refactor flush db

database/single_db.go

@@ -10,7 +10,6 @@ import (
 	"github.com/hdt3213/godis/lib/timewheel"
 	"github.com/hdt3213/godis/redis/protocol"
 	"strings"
-	"sync"
 	"time"
 )
 
@@ -33,9 +32,7 @@ type DB struct {
 	// dict.Dict will ensure concurrent-safety of its method
 	// use this mutex for complicated command only, eg. rpush, incr ...
 	locker *lock.Locks
-	// stop all data access for execFlushDB
-	stopWorld sync.WaitGroup
-	addAof    func(CmdLine)
+	addAof func(CmdLine)
 }
 
 // ExecFunc is interface for command executor
@@ -102,14 +99,6 @@ func (db *DB) Exec(c redis.Connection, cmdLine [][]byte) redis.Reply {
 			return protocol.MakeArgNumErrReply(cmdName)
 		}
 		return Watch(db, c, cmdLine[1:])
-	} else if cmdName == "flushdb" {
-		if !validateArity(1, cmdLine) {
-			return protocol.MakeArgNumErrReply(cmdName)
-		}
-		if c.InMultiState() {
-			return protocol.MakeErrReply("ERR command 'FlushDB' cannot be used in MULTI")
-		}
-		return execFlushDB(db, cmdLine[1:])
 	}
 	if c != nil && c.InMultiState() {
 		EnqueueCmd(c, cmdLine)
@@ -164,8 +153,6 @@ func validateArity(arity int, cmdArgs [][]byte) bool {
 
 // GetEntity returns DataEntity bind to given key
 func (db *DB) GetEntity(key string) (*database.DataEntity, bool) {
-	db.stopWorld.Wait()
-
 	raw, ok := db.data.Get(key)
 	if !ok {
 		return nil, false
@@ -179,25 +166,21 @@ func (db *DB) GetEntity(key string) (*database.DataEntity, bool) {
 
 // PutEntity a DataEntity into DB
 func (db *DB) PutEntity(key string, entity *database.DataEntity) int {
-	db.stopWorld.Wait()
 	return db.data.Put(key, entity)
 }
 
 // PutIfExists edit an existing DataEntity
 func (db *DB) PutIfExists(key string, entity *database.DataEntity) int {
-	db.stopWorld.Wait()
 	return db.data.PutIfExists(key, entity)
 }
 
 // PutIfAbsent insert an DataEntity only if the key not exists
 func (db *DB) PutIfAbsent(key string, entity *database.DataEntity) int {
-	db.stopWorld.Wait()
 	return db.data.PutIfAbsent(key, entity)
 }
 
 // Remove the given key from db
 func (db *DB) Remove(key string) {
-	db.stopWorld.Wait()
 	db.data.Remove(key)
 	db.ttlMap.Remove(key)
 	taskKey := genExpireTask(key)
@@ -206,7 +189,6 @@ func (db *DB) Remove(key string) {
 
 // Removes the given keys from db
 func (db *DB) Removes(keys ...string) (deleted int) {
-	db.stopWorld.Wait()
 	deleted = 0
 	for _, key := range keys {
 		_, exists := db.data.Get(key)
@@ -219,24 +201,14 @@ func (db *DB) Removes(keys ...string) (deleted int) {
 }
 
 // Flush clean database
+// deprecated
+// for test only
 func (db *DB) Flush() {
-	db.stopWorld.Add(1)
-	defer db.stopWorld.Done()
-
 	db.data.Clear()
 	db.ttlMap.Clear()
 	db.locker = lock.Make(lockerSize)
 }
 
-func (db *DB) Load(db2 *DB) {
-	db.stopWorld.Add(1)
-	defer db.stopWorld.Done()
-
-	db.data = db2.data
-	db.ttlMap = db2.ttlMap
-	db.locker = lock.Make(lockerSize)
-}
-
 /* ---- Lock Function ----- */
 
 // RWLocks lock keys for writing and reading
@@ -257,7 +229,6 @@ func genExpireTask(key string) string {
 
 // Expire sets ttlCmd of key
 func (db *DB) Expire(key string, expireTime time.Time) {
-	db.stopWorld.Wait()
 	db.ttlMap.Put(key, expireTime)
 	taskKey := genExpireTask(key)
 	timewheel.At(expireTime, taskKey, func() {
@@ -280,7 +251,6 @@ func (db *DB) Expire(key string, expireTime time.Time) {
 
 // Persist cancel ttlCmd of key
 func (db *DB) Persist(key string) {
-	db.stopWorld.Wait()
 	db.ttlMap.Remove(key)
 	taskKey := genExpireTask(key)
 	timewheel.Cancel(taskKey)
@@ -288,7 +258,6 @@ func (db *DB) Persist(key string) {
 
 // IsExpired check whether a key is expired
 func (db *DB) IsExpired(key string) bool {
-	db.stopWorld.Wait()
 	rawExpireTime, ok := db.ttlMap.Get(key)
 	if !ok {
 		return false
@@ -304,7 +273,6 @@ func (db *DB) IsExpired(key string) bool {
 /* --- add version --- */
 
 func (db *DB) addVersion(keys ...string) {
-	db.stopWorld.Wait()
 	for _, key := range keys {
 		versionCode := db.GetVersion(key)
 		db.versionMap.Put(key, versionCode+1)
@@ -313,7 +281,6 @@ func (db *DB) addVersion(keys ...string) {
 
 // GetVersion returns version code for given key
 func (db *DB) GetVersion(key string) uint32 {
-	db.stopWorld.Wait()
 	entity, ok := db.versionMap.Get(key)
 	if !ok {
 		return 0
@@ -323,7 +290,6 @@ func (db *DB) GetVersion(key string) uint32 {
 
 // ForEach traverses all the keys in the database
 func (db *DB) ForEach(cb func(key string, data *database.DataEntity, expiration *time.Time) bool) {
-	db.stopWorld.Wait()
 	db.data.ForEach(func(key string, raw interface{}) bool {
 		entity, _ := raw.(*database.DataEntity)
 		var expiration *time.Time