use timestamp to heartbeat

Author: smallnest

CHANGELOG.md

@@ -17,6 +17,7 @@
 - Broken API: change ReadTimeout/WriteTimeout to IdleTimeout
 - Support passing Deadline of client contexts to server side
 - remove InprocessClient plugin
+- use heartbeat/tcp_keepalive to avoid client hanging
 
 
 ## 5.0 

client/client.go

@@ -6,6 +6,7 @@ import (
 	"context"
 	"crypto/tls"
 	"errors"
+	"fmt"
 	"io"
 	"net"
 	"net/url"
@@ -742,15 +743,15 @@ func (client *Client) heartbeat() {
 	if client.option.MaxWaitForHeartbeat == 0 {
 		client.option.MaxWaitForHeartbeat = 30 * time.Second
 	}
-	var request = "ping"
-	var reply string
+
 	for range t.C {
 		if client.IsShutdown() || client.IsClosing() {
 			t.Stop()
 			return
 		}
 
-		reply = ""
+		request := fmt.Sprintf("%d", time.Now().UnixNano())
+		reply := ""
 		ctx, cancel := context.WithTimeout(context.Background(), client.option.MaxWaitForHeartbeat)
 		err := client.Call(ctx, "", "", &request, &reply)
 		abnormal := false
@@ -764,6 +765,8 @@ func (client *Client) heartbeat() {
 			abnormal = true
 		}
 
+		// check request == reply
+
 		if abnormal {
 			client.Close()
 		}

server/server.go

@@ -425,8 +425,8 @@ func (s *Server) serveConn(conn net.Conn) {
 				s.Plugins.DoHeartbeatRequest(ctx, req)
 				req.SetMessageType(protocol.Response)
 				data := req.EncodeSlicePointer()
+				conn.Write(*data)
 				protocol.PutData(data)
-				conn.Write([]byte("pong"))
 				return
 			}