readd transaction

client/ledis-py/ledis/client.py

@@ -9,7 +9,8 @@ from ledis.exceptions import (
     ConnectionError,
     DataError,
     LedisError,
-    ResponseError
+    ResponseError,
+    TxNotBeginError
 )
 
 SYM_EMPTY = b('')
@@ -199,6 +200,11 @@ class Ledis(object):
         "Set a custom Response Callback"
         self.response_callbacks[command] = callback
 
+    def tx(self):
+        return Transaction(
+            self.connection_pool,
+            self.response_callbacks)
+
     #### COMMAND EXECUTION AND PROTOCOL PARSING ####
 
     def execute_command(self, *args, **options):
@@ -964,3 +970,43 @@ class Ledis(object):
 
     def scriptflush(self):
         return self.execute_command('SCRIPT', 'FLUSH')
+
+
+class Transaction(Ledis):
+    def __init__(self, connection_pool, response_callbacks):
+        self.connection_pool = connection_pool
+        self.response_callbacks = response_callbacks
+        self.connection = None
+
+    def execute_command(self, *args, **options):
+        "Execute a command and return a parsed response"
+        command_name = args[0]
+
+        connection = self.connection
+        if self.connection is None:
+            raise TxNotBeginError
+
+        try:
+            connection.send_command(*args)
+            return self.parse_response(connection, command_name, **options)
+        except ConnectionError:
+            connection.disconnect()
+            connection.send_command(*args)
+            return self.parse_response(connection, command_name, **options)
+
+    def begin(self):
+        self.connection = self.connection_pool.get_connection('begin')
+        return self.execute_command("BEGIN")
+
+    def commit(self):
+        res = self.execute_command("COMMIT")
+        self.connection_pool.release(self.connection)
+        self.connection = None
+        return res
+
+    def rollback(self):
+        res = self.execute_command("ROLLBACK")
+        self.connection_pool.release(self.connection)
+        self.connection = None
+        return res
+

client/ledis-py/ledis/exceptions.py

@@ -35,3 +35,5 @@ class DataError(LedisError):
 class ExecAbortError(ResponseError):
     pass
 
+class TxNotBeginError(LedisError):
+    pass

client/ledis-py/tests/test_tx.py

@@ -0,0 +1,46 @@
+import unittest
+import sys
+sys.path.append("..")
+
+import ledis
+
+global_l = ledis.Ledis()
+
+#db that do not support transaction
+dbs = ["leveldb", "rocksdb", "hyperleveldb", "goleveldb"]
+check = global_l.info().get("db_name") in dbs
+
+
+class TestTx(unittest.TestCase):
+    def setUp(self):
+        self.l = ledis.Ledis(port=6380)
+
+    def tearDown(self):
+        self.l.flushdb()
+    
+    @unittest.skipIf(check, reason="db not support transaction")
+    def test_commit(self):
+        tx = self.l.tx()
+        self.l.set("a", "no-tx")
+        assert self.l.get("a") == "no-tx"
+        tx.begin()
+        tx.set("a", "tx")
+        assert self.l.get("a") == "no-tx"
+        assert tx.get("a") == "tx"
+
+        tx.commit()
+        assert self.l.get("a") == "tx"
+
+    @unittest.skipIf(check, reason="db not support transaction")
+    def test_rollback(self):
+        tx = self.l.tx()
+        self.l.set("a", "no-tx")
+        assert self.l.get("a") == "no-tx"
+
+        tx.begin()
+        tx.set("a", "tx")
+        assert tx.get("a") == "tx"
+        assert self.l.get("a") == "no-tx"
+
+        tx.rollback()
+        assert self.l.get("a") == "no-tx"

client/nodejs/ledis/lib/commands.js

@@ -125,6 +125,10 @@ module.exports = [
 	"spersist",
 	"sxscan",
 
+    "begin",
+    "rollback",
+    "commit",
+    
     "eval",
     "evalsha",
     "script",

client/openresty/ledis.lua

@@ -148,6 +148,11 @@ local commands = {
     "flushall",
     "flushdb",
 
+    -- [[transaction]]
+    "begin",
+    "commit",
+    "rollback",
+
     -- [[script]]
     "eval",
     "evalsha",

