diff --git a/broker/broker.go b/broker/broker.go
index cf772c9..8d51929 100644
--- a/broker/broker.go
+++ b/broker/broker.go
@@ -2,13 +2,13 @@ package broker
 
 import (
 	"crypto/tls"
+	encJson "encoding/json"
 	"errors"
 	"fmt"
 	"net"
 	"net/http"
 	"sync"
 	"time"
-	encJson "encoding/json"
 
 	"github.com/fhmq/hmq/broker/lib/sessions"
 	"github.com/fhmq/hmq/broker/lib/topics"
@@ -205,8 +205,8 @@ func (b *Broker) StartWebsocketListening() {
 func (b *Broker) wsHandler(ws *websocket.Conn) {
 	// io.Copy(ws, ws)
 	ws.PayloadType = websocket.BinaryFrame
-	err:=b.handleConnection(CLIENT, ws)
-	if err!=nil{
+	err := b.handleConnection(CLIENT, ws)
+	if err != nil {
 		ws.Close()
 	}
 }
@@ -259,9 +259,9 @@ func (b *Broker) StartClientListening(Tls bool) {
 		}
 
 		tmpDelay = ACCEPT_MIN_SLEEP
-		go func(){
-			err :=b.handleConnection(CLIENT, conn)
-			if err!=nil{
+		go func() {
+			err := b.handleConnection(CLIENT, conn)
+			if err != nil {
 				conn.Close()
 			}
 		}()
@@ -301,9 +301,9 @@ func (b *Broker) StartClusterListening() {
 		}
 		tmpDelay = ACCEPT_MIN_SLEEP
 
-		go func(){
-			err :=b.handleConnection(ROUTER, conn)
-			if err!=nil{
+		go func() {
+			err := b.handleConnection(ROUTER, conn)
+			if err != nil {
 				conn.Close()
 			}
 		}()
@@ -322,11 +322,11 @@ func (b *Broker) DisConnClientByClientId(clientId string) {
 	conn.Close()
 }
 
-func (b *Broker) handleConnection(typ int, conn net.Conn) error{
+func (b *Broker) handleConnection(typ int, conn net.Conn) error {
 	//process connect packet
 	packet, err := packets.ReadPacket(conn)
 	if err != nil {
-		return errors.New(fmt.Sprintln("read connect packet error:%v",err))
+		return errors.New(fmt.Sprintf("read connect packet error:%v", err))
 	}
 	if packet == nil {
 		return errors.New("received nil packet")
@@ -344,21 +344,21 @@ func (b *Broker) handleConnection(typ int, conn net.Conn) error{
 
 	if connack.ReturnCode != packets.Accepted {
 		if err := connack.Write(conn); err != nil {
-			return errors.New(fmt.Sprintln("send connack error:%v,clientID:%v,conn:%v",err,msg.ClientIdentifier,conn))
+			return fmt.Errorf("send connack error:%v,clientID:%v,conn:%v", err, msg.ClientIdentifier, conn)
 		}
-		return errors.New(fmt.Sprintln("connect packet validate failed with connack.ReturnCode%v",connack.ReturnCode))
+		return fmt.Errorf("connect packet validate failed with connack.ReturnCode%v", connack.ReturnCode)
 	}
 
 	if typ == CLIENT && !b.CheckConnectAuth(msg.ClientIdentifier, msg.Username, string(msg.Password)) {
 		connack.ReturnCode = packets.ErrRefusedNotAuthorised
 		if err := connack.Write(conn); err != nil {
-			return errors.New(fmt.Sprintln("send connack error:%v,clientID:%v,conn:%v",err,msg.ClientIdentifier,conn))
+			return fmt.Errorf("send connack error:%v,clientID:%v,conn:%v", err, msg.ClientIdentifier, conn)
 		}
-		return errors.New(fmt.Sprintln("connect packet CheckConnectAuth failed with connack.ReturnCode%v",connack.ReturnCode))
+		return fmt.Errorf("connect packet CheckConnectAuth failed with connack.ReturnCode%v", connack.ReturnCode)
 	}
 
 	if err := connack.Write(conn); err != nil {
-		return errors.New(fmt.Sprintln("send connack error:%v,clientID:%v,conn:%v",err,msg.ClientIdentifier,conn))
+		return fmt.Errorf("send connack error:%v,clientID:%v,conn:%v", err, msg.ClientIdentifier, conn)
 	}
 
 	willmsg := packets.NewControlPacket(packets.Publish).(*packets.PublishPacket)
@@ -389,7 +389,7 @@ func (b *Broker) handleConnection(typ int, conn net.Conn) error{
 	c.init()
 
 	if err := b.getSession(c, msg, connack); err != nil {
-		return errors.New(fmt.Sprintln("get session error:%v,clientID:%v,conn:%v",err,msg.ClientIdentifier,conn))
+		return fmt.Errorf("get session error:%v,clientID:%v,conn:%v", err, msg.ClientIdentifier, conn)
 	}
 
