}
+
+func NewBinLogWithConfig(cfg *BinLogConfig) (*BinLog, error) {
+	cfg.adjust()
+
+	l := new(BinLog)
+
+	l.cfg = cfg
+
+	if err := os.MkdirAll(cfg.Path, os.ModePerm); err != nil {
+		return nil, err
+	}
+
+	l.logNames = make([]string, 0, 16)
+
+	if err := l.loadIndex(); err != nil {
+		return nil, err
+	}
+
+	return l, nil
+}
+
+func (l *BinLog) flushIndex() error {
+	data := strings.Join(l.logNames, "\n")
+
+	bakName := fmt.Sprintf("%s.bak", l.indexName)
+	f, err := os.OpenFile(bakName, os.O_WRONLY|os.O_CREATE, 0666)
+	if err != nil {
+		log.Error("create binlog bak index error %s", err.Error())
+		return err
+	}
+
+	if _, err := f.WriteString(data); err != nil {
+		log.Error("write binlog index error %s", err.Error())
+		f.Close()
+		return err
+	}
+
+	f.Close()
+
+	if err := os.Rename(bakName, l.indexName); err != nil {
+		log.Error("rename binlog bak index error %s", err.Error())
+		return err
+	}
+
+	return nil
+}
+
+func (l *BinLog) loadIndex() error {
+	l.indexName = path.Join(l.cfg.Path, fmt.Sprintf("ledis-bin.index"))
+	if _, err := os.Stat(l.indexName); os.IsNotExist(err) {
+		//no index file, nothing to do
+	} else {
+		indexData, err := ioutil.ReadFile(l.indexName)
+		if err != nil {
+			return err
+		}
+
+		lines := strings.Split(string(indexData), "\n")
+		for _, line := range lines {
+			line = strings.Trim(line, "\r\n ")
+			if len(line) == 0 {
+				continue
+			}
+
+			if _, err := os.Stat(path.Join(l.cfg.Path, line)); err != nil {
+				log.Error("load index line %s error %s", line, err.Error())
+				return err
+			} else {
+				l.logNames = append(l.logNames, line)
+			}
+		}
+	}
+	if l.cfg.MaxFileNum > 0 && len(l.logNames) > l.cfg.MaxFileNum {
+		//remove oldest logfile
+		if err := l.Purge(len(l.logNames) - l.cfg.MaxFileNum); err != nil {
+			return err
+		}
+	}
+
+	var err error
+	if len(l.logNames) == 0 {
+		l.lastLogIndex = 1
+	} else {
+		lastName := l.logNames[len(l.logNames)-1]
+
+		if l.lastLogIndex, err = strconv.ParseInt(path.Ext(lastName)[1:], 10, 64); err != nil {
+			log.Error("invalid logfile name %s", err.Error())
+			return err
+		}
+
+		//like mysql, if server restart, a new binlog will create
+		l.lastLogIndex++
+	}
+
+	return nil
+}
+
+func (l *BinLog) getLogFile() string {
+	return l.FormatLogFileName(l.lastLogIndex)
+}
+
+func (l *BinLog) openNewLogFile() error {
+	var err error
+	lastName := l.getLogFile()
+
+	logPath := path.Join(l.cfg.Path, lastName)
+	if l.logFile, err = os.OpenFile(logPath, os.O_CREATE|os.O_WRONLY, 0666); err != nil {
+		log.Error("open new logfile error %s", err.Error())
+		return err
+	}
+
+	if l.cfg.MaxFileNum > 0 && len(l.logNames) == l.cfg.MaxFileNum {
+		l.purge(1)
+	}
+
+	l.logNames = append(l.logNames, lastName)
+
+	if l.logWb == nil {
+		l.logWb = bufio.NewWriterSize(l.logFile, 1024)
+	} else {
+		l.logWb.Reset(l.logFile)
+	}
+
+	if err = l.flushIndex(); err != nil {
+		return err
+	}
+
+	return nil
+}
+
+func (l *BinLog) checkLogFileSize() bool {
+	if l.logFile == nil {
+		return false
+	}
+
+	st, _ := l.logFile.Stat()
+	if st.Size() >= int64(l.cfg.MaxFileSize) {
+		l.lastLogIndex++
+
+		l.logFile.Close()
+		l.logFile = nil
+		return true
+	}
+
+	return false
+}
+
+func (l *BinLog) purge(n int) {
+	for i := 0; i < n; i++ {
+		logPath := path.Join(l.cfg.Path, l.logNames[i])
+		os.Remove(logPath)
+	}
+
+	copy(l.logNames[0:], l.logNames[n:])
+	l.logNames = l.logNames[0 : len(l.logNames)-n]
+}
+
+func (l *BinLog) Close() {
+	if l.logFile != nil {
+		l.logFile.Close()
+		l.logFile = nil
+	}
+}
+
+func (l *BinLog) LogNames() []string {
+	return l.logNames
+}
+
+func (l *BinLog) LogFileName() string {
+	return l.getLogFile()
+}
+
+func (l *BinLog) LogFilePos() int64 {
+	if l.logFile == nil {
+		return 0
+	} else {
+		st, _ := l.logFile.Stat()
+		return st.Size()
+	}
+}
+
+func (l *BinLog) LogFileIndex() int64 {
+	return l.lastLogIndex
+}
+
+func (l *BinLog) FormatLogFileName(index int64) string {
+	return fmt.Sprintf("ledis-bin.%07d", index)
+}
+
+func (l *BinLog) FormatLogFilePath(index int64) string {
+	return path.Join(l.cfg.Path, l.FormatLogFileName(index))
+}
+
+func (l *BinLog) LogPath() string {
+	return l.cfg.Path
+}
+
+func (l *BinLog) Purge(n int) error {
+	if len(l.logNames) == 0 {
+		return nil
+	}
+
+	if n >= len(l.logNames) {
+		n = len(l.logNames)
+		//can not purge current log file
+		if l.logNames[n-1] == l.getLogFile() {
+			n = n - 1
+		}
+	}
+
+	l.purge(n)
+
+	return l.flushIndex()
+}
+
+func (l *BinLog) Log(args ...[]byte) error {
+	var err error
+
+	if l.logFile == nil {
+		if err = l.openNewLogFile(); err != nil {
+			return err
+		}
+	}
+
+	//we treat log many args as a batch, so use same createTime
+	createTime := uint32(time.Now().Unix())
+
+	for _, data := range args {
+		payLoadLen := uint32(len(data))
+
+		if err := binary.Write(l.logWb, binary.BigEndian, createTime); err != nil {
+			return err
+		}
+
+		if err := binary.Write(l.logWb, binary.BigEndian, payLoadLen); err != nil {
+			return err
+		}
+
+		if _, err := l.logWb.Write(data); err != nil {
+			return err
+		}
+	}
+
+	if err = l.logWb.Flush(); err != nil {
+		log.Error("write log error %s", err.Error())
+		return err
+	}
+
+	l.checkLogFileSize()
+
+	return nil
+}

ledis/binlog_test.go

@@ -0,0 +1,36 @@
+package ledis
+
+import (
+	"io/ioutil"
+	"os"
+	"testing"
+)
+
+func TestBinLog(t *testing.T) {
+	cfg := new(BinLogConfig)
+
+	cfg.MaxFileNum = 1
+	cfg.MaxFileSize = 1024
+	cfg.Path = "/tmp/ledis_binlog"
+
+	os.RemoveAll(cfg.Path)
+
+	b, err := NewBinLogWithConfig(cfg)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	if err := b.Log(make([]byte, 1024)); err != nil {
+		t.Fatal(err)
+	}
+
+	if err := b.Log(make([]byte, 1024)); err != nil {
+		t.Fatal(err)
+	}
+
+	if fs, err := ioutil.ReadDir(cfg.Path); err != nil {
+		t.Fatal(err)
+	} else if len(fs) != 2 {
+		t.Fatal(len(fs))
+	}
+}

ledis/binlog_util.go

@@ -0,0 +1,62 @@
+package ledis
+
+import (
+	"encoding/binary"
+	"errors"
+)
+
+var (
+	errBinLogDeleteType  = errors.New("invalid bin log delete type")
+	errBinLogPutType     = errors.New("invalid bin log put type")
+	errBinLogCommandType = errors.New("invalid bin log command type")
+)
+
+func encodeBinLogDelete(key []byte) []byte {
+	buf := make([]byte, 1+len(key))
+	buf[0] = BinLogTypeDeletion
+	copy(buf[1:], key)
+	return buf
+}
+
+func decodeBinLogDelete(sz []byte) ([]byte, error) {
+	if len(sz) < 1 || sz[0] != BinLogTypeDeletion {
+		return nil, errBinLogDeleteType
+	}
+
+	return sz[1:], nil
+}
+
+func encodeBinLogPut(key []byte, value []byte) []byte {
+	buf := make([]byte, 3+len(key)+len(value))
+	buf[0] = BinLogTypePut
+	pos := 1
+	binary.BigEndian.PutUint16(buf[pos:], uint16(len(key)))
+	pos += 2
+	copy(buf[pos:], key)
+	pos += len(key)
+	copy(buf[pos:], value)
+
+	return buf
+}
+
+func decodeBinLogPut(sz []byte) ([]byte, []byte, error) {
+	if len(sz) < 3 || sz[0] != BinLogTypePut {
+		return nil, nil, errBinLogPutType
+	}
+
+	keyLen := int(binary.BigEndian.Uint16(sz[1:]))
+	if 3+keyLen > len(sz) {
+		return nil, nil, errBinLogPutType
+	}
+
+	return sz[3 : 3+keyLen], sz[3+keyLen:], nil
+}
+
+func encodeBinLogCommand(commandType uint8, args ...[]byte) []byte {
+	//to do
+	return nil
+}
+
+func decodeBinLogCommand(sz []byte) (uint8, [][]byte, error) {
+	return 0, nil, errBinLogCommandType
+}

ledis/const.go

@@ -13,24 +13,44 @@ const (
 	zsetType
 	zSizeType
 	zScoreType
+
+	kvExpType
+	kvExpMetaType
+	lExpType
+	lExpMetaType
+	hExpType
+	hExpMetaType
+	zExpType
+	zExpMetaType
 )
 
 const (
 	defaultScanCount int = 10
 )
 
+var (
+	errKeySize        = errors.New("invalid key size")
+	errValueSize      = errors.New("invalid value size")
+	errHashFieldSize  = errors.New("invalid hash field size")
+	errZSetMemberSize = errors.New("invalid zset member size")
+	errExpireValue    = errors.New("invalid expire value")
+)
+
 const (
 	//we don't support too many databases
 	MaxDBNumber uint8 = 16
 
 	//max key size
-	MaxKeySize int = 1<<16 - 1
+	MaxKeySize int = 1024
 
 	//max hash field size
-	MaxHashFieldSize int = 1<<16 - 1
+	MaxHashFieldSize int = 1024
 
 	//max zset member size
-	MaxZSetMemberSize int = 1<<16 - 1
+	MaxZSetMemberSize int = 1024
+
+	//max value size
+	MaxValueSize int = 10 * 1024 * 1024
 )
 
 var (
@@ -39,3 +59,9 @@ var (
 	ErrZSetMemberSize = errors.New("invalid zset member size")
 	ErrScoreMiss      = errors.New("zset score miss")
 )
+
+const (
+	BinLogTypeDeletion uint8 = 0x0
+	BinLogTypePut      uint8 = 0x1
+	BinLogTypeCommand  uint8 = 0x2
+)

ledis/dump.go

@@ -0,0 +1,167 @@
+package ledis
+
+import (
+	"bufio"
+	"bytes"
+	"encoding/binary"
+	"github.com/siddontang/go-leveldb/leveldb"
+	"io"
+	"os"
+)
+
+//dump format
+// fileIndex(bigendian int64)|filePos(bigendian int64)
+// |keylen(bigendian int32)|key|valuelen(bigendian int32)|value......
+
+type MasterInfo struct {
+	LogFileIndex int64
+	LogPos       int64
+}
+
+func (m *MasterInfo) WriteTo(w io.Writer) error {
+	if err := binary.Write(w, binary.BigEndian, m.LogFileIndex); err != nil {
+		return err
+	}
+
+	if err := binary.Write(w, binary.BigEndian, m.LogPos); err != nil {
+		return err
+	}
+	return nil
+}
+
+func (m *MasterInfo) ReadFrom(r io.Reader) error {
+	err := binary.Read(r, binary.BigEndian, &m.LogFileIndex)
+	if err != nil {
+		return err
+	}
+
+	err = binary.Read(r, binary.BigEndian, &m.LogPos)
+	if err != nil {
+		return err
+	}
+
+	return nil
+}
+
+func (l *Ledis) DumpFile(path string) error {
+	f, err := os.Create(path)
+	if err != nil {
+		return err
+	}
+	defer f.Close()
+
+	return l.Dump(f)
+}
+
+func (l *Ledis) Dump(w io.Writer) error {
+	var sp *leveldb.Snapshot
+	var m *MasterInfo = new(MasterInfo)
+	if l.binlog == nil {
+		sp = l.ldb.NewSnapshot()
+	} else {
+		l.Lock()
+		sp = l.ldb.NewSnapshot()
+		m.LogFileIndex = l.binlog.LogFileIndex()
+		m.LogPos = l.binlog.LogFilePos()
+		l.Unlock()
+	}
+
+	var err error
+
+	wb := bufio.NewWriterSize(w, 4096)
+	if err = m.WriteTo(wb); err != nil {
+		return err
+	}
+
+	it := sp.Iterator(nil, nil, leveldb.RangeClose, 0, -1)
+	var key []byte
+	var value []byte
+	for ; it.Valid(); it.Next() {
+		key = it.Key()
+		value = it.Value()
+
+		if err = binary.Write(wb, binary.BigEndian, uint16(len(key))); err != nil {
+			return err
+		}
+
+		if _, err = wb.Write(key); err != nil {
+			return err
+		}
+
+		if err = binary.Write(wb, binary.BigEndian, uint32(len(value))); err != nil {
+			return err
+		}
+
+		if _, err = wb.Write(value); err != nil {
+			return err
+		}
+	}
+
+	if err = wb.Flush(); err != nil {
+		return err
+	}
+
+	return nil
+}
+
+func (l *Ledis) LoadDumpFile(path string) (*MasterInfo, error) {
+	f, err := os.Open(path)
+	if err != nil {
+		return nil, err
+	}
+	defer f.Close()
+
+	return l.LoadDump(f)
+}
+
+func (l *Ledis) LoadDump(r io.Reader) (*MasterInfo, error) {
+	l.Lock()
+	defer l.Unlock()
+
+	info := new(MasterInfo)
+
+	rb := bufio.NewReaderSize(r, 4096)
+
+	err := info.ReadFrom(rb)
+	if err != nil {
+		return nil, err
+	}
+
+	var keyLen uint16
+	var valueLen uint32
+
+	var keyBuf bytes.Buffer
+	var valueBuf bytes.Buffer
+	for {
+		if err = binary.Read(rb, binary.BigEndian, &keyLen); err != nil && err != io.EOF {
+			return nil, err
+		} else if err == io.EOF {
+			break
+		}
+
+		if _, err = io.CopyN(&keyBuf, rb, int64(keyLen)); err != nil {
+			return nil, err
+		}
+
+		if err = binary.Read(rb, binary.BigEndian, &valueLen); err != nil {
+			return nil, err
+		}
+
+		if _, err = io.CopyN(&valueBuf, rb, int64(valueLen)); err != nil {
+			return nil, err
+		}
+
+		if err = l.ldb.Put(keyBuf.Bytes(), valueBuf.Bytes()); err != nil {
+			return nil, err
+		}
+
+		if l.binlog != nil {
+			err = l.binlog.Log(encodeBinLogPut(keyBuf.Bytes(), valueBuf.Bytes()))
+		}
+
+		keyBuf.Reset()
+		valueBuf.Reset()
+	}
+
+	return info, nil
+}