cmd/ledis-cli/const.go

@@ -1,9 +1,10 @@
-//This file was generated by .tools/generate_commands.py on Tue Sep 09 2014 09:48:57 +0800
+//This file was generated by .tools/generate_commands.py on Thu Sep 25 2014 09:51:10 +0800 
 package main
 
 var helpCommands = [][]string{
 	{"BCOUNT", "key [start end]", "Bitmap"},
 	{"BDELETE", "key", "ZSet"},
+	{"BEGIN", "-", "Transaction"},
 	{"BEXPIRE", "key seconds", "Bitmap"},
 	{"BEXPIREAT", "key timestamp", "Bitmap"},
 	{"BGET", "key", "Bitmap"},
@@ -14,6 +15,7 @@ var helpCommands = [][]string{
 	{"BSETBIT", "key offset value", "Bitmap"},
 	{"BTTL", "key", "Bitmap"},
 	{"BXSCAN", "key [MATCH match] [COUNT count]", "Bitmap"},
+	{"COMMIT", "-", "Transaction"},
 	{"DECR", "key", "KV"},
 	{"DECRBY", "key decrement", "KV"},
 	{"DEL", "key [key ...]", "KV"},
@@ -65,6 +67,7 @@ var helpCommands = [][]string{
 	{"MSET", "key value [key value ...]", "KV"},
 	{"PERSIST", "key", "KV"},
 	{"PING", "-", "Server"},
+	{"ROLLBACK", "-", "Transaction"},
 	{"RPOP", "key", "List"},
 	{"RPUSH", "key value [value ...]", "List"},
 	{"SADD", "key member [member ...]", "Set"},

doc/DiffRedis.md

@@ -35,6 +35,15 @@ The same for Del.
 
 ZSet only support int64 score, not double in Redis.
 
+## Transaction
+
+LedisDB supports ACID transaction using LMDB or BoltDB, maybe later it will support `multi`, `exec`, `discard`.
+
+Transaction API:
+
++ `begin`
++ `commit`
++ `rollback`
 
 ## Scan
 

doc/commands.json

@@ -512,6 +512,22 @@
         "readonly": false
     },
 
+    "BEGIN": {
+        "arguments": "-",
+        "group": "Transaction",
+        "readonly": false
+    },
+    "COMMIT": {
+        "arguments": "-",
+        "group": "Transaction",
+        "readonly": false
+    },
+    "ROLLBACK": {
+        "arguments": "-",
+        "group": "Transaction",
+        "readonly": false
+    },
+
     "XSCAN": {
         "arguments": "key [MATCH match] [COUNT count]",
         "group": "KV",

doc/commands.md

@@ -129,6 +129,10 @@ Table of Contents
 	- [FLUSHALL](#flushall)
 	- [FLUSHDB](#flushdb)
 	- [INFO [section]](#info-section)
+- [Transaction](#transaction)
+	- [BEGIN](#begin)
+	- [ROLLBACK](#rollback)
+	- [COMMIT](#commit)
 - [Script](#script)
 	- [EVAL script numkeys key [key ...] arg [arg ...]](#eval-script-numkeys-key-key--arg-arg-)
 	- [EVALSHA sha1 numkeys key [key ...] arg [arg ...]](#evalsha-sha1-numkeys-key-key--arg-arg-)
@@ -2498,6 +2502,69 @@ The optional parameter can be used to select a specific section of information:
 
 When no parameter is provided, all will return.
 