 	cid := c.info.clientID
@@ -413,13 +413,13 @@ func (b *Broker) handleConnection(typ int, conn net.Conn) error{
 			pubPack.TopicName = info.willMsg.TopicName
 			pubPack.Payload = info.willMsg.Payload
 		}
-		
+
 		pubInfo := Info{
-			ClientID: info.clientID,
-			Username: info.username,
-			Password: info.password,
+			ClientID:  info.clientID,
+			Username:  info.username,
+			Password:  info.password,
 			Keepalive: info.keepalive,
-			WillMsg: pubPack,
+			WillMsg:   pubPack,
 		}
 
 		b.OnlineOfflineNotification(pubInfo, true, c.lastMsgTime)
@@ -456,7 +456,7 @@ func (b *Broker) ConnectToDiscovery() {
 			log.Error("Error trying to connect to route", zap.Error(err))
 			log.Debug("Connect to route timeout, retry...")
 
-			if 0 == tempDelay {
+			if tempDelay == 0 {
 				tempDelay = 1 * time.Second
 			} else {
 				tempDelay *= 2
@@ -528,7 +528,7 @@ func (b *Broker) connectRouter(id, addr string) {
 
 			log.Debug("Connect to route timeout, retry...")
 
-			if 0 == timeDelay {
+			if timeDelay == 0 {
 				timeDelay = 1 * time.Second
 			} else {
 				timeDelay *= 2
@@ -714,11 +714,11 @@ func (b *Broker) BroadcastUnSubscribe(topicsToUnSubscribeFrom []string) {
 }
 
 type OnlineOfflineMsg struct {
-	ClientID	string		`json:"clientID"`
-	Online		bool		`json:"online"`
-	Timestamp	string		`json:"timestamp"`
-	ClientInfo	Info		`json:"info"`
-	LastMsgTime	int64		`json:"lastMsg"`
+	ClientID    string `json:"clientID"`
+	Online      bool   `json:"online"`
+	Timestamp   string `json:"timestamp"`
+	ClientInfo  Info   `json:"info"`
+	LastMsgTime int64  `json:"lastMsg"`
 }
 
 func (b *Broker) OnlineOfflineNotification(info Info, online bool, lastMsg int64) {
@@ -727,10 +727,10 @@ func (b *Broker) OnlineOfflineNotification(info Info, online bool, lastMsg int64
 	packet.Qos = 0
 
 	msg := OnlineOfflineMsg{
-		ClientID: info.ClientID,
-		Online: online,
-		Timestamp: time.Now().UTC().Format(time.RFC3339),
-		ClientInfo: info,
+		ClientID:    info.ClientID,
+		Online:      online,
+		Timestamp:   time.Now().UTC().Format(time.RFC3339),
+		ClientInfo:  info,
 		LastMsgTime: lastMsg,
 	}
 
diff --git a/broker/client.go b/broker/client.go
index 223efc9..c04e4fb 100644
--- a/broker/client.go
+++ b/broker/client.go
@@ -79,7 +79,7 @@ type client struct {
 	mqueue         *queue.Queue
 	retryTimer     *time.Timer
 	retryTimerLock sync.Mutex
-	lastMsgTime	int64
+	lastMsgTime    int64
 }
 
 type InflightStatus uint8
@@ -113,16 +113,16 @@ type info struct {
 }
 
 type PubPacket struct {
-	TopicName	string			`json:"topicName"`
-	Payload		[]byte			`json:"payload"`
+	TopicName string `json:"topicName"`
+	Payload   []byte `json:"payload"`
 }
 
 type Info struct {
-	ClientID  string			`json:"clientId"`
-	Username  string			`json:"username"`
-	Password  []byte			`json:"password"`
-	Keepalive uint16			`json:"keepalive"`
-	WillMsg   PubPacket			`json:"willMsg"`
+	ClientID  string    `json:"clientId"`
+	Username  string    `json:"username"`
+	Password  []byte    `json:"password"`
+	Keepalive uint16    `json:"keepalive"`
+	WillMsg   PubPacket `json:"willMsg"`
 }
 
 type route struct {
@@ -136,7 +136,7 @@ var (
 )
 
 func (c *client) init() {
-	c.lastMsgTime = time.Now().Unix()		//mark the connection packet time as last time messaged
+	c.lastMsgTime = time.Now().Unix() //mark the connection packet time as last time messaged
 	c.status = Connected
 	c.info.localIP, _, _ = net.SplitHostPort(c.conn.LocalAddr().String())
 	remoteAddr := c.conn.RemoteAddr()
@@ -867,11 +867,11 @@ func (c *client) Close() {
 		}
 
 		pubInfo := Info{
-			ClientID: c.info.clientID,
-			Username: c.info.username,
-			Password: c.info.password,
+			ClientID:  c.info.clientID,
+			Username:  c.info.username,
+			Password:  c.info.password,
 			Keepalive: c.info.keepalive,
-			WillMsg: pubPack,
+			WillMsg:   pubPack,
 		}
 		//offline notification
 		b.OnlineOfflineNotification(pubInfo, false, c.lastMsgTime)