ledis/dump_test.go

@@ -0,0 +1,73 @@
+package ledis
+
+import (
+	"bytes"
+	"github.com/siddontang/go-leveldb/leveldb"
+	"os"
+	"testing"
+)
+
+func TestDump(t *testing.T) {
+	os.RemoveAll("/tmp/test_ledis_master")
+	os.RemoveAll("/tmp/test_ledis_slave")
+
+	var masterConfig = []byte(`
+    {
+        "data_dir" : "/tmp/test_ledis_master",
+        "data_db" : {
+            "compression":true,
+            "block_size" : 32768,
+            "write_buffer_size" : 2097152,
+            "cache_size" : 20971520
+        }
+    }
+    `)
+
+	master, err := Open(masterConfig)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	var slaveConfig = []byte(`
+    {
+        "data_dir" : "/tmp/test_ledis_slave",
+        "data_db" : {
+            "compression":true,
+            "block_size" : 32768,
+            "write_buffer_size" : 2097152,
+            "cache_size" : 20971520
+        }
+    }
+    `)
+
+	var slave *Ledis
+	if slave, err = Open(slaveConfig); err != nil {
+		t.Fatal(err)
+	}
+
+	db, _ := master.Select(0)
+
+	db.Set([]byte("a"), []byte("1"))
+	db.Set([]byte("b"), []byte("2"))
+	db.Set([]byte("c"), []byte("3"))
+
+	if err := master.DumpFile("/tmp/testdb.dump"); err != nil {
+		t.Fatal(err)
+	}
+
+	if _, err := slave.LoadDumpFile("/tmp/testdb.dump"); err != nil {
+		t.Fatal(err)
+	}
+
+	it := master.ldb.Iterator(nil, nil, leveldb.RangeClose, 0, -1)
+	for ; it.Valid(); it.Next() {
+		key := it.Key()
+		value := it.Value()
+
+		if v, err := slave.ldb.Get(key); err != nil {
+			t.Fatal(err)
+		} else if !bytes.Equal(v, value) {
+			t.Fatal("load dump error")
+		}
+	}
+}

ledis/ledis.go

@@ -4,13 +4,27 @@ import (
 	"encoding/json"
 	"fmt"
 	"github.com/siddontang/go-leveldb/leveldb"
+	"github.com/siddontang/go-log/log"
+	"path"
+	"sync"
+	"time"
 )
 
 type Config struct {
+	DataDir string `json:"data_dir"`
+
+	//if you not set leveldb path, use data_dir/data
 	DataDB leveldb.Config `json:"data_db"`
+
+	UseBinLog bool `json:"use_bin_log"`
+
+	//if you not set bin log path, use data_dir/bin_log
+	BinLog BinLogConfig `json:"bin_log"`
 }
 
 type DB struct {
+	l *Ledis
+
 	db *leveldb.DB
 
 	index uint8
@@ -22,10 +36,16 @@ type DB struct {
 }
 
 type Ledis struct {
+	sync.Mutex
+
 	cfg *Config
 
 	ldb *leveldb.DB
 	dbs [MaxDBNumber]*DB
+
+	binlog *BinLog
+
+	quit chan struct{}
 }
 
 func Open(configJson json.RawMessage) (*Ledis, error) {
@@ -39,38 +59,72 @@ func Open(configJson json.RawMessage) (*Ledis, error) {
 }
 
 func OpenWithConfig(cfg *Config) (*Ledis, error) {
+	if len(cfg.DataDir) == 0 {
+		return nil, fmt.Errorf("must set correct data_dir")
+	}
+
+	if len(cfg.DataDB.Path) == 0 {
+		cfg.DataDB.Path = path.Join(cfg.DataDir, "data")
+	}
+
 	ldb, err := leveldb.OpenWithConfig(&cfg.DataDB)
 	if err != nil {
 		return nil, err
 	}
 
 	l := new(Ledis)
+
+	l.quit = make(chan struct{})
+
 	l.ldb = ldb
 
+	if cfg.UseBinLog {
+		if len(cfg.BinLog.Path) == 0 {
+			cfg.BinLog.Path = path.Join(cfg.DataDir, "bin_log")
+		}
+		l.binlog, err = NewBinLogWithConfig(&cfg.BinLog)
+		if err != nil {
+			return nil, err
+		}
+	} else {
+		l.binlog = nil
+	}
+
 	for i := uint8(0); i < MaxDBNumber; i++ {
 		l.dbs[i] = newDB(l, i)
 	}
 
+	l.activeExpireCycle()
+
 	return l, nil
 }
 
 func newDB(l *Ledis, index uint8) *DB {
 	d := new(DB)
 
+	d.l = l
+
 	d.db = l.ldb
 
 	d.index = index
 
-	d.kvTx = &tx{wb: d.db.NewWriteBatch()}
+	d.kvTx = newTx(l)
-	d.listTx = &tx{wb: d.db.NewWriteBatch()}
+	d.listTx = newTx(l)
-	d.hashTx = &tx{wb: d.db.NewWriteBatch()}
+	d.hashTx = newTx(l)
-	d.zsetTx = &tx{wb: d.db.NewWriteBatch()}
+	d.zsetTx = newTx(l)
 
 	return d
 }
 
 func (l *Ledis) Close() {
+	close(l.quit)
+
 	l.ldb.Close()
+
+	if l.binlog != nil {
+		l.binlog.Close()
+		l.binlog = nil
+	}
 }
 
 func (l *Ledis) Select(index int) (*DB, error) {
@@ -80,3 +134,41 @@ func (l *Ledis) Select(index int) (*DB, error) {
 
 	return l.dbs[index], nil
 }
+
+func (l *Ledis) FlushAll() error {
+	for index, db := range l.dbs {
+		if _, err := db.FlushAll(); err != nil {
+			log.Error("flush db %d error %s", index, err.Error())
+		}
+	}
+
+	return nil
+}
+
+//very dangerous to use
+func (l *Ledis) DataDB() *leveldb.DB {
+	return l.ldb
+}
+
+func (l *Ledis) activeExpireCycle() {
+	var executors []*elimination = make([]*elimination, len(l.dbs))
+	for i, db := range l.dbs {
+		executors[i] = db.newEliminator()
+	}
+
+	go func() {
+		tick := time.NewTicker(1 * time.Second)
+		for {
+			select {
+			case <-tick.C:
+				for _, eli := range executors {
+					eli.active()
+				}
+			case <-l.quit:
+				break
+			}
+		}
+
+		tick.Stop()
+	}()
+}

ledis/ledis_db.go

@@ -1,11 +1,11 @@
 package ledis
 
-func (db *DB) Flush() (drop int64, err error) {
+func (db *DB) FlushAll() (drop int64, err error) {
 	all := [...](func() (int64, error)){
-		db.KvFlush,
+		db.flush,
-		db.LFlush,
+		db.lFlush,
-		db.HFlush,
+		db.hFlush,
-		db.ZFlush}
+		db.zFlush}
 
 	for _, flush := range all {
 		if n, e := flush(); e != nil {
@@ -15,5 +15,16 @@ func (db *DB) Flush() (drop int64, err error) {
 			drop += n
 		}
 	}
+
 	return
 }
+
+func (db *DB) newEliminator() *elimination {
+	eliminator := newEliminator(db)
+	eliminator.regRetireContext(kvExpType, db.kvTx, db.delete)
+	eliminator.regRetireContext(lExpType, db.listTx, db.lDelete)
+	eliminator.regRetireContext(hExpType, db.hashTx, db.hDelete)
+	eliminator.regRetireContext(zExpType, db.zsetTx, db.zDelete)
+
+	return eliminator
+}

ledis/ledis_test.go

@@ -1,6 +1,7 @@
 package ledis
 
 import (
+	"os"
 	"sync"
 	"testing"
 )
@@ -12,23 +13,29 @@ func getTestDB() *DB {
 	f := func() {
 		var d = []byte(`
             {
+            	"data_dir" : "/tmp/test_ledis",
                 "data_db" : {
-                    "path" : "/tmp/testdb",
                     "compression":true,
                     "block_size" : 32768,
                     "write_buffer_size" : 2097152,
                     "cache_size" : 20971520
+                },
+
+                "binlog" : {
+                	"max_file_size" : 1073741824,
+                	"max_file_num" : 3
                 }	
             }
             `)
+
+		os.RemoveAll("/tmp/test_ledis")
+
 		var err error
 		testLedis, err = Open(d)
 		if err != nil {
 			println(err.Error())
 			panic(err)
 		}
-
-		testLedis.ldb.Clear()
 	}
 
 	testLedisOnce.Do(f)
@@ -75,7 +82,7 @@ func TestFlush(t *testing.T) {
 	db1.LPush([]byte("lst"), []byte("a1"), []byte("b2"))
 	db1.ZAdd([]byte("zset_0"), ScorePair{int64(3), []byte("mc")})
 
-	db1.Flush()
+	db1.FlushAll()
 
 	//	0 - existing
 	if exists, _ := db0.Exists([]byte("a")); exists <= 0 {

ledis/replication.go

@@ -0,0 +1,238 @@
+package ledis
+
+import (
+	"bufio"
+	"bytes"
+	"encoding/binary"
+	"errors"
+	"github.com/siddontang/go-log/log"
+	"io"
+	"os"
+)
+
+var (
+	errInvalidBinLogEvent = errors.New("invalid binglog event")
+	errInvalidBinLogFile  = errors.New("invalid binlog file")
+)
+
+func (l *Ledis) ReplicateEvent(event []byte) error {
+	if len(event) == 0 {
+		return errInvalidBinLogEvent
+	}
+
+	logType := uint8(event[0])
+	switch logType {
+	case BinLogTypePut:
+		return l.replicatePutEvent(event)
+	case BinLogTypeDeletion:
+		return l.replicateDeleteEvent(event)
+	case BinLogTypeCommand:
+		return l.replicateCommandEvent(event)
+	default:
+		return errInvalidBinLogEvent
+	}
+}
+
+func (l *Ledis) replicatePutEvent(event []byte) error {
+	key, value, err := decodeBinLogPut(event)
+	if err != nil {
+		return err
+	}
+
+	if err = l.ldb.Put(key, value); err != nil {
+		return err
+	}
+
+	if l.binlog != nil {
+		err = l.binlog.Log(event)
+	}
+
+	return err
+}
+
+func (l *Ledis) replicateDeleteEvent(event []byte) error {
+	key, err := decodeBinLogDelete(event)
+	if err != nil {
+		return err
+	}
+
+	if err = l.ldb.Delete(key); err != nil {
+		return err
+	}
+
+	if l.binlog != nil {
+		err = l.binlog.Log(event)
+	}
+
+	return err
+}
+
+func (l *Ledis) replicateCommandEvent(event []byte) error {
+	return errors.New("command event not supported now")
+}
+
+func (l *Ledis) ReplicateFromReader(rb io.Reader) error {
+	var createTime uint32
+	var dataLen uint32
+	var dataBuf bytes.Buffer
+	var err error
+
+	for {
+		if err = binary.Read(rb, binary.BigEndian, &createTime); err != nil {
+			if err == io.EOF {
+				break
+			} else {
+				return err
+			}
+		}
+
+		if err = binary.Read(rb, binary.BigEndian, &dataLen); err != nil {
+			return err
+		}
+
+		if _, err = io.CopyN(&dataBuf, rb, int64(dataLen)); err != nil {
+			return err
+		}
+
+		err = l.ReplicateEvent(dataBuf.Bytes())
+		if err != nil {
+			log.Fatal("replication error %s, skip to next", err.Error())
+		}
+
+		dataBuf.Reset()
+	}
+
+	return nil
+}
+
+func (l *Ledis) ReplicateFromData(data []byte) error {
+	rb := bytes.NewReader(data)
+
+	l.Lock()
+	err := l.ReplicateFromReader(rb)
+	l.Unlock()
+
+	return err
+}
+
+func (l *Ledis) ReplicateFromBinLog(filePath string) error {
+	f, err := os.Open(filePath)
+	if err != nil {
+		return err
+	}
+
+	rb := bufio.NewReaderSize(f, 4096)
+
+	l.Lock()
+	err = l.ReplicateFromReader(rb)
+	l.Unlock()
+
+	f.Close()
+
+	return err
+}
+
+const maxSyncEvents = 64
+
+func (l *Ledis) ReadEventsTo(info *MasterInfo, w io.Writer) (n int, err error) {
+	n = 0
+	if l.binlog == nil {
+		//binlog not supported
+		info.LogFileIndex = 0
+		info.LogPos = 0
+		return
+	}
+
+	index := info.LogFileIndex
+	offset := info.LogPos
+
+	filePath := l.binlog.FormatLogFilePath(index)
+
+	var f *os.File
+	f, err = os.Open(filePath)
+	if os.IsNotExist(err) {
+		lastIndex := l.binlog.LogFileIndex()
+
+		if index == lastIndex {
+			//no binlog at all
+			info.LogPos = 0
+		} else {
+			//slave binlog info had lost
+			info.LogFileIndex = -1
+		}
+	}
+
+	if err != nil {
+		if os.IsNotExist(err) {
+			err = nil
+		}
+		return
+	}
+
+	defer f.Close()
+
+	var fileSize int64
+	st, _ := f.Stat()
+	fileSize = st.Size()
+
+	if fileSize == info.LogPos {
+		return
+	}
+
+	if _, err = f.Seek(offset, os.SEEK_SET); err != nil {
+		//may be invliad seek offset
+		return
+	}
+
+	var lastCreateTime uint32 = 0
+	var createTime uint32
+	var dataLen uint32
+
+	var eventsNum int = 0
+
+	for {
+		if err = binary.Read(f, binary.BigEndian, &createTime); err != nil {
+			if err == io.EOF {
+				//we will try to use next binlog
+				if index < l.binlog.LogFileIndex() {
+					info.LogFileIndex += 1
+					info.LogPos = 0
+				}
+				err = nil
+				return
+			} else {
+				return
+			}
+		}
+
+		eventsNum++
+		if lastCreateTime == 0 {
+			lastCreateTime = createTime
+		} else if lastCreateTime != createTime {
+			return
+		} else if eventsNum > maxSyncEvents {
+			return
+		}
+
+		if err = binary.Read(f, binary.BigEndian, &dataLen); err != nil {
+			return
+		}
+
+		if err = binary.Write(w, binary.BigEndian, createTime); err != nil {
+			return
+		}
+
+		if err = binary.Write(w, binary.BigEndian, dataLen); err != nil {
+			return
+		}
+
+		if _, err = io.CopyN(w, f, int64(dataLen)); err != nil {
+			return
+		}
+
+		n += (8 + int(dataLen))
+		info.LogPos = info.LogPos + 8 + int64(dataLen)
+	}
+
+	return
+}