+## Transaction
+
+### BEGIN
+
+Marks the start of a transaction block. Subsequent commands will be in a transaction context util using COMMIT or ROLLBACK.
+
+You must known that `BEGIN` will block any other write operators before you `COMMIT` or `ROLLBACK`. Don't use long-time transaction.
+
+**Return value**
+
+Returns `OK` if the backend store engine in use supports transaction, otherwise, returns `Err`. 
+
+**Examples**
+```
+ledis> BEGIN
+OK
+ledis> SET HELLO WORLD
+OK
+ledis> COMMIT
+OK
+```
+
+### ROLLBACK
+
+Discards all the changes of previously commands in a transaction and restores the connection state to normal.
+
+**Return value**
+Returns `OK` if in a transaction context, otherwise, `Err`
+
+**Examples**
+```
+ledis> BEGIN
+OK
+ledis> SET HELLO WORLD
+OK
+ledis> GET HELLO
+"WORLD"
+ledis> ROLLBACK
+OK
+ledis> GET HELLO
+(nil)
+```
+
+### COMMIT
+
+Persists the changes of all the commands in a transaction and restores the connection state to normal.
+
+**Return value**
+Returns `OK` if in a transaction context, otherwise, `Err`
+
+**Examples**
+```
+ledis> BEGIN
+OK
+ledis> SET HELLO WORLD
+OK
+ledis> GET HELLO
+"WORLD"
+ledis> COMMIT
+OK
+ledis> GET HELLO
+"WORLD"
+```
 
 ## Script
 

ledis/batch.go

@@ -14,6 +14,8 @@ type batch struct {
 
 	sync.Locker
 
+	tx *Tx
+
 	eb *eventBatch
 }
 
@@ -22,31 +24,12 @@ func (b *batch) Commit() error {
 		return ErrWriteInROnly
 	}
 
-	b.l.commitLock.Lock()
-	defer b.l.commitLock.Unlock()
-
-	var err error
-	if b.l.r != nil {
-		var l *rpl.Log
-		if l, err = b.l.r.Log(b.eb.Bytes()); err != nil {
-			log.Fatal("write wal error %s", err.Error())
-			return err
-		}
-
-		b.l.propagate(l)
-
-		if err = b.WriteBatch.Commit(); err != nil {
-			log.Fatal("commit error %s", err.Error())
-			return err
-		}
-
-		if err = b.l.r.UpdateCommitID(l.ID); err != nil {
-			log.Fatal("update commit id error %s", err.Error())
-			return err
-		}
-
-		return nil
+	if b.tx == nil {
+		return b.l.handleCommit(b.eb, b.WriteBatch)
 	} else {
+		if b.l.r != nil {
+			b.tx.eb.Write(b.eb.Bytes())
+		}
 		return b.WriteBatch.Commit()
 	}
 }
@@ -93,20 +76,61 @@ func (l *dbBatchLocker) Unlock() {
 	l.wrLock.RUnlock()
 }
 
+type txBatchLocker struct {
+}
+
+func (l *txBatchLocker) Lock()   {}
+func (l *txBatchLocker) Unlock() {}
+
 type multiBatchLocker struct {
 }
 
 func (l *multiBatchLocker) Lock()   {}
 func (l *multiBatchLocker) Unlock() {}
 
-func (l *Ledis) newBatch(wb store.WriteBatch, locker sync.Locker) *batch {
+func (l *Ledis) newBatch(wb store.WriteBatch, locker sync.Locker, tx *Tx) *batch {
 	b := new(batch)
 	b.l = l
 	b.WriteBatch = wb
 
 	b.Locker = locker
 
+	b.tx = tx
 	b.eb = new(eventBatch)
 
 	return b
 }
+
+type commiter interface {
+	Commit() error
+}
+
+func (l *Ledis) handleCommit(eb *eventBatch, c commiter) error {
+	l.commitLock.Lock()
+	defer l.commitLock.Unlock()
+
+	var err error
+	if l.r != nil {
+		var rl *rpl.Log
+		if rl, err = l.r.Log(eb.Bytes()); err != nil {
+			log.Fatal("write wal error %s", err.Error())
+			return err
+		}
+
+		l.propagate(rl)
+
+		if err = c.Commit(); err != nil {
+			log.Fatal("commit error %s", err.Error())
+			return err
+		}
+
+		if err = l.r.UpdateCommitID(rl.ID); err != nil {
+			log.Fatal("update commit id error %s", err.Error())
+			return err
+		}
+
+		return nil
+	} else {
+		return c.Commit()
+	}
+}

ledis/const.go

@@ -92,6 +92,7 @@ var (
 )
 
