add conn.go:(gettyWSConn)writePing

conn.go

@@ -183,6 +183,10 @@ func (this *gettyWSConn) write(p []byte) error {
 	return this.conn.WriteMessage(websocket.BinaryMessage, p)
 }
 
+func (this *gettyWSConn) writePing() error {
+	return this.conn.WriteMessage(websocket.PingMessage, []byte{})
+}
+
 // close websocket connection
 func (this *gettyWSConn) close(waitSec int) {
 	this.conn.UnderlyingConn().(*net.TCPConn).SetLinger(waitSec)

dev.list

@@ -11,10 +11,17 @@
 ## develop history ##
 ---
 
+- 2016/10/13
+    > 1 add conn.go:(gettyWSConn)writePing
+    >
+    > 2 modify session.go:(Session)handleLoop:Websocket session will send ping frame automatically every peroid.
+    >
+    > 3 version: 0.4.03
+
 - 2016/10/11
     > 1 fix bug: use websocket.BinaryMessage in conn.go:(gettyWSConn)write
     >
-	> 2 version: 0.4.02
+    > 2 version: 0.4.02
 
 - 2016/10/10
     > 1 delete session.go:Session{errFlag} to invoke codec.go:EventListener{OnClose&OnError} both when got a error
@@ -25,7 +32,7 @@
     >
     > 4 add modify session.go:(Session)maxMsgLen for websocket session
     >
-	> 5 version: 0.4.01
+    > 5 version: 0.4.01
 
 - 2016/10/09
     > 1 add client.go:NewWSSClient

server.go

@@ -141,7 +141,7 @@ func newWSHandler(server *Server, newSession NewSessionCallback) *wsHandler {
 		upgrader: websocket.Upgrader{
 			// in default, ReadBufferSize & WriteBufferSize is 4k
 			// HandshakeTimeout: server.HTTPTimeout,
-			CheckOrigin: func(_ *http.Request) bool { return true },
+			CheckOrigin: func(_ *http.Request) bool { return true }, // allow connections from any origin
 		},
 	}
 }

session.go

@@ -204,7 +204,7 @@ func (this *Session) SetWriter(writer Writer) {
 	this.writer = writer
 }
 
-// period is in millisecond
+// period is in millisecond. Websocket session will send ping frame automatically every peroid.
 func (this *Session) SetCronPeriod(period int) {
 	if period < 1 {
 		panic("@period < 1")
@@ -400,8 +400,10 @@ func (this *Session) RunEventLoop() {
 
 func (this *Session) handleLoop() {
 	var (
-		err  error
-		flag bool
+		err    error
+		flag   bool
+		wsFlag bool
+		wsConn *gettyWSConn
 		// start  time.Time
 		counter gxtime.CountWatch
 		// ticker  *time.Ticker // use wheel instead, 2016/09/26
@@ -428,6 +430,7 @@ func (this *Session) handleLoop() {
 		this.gc()
 	}()
 
+	wsConn, wsFlag = this.iConn.(*gettyWSConn)
 	flag = true // do not do any read/write/cron operation while got write error
 	// ticker = time.NewTicker(this.period) // use wheel instead, 2016/09/26
 LOOP:
@@ -474,6 +477,12 @@ LOOP:
 		// case <-ticker.C: // use wheel instead, 2016/09/26
 		case <-wheel.After(this.period):
 			if flag {
+				if wsFlag {
+					err = wsConn.writePing()
+					if err != nil {
+						log.Warn("wsConn.writePing() = error{%#v}", err)
+					}
+				}
 				this.listener.OnCron(this)
 			}
 		}

version.go

@@ -10,9 +10,9 @@
 package getty
 
 const (
-	Version     = "0.4.02"
-	DATE        = "2016/10/12"
+	Version     = "0.4.03"
+	DATE        = "2016/10/13"
 	GETTY_MAJOR = 0
 	GETTY_MINOR = 4
-	GETTY_BUILD = 2
+	GETTY_BUILD = 3
 )