ledis/replication_test.go

@@ -0,0 +1,117 @@
+package ledis
+
+import (
+	"bytes"
+	"fmt"
+	"github.com/siddontang/go-leveldb/leveldb"
+	"os"
+	"path"
+	"testing"
+)
+
+func checkLedisEqual(master *Ledis, slave *Ledis) error {
+	it := master.ldb.Iterator(nil, nil, leveldb.RangeClose, 0, -1)
+	for ; it.Valid(); it.Next() {
+		key := it.Key()
+		value := it.Value()
+
+		if v, err := slave.ldb.Get(key); err != nil {
+			return err
+		} else if !bytes.Equal(v, value) {
+			return fmt.Errorf("replication error %d != %d", len(v), len(value))
+		}
+	}
+
+	return nil
+}
+
+func TestReplication(t *testing.T) {
+	var master *Ledis
+	var slave *Ledis
+	var err error
+
+	os.RemoveAll("/tmp/test_repl")
+
+	master, err = Open([]byte(`
+        {
+            "data_dir" : "/tmp/test_repl/master",
+            "use_bin_log" : true,
+            "bin_log" : {
+                "max_file_size" : 50
+            }
+        } 
+        `))
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	slave, err = Open([]byte(`
+        {
+            "data_dir" : "/tmp/test_repl/slave"
+        }
+        `))
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	db, _ := master.Select(0)
+	db.Set([]byte("a"), []byte("value"))
+	db.Set([]byte("b"), []byte("value"))
+	db.Set([]byte("c"), []byte("value"))
+
+	db.HSet([]byte("a"), []byte("1"), []byte("value"))
+	db.HSet([]byte("b"), []byte("2"), []byte("value"))
+	db.HSet([]byte("c"), []byte("3"), []byte("value"))
+
+	for _, name := range master.binlog.LogNames() {
+		p := path.Join(master.binlog.cfg.Path, name)
+
+		err = slave.ReplicateFromBinLog(p)
+		if err != nil {
+			t.Fatal(err)
+		}
+	}
+
+	if err = checkLedisEqual(master, slave); err != nil {
+		t.Fatal(err)
+	}
+
+	slave.FlushAll()
+
+	db.Set([]byte("a1"), []byte("1"))
+	db.Set([]byte("b1"), []byte("2"))
+	db.Set([]byte("c1"), []byte("3"))
+
+	db.HSet([]byte("a1"), []byte("1"), []byte("value"))
+	db.HSet([]byte("b1"), []byte("2"), []byte("value"))
+	db.HSet([]byte("c1"), []byte("3"), []byte("value"))
+
+	info := new(MasterInfo)
+	info.LogFileIndex = 1
+	info.LogPos = 0
+	var buf bytes.Buffer
+	var n int
+
+	for {
+		buf.Reset()
+		n, err = master.ReadEventsTo(info, &buf)
+		if err != nil {
+			t.Fatal(err)
+		} else if info.LogFileIndex == -1 {
+			t.Fatal("invalid log file index -1")
+		} else if info.LogFileIndex == 0 {
+			t.Fatal("invalid log file index 0")
+		} else {
+			if err = slave.ReplicateFromReader(&buf); err != nil {
+				t.Fatal(err)
+			}
+			if n == 0 {
+				break
+			}
+		}
+	}
+
+	if err = checkLedisEqual(master, slave); err != nil {
+		t.Fatal(err)
+	}
+}

ledis/t_hash.go

@@ -4,6 +4,7 @@ import (
 	"encoding/binary"
 	"errors"
 	"github.com/siddontang/go-leveldb/leveldb"
+	"time"
 )
 
 type FVPair struct {
@@ -21,9 +22,9 @@ const (
 
 func checkHashKFSize(key []byte, field []byte) error {
 	if len(key) > MaxKeySize || len(key) == 0 {
-		return ErrKeySize
+		return errKeySize
 	} else if len(field) > MaxHashFieldSize || len(field) == 0 {
-		return ErrHashFieldSize
+		return errHashFieldSize
 	}
 	return nil
 }
@@ -105,10 +106,6 @@ func (db *DB) hEncodeStopKey(key []byte) []byte {
 	return k
 }
 
-func (db *DB) HLen(key []byte) (int64, error) {
-	return Int64(db.db.Get(db.hEncodeSizeKey(key)))
-}
-
 func (db *DB) hSetItem(key []byte, field []byte, value []byte) (int64, error) {
 	t := db.hashTx
 
@@ -127,9 +124,54 @@ func (db *DB) hSetItem(key []byte, field []byte, value []byte) (int64, error) {
 	return n, nil
 }
 
+//	ps : here just focus on deleting the hash data,
+//		 any other likes expire is ignore.
+func (db *DB) hDelete(t *tx, key []byte) int64 {
+	sk := db.hEncodeSizeKey(key)
+	start := db.hEncodeStartKey(key)
+	stop := db.hEncodeStopKey(key)
+
+	var num int64 = 0
+	it := db.db.Iterator(start, stop, leveldb.RangeROpen, 0, -1)
+	for ; it.Valid(); it.Next() {
+		t.Delete(it.Key())
+		num++
+	}
+	it.Close()
+
+	t.Delete(sk)
+	return num
+}
+
+func (db *DB) hExpireAt(key []byte, when int64) (int64, error) {
+	t := db.hashTx
+	t.Lock()
+	defer t.Unlock()
+
+	if hlen, err := db.HLen(key); err != nil || hlen == 0 {
+		return 0, err
+	} else {
+		db.expireAt(t, hExpType, key, when)
+		if err := t.Commit(); err != nil {
+			return 0, err
+		}
+	}
+	return 1, nil
+}
+
+func (db *DB) HLen(key []byte) (int64, error) {
+	if err := checkKeySize(key); err != nil {
+		return 0, err
+	}
+
+	return Int64(db.db.Get(db.hEncodeSizeKey(key)))
+}
+
 func (db *DB) HSet(key []byte, field []byte, value []byte) (int64, error) {
 	if err := checkHashKFSize(key, field); err != nil {
 		return 0, err
+	} else if err := checkValueSize(value); err != nil {
+		return 0, err
 	}
 
 	t := db.hashTx
@@ -166,6 +208,8 @@ func (db *DB) HMset(key []byte, args ...FVPair) error {
 	for i := 0; i < len(args); i++ {
 		if err := checkHashKFSize(key, args[i].Field); err != nil {
 			return err
+		} else if err := checkValueSize(args[i].Value); err != nil {
+			return err
 		}
 
 		ek = db.hEncodeHashKey(key, args[i].Field)
@@ -261,6 +305,7 @@ func (db *DB) hIncrSize(key []byte, delta int64) (int64, error) {
 		if size <= 0 {
 			size = 0
 			t.Delete(sk)
+			db.rmExpire(t, hExpType, key)
 		} else {
 			t.Put(sk, PutInt64(size))
 		}
@@ -374,30 +419,18 @@ func (db *DB) HClear(key []byte) (int64, error) {
 		return 0, err
 	}
 
-	sk := db.hEncodeSizeKey(key)
-	start := db.hEncodeStartKey(key)
-	stop := db.hEncodeStopKey(key)
-
 	t := db.hashTx
 	t.Lock()
 	defer t.Unlock()
 
-	var num int64 = 0
+	num := db.hDelete(t, key)
-	it := db.db.Iterator(start, stop, leveldb.RangeROpen, 0, -1)
+	db.rmExpire(t, hExpType, key)
-	for ; it.Valid(); it.Next() {
-		t.Delete(it.Key())
-		num++
-	}
-
-	it.Close()
-
-	t.Delete(sk)
 
 	err := t.Commit()
 	return num, err
 }
 
-func (db *DB) HFlush() (drop int64, err error) {
+func (db *DB) hFlush() (drop int64, err error) {
 	t := db.kvTx
 	t.Lock()
 	defer t.Unlock()
@@ -414,7 +447,15 @@ func (db *DB) HFlush() (drop int64, err error) {
 	for ; it.Valid(); it.Next() {
 		t.Delete(it.Key())
 		drop++
+		if drop&1023 == 0 {
+			if err = t.Commit(); err != nil {
+				return
+			}
+		}
 	}
+	it.Close()
+
+	db.expFlush(t, hExpType)
 
 	err = t.Commit()
 	return
@@ -452,6 +493,31 @@ func (db *DB) HScan(key []byte, field []byte, count int, inclusive bool) ([]FVPa
 			v = append(v, FVPair{Field: f, Value: it.Value()})
 		}
 	}
+	it.Close()
 
 	return v, nil
 }
+
+func (db *DB) HExpire(key []byte, duration int64) (int64, error) {
+	if duration <= 0 {
+		return 0, errExpireValue
+	}
+
+	return db.hExpireAt(key, time.Now().Unix()+duration)
+}
+
+func (db *DB) HExpireAt(key []byte, when int64) (int64, error) {
+	if when <= time.Now().Unix() {
+		return 0, errExpireValue
+	}
+
+	return db.hExpireAt(key, when)
+}
+
+func (db *DB) HTTL(key []byte) (int64, error) {
+	if err := checkKeySize(key); err != nil {
+		return -1, err
+	}
+
+	return db.ttl(hExpType, key)
+}

ledis/t_hash_test.go

@@ -42,7 +42,7 @@ func TestDBHash(t *testing.T) {
 func TestDBHScan(t *testing.T) {
 	db := getTestDB()
 
-	db.HFlush()
+	db.hFlush()
 
 	key := []byte("a")
 	db.HSet(key, []byte("1"), []byte{})

ledis/t_kv.go

@@ -3,6 +3,7 @@ package ledis
 import (
 	"errors"
 	"github.com/siddontang/go-leveldb/leveldb"
+	"time"
 )
 
 type KVPair struct {
@@ -14,11 +15,19 @@ var errKVKey = errors.New("invalid encode kv key")
 
 func checkKeySize(key []byte) error {
 	if len(key) > MaxKeySize || len(key) == 0 {
-		return ErrKeySize
+		return errKeySize
 	}
 	return nil
 }
 
+func checkValueSize(value []byte) error {
+	if len(value) > MaxValueSize {
+		return errValueSize
+	}
+
+	return nil
+}
+
 func (db *DB) encodeKVKey(key []byte) []byte {
 	ek := make([]byte, len(key)+2)
 	ek[0] = db.index
@@ -75,6 +84,30 @@ func (db *DB) incr(key []byte, delta int64) (int64, error) {
 	return n, err
 }
 
+//	ps : here just focus on deleting the key-value data,
+//		 any other likes expire is ignore.
+func (db *DB) delete(t *tx, key []byte) int64 {
+	key = db.encodeKVKey(key)
+	t.Delete(key)
+	return 1
+}
+
+func (db *DB) setExpireAt(key []byte, when int64) (int64, error) {
+	t := db.kvTx
+	t.Lock()
+	defer t.Unlock()
+
+	if exist, err := db.Exists(key); err != nil || exist == 0 {
+		return 0, err
+	} else {
+		db.expireAt(t, kvExpType, key, when)
+		if err := t.Commit(); err != nil {
+			return 0, err
+		}
+	}
+	return 1, nil
+}
+
 func (db *DB) Decr(key []byte) (int64, error) {
 	return db.incr(key, -1)
 }
@@ -88,22 +121,21 @@ func (db *DB) Del(keys ...[]byte) (int64, error) {
 		return 0, nil
 	}
 
-	var err error
+	codedKeys := make([][]byte, len(keys))
-	for i := range keys {
+	for i, k := range keys {
-		keys[i] = db.encodeKVKey(keys[i])
+		codedKeys[i] = db.encodeKVKey(k)
 	}
 
 	t := db.kvTx
-
 	t.Lock()
 	defer t.Unlock()
 