 const (
-	DBAutoCommit uint8 = 0x0
-	DBInMulti    uint8 = 0x2
+	DBAutoCommit    uint8 = 0x0
+	DBInTransaction uint8 = 0x1
+	DBInMulti       uint8 = 0x2
 )

ledis/ledis_db.go

@@ -64,7 +64,7 @@ func (l *Ledis) newDB(index uint8) *DB {
 }
 
 func (db *DB) newBatch() *batch {
-	return db.l.newBatch(db.bucket.NewWriteBatch(), &dbBatchLocker{l: &sync.Mutex{}, wrLock: &db.l.wLock})
+	return db.l.newBatch(db.bucket.NewWriteBatch(), &dbBatchLocker{l: &sync.Mutex{}, wrLock: &db.l.wLock}, nil)
 }
 
 func (db *DB) Index() int {

ledis/multi.go

@@ -51,7 +51,7 @@ func (db *DB) Multi() (*Multi, error) {
 }
 
 func (m *Multi) newBatch() *batch {
-	return m.l.newBatch(m.bucket.NewWriteBatch(), &multiBatchLocker{})
+	return m.l.newBatch(m.bucket.NewWriteBatch(), &multiBatchLocker{}, nil)
 }
 
 func (m *Multi) Close() error {

ledis/tx.go

@@ -0,0 +1,109 @@
+package ledis
+
+import (
+	"errors"
+	"fmt"
+	"github.com/siddontang/ledisdb/store"
+)
+
+var (
+	ErrNestTx = errors.New("nest transaction not supported")
+	ErrTxDone = errors.New("Transaction has already been committed or rolled back")
+)
+
+type Tx struct {
+	*DB
+
+	tx *store.Tx
+
+	eb *eventBatch
+}
+
+func (db *DB) IsTransaction() bool {
+	return db.status == DBInTransaction
+}
+
+// Begin a transaction, it will block all other write operations before calling Commit or Rollback.
+// You must be very careful to prevent long-time transaction.
+func (db *DB) Begin() (*Tx, error) {
+	if db.IsTransaction() {
+		return nil, ErrNestTx
+	}
+
+	tx := new(Tx)
+
+	tx.eb = new(eventBatch)
+
+	tx.DB = new(DB)
+	tx.DB.l = db.l
+
+	tx.l.wLock.Lock()
+
+	tx.DB.sdb = db.sdb
+
+	var err error
+	tx.tx, err = db.sdb.Begin()
+	if err != nil {
+		tx.l.wLock.Unlock()
+		return nil, err
+	}
+
+	tx.DB.bucket = tx.tx
+
+	tx.DB.status = DBInTransaction
+
+	tx.DB.index = db.index
+
+	tx.DB.kvBatch = tx.newBatch()
+	tx.DB.listBatch = tx.newBatch()
+	tx.DB.hashBatch = tx.newBatch()
+	tx.DB.zsetBatch = tx.newBatch()
+	tx.DB.binBatch = tx.newBatch()
+	tx.DB.setBatch = tx.newBatch()
+
+	return tx, nil
+}
+
+func (tx *Tx) Commit() error {
+	if tx.tx == nil {
+		return ErrTxDone
+	}
+
+	err := tx.l.handleCommit(tx.eb, tx.tx)
+
+	tx.tx = nil
+
+	tx.l.wLock.Unlock()
+
+	tx.DB.bucket = nil
+
+	return err
+}
+
+func (tx *Tx) Rollback() error {
+	if tx.tx == nil {
+		return ErrTxDone
+	}
+
+	err := tx.tx.Rollback()
+	tx.eb.Reset()
+	tx.tx = nil
+
+	tx.l.wLock.Unlock()
+	tx.DB.bucket = nil
+
+	return err
+}
+
+func (tx *Tx) newBatch() *batch {
+	return tx.l.newBatch(tx.tx.NewWriteBatch(), &txBatchLocker{}, tx)
+}
+
+func (tx *Tx) Select(index int) error {
+	if index < 0 || index >= int(MaxDBNumber) {
+		return fmt.Errorf("invalid db index %d", index)
+	}
+
+	tx.DB.index = uint8(index)
+	return nil
+}

ledis/tx_test.go

@@ -0,0 +1,220 @@
+package ledis
+
+import (
+	"github.com/siddontang/ledisdb/config"
+	"os"
+	"testing"
+)
+
+func testTxRollback(t *testing.T, db *DB) {
+	var err error
+	key1 := []byte("tx_key1")
+	key2 := []byte("tx_key2")
+	field2 := []byte("tx_field2")
+
+	err = db.Set(key1, []byte("value"))
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	_, err = db.HSet(key2, field2, []byte("value"))
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	var tx *Tx
+	tx, err = db.Begin()
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	defer tx.Rollback()
+
+	err = tx.Set(key1, []byte("1"))
+
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	_, err = tx.HSet(key2, field2, []byte("2"))
+
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	_, err = tx.HSet([]byte("no_key"), field2, []byte("2"))
+
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	if v, err := tx.Get(key1); err != nil {
+		t.Fatal(err)
+	} else if string(v) != "1" {
+		t.Fatal(string(v))
+	}
+
+	if v, err := tx.HGet(key2, field2); err != nil {
+		t.Fatal(err)
+	} else if string(v) != "2" {
+		t.Fatal(string(v))
+	}
+
+	err = tx.Rollback()
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	if v, err := db.Get(key1); err != nil {
+		t.Fatal(err)
+	} else if string(v) != "value" {
+		t.Fatal(string(v))
+	}
+
+	if v, err := db.HGet(key2, field2); err != nil {
+		t.Fatal(err)
+	} else if string(v) != "value" {
+		t.Fatal(string(v))
+	}
+}
+
+func testTxCommit(t *testing.T, db *DB) {
+	var err error
+	key1 := []byte("tx_key1")
+	key2 := []byte("tx_key2")
+	field2 := []byte("tx_field2")
+
+	err = db.Set(key1, []byte("value"))
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	_, err = db.HSet(key2, field2, []byte("value"))
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	var tx *Tx
+	tx, err = db.Begin()
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	defer tx.Rollback()
+
+	err = tx.Set(key1, []byte("1"))
+
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	_, err = tx.HSet(key2, field2, []byte("2"))
+
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	if v, err := tx.Get(key1); err != nil {
+		t.Fatal(err)
+	} else if string(v) != "1" {
+		t.Fatal(string(v))
+	}
+
+	if v, err := tx.HGet(key2, field2); err != nil {
+		t.Fatal(err)
+	} else if string(v) != "2" {
+		t.Fatal(string(v))
+	}
+
+	err = tx.Commit()
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	if v, err := db.Get(key1); err != nil {
+		t.Fatal(err)
+	} else if string(v) != "1" {
+		t.Fatal(string(v))
+	}
+
+	if v, err := db.HGet(key2, field2); err != nil {
+		t.Fatal(err)
+	} else if string(v) != "2" {
+		t.Fatal(string(v))
+	}
+}
+
+func testTxSelect(t *testing.T, db *DB) {
+	tx, err := db.Begin()
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	defer tx.Rollback()
+
+	tx.Set([]byte("tx_select_1"), []byte("a"))
+
+	tx.Select(1)
+
+	tx.Set([]byte("tx_select_2"), []byte("b"))
+
+	if err = tx.Commit(); err != nil {
+		t.Fatal(err)
+	}
+
+	if v, err := db.Get([]byte("tx_select_1")); err != nil {
+		t.Fatal(err)
+	} else if string(v) != "a" {
+		t.Fatal(string(v))
+	}
+
+	if v, err := db.Get([]byte("tx_select_2")); err != nil {
+		t.Fatal(err)
+	} else if v != nil {
+		t.Fatal("must nil")
+	}
+
+	db, _ = db.l.Select(1)
+
+	if v, err := db.Get([]byte("tx_select_2")); err != nil {
+		t.Fatal(err)
+	} else if string(v) != "b" {
+		t.Fatal(string(v))
+	}
+
+	if v, err := db.Get([]byte("tx_select_1")); err != nil {
+		t.Fatal(err)
+	} else if v != nil {
+		t.Fatal("must nil")
+	}
+}
+
+func testTx(t *testing.T, name string) {
+	cfg := new(config.Config)
+	cfg.DataDir = "/tmp/ledis_test_tx"
+
+	cfg.DBName = name
+	cfg.LMDB.MapSize = 10 * 1024 * 1024
+	cfg.UseReplication = true
+
+	os.RemoveAll(cfg.DataDir)
+
+	l, err := Open(cfg)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	defer l.Close()
+
+	db, _ := l.Select(0)
+
+	testTxRollback(t, db)
+	testTxCommit(t, db)
+	testTxSelect(t, db)
+}
+
+//only lmdb, boltdb support Transaction
+func TestTx(t *testing.T) {
+	testTx(t, "lmdb")
+	testTx(t, "boltdb")
+}