-	for i := range keys {
+	for i, k := range keys {
-		t.Delete(keys[i])
+		t.Delete(codedKeys[i])
-		//todo binlog
+		db.rmExpire(t, kvExpType, k)
 	}
 
-	err = t.Commit()
+	err := t.Commit()
 	return int64(len(keys)), err
 }
 
@@ -137,6 +169,8 @@ func (db *DB) Get(key []byte) ([]byte, error) {
 func (db *DB) GetSet(key []byte, value []byte) ([]byte, error) {
 	if err := checkKeySize(key); err != nil {
 		return nil, err
+	} else if err := checkValueSize(value); err != nil {
+		return nil, err
 	}
 
 	key = db.encodeKVKey(key)
@@ -204,6 +238,8 @@ func (db *DB) MSet(args ...KVPair) error {
 	for i := 0; i < len(args); i++ {
 		if err := checkKeySize(args[i].Key); err != nil {
 			return err
+		} else if err := checkValueSize(args[i].Value); err != nil {
+			return err
 		}
 
 		key = db.encodeKVKey(args[i].Key)
@@ -222,6 +258,8 @@ func (db *DB) MSet(args ...KVPair) error {
 func (db *DB) Set(key []byte, value []byte) error {
 	if err := checkKeySize(key); err != nil {
 		return err
+	} else if err := checkValueSize(value); err != nil {
+		return err
 	}
 
 	var err error
@@ -244,6 +282,8 @@ func (db *DB) Set(key []byte, value []byte) error {
 func (db *DB) SetNX(key []byte, value []byte) (int64, error) {
 	if err := checkKeySize(key); err != nil {
 		return 0, err
+	} else if err := checkValueSize(value); err != nil {
+		return 0, err
 	}
 
 	var err error
@@ -271,7 +311,7 @@ func (db *DB) SetNX(key []byte, value []byte) (int64, error) {
 	return n, err
 }
 
-func (db *DB) KvFlush() (drop int64, err error) {
+func (db *DB) flush() (drop int64, err error) {
 	t := db.kvTx
 	t.Lock()
 	defer t.Unlock()
@@ -283,9 +323,17 @@ func (db *DB) KvFlush() (drop int64, err error) {
 	for ; it.Valid(); it.Next() {
 		t.Delete(it.Key())
 		drop++
+
+		if drop&1023 == 0 {
+			if err = t.Commit(); err != nil {
+				return
+			}
+		}
 	}
+	it.Close()
 
 	err = t.Commit()
+	err = db.expFlush(t, kvExpType)
 	return
 }
 
@@ -322,6 +370,31 @@ func (db *DB) Scan(key []byte, count int, inclusive bool) ([]KVPair, error) {
 			v = append(v, KVPair{Key: key, Value: it.Value()})
 		}
 	}
+	it.Close()
 
 	return v, nil
 }
+
+func (db *DB) Expire(key []byte, duration int64) (int64, error) {
+	if duration <= 0 {
+		return 0, errExpireValue
+	}
+
+	return db.setExpireAt(key, time.Now().Unix()+duration)
+}
+
+func (db *DB) ExpireAt(key []byte, when int64) (int64, error) {
+	if when <= time.Now().Unix() {
+		return 0, errExpireValue
+	}
+
+	return db.setExpireAt(key, when)
+}
+
+func (db *DB) TTL(key []byte) (int64, error) {
+	if err := checkKeySize(key); err != nil {
+		return -1, err
+	}
+
+	return db.ttl(kvExpType, key)
+}

ledis/t_kv_test.go

@@ -29,7 +29,7 @@ func TestDBKV(t *testing.T) {
 func TestDBScan(t *testing.T) {
 	db := getTestDB()
 
-	db.Flush()
+	db.FlushAll()
 
 	if v, err := db.Scan(nil, 10, true); err != nil {
 		t.Fatal(err)

ledis/t_list.go

@@ -4,6 +4,7 @@ import (
 	"encoding/binary"
 	"errors"
 	"github.com/siddontang/go-leveldb/leveldb"
+	"time"
 )
 
 const (
@@ -84,62 +85,53 @@ func (db *DB) lpush(key []byte, whereSeq int32, args ...[]byte) (int64, error) {
 	var err error
 
 	metaKey := db.lEncodeMetaKey(key)
+	headSeq, tailSeq, size, err = db.lGetMeta(metaKey)
+	if err != nil {
+		return 0, err
+	}
 
-	if len(args) == 0 {
+	var pushCnt int = len(args)
-		_, _, size, err := db.lGetMeta(metaKey)
+	if pushCnt == 0 {
-		return int64(size), err
+		return int64(size), nil
+	}
+
+	var seq int32 = headSeq
+	var delta int32 = -1
+	if whereSeq == listTailSeq {
+		seq = tailSeq
+		delta = 1
 	}
 
 	t := db.listTx
 	t.Lock()
 	defer t.Unlock()
 
-	if headSeq, tailSeq, size, err = db.lGetMeta(metaKey); err != nil {
+	//	append elements
-		return 0, err
+	if size > 0 {
-	}
-
-	var delta int32 = 1
-	var seq int32 = 0
-	if whereSeq == listHeadSeq {
-		delta = -1
-		seq = headSeq
-	} else {
-		seq = tailSeq
-	}
-
-	if size == 0 {
-		headSeq = listInitialSeq
-		tailSeq = listInitialSeq
-		seq = headSeq
-	} else {
 		seq += delta
 	}
 
-	for i := 0; i < len(args); i++ {
+	for i := 0; i < pushCnt; i++ {
 		ek := db.lEncodeListKey(key, seq+int32(i)*delta)
 		t.Put(ek, args[i])
-		//to do add binlog
 	}
 
-	seq += int32(len(args)-1) * delta
+	seq += int32(pushCnt-1) * delta
-
 	if seq <= listMinSeq || seq >= listMaxSeq {
 		return 0, errListSeq
 	}
 
-	size += int32(len(args))
+	//	set meta info
-
 	if whereSeq == listHeadSeq {
 		headSeq = seq
 	} else {
 		tailSeq = seq
 	}
 
-	db.lSetMeta(metaKey, headSeq, tailSeq, size)
+	db.lSetMeta(metaKey, headSeq, tailSeq)
 
 	err = t.Commit()
-
+	return int64(size) + int64(pushCnt), err
-	return int64(size), err
 }
 
 func (db *DB) lpop(key []byte, whereSeq int32) ([]byte, error) {
@@ -153,54 +145,73 @@ func (db *DB) lpop(key []byte, whereSeq int32) ([]byte, error) {
 
 	var headSeq int32
 	var tailSeq int32
-	var size int32
 	var err error
 
 	metaKey := db.lEncodeMetaKey(key)
-
+	headSeq, tailSeq, _, err = db.lGetMeta(metaKey)
-	headSeq, tailSeq, size, err = db.lGetMeta(metaKey)
-
 	if err != nil {
 		return nil, err
 	}
 
-	var seq int32 = 0
+	var value []byte
-	var delta int32 = 1
+
-	if whereSeq == listHeadSeq {
+	var seq int32 = headSeq
-		seq = headSeq
+	if whereSeq == listTailSeq {
-	} else {
-		delta = -1
 		seq = tailSeq
 	}
 
 	itemKey := db.lEncodeListKey(key, seq)
-	var value []byte
 	value, err = db.db.Get(itemKey)
 	if err != nil {
 		return nil, err
 	}
 
-	t.Delete(itemKey)
+	if whereSeq == listHeadSeq {
-	seq += delta
+		headSeq += 1
-
-	size--
-	if size <= 0 {
-		t.Delete(metaKey)
 	} else {
-		if whereSeq == listHeadSeq {
+		tailSeq -= 1
-			headSeq = seq
+	}
-		} else {
+
-			tailSeq = seq
+	t.Delete(itemKey)
-		}
+	size := db.lSetMeta(metaKey, headSeq, tailSeq)
-
+	if size == 0 {
-		db.lSetMeta(metaKey, headSeq, tailSeq, size)
+		db.rmExpire(t, hExpType, key)
 	}
 
-	//todo add binlog
 	err = t.Commit()
 	return value, err
 }
 
+//	ps : here just focus on deleting the list data,
+//		 any other likes expire is ignore.
+func (db *DB) lDelete(t *tx, key []byte) int64 {
+	mk := db.lEncodeMetaKey(key)
+
+	var headSeq int32
+	var tailSeq int32
+	var err error
+
+	headSeq, tailSeq, _, err = db.lGetMeta(mk)
+	if err != nil {
+		return 0
+	}
+
+	var num int64 = 0
+	startKey := db.lEncodeListKey(key, headSeq)
+	stopKey := db.lEncodeListKey(key, tailSeq)
+
+	it := db.db.Iterator(startKey, stopKey, leveldb.RangeClose, 0, -1)
+	for ; it.Valid(); it.Next() {
+		t.Delete(it.Key())
+		num++
+	}
+	it.Close()
+
+	t.Delete(mk)
+
+	return num
+}
+
 func (db *DB) lGetSeq(key []byte, whereSeq int32) (int64, error) {
 	ek := db.lEncodeListKey(key, whereSeq)
 
@@ -213,26 +224,52 @@ func (db *DB) lGetMeta(ek []byte) (headSeq int32, tailSeq int32, size int32, err
 	if err != nil {
 		return
 	} else if v == nil {
+		headSeq = listInitialSeq
+		tailSeq = listInitialSeq
 		size = 0
 		return
 	} else {
 		headSeq = int32(binary.LittleEndian.Uint32(v[0:4]))
 		tailSeq = int32(binary.LittleEndian.Uint32(v[4:8]))
-		size = int32(binary.LittleEndian.Uint32(v[8:]))
+		size = tailSeq - headSeq + 1
 	}
 	return
 }
 
-func (db *DB) lSetMeta(ek []byte, headSeq int32, tailSeq int32, size int32) {
+func (db *DB) lSetMeta(ek []byte, headSeq int32, tailSeq int32) int32 {
 	t := db.listTx
 
-	buf := make([]byte, 12)
+	var size int32 = tailSeq - headSeq + 1
+	if size < 0 {
+		//	todo : log error + panic
+	} else if size == 0 {
+		t.Delete(ek)
+	} else {
+		buf := make([]byte, 8)
 
-	binary.LittleEndian.PutUint32(buf[0:4], uint32(headSeq))
+		binary.LittleEndian.PutUint32(buf[0:4], uint32(headSeq))
-	binary.LittleEndian.PutUint32(buf[4:8], uint32(tailSeq))
+		binary.LittleEndian.PutUint32(buf[4:8], uint32(tailSeq))
-	binary.LittleEndian.PutUint32(buf[8:], uint32(size))
 
-	t.Put(ek, buf)
+		t.Put(ek, buf)
+	}
+
+	return size
+}
+
+func (db *DB) lExpireAt(key []byte, when int64) (int64, error) {
+	t := db.listTx
+	t.Lock()
+	defer t.Unlock()
+
+	if llen, err := db.LLen(key); err != nil || llen == 0 {
+		return 0, err
+	} else {
+		db.expireAt(t, lExpType, key, when)
+		if err := t.Commit(); err != nil {
+			return 0, err
+		}
+	}
+	return 1, nil
 }
 
 func (db *DB) LIndex(key []byte, index int32) ([]byte, error) {
@@ -347,41 +384,18 @@ func (db *DB) LClear(key []byte) (int64, error) {
 		return 0, err
 	}
 
-	mk := db.lEncodeMetaKey(key)
-
 	t := db.listTx
 	t.Lock()
 	defer t.Unlock()
 
-	var headSeq int32
+	num := db.lDelete(t, key)
-	var tailSeq int32
+	db.rmExpire(t, lExpType, key)
-	var err error
 
-	headSeq, tailSeq, _, err = db.lGetMeta(mk)
+	err := t.Commit()
-
-	if err != nil {
-		return 0, err
-	}
-
-	var num int64 = 0
-	startKey := db.lEncodeListKey(key, headSeq)
-	stopKey := db.lEncodeListKey(key, tailSeq)
-
-	it := db.db.Iterator(startKey, stopKey, leveldb.RangeClose, 0, -1)
-	for ; it.Valid(); it.Next() {
-		t.Delete(it.Key())
-		num++
-	}
-
-	it.Close()
-
-	t.Delete(mk)
-
-	err = t.Commit()
 	return num, err
 }
 
-func (db *DB) LFlush() (drop int64, err error) {
+func (db *DB) lFlush() (drop int64, err error) {
 	t := db.listTx
 	t.Lock()
 	defer t.Unlock()
@@ -398,8 +412,40 @@ func (db *DB) LFlush() (drop int64, err error) {
 	for ; it.Valid(); it.Next() {
 		t.Delete(it.Key())
 		drop++
+		if drop&1023 == 0 {
+			if err = t.Commit(); err != nil {
+				return
+			}
+		}
 	}
+	it.Close()
+
+	db.expFlush(t, lExpType)
 
 	err = t.Commit()
 	return
 }
+
+func (db *DB) LExpire(key []byte, duration int64) (int64, error) {
+	if duration <= 0 {
+		return 0, errExpireValue
+	}
+
+	return db.lExpireAt(key, time.Now().Unix()+duration)
+}
+
+func (db *DB) LExpireAt(key []byte, when int64) (int64, error) {
+	if when <= time.Now().Unix() {
+		return 0, errExpireValue
+	}
+
+	return db.lExpireAt(key, when)
+}
+
+func (db *DB) LTTL(key []byte) (int64, error) {
+	if err := checkKeySize(key); err != nil {
+		return -1, err
+	}
+
+	return db.ttl(lExpType, key)
+}

ledis/t_list_test.go

@@ -31,9 +31,37 @@ func TestDBList(t *testing.T) {
 
 	key := []byte("testdb_list_a")
 