server/client.go

@@ -8,10 +8,24 @@ import (
 	"time"
 )
 
+var txUnsupportedCmds = map[string]struct{}{
+	"select":   struct{}{},
+	"slaveof":  struct{}{},
+	"fullsync": struct{}{},
+	"sync":     struct{}{},
+	"begin":    struct{}{},
+	"flushall": struct{}{},
+	"flushdb":  struct{}{},
+	"eval":     struct{}{},
+}
+
 var scriptUnsupportedCmds = map[string]struct{}{
 	"slaveof":  struct{}{},
 	"fullsync": struct{}{},
 	"sync":     struct{}{},
+	"begin":    struct{}{},
+	"commit":   struct{}{},
+	"rollback": struct{}{},
 	"flushall": struct{}{},
 	"flushdb":  struct{}{},
 }
@@ -57,6 +71,8 @@ type client struct {
 
 	buf bytes.Buffer
 
+	tx *ledis.Tx
+
 	script *ledis.Multi
 }
 
@@ -83,7 +99,11 @@ func (c *client) perform() {
 	} else if exeCmd, ok := regCmds[c.cmd]; !ok {
 		err = ErrNotFound
 	} else {
-		if c.db.IsInMulti() {
+		if c.db.IsTransaction() {
+			if _, ok := txUnsupportedCmds[c.cmd]; ok {
+				err = fmt.Errorf("%s not supported in transaction", c.cmd)
+			}
+		} else if c.db.IsInMulti() {
 			if _, ok := scriptUnsupportedCmds[c.cmd]; ok {
 				err = fmt.Errorf("%s not supported in multi", c.cmd)
 			}

server/client_http.go

@@ -24,6 +24,9 @@ var httpUnsupportedCommands = map[string]struct{}{
 	"fullsync": struct{}{},
 	"sync":     struct{}{},
 	"quit":     struct{}{},
+	"begin":    struct{}{},
+	"commit":   struct{}{},
+	"rollback": struct{}{},
 }
 
 type httpClient struct {

server/cmd_tx.go

@@ -0,0 +1,57 @@
+package server
+
+import (
+	"errors"
+)
+
+var errTxMiss = errors.New("transaction miss")
+
+func beginCommand(c *client) error {
+	tx, err := c.db.Begin()
+	if err == nil {
+		c.tx = tx
+		c.db = tx.DB
+		c.resp.writeStatus(OK)
+	}
+
+	return err
+}
+
+func commitCommand(c *client) error {
+	if c.tx == nil {
+		return errTxMiss
+	}
+
+	err := c.tx.Commit()
+	c.db, _ = c.ldb.Select(c.tx.Index())
+	c.tx = nil
+
+	if err == nil {
+		c.resp.writeStatus(OK)
+	}
+
+	return err
+}
+
+func rollbackCommand(c *client) error {
+	if c.tx == nil {
+		return errTxMiss
+	}
+
+	err := c.tx.Rollback()
+
+	c.db, _ = c.ldb.Select(c.tx.Index())
+	c.tx = nil
+
+	if err == nil {
+		c.resp.writeStatus(OK)
+	}
+
+	return err
+}
+
+func init() {
+	register("begin", beginCommand)
+	register("commit", commitCommand)
+	register("rollback", rollbackCommand)
+}