-	if n, err := db.RPush(key, []byte("1"), []byte("2")); err != nil {
+	if n, err := db.RPush(key, []byte("1"), []byte("2"), []byte("3")); err != nil {
 		t.Fatal(err)
-	} else if n != 2 {
+	} else if n != 3 {
 		t.Fatal(n)
 	}
+
+	if k, err := db.RPop(key); err != nil {
+		t.Fatal(err)
+	} else if string(k) != "3" {
+		t.Fatal(string(k))
+	}
+
+	if k, err := db.LPop(key); err != nil {
+		t.Fatal(err)
+	} else if string(k) != "1" {
+		t.Fatal(string(k))
+	}
+
+	if llen, err := db.LLen(key); err != nil {
+		t.Fatal(err)
+	} else if llen != 1 {
+		t.Fatal(llen)
+	}
+
+	if num, err := db.LClear(key); err != nil {
+		t.Fatal(err)
+	} else if num != 1 {
+		t.Fatal(num)
+	}
+
+	if llen, _ := db.LLen(key); llen != 0 {
+		t.Fatal(llen)
+	}
 }

ledis/t_ttl.go

@@ -0,0 +1,212 @@
+package ledis
+
+import (
+	"encoding/binary"
+	"errors"
+	"github.com/siddontang/go-leveldb/leveldb"
+	"time"
+)
+
+var mapExpMetaType = map[byte]byte{
+	kvExpType: kvExpMetaType,
+	lExpType:  lExpMetaType,
+	hExpType:  hExpMetaType,
+	zExpType:  zExpMetaType}
+
+type retireCallback func(*tx, []byte) int64
+
+type elimination struct {
+	db         *DB
+	exp2Tx     map[byte]*tx
+	exp2Retire map[byte]retireCallback
+}
+
+var errExpType = errors.New("invalid expire type")
+
+func (db *DB) expEncodeTimeKey(expType byte, key []byte, when int64) []byte {
+	// format : db[8] / expType[8] / when[64] / key[...]
+	buf := make([]byte, len(key)+10)
+
+	buf[0] = db.index
+	buf[1] = expType
+	pos := 2
+
+	binary.BigEndian.PutUint64(buf[pos:], uint64(when))
+	pos += 8
+
+	copy(buf[pos:], key)
+
+	return buf
+}
+
+func (db *DB) expEncodeMetaKey(expType byte, key []byte) []byte {
+	// format : db[8] / expType[8] / key[...]
+	buf := make([]byte, len(key)+2)
+
+	buf[0] = db.index
+	buf[1] = expType
+	pos := 2
+
+	copy(buf[pos:], key)
+
+	return buf
+}
+
+// usage : separate out the original key
+func (db *DB) expDecodeMetaKey(mk []byte) []byte {
+	if len(mk) <= 2 {
+		//	check db ? check type ?
+		return nil
+	}
+
+	return mk[2:]
+}
+
+func (db *DB) expire(t *tx, expType byte, key []byte, duration int64) {
+	db.expireAt(t, expType, key, time.Now().Unix()+duration)
+}
+
+func (db *DB) expireAt(t *tx, expType byte, key []byte, when int64) {
+	mk := db.expEncodeMetaKey(expType+1, key)
+	tk := db.expEncodeTimeKey(expType, key, when)
+
+	t.Put(tk, mk)
+	t.Put(mk, PutInt64(when))
+}
+
+func (db *DB) ttl(expType byte, key []byte) (t int64, err error) {
+	mk := db.expEncodeMetaKey(expType+1, key)
+
+	if t, err = Int64(db.db.Get(mk)); err != nil || t == 0 {
+		t = -1
+	} else {
+		t -= time.Now().Unix()
+		if t <= 0 {
+			t = -1
+		}
+		// if t == -1 : to remove ????
+	}
+
+	return t, err
+}
+
+func (db *DB) rmExpire(t *tx, expType byte, key []byte) {
+	mk := db.expEncodeMetaKey(expType+1, key)
+	if v, err := db.db.Get(mk); err != nil || v == nil {
+		return
+	} else if when, err2 := Int64(v, nil); err2 != nil {
+		return
+	} else {
+		tk := db.expEncodeTimeKey(expType, key, when)
+		t.Delete(mk)
+		t.Delete(tk)
+	}
+}
+
+func (db *DB) expFlush(t *tx, expType byte) (err error) {
+	expMetaType, ok := mapExpMetaType[expType]
+	if !ok {
+		return errExpType
+	}
+
+	drop := 0
+
+	minKey := make([]byte, 2)
+	minKey[0] = db.index
+	minKey[1] = expType
+
+	maxKey := make([]byte, 2)
+	maxKey[0] = db.index
+	maxKey[1] = expMetaType + 1
+
+	it := db.db.Iterator(minKey, maxKey, leveldb.RangeROpen, 0, -1)
+	for ; it.Valid(); it.Next() {
+		t.Delete(it.Key())
+		drop++
+		if drop&1023 == 0 {
+			if err = t.Commit(); err != nil {
+				return
+			}
+		}
+	}
+	it.Close()
+
+	err = t.Commit()
+	return
+}
+
+//////////////////////////////////////////////////////////
+//
+//////////////////////////////////////////////////////////
+
+func newEliminator(db *DB) *elimination {
+	eli := new(elimination)
+	eli.db = db
+	eli.exp2Tx = make(map[byte]*tx)
+	eli.exp2Retire = make(map[byte]retireCallback)
+	return eli
+}
+
+func (eli *elimination) regRetireContext(expType byte, t *tx, onRetire retireCallback) {
+	eli.exp2Tx[expType] = t
+	eli.exp2Retire[expType] = onRetire
+}
+
+//	call by outside ... (from *db to another *db)
+func (eli *elimination) active() {
+	now := time.Now().Unix()
+	db := eli.db
+	dbGet := db.db.Get
+	expKeys := make([][]byte, 0, 1024)
+	expTypes := [...]byte{kvExpType, lExpType, hExpType, zExpType}
+
+	for _, et := range expTypes {
+		//	search those keys' which expire till the moment
+		minKey := db.expEncodeTimeKey(et, nil, 0)
+		maxKey := db.expEncodeTimeKey(et, nil, now+1)
+		expKeys = expKeys[0:0]
+
+		t, _ := eli.exp2Tx[et]
+		onRetire, _ := eli.exp2Retire[et]
+		if t == nil || onRetire == nil {
+			// todo : log error
+			continue
+		}
+
+		it := db.db.Iterator(minKey, maxKey, leveldb.RangeROpen, 0, -1)
+		for it.Valid() {
+			for i := 1; i < 512 && it.Valid(); i++ {
+				expKeys = append(expKeys, it.Key(), it.Value())
+				it.Next()
+			}
+
+			var cnt int = len(expKeys)
+			if cnt == 0 {
+				continue
+			}
+
+			t.Lock()
+			var mk, ek, k []byte
+			for i := 0; i < cnt; i += 2 {
+				ek, mk = expKeys[i], expKeys[i+1]
+				if exp, err := Int64(dbGet(mk)); err == nil {
+					// check expire again
+					if exp > now {
+						continue
+					}
+
+					// delete keys
+					k = db.expDecodeMetaKey(mk)
+					onRetire(t, k)
+					t.Delete(ek)
+					t.Delete(mk)
+				}
+			}
+			t.Commit()
+			t.Unlock()
+		} // end : it
+		it.Close()
+	} // end : expType
+
+	return
+}

ledis/t_ttl_test.go

@@ -0,0 +1,362 @@
+package ledis
+
+import (
+	"fmt"
+	"sync"
+	"testing"
+	"time"
+)
+
+var m sync.Mutex
+
+type adaptor struct {
+	set    func([]byte, []byte) (int64, error)
+	del    func([]byte) (int64, error)
+	exists func([]byte) (int64, error)
+
+	expire   func([]byte, int64) (int64, error)
+	expireAt func([]byte, int64) (int64, error)
+	ttl      func([]byte) (int64, error)
+
+	showIdent func() string
+}
+
+func kvAdaptor(db *DB) *adaptor {
+	adp := new(adaptor)
+	adp.showIdent = func() string {
+		return "kv-adptor"
+	}
+
+	adp.set = db.SetNX
+	adp.exists = db.Exists
+	adp.del = func(k []byte) (int64, error) {
+		return db.Del(k)
+	}
+
+	adp.expire = db.Expire
+	adp.expireAt = db.ExpireAt
+	adp.ttl = db.TTL
+
+	return adp
+}
+
+func listAdaptor(db *DB) *adaptor {
+	adp := new(adaptor)
+	adp.showIdent = func() string {
+		return "list-adptor"
+	}
+
+	adp.set = func(k []byte, v []byte) (int64, error) {
+		eles := make([][]byte, 0)
+		for i := 0; i < 3; i++ {
+			e := []byte(String(v) + fmt.Sprintf("_%d", i))
+			eles = append(eles, e)
+		}
+
+		if n, err := db.LPush(k, eles...); err != nil {
+			return 0, err
+		} else {
+			return n, nil
+		}
+	}
+
+	adp.exists = func(k []byte) (int64, error) {
+		if llen, err := db.LLen(k); err != nil || llen <= 0 {
+			return 0, err
+		} else {
+			return 1, nil
+		}
+	}
+
+	adp.del = db.LClear
+	adp.expire = db.LExpire
+	adp.expireAt = db.LExpireAt
+	adp.ttl = db.LTTL
+
+	return adp
+}
+
+func hashAdaptor(db *DB) *adaptor {
+	adp := new(adaptor)
+	adp.showIdent = func() string {
+		return "hash-adptor"
+	}
+
+	adp.set = func(k []byte, v []byte) (int64, error) {
+		datas := make([]FVPair, 0)
+		for i := 0; i < 3; i++ {
+			suffix := fmt.Sprintf("_%d", i)
+			pair := FVPair{
+				Field: []byte(String(k) + suffix),
+				Value: []byte(String(v) + suffix)}
+
+			datas = append(datas, pair)
+		}
+
+		if err := db.HMset(k, datas...); err != nil {
+			return 0, err
+		} else {
+			return int64(len(datas)), nil
+		}
+	}
+
+	adp.exists = func(k []byte) (int64, error) {
+		if hlen, err := db.HLen(k); err != nil || hlen <= 0 {
+			return 0, err
+		} else {
+			return 1, nil
+		}
+	}
+
+	adp.del = db.HClear
+	adp.expire = db.HExpire
+	adp.expireAt = db.HExpireAt
+	adp.ttl = db.HTTL
+
+	return adp
+}
+
+func zsetAdaptor(db *DB) *adaptor {
+	adp := new(adaptor)
+	adp.showIdent = func() string {
+		return "zset-adptor"
+	}
+
+	adp.set = func(k []byte, v []byte) (int64, error) {
+		datas := make([]ScorePair, 0)
+		for i := 0; i < 3; i++ {
+			memb := []byte(String(k) + fmt.Sprintf("_%d", i))
+			pair := ScorePair{
+				Score:  int64(i),
+				Member: memb}
+
+			datas = append(datas, pair)
+		}
+
+		if n, err := db.ZAdd(k, datas...); err != nil {
+			return 0, err
+		} else {
+			return n, nil
+		}
+	}
+
+	adp.exists = func(k []byte) (int64, error) {
+		if cnt, err := db.ZCard(k); err != nil || cnt <= 0 {
+			return 0, err
+		} else {
+			return 1, nil
+		}
+	}
+
+	adp.del = db.ZClear
+	adp.expire = db.ZExpire
+	adp.expireAt = db.ZExpireAt
+	adp.ttl = db.ZTTL
+
+	return adp
+}
+
+func allAdaptors(db *DB) []*adaptor {
+	adps := make([]*adaptor, 4)
+	adps[0] = kvAdaptor(db)
+	adps[1] = listAdaptor(db)
+	adps[2] = hashAdaptor(db)
+	adps[3] = zsetAdaptor(db)
+	return adps
+}
+
+///////////////////////////////////////////////////////
+
+func TestExpire(t *testing.T) {
+	db := getTestDB()
+	m.Lock()
+	defer m.Unlock()
+
+	k := []byte("ttl_a")
+	ek := []byte("ttl_b")
+
+	dbEntrys := allAdaptors(db)
+	for _, entry := range dbEntrys {
+		ident := entry.showIdent()
+
+		entry.set(k, []byte("1"))
+
+		if ok, _ := entry.expire(k, 10); ok != 1 {
+			t.Fatal(ident, ok)
+		}
+
+		//	err - expire on an inexisting key
+		if ok, _ := entry.expire(ek, 10); ok != 0 {
+			t.Fatal(ident, ok)
+		}
+
+		//	err - duration is zero
+		if ok, err := entry.expire(k, 0); err == nil || ok != 0 {
+			t.Fatal(ident, fmt.Sprintf("res = %d, err = %s", ok, err))
+		}
+
+		//	err - duration is negative
+		if ok, err := entry.expire(k, -10); err == nil || ok != 0 {
+			t.Fatal(ident, fmt.Sprintf("res = %d, err = %s", ok, err))
+		}
+	}
+}
+
+func TestExpireAt(t *testing.T) {
+	db := getTestDB()
+	m.Lock()
+	defer m.Unlock()
+
+	k := []byte("ttl_a")
+	ek := []byte("ttl_b")
+
+	dbEntrys := allAdaptors(db)
+	for _, entry := range dbEntrys {
+		ident := entry.showIdent()
+		now := time.Now().Unix()
+
+		entry.set(k, []byte("1"))
+
+		if ok, _ := entry.expireAt(k, now+5); ok != 1 {
+			t.Fatal(ident, ok)
+		}
+
+		//	err - expire on an inexisting key
+		if ok, _ := entry.expireAt(ek, now+5); ok != 0 {
+			t.Fatal(ident, ok)
+		}
+
+		//	err - expire with the current time
+		if ok, err := entry.expireAt(k, now); err == nil || ok != 0 {
+			t.Fatal(ident, fmt.Sprintf("res = %d, err = %s", ok, err))
+		}
+
+		//	err - expire with the time before
+		if ok, err := entry.expireAt(k, now-5); err == nil || ok != 0 {
+			t.Fatal(ident, fmt.Sprintf("res = %d, err = %s", ok, err))
+		}
+	}
+}
+
+func TestTTL(t *testing.T) {
+	db := getTestDB()
+	m.Lock()
+	defer m.Unlock()
+
+	k := []byte("ttl_a")
+	ek := []byte("ttl_b")
+
+	dbEntrys := allAdaptors(db)
+	for _, entry := range dbEntrys {
+		ident := entry.showIdent()
+
+		entry.set(k, []byte("1"))
+		entry.expire(k, 2)
+
+		if tRemain, _ := entry.ttl(k); tRemain != 2 {
+			t.Fatal(ident, tRemain)
+		}
+
+		//	err - check ttl on an inexisting key
+		if tRemain, _ := entry.ttl(ek); tRemain != -1 {
+			t.Fatal(ident, tRemain)
+		}
+
+		entry.del(k)
+		if tRemain, _ := entry.ttl(k); tRemain != -1 {
+			t.Fatal(ident, tRemain)
+		}
+	}
+}
+
+func TestExpCompose(t *testing.T) {
+	db := getTestDB()
+	m.Lock()
+	defer m.Unlock()
+
+	k0 := []byte("ttl_a")
+	k1 := []byte("ttl_b")
+	k2 := []byte("ttl_c")
+
+	dbEntrys := allAdaptors(db)
+
+	for _, entry := range dbEntrys {
+		ident := entry.showIdent()
+
+		entry.set(k0, k0)
+		entry.set(k1, k1)
+		entry.set(k2, k2)
+
+		entry.expire(k0, 5)
+		entry.expire(k1, 2)
+		entry.expire(k2, 60)
+
+		if tRemain, _ := entry.ttl(k0); tRemain != 5 {
+			t.Fatal(ident, tRemain)
+		}
+		if tRemain, _ := entry.ttl(k1); tRemain != 2 {
+			t.Fatal(ident, tRemain)
+		}
+		if tRemain, _ := entry.ttl(k2); tRemain != 60 {
+			t.Fatal(ident, tRemain)
+		}
+	}
+
+	// after 1 sec
+	time.Sleep(1 * time.Second)
+
+	for _, entry := range dbEntrys {
+		ident := entry.showIdent()
+
+		if tRemain, _ := entry.ttl(k0); tRemain != 4 {
+			t.Fatal(ident, tRemain)
+		}
+		if tRemain, _ := entry.ttl(k1); tRemain != 1 {
+			t.Fatal(ident, tRemain)
+		}
+	}
+
+	// after 2 sec
+	time.Sleep(2 * time.Second)
+
+	for _, entry := range dbEntrys {
+		ident := entry.showIdent()
+
+		if tRemain, _ := entry.ttl(k1); tRemain != -1 {
+			t.Fatal(ident, tRemain)
+		}
+		if exist, _ := entry.exists(k1); exist > 0 {
+			t.Fatal(ident, false)
+		}
+
+		if tRemain, _ := entry.ttl(k0); tRemain != 2 {
+			t.Fatal(ident, tRemain)
+		}
+		if exist, _ := entry.exists(k0); exist <= 0 {
+			t.Fatal(ident, false)
+		}
+
+		// refresh the expiration of key
+		if tRemain, _ := entry.ttl(k2); !(0 < tRemain && tRemain < 60) {
+			t.Fatal(ident, tRemain)
+		}
+
+		if ok, _ := entry.expire(k2, 100); ok != 1 {
+			t.Fatal(ident, false)
+		}
+
+		if tRemain, _ := entry.ttl(k2); tRemain != 100 {
+			t.Fatal(ident, tRemain)
+		}
+
+		//	expire an inexisting key
+		if ok, _ := entry.expire(k1, 10); ok == 1 {
+			t.Fatal(ident, false)
+		}
+		if tRemain, _ := entry.ttl(k1); tRemain != -1 {
+			t.Fatal(ident, tRemain)
+		}
+	}
+
+	return
+}

ledis/t_zset.go

@@ -5,6 +5,7 @@ import (
 	"encoding/binary"
 	"errors"
 	"github.com/siddontang/go-leveldb/leveldb"
+	"time"
 )
 
 const (
@@ -34,9 +35,9 @@ const (
 
 func checkZSetKMSize(key []byte, member []byte) error {
 	if len(key) > MaxKeySize || len(key) == 0 {
-		return ErrKeySize
+		return errKeySize
 	} else if len(member) > MaxZSetMemberSize || len(member) == 0 {
-		return ErrZSetMemberSize
+		return errZSetMemberSize
 	}
 	return nil
 }
@@ -191,13 +192,11 @@ func (db *DB) zDecodeScoreKey(ek []byte) (key []byte, member []byte, score int64
 	return
 }
 
-func (db *DB) zSetItem(key []byte, score int64, member []byte) (int64, error) {
+func (db *DB) zSetItem(t *tx, key []byte, score int64, member []byte) (int64, error) {
 	if score <= MinScore || score >= MaxScore {
 		return 0, errScoreOverflow
 	}
 
-	t := db.zsetTx
-
 	var exists int64 = 0
 	ek := db.zEncodeSetKey(key, member)
 
@@ -222,9 +221,7 @@ func (db *DB) zSetItem(key []byte, score int64, member []byte) (int64, error) {
 	return exists, nil
 }
 
-func (db *DB) zDelItem(key []byte, member []byte, skipDelScore bool) (int64, error) {
+func (db *DB) zDelItem(t *tx, key []byte, member []byte, skipDelScore bool) (int64, error) {
-	t := db.zsetTx
-
 	ek := db.zEncodeSetKey(key, member)
 	if v, err := db.db.Get(ek); err != nil {
 		return 0, err
@@ -245,6 +242,29 @@ func (db *DB) zDelItem(key []byte, member []byte, skipDelScore bool) (int64, err
 	}
 
 	t.Delete(ek)
+
+	return 1, nil
+}
+
+func (db *DB) zDelete(t *tx, key []byte) int64 {
+	delMembCnt, _ := db.zRemRange(t, key, MinScore, MaxScore, 0, -1)
+	//	todo : log err
+	return delMembCnt
+}
+
+func (db *DB) zExpireAt(key []byte, when int64) (int64, error) {
+	t := db.zsetTx
+	t.Lock()
+	defer t.Unlock()
+
+	if zcnt, err := db.ZCard(key); err != nil || zcnt == 0 {
+		return 0, err
+	} else {
+		db.expireAt(t, zExpType, key, when)
+		if err := t.Commit(); err != nil {
+			return 0, err
+		}
+	}
 	return 1, nil
 }
 
@@ -266,7 +286,7 @@ func (db *DB) ZAdd(key []byte, args ...ScorePair) (int64, error) {
 			return 0, err
 		}
 
-		if n, err := db.zSetItem(key, score, member); err != nil {
+		if n, err := db.zSetItem(t, key, score, member); err != nil {
 			return 0, err
 		} else if n == 0 {
 			//add new
@@ -274,7 +294,7 @@ func (db *DB) ZAdd(key []byte, args ...ScorePair) (int64, error) {
 		}
 	}
 
-	if _, err := db.zIncrSize(key, num); err != nil {
+	if _, err := db.zIncrSize(t, key, num); err != nil {
 		return 0, err
 	}
 
@@ -283,8 +303,7 @@ func (db *DB) ZAdd(key []byte, args ...ScorePair) (int64, error) {
 	return num, err
 }
 
-func (db *DB) zIncrSize(key []byte, delta int64) (int64, error) {
+func (db *DB) zIncrSize(t *tx, key []byte, delta int64) (int64, error) {
-	t := db.zsetTx
 	sk := db.zEncodeSizeKey(key)
 
 	size, err := Int64(db.db.Get(sk))
@@ -295,6 +314,7 @@ func (db *DB) zIncrSize(key []byte, delta int64) (int64, error) {
 		if size <= 0 {
 			size = 0
 			t.Delete(sk)
+			db.rmExpire(t, zExpType, key)
 		} else {
 			t.Put(sk, PutInt64(size))
 		}
@@ -348,14 +368,14 @@ func (db *DB) ZRem(key []byte, members ...[]byte) (int64, error) {
 			return 0, err
 		}
 
-		if n, err := db.zDelItem(key, members[i], false); err != nil {
+		if n, err := db.zDelItem(t, key, members[i], false); err != nil {
 			return 0, err
 		} else if n == 1 {
 			num++
 		}
 	}
 
-	if _, err := db.zIncrSize(key, -num); err != nil {
+	if _, err := db.zIncrSize(t, key, -num); err != nil {
 		return 0, err
 	}
 
@@ -374,34 +394,35 @@ func (db *DB) ZIncrBy(key []byte, delta int64, member []byte) (int64, error) {
 
 	ek := db.zEncodeSetKey(key, member)
 
-	var score int64 = delta
+	var oldScore int64 = 0
-
 	v, err := db.db.Get(ek)
 	if err != nil {
 		return InvalidScore, err
-	} else if v != nil {
+	} else if v == nil {
-		if s, err := Int64(v, err); err != nil {
+		db.zIncrSize(t, key, 1)
-			return InvalidScore, err
-		} else {
-			sk := db.zEncodeScoreKey(key, member, s)
-			t.Delete(sk)
-
-			score = s + delta
-			if score >= MaxScore || score <= MinScore {
-				return InvalidScore, errScoreOverflow
-			}
-		}
 	} else {
-		db.zIncrSize(key, 1)
+		if oldScore, err = Int64(v, err); err != nil {
+			return InvalidScore, err
+		}
 	}
 
-	t.Put(ek, PutInt64(score))
+	newScore := oldScore + delta
+	if newScore >= MaxScore || newScore <= MinScore {
+		return InvalidScore, errScoreOverflow
+	}
 
-	sk := db.zEncodeScoreKey(key, member, score)
+	sk := db.zEncodeScoreKey(key, member, newScore)
 	t.Put(sk, []byte{})
+	t.Put(ek, PutInt64(newScore))
+
+	if v != nil {
+		// so as to update score, we must delete the old one
+		oldSk := db.zEncodeScoreKey(key, member, oldScore)
+		t.Delete(oldSk)
+	}
 
 	err = t.Commit()
-	return score, err
+	return newScore, err
 }
 
 func (db *DB) ZCount(key []byte, min int64, max int64) (int64, error) {
@@ -482,41 +503,35 @@ func (db *DB) zIterator(key []byte, min int64, max int64, offset int, limit int,
 	}
 }
 
-func (db *DB) zRemRange(key []byte, min int64, max int64, offset int, limit int) (int64, error) {
+func (db *DB) zRemRange(t *tx, key []byte, min int64, max int64, offset int, limit int) (int64, error) {
 	if len(key) > MaxKeySize {
-		return 0, ErrKeySize
+		return 0, errKeySize
 	}
 
-	t := db.zsetTx
-	t.Lock()
-	defer t.Unlock()
-
 	it := db.zIterator(key, min, max, offset, limit, false)
 	var num int64 = 0
 	for ; it.Valid(); it.Next() {
-		k := it.Key()
+		sk := it.Key()
-		_, m, _, err := db.zDecodeScoreKey(k)
+		_, m, _, err := db.zDecodeScoreKey(sk)
 		if err != nil {
 			continue
 		}
 
-		if n, err := db.zDelItem(key, m, true); err != nil {
+		if n, err := db.zDelItem(t, key, m, true); err != nil {
 			return 0, err
 		} else if n == 1 {
 			num++
 		}
 
-		t.Delete(k)
+		t.Delete(sk)
 	}
+	it.Close()
 
-	if _, err := db.zIncrSize(key, -num); err != nil {
+	if _, err := db.zIncrSize(t, key, -num); err != nil {
 		return 0, err
 	}
 
-	//todo add binlog
+	return num, nil
-
-	err := t.Commit()
-	return num, err
 }
 
 func (db *DB) zReverse(s []interface{}, withScores bool) []interface{} {
@@ -536,7 +551,7 @@ func (db *DB) zReverse(s []interface{}, withScores bool) []interface{} {
 
 func (db *DB) zRange(key []byte, min int64, max int64, withScores bool, offset int, limit int, reverse bool) ([]interface{}, error) {
 	if len(key) > MaxKeySize {
-		return nil, ErrKeySize
+		return nil, errKeySize
 	}
 
 	if offset < 0 {
@@ -575,6 +590,7 @@ func (db *DB) zRange(key []byte, min int64, max int64, withScores bool, offset i
 			v = append(v, m)
 		}
 	}
+	it.Close()
 
 	if reverse && (offset == 0 && limit < 0) {
 		v = db.zReverse(v, withScores)
@@ -622,7 +638,16 @@ func (db *DB) zParseLimit(key []byte, start int, stop int) (offset int, limit in
 }
 
 func (db *DB) ZClear(key []byte) (int64, error) {
-	return db.zRemRange(key, MinScore, MaxScore, 0, -1)
+	t := db.zsetTx
+	t.Lock()
+	defer t.Unlock()
+
+	rmCnt, err := db.zRemRange(t, key, MinScore, MaxScore, 0, -1)
+	if err == nil {
+		err = t.Commit()
+	}
+
+	return rmCnt, err
 }
 
 func (db *DB) ZRange(key []byte, start int, stop int, withScores bool) ([]interface{}, error) {
@@ -645,12 +670,33 @@ func (db *DB) ZRemRangeByRank(key []byte, start int, stop int) (int64, error) {
 	if err != nil {
 		return 0, err
 	}
-	return db.zRemRange(key, MinScore, MaxScore, offset, limit)
+
+	var rmCnt int64
+
+	t := db.zsetTx
+	t.Lock()
+	defer t.Unlock()
+
+	rmCnt, err = db.zRemRange(t, key, MinScore, MaxScore, offset, limit)
+	if err == nil {
+		err = t.Commit()
+	}
+
+	return rmCnt, err
 }
 
 //min and max must be inclusive
 func (db *DB) ZRemRangeByScore(key []byte, min int64, max int64) (int64, error) {
-	return db.zRemRange(key, min, max, 0, -1)
+	t := db.zsetTx
+	t.Lock()
+	defer t.Unlock()
+
+	rmCnt, err := db.zRemRange(t, key, min, max, 0, -1)
+	if err == nil {
+		err = t.Commit()
+	}
+
+	return rmCnt, err
 }
 
 func (db *DB) ZRevRange(key []byte, start int, stop int, withScores bool) ([]interface{}, error) {
@@ -686,7 +732,7 @@ func (db *DB) ZRangeByScoreGeneric(key []byte, min int64, max int64,
 	return db.zRange(key, min, max, withScores, offset, count, reverse)
 }
 
-func (db *DB) ZFlush() (drop int64, err error) {
+func (db *DB) zFlush() (drop int64, err error) {
 	t := db.zsetTx
 	t.Lock()
 	defer t.Unlock()
@@ -703,10 +749,17 @@ func (db *DB) ZFlush() (drop int64, err error) {
 	for ; it.Valid(); it.Next() {
 		t.Delete(it.Key())
 		drop++
+		if drop&1023 == 0 {
+			if err = t.Commit(); err != nil {
+				return
+			}
+		}
 	}
+	it.Close()
+
+	db.expFlush(t, zExpType)
 
 	err = t.Commit()
-	// to do : binlog
 	return
 }
 
@@ -744,6 +797,31 @@ func (db *DB) ZScan(key []byte, member []byte, count int, inclusive bool) ([]Sco
 			v = append(v, ScorePair{Member: m, Score: score})
 		}
 	}
+	it.Close()
 
 	return v, nil
 }
+
+func (db *DB) ZExpire(key []byte, duration int64) (int64, error) {
+	if duration <= 0 {
+		return 0, errExpireValue
+	}
+
+	return db.zExpireAt(key, time.Now().Unix()+duration)
+}
+
+func (db *DB) ZExpireAt(key []byte, when int64) (int64, error) {
+	if when <= time.Now().Unix() {
+		return 0, errExpireValue
+	}
+
+	return db.zExpireAt(key, when)
+}
+
+func (db *DB) ZTTL(key []byte) (int64, error) {
+	if err := checkKeySize(key); err != nil {
+		return -1, err
+	}
+
+	return db.ttl(zExpType, key)
+}

ledis/t_zset_test.go

@@ -220,7 +220,7 @@ func TestZSetOrder(t *testing.T) {
 func TestDBZScan(t *testing.T) {
 	db := getTestDB()
 
-	db.ZFlush()
+	db.zFlush()
 
 	key := []byte("key")
 	db.ZAdd(key, pair("a", 0), pair("b", 1), pair("c", 2))

ledis/tx.go

@@ -8,7 +8,22 @@ import (
 type tx struct {
 	m sync.Mutex
 
+	l  *Ledis
 	wb *leveldb.WriteBatch
+
+	binlog *BinLog
+	batch  [][]byte
+}
+
+func newTx(l *Ledis) *tx {
+	t := new(tx)
+
+	t.l = l
+	t.wb = l.ldb.NewWriteBatch()
+
+	t.batch = make([][]byte, 0, 4)
+	t.binlog = l.binlog
+	return t
 }
 
 func (t *tx) Close() {
@@ -17,10 +32,20 @@ func (t *tx) Close() {
 
 func (t *tx) Put(key []byte, value []byte) {
 	t.wb.Put(key, value)
+
+	if t.binlog != nil {
+		buf := encodeBinLogPut(key, value)
+		t.batch = append(t.batch, buf)
+	}
 }
 
 func (t *tx) Delete(key []byte) {
 	t.wb.Delete(key)
+
+	if t.binlog != nil {
+		buf := encodeBinLogDelete(key)
+		t.batch = append(t.batch, buf)
+	}
 }
 
 func (t *tx) Lock() {
@@ -28,12 +53,29 @@ func (t *tx) Lock() {
 }
 
 func (t *tx) Unlock() {
+	t.batch = t.batch[0:0]
 	t.wb.Rollback()
 	t.m.Unlock()
 }
 
 func (t *tx) Commit() error {
-	err := t.wb.Commit()
+	var err error
+	if t.binlog != nil {
+		t.l.Lock()
+		err = t.wb.Commit()
+		if err != nil {
+			t.l.Unlock()
+			return err
+		}
+
+		err = t.binlog.Log(t.batch...)
+
+		t.l.Unlock()
+	} else {
+		t.l.Lock()
+		err = t.wb.Commit()
+		t.l.Unlock()
+	}
 	return err
 }
 

server/accesslog.go

@@ -0,0 +1,51 @@
+package server
+
+import (
+	"fmt"
+	"github.com/siddontang/go-log/log"
+	"strings"
+)
+
+const (
+	accessTimeFormat = "2006/01/02 15:04:05"
+)
+
+type accessLog struct {
+	l *log.Logger
+}
+
+func newAcessLog(baseName string) (*accessLog, error) {
+	l := new(accessLog)
+
+	h, err := log.NewTimeRotatingFileHandler(baseName, log.WhenDay, 1)
+	if err != nil {
+		return nil, err
+	}
+
+	l.l = log.New(h, log.Ltime)
+
+	return l, nil
+}
+
+func (l *accessLog) Close() {
+	l.l.Close()
+}
+
+func (l *accessLog) Log(remoteAddr string, usedTime int64, cmd string, args [][]byte, err error) {
+	argsFormat := make([]string, len(args))
+	argsI := make([]interface{}, len(args))
+	for i := range args {
+		argsFormat[i] = " %.24q"
+		argsI[i] = args[i]
+	}
+
+	argsStr := fmt.Sprintf(strings.Join(argsFormat, ""), argsI...)
+
+	format := `%s [%s%s] %d [%s]`
+
+	if err == nil {
+		l.l.Info(format, remoteAddr, cmd, argsStr, usedTime, "OK")
+	} else {
+		l.l.Info(format, remoteAddr, cmd, argsStr, usedTime, err.Error())
+	}
+}

server/app.go

@@ -1,8 +1,10 @@
 package server
 
 import (
+	"fmt"
 	"github.com/siddontang/ledisdb/ledis"
 	"net"
+	"path"
 	"strings"
 )
 
@@ -14,11 +16,28 @@ type App struct {
 	ldb *ledis.Ledis
 
 	closed bool
+
+	quit chan struct{}
+
+	access *accessLog
+
+	//for slave replication
+	m *master
 }
 
 func NewApp(cfg *Config) (*App, error) {
+	if len(cfg.DataDir) == 0 {
+		return nil, fmt.Errorf("must set data_dir first")
+	}
+
+	if len(cfg.DB.DataDir) == 0 {
+		cfg.DB.DataDir = cfg.DataDir
+	}
+
 	app := new(App)
 
+	app.quit = make(chan struct{})
+
 	app.closed = false
 
 	app.cfg = cfg
@@ -35,11 +54,24 @@ func NewApp(cfg *Config) (*App, error) {
 		return nil, err
 	}
 
-	app.ldb, err = ledis.OpenWithConfig(&cfg.DB)
+	if len(cfg.AccessLog) > 0 {
-	if err != nil {
+		if path.Dir(cfg.AccessLog) == "." {
+			app.access, err = newAcessLog(path.Join(cfg.DataDir, cfg.AccessLog))
+		} else {
+			app.access, err = newAcessLog(cfg.AccessLog)
+		}
+
+		if err != nil {
+			return nil, err
+		}
+	}
+
+	if app.ldb, err = ledis.OpenWithConfig(&cfg.DB); err != nil {
 		return nil, err
 	}
 
+	app.m = newMaster(app)
+
 	return app, nil
 }
 
@@ -48,20 +80,36 @@ func (app *App) Close() {
 		return
 	}
 
+	app.closed = true
+
+	close(app.quit)
+
 	app.listener.Close()
 
-	app.ldb.Close()
+	app.m.Close()
 
-	app.closed = true
+	if app.access != nil {
+		app.access.Close()
+	}
+
+	app.ldb.Close()
 }
 
 func (app *App) Run() {
+	if len(app.cfg.SlaveOf) > 0 {
+		app.slaveof(app.cfg.SlaveOf)
+	}
+
 	for !app.closed {
 		conn, err := app.listener.Accept()
 		if err != nil {
 			continue
 		}
 
-		newClient(conn, app.ldb)
+		newClient(conn, app)
 	}
 }
+
+func (app *App) Ledis() *ledis.Ledis {
+	return app.ldb
+}

server/app_test.go

@@ -38,10 +38,10 @@ func startTestApp() {
 
 		var d = []byte(`
             {
+                "data_dir" : "/tmp/testdb",
                 "addr" : "127.0.0.1:16380",
                 "db" : {
                     "data_db" : {
-                        "path" : "/tmp/testdb",
                         "compression":true,
                         "block_size" : 32768,
                         "write_buffer_size" : 2097152,

server/client.go

@@ -2,6 +2,7 @@ package server
 
 import (
 	"bufio"
+	"bytes"
 	"errors"
 	"github.com/siddontang/go-log/log"
 	"github.com/siddontang/ledisdb/ledis"
@@ -10,11 +11,13 @@ import (
 	"runtime"
 	"strconv"
 	"strings"
+	"time"
 )
 
 var errReadRequest = errors.New("invalid request protocol")
 
 type client struct {
+	app *App
 	ldb *ledis.Ledis
 
 	db *ledis.DB
@@ -27,13 +30,17 @@ type client struct {
 	args [][]byte
 
 	reqC chan error
+
+	syncBuf bytes.Buffer
 }
 
-func newClient(c net.Conn, ldb *ledis.Ledis) {
+func newClient(c net.Conn, app *App) {
 	co := new(client)
-	co.ldb = ldb
+
+	co.app = app
+	co.ldb = app.ldb
 	//use default db
-	co.db, _ = ldb.Select(0)
+	co.db, _ = app.ldb.Select(0)
 	co.c = c
 
 	co.rb = bufio.NewReaderSize(c, 256)
@@ -68,22 +75,7 @@ func (c *client) run() {
 }
 
 func (c *client) readLine() ([]byte, error) {
-	var line []byte
+	return readLine(c.rb)
-	for {
-		l, more, err := c.rb.ReadLine()
-		if err != nil {
-			return nil, err
-		}
-
-		if line == nil && !more {
-			return l, nil
-		}
-		line = append(line, l...)
-		if !more {
-			break
-		}
-	}
-	return line, nil
 }
 
 //A client sends to the Redis server a RESP Array consisting of just Bulk Strings.
@@ -118,15 +110,19 @@ func (c *client) readRequest() ([][]byte, error) {
 			} else if n == -1 {
 				req = append(req, nil)
 			} else {
-				buf := make([]byte, n+2)
+				buf := make([]byte, n)
 				if _, err = io.ReadFull(c.rb, buf); err != nil {
 					return nil, err
-				} else if buf[len(buf)-2] != '\r' || buf[len(buf)-1] != '\n' {
-					return nil, errReadRequest
-
-				} else {
-					req = append(req, buf[0:len(buf)-2])
 				}
+
+				if l, err = c.readLine(); err != nil {
+					return nil, err
+				} else if len(l) != 0 {
+					return nil, errors.New("bad bulk string format")
+				}
+
+				req = append(req, buf)
+
 			}
 
 		} else {
@@ -140,6 +136,8 @@ func (c *client) readRequest() ([][]byte, error) {
 func (c *client) handleRequest(req [][]byte) {
 	var err error
 
+	start := time.Now()
+
 	if len(req) == 0 {
 		err = ErrEmptyCommand
 	} else {
@@ -157,6 +155,12 @@ func (c *client) handleRequest(req [][]byte) {
 		}
 	}
 
+	duration := time.Since(start)
+
+	if c.app.access != nil {
+		c.app.access.Log(c.c.RemoteAddr().String(), duration.Nanoseconds()/1000000, c.cmd, c.args, err)
+	}
+
 	if err != nil {
 		c.writeError(err)
 	}
@@ -223,3 +227,12 @@ func (c *client) writeArray(ay []interface{}) {
 		}
 	}
 }
+
+func (c *client) writeBulkFrom(n int64, rb io.Reader) {
+	c.wb.WriteByte('$')
+	c.wb.Write(ledis.Slice(strconv.FormatInt(n, 10)))
+	c.wb.Write(Delims)
+
+	io.Copy(c.wb, rb)
+	c.wb.Write(Delims)
+}

server/cmd_kv.go

@@ -20,7 +20,7 @@ func getCommand(c *client) error {
 
 func setCommand(c *client) error {
 	args := c.args
-	if len(args) < 2 {
+	if len(args) != 2 {
 		return ErrCmdParams
 	}
 

server/cmd_replication.go

@@ -0,0 +1,116 @@
+package server
+
+import (
+	"encoding/binary"
+	"fmt"
+	"github.com/siddontang/ledisdb/ledis"
+	"io/ioutil"
+	"os"
+	"strconv"
+	"strings"
+)
+
+func slaveofCommand(c *client) error {
+	args := c.args
+
+	if len(args) != 2 {
+		return ErrCmdParams
+	}
+
+	masterAddr := ""
+
+	if strings.ToLower(ledis.String(args[0])) == "no" &&
+		strings.ToLower(ledis.String(args[1])) == "one" {
+		//stop replication, use master = ""
+	} else {
+		if _, err := strconv.ParseInt(ledis.String(args[1]), 10, 16); err != nil {
+			return err
+		}
+
+		masterAddr = fmt.Sprintf("%s:%s", args[0], args[1])
+	}
+
+	if err := c.app.slaveof(masterAddr); err != nil {
+		return err
+	}
+
+	c.writeStatus(OK)
+
+	return nil
+}
+
+func fullsyncCommand(c *client) error {
+	//todo, multi fullsync may use same dump file
+	dumpFile, err := ioutil.TempFile(c.app.cfg.DataDir, "dump_")
+	if err != nil {
+		return err
+	}
+
+	if err = c.app.ldb.Dump(dumpFile); err != nil {
+		return err
+	}
+
+	st, _ := dumpFile.Stat()
+	n := st.Size()
+
+	dumpFile.Seek(0, os.SEEK_SET)
+
+	c.writeBulkFrom(n, dumpFile)
+
+	name := dumpFile.Name()
+	dumpFile.Close()
+
+	os.Remove(name)
+
+	return nil
+}
+
+var reserveInfoSpace = make([]byte, 16)
+
+func syncCommand(c *client) error {
+	args := c.args
+	if len(args) != 2 {
+		return ErrCmdParams
+	}
+
+	var logIndex int64
+	var logPos int64
+	var err error
+	logIndex, err = ledis.StrInt64(args[0], nil)
+	if err != nil {
+		return ErrCmdParams
+	}
+
+	logPos, err = ledis.StrInt64(args[1], nil)
+	if err != nil {
+		return ErrCmdParams
+	}
+
+	c.syncBuf.Reset()
+
+	//reserve space to write master info
+	if _, err := c.syncBuf.Write(reserveInfoSpace); err != nil {
+		return err
+	}
+
+	m := &ledis.MasterInfo{logIndex, logPos}
+
+	if _, err := c.app.ldb.ReadEventsTo(m, &c.syncBuf); err != nil {
+		return err
+	} else {
+		buf := c.syncBuf.Bytes()
+
+		binary.BigEndian.PutUint64(buf[0:], uint64(m.LogFileIndex))
+		binary.BigEndian.PutUint64(buf[8:], uint64(m.LogPos))
+
+		c.writeBulk(buf)
+	}
+
+	return nil
+}
+
+func init() {
+	register("slaveof", slaveofCommand)
+	register("fullsync", fullsyncCommand)
+	register("sync", syncCommand)
+}

server/cmd_replication_test.go

@@ -0,0 +1,107 @@
+package server
+
+import (
+	"bytes"
+	"fmt"
+	"github.com/siddontang/go-leveldb/leveldb"
+	"os"
+	"testing"
+	"time"
+)
+
+func checkDataEqual(master *App, slave *App) error {
+	it := master.ldb.DataDB().Iterator(nil, nil, leveldb.RangeClose, 0, -1)
+	for ; it.Valid(); it.Next() {
+		key := it.Key()
+		value := it.Value()
+
+		if v, err := slave.ldb.DataDB().Get(key); err != nil {
+			return err
+		} else if !bytes.Equal(v, value) {
+			return fmt.Errorf("replication error %d != %d", len(v), len(value))
+		}
+	}
+
+	return nil
+}
+
+func TestReplication(t *testing.T) {
+	data_dir := "/tmp/test_replication"
+	os.RemoveAll(data_dir)
+
+	masterCfg := new(Config)
+	masterCfg.DataDir = fmt.Sprintf("%s/master", data_dir)
+	masterCfg.Addr = "127.0.0.1:11182"
+	masterCfg.DB.UseBinLog = true
+
+	var master *App
+	var slave *App
+	var err error
+	master, err = NewApp(masterCfg)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	slaveCfg := new(Config)
+	slaveCfg.DataDir = fmt.Sprintf("%s/slave", data_dir)
+	slaveCfg.Addr = "127.0.0.1:11183"
+	slaveCfg.SlaveOf = masterCfg.Addr
+
+	slave, err = NewApp(slaveCfg)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	go master.Run()
+
+	db, _ := master.ldb.Select(0)
+
+	value := make([]byte, 10)
+
+	db.Set([]byte("a"), value)
+	db.Set([]byte("b"), value)
+	db.HSet([]byte("a"), []byte("1"), value)
+	db.HSet([]byte("b"), []byte("2"), value)
+
+	go slave.Run()
+
+	time.Sleep(1 * time.Second)
+
+	if err = checkDataEqual(master, slave); err != nil {
+		t.Fatal(err)
+	}
+
+	db.Set([]byte("a1"), value)
+	db.Set([]byte("b1"), value)
+	db.HSet([]byte("a1"), []byte("1"), value)
+	db.HSet([]byte("b1"), []byte("2"), value)
+
+	time.Sleep(1 * time.Second)
+	if err = checkDataEqual(master, slave); err != nil {
+		t.Fatal(err)
+	}
+
+	slave.slaveof("")
+
+	db.Set([]byte("a2"), value)
+	db.Set([]byte("b2"), value)
+	db.HSet([]byte("a2"), []byte("1"), value)
+	db.HSet([]byte("b2"), []byte("2"), value)
+
+	db.Set([]byte("a3"), value)
+	db.Set([]byte("b3"), value)
+	db.HSet([]byte("a3"), []byte("1"), value)
+	db.HSet([]byte("b3"), []byte("2"), value)
+
+	if err = checkDataEqual(master, slave); err == nil {
+		t.Fatal("must error")
+	}
+
+	slave.slaveof(masterCfg.Addr)
+	time.Sleep(1 * time.Second)
+
+	if err = checkDataEqual(master, slave); err != nil {
+		t.Fatal(err)
+	}
+
+}

server/config.go

@@ -9,7 +9,16 @@ import (
 type Config struct {
 	Addr string `json:"addr"`
 
+	DataDir string `json:"data_dir"`
+
+	//if you not set db path, use data_dir
 	DB ledis.Config `json:"db"`
+
+	//set slaveof to enable replication from master
+	//empty, no replication
+	SlaveOf string `json:"slaveof"`
+
+	AccessLog string `json:"access_log"`
 }
 
 func NewConfig(data json.RawMessage) (*Config, error) {

server/replication.go

@@ -0,0 +1,325 @@
+package server
+
+import (
+	"bufio"
+	"bytes"
+	"encoding/binary"
+	"encoding/json"
+	"errors"
+	"fmt"
+	"github.com/siddontang/go-log/log"
+	"github.com/siddontang/ledisdb/ledis"
+	"io/ioutil"
+	"net"
+	"os"
+	"path"
+	"strconv"
+	"sync"
+	"time"
+)
+
+var (
+	errConnectMaster = errors.New("connect master error")
+)
+
+type master struct {
+	sync.Mutex
+
+	addr         string `json:"addr"`
+	logFileIndex int64  `json:"log_file_index"`
+	logPos       int64  `json:"log_pos"`
+
+	c  net.Conn
+	rb *bufio.Reader
+
+	app *App
+
+	quit chan struct{}
+
+	infoName    string
+	infoNameBak string
+
+	wg sync.WaitGroup
+
+	syncBuf bytes.Buffer
+}
+
+func newMaster(app *App) *master {
+	m := new(master)
+	m.app = app
+
+	m.infoName = path.Join(m.app.cfg.DataDir, "master.info")
+	m.infoNameBak = fmt.Sprintf("%s.bak", m.infoName)
+
+	m.quit = make(chan struct{}, 1)
+
+	//if load error, we will start a fullsync later
+	m.loadInfo()
+
+	return m
+}
+
+func (m *master) Close() {
+	select {
+	case m.quit <- struct{}{}:
+	default:
+	}
+
+	if m.c != nil {
+		m.c.Close()
+		m.c = nil
+	}
+
+	m.wg.Wait()
+}
+
+func (m *master) loadInfo() error {
+	data, err := ioutil.ReadFile(m.infoName)
+	if err != nil {
+		if os.IsNotExist(err) {
+			return nil
+		} else {
+			return err
+		}
+	}
+
+	if err = json.Unmarshal(data, m); err != nil {
+		return err
+	}
+
+	return nil
+}
+
+func (m *master) saveInfo() error {
+	data, err := json.Marshal(m)
+	if err != nil {
+		return err
+	}
+
+	var fd *os.File
+	fd, err = os.OpenFile(m.infoNameBak, os.O_CREATE|os.O_WRONLY, os.ModePerm)
+	if err != nil {
+		return err
+	}
+
+	if _, err = fd.Write(data); err != nil {
+		fd.Close()
+		return err
+	}
+
+	fd.Close()
+	return os.Rename(m.infoNameBak, m.infoName)
+}
+
+func (m *master) connect() error {
+	if len(m.addr) == 0 {
+		return fmt.Errorf("no assign master addr")
+	}
+
+	if m.c != nil {
+		m.c.Close()
+		m.c = nil
+	}
+
+	if c, err := net.Dial("tcp", m.addr); err != nil {
+		return err
+	} else {
+		m.c = c
+
+		m.rb = bufio.NewReaderSize(m.c, 4096)
+	}
+	return nil
+}
+
+func (m *master) resetInfo(addr string) {
+	m.addr = addr
+	m.logFileIndex = 0
+	m.logPos = 0
+}
+
+func (m *master) stopReplication() error {
+	m.Close()
+
+	if err := m.saveInfo(); err != nil {
+		log.Error("save master info error %s", err.Error())
+		return err
+	}
+
+	return nil
+}
+
+func (m *master) startReplication(masterAddr string) error {
+	//stop last replcation, if avaliable
+	m.Close()
+
+	if masterAddr != m.addr {
+		m.resetInfo(masterAddr)
+		if err := m.saveInfo(); err != nil {
+			log.Error("save master info error %s", err.Error())
+			return err
+		}
+	}
+
+	m.quit = make(chan struct{}, 1)
+
+	go m.runReplication()
+	return nil
+}
+
+func (m *master) runReplication() {
+	m.wg.Add(1)
+	defer m.wg.Done()
+
+	for {
+		select {
+		case <-m.quit:
+			return
+		default:
+			if err := m.connect(); err != nil {
+				log.Error("connect master %s error %s, try 2s later", m.addr, err.Error())
+				time.Sleep(2 * time.Second)
+				continue
+			}
+		}
+
+		if m.logFileIndex == 0 {
+			//try a fullsync
+			if err := m.fullSync(); err != nil {
+				log.Warn("full sync error %s", err.Error())
+				return
+			}
+
+			if m.logFileIndex == 0 {
+				//master not support binlog, we cannot sync, so stop replication
+				m.stopReplication()
+				return
+			}
+		}
+
+		for {
+			for {
+				lastIndex := m.logFileIndex
+				lastPos := m.logPos
+				if err := m.sync(); err != nil {
+					log.Warn("sync error %s", err.Error())
+					return
+				}
+
+				if m.logFileIndex == lastIndex && m.logPos == lastPos {
+					//sync no data, wait 1s and retry
+					break
+				}
+			}
+
+			select {
+			case <-m.quit:
+				return
+			case <-time.After(1 * time.Second):
+				break
+			}
+		}
+	}
+
+	return
+}
+
+var (
+	fullSyncCmd   = []byte("*1\r\n$8\r\nfullsync\r\n")               //fullsync
+	syncCmdFormat = "*3\r\n$4\r\nsync\r\n$%d\r\n%s\r\n$%d\r\n%s\r\n" //sync index pos
+)
+
+func (m *master) fullSync() error {
+	if _, err := m.c.Write(fullSyncCmd); err != nil {
+		return err
+	}
+
+	dumpPath := path.Join(m.app.cfg.DataDir, "master.dump")
+	f, err := os.OpenFile(dumpPath, os.O_CREATE|os.O_WRONLY, os.ModePerm)
+	if err != nil {
+		return err
+	}
+
+	defer os.Remove(dumpPath)
+
+	err = readBulkTo(m.rb, f)
+	f.Close()
+	if err != nil {
+		log.Error("read dump data error %s", err.Error())
+		return err
+	}
+
+	if err = m.app.ldb.FlushAll(); err != nil {
+		return err
+	}
+
+	var head *ledis.MasterInfo
+	head, err = m.app.ldb.LoadDumpFile(dumpPath)
+
+	if err != nil {
+		log.Error("load dump file error %s", err.Error())
+		return err
+	}
+
+	m.logFileIndex = head.LogFileIndex
+	m.logPos = head.LogPos
+
+	return nil
+}
+
+func (m *master) sync() error {
+	logIndexStr := strconv.FormatInt(m.logFileIndex, 10)
+	logPosStr := strconv.FormatInt(m.logPos, 10)
+
+	cmd := ledis.Slice(fmt.Sprintf(syncCmdFormat, len(logIndexStr),
+		logIndexStr, len(logPosStr), logPosStr))
+	if _, err := m.c.Write(cmd); err != nil {
+		return err
+	}
+
+	m.syncBuf.Reset()
+
+	err := readBulkTo(m.rb, &m.syncBuf)
+	if err != nil {
+		return err
+	}
+
+	err = binary.Read(&m.syncBuf, binary.BigEndian, &m.logFileIndex)
+	if err != nil {
+		return err
+	}
+
+	err = binary.Read(&m.syncBuf, binary.BigEndian, &m.logPos)
+	if err != nil {
+		return err
+	}
+
+	if m.logFileIndex == 0 {
+		//master now not support binlog, stop replication
+		m.stopReplication()
+		return nil
+	} else if m.logFileIndex == -1 {
+		//-1 means than binlog index and pos are lost, we must start a full sync instead
+		return m.fullSync()
+	}
+
+	err = m.app.ldb.ReplicateFromReader(&m.syncBuf)
+	if err != nil {
+		return err
+	}
+
+	return nil
+
+}
+
+func (app *App) slaveof(masterAddr string) error {
+	app.m.Lock()
+	defer app.m.Unlock()
+
+	if len(masterAddr) == 0 {
+		return app.m.stopReplication()
+	} else {
+		return app.m.startReplication(masterAddr)
+	}
+
+	return nil
+}

server/util.go

@@ -0,0 +1,57 @@
+package server
+
+import (
+	"bufio"
+	"errors"
+	"github.com/siddontang/ledisdb/ledis"
+	"io"
+	"strconv"
+)
+
+var (
+	errArrayFormat = errors.New("bad array format")
+	errBulkFormat  = errors.New("bad bulk string format")
+	errLineFormat  = errors.New("bad response line format")
+)
+
+func readLine(rb *bufio.Reader) ([]byte, error) {
+	p, err := rb.ReadSlice('\n')
+
+	if err != nil {
+		return nil, err
+	}
+	i := len(p) - 2
+	if i < 0 || p[i] != '\r' {
+		return nil, errLineFormat
+	}
+	return p[:i], nil
+}
+
+func readBulkTo(rb *bufio.Reader, w io.Writer) error {
+	l, err := readLine(rb)
+	if len(l) == 0 {
+		return errBulkFormat
+	} else if l[0] == '$' {
+		var n int
+		//handle resp string
+		if n, err = strconv.Atoi(ledis.String(l[1:])); err != nil {
+			return err
+		} else if n == -1 {
+			return nil
+		} else {
+			if _, err = io.CopyN(w, rb, int64(n)); err != nil {
+				return err
+			}
+
+			if l, err = readLine(rb); err != nil {
+				return err
+			} else if len(l) != 0 {
+				return errBulkFormat
+			}
+		}
+	} else {
+		return errBulkFormat
+	}
+
+	return nil
+}