Add the random string when generating the session id

config/config.go

@@ -24,22 +24,22 @@ import (
 	"fmt"
 	"net"
 	"os"
+	"strings"
 
+	"github.com/go-playground/validator/v10"
+
+	"github.com/apache/kvrocks-controller/logger"
 	"github.com/apache/kvrocks-controller/store/engine/etcd"
 	"github.com/apache/kvrocks-controller/store/engine/zookeeper"
-	"github.com/go-playground/validator/v10"
 )
 
 type AdminConfig struct {
 	Addr string `yaml:"addr"`
 }
 
 type FailOverConfig struct {
-	GCIntervalSeconds   int     `yaml:"gc_interval_seconds"`
-	PingIntervalSeconds int     `yaml:"ping_interval_seconds"`
-	MaxPingCount        int64   `yaml:"max_ping_count"`
-	MinAliveSize        int     `yaml:"min_alive_size"`
-	MaxFailureRatio     float64 `yaml:"max_failure_ratio"`
+	PingIntervalSeconds int   `yaml:"ping_interval_seconds"`
+	MaxPingCount        int64 `yaml:"max_ping_count"`
 }
 
 type ControllerConfig struct {
@@ -59,11 +59,8 @@ type Config struct {
 
 func DefaultFailOverConfig() *FailOverConfig {
 	return &FailOverConfig{
-		GCIntervalSeconds:   3600,
 		PingIntervalSeconds: 3,
 		MaxPingCount:        5,
-		MinAliveSize:        10,
-		MaxFailureRatio:     0.6,
 	}
 }
 
@@ -84,14 +81,12 @@ func (c *Config) Validate() error {
 	if c.Controller.FailOver.MaxPingCount < 3 {
 		return errors.New("max ping count required >= 3")
 	}
-	if c.Controller.FailOver.GCIntervalSeconds < 60 {
-		return errors.New("gc interval required >= 1min")
-	}
 	if c.Controller.FailOver.PingIntervalSeconds < 1 {
 		return errors.New("ping interval required >= 1s")
 	}
-	if c.Controller.FailOver.MinAliveSize < 2 {
-		return errors.New("min alive size required >= 2")
+	hostPort := strings.Split(c.Addr, ":")
+	if hostPort[0] == "0.0.0.0" || hostPort[0] == "127.0.0.1" {
+		logger.Get().Warn("Leader forward may not work if the host is " + hostPort[0])
 	}
 	return nil
 }

config/config_test.go

@@ -29,11 +29,8 @@ func TestDefaultControllerConfigSet(t *testing.T) {
 	cfg := Default()
 	expectedControllerConfig := &ControllerConfig{
 		FailOver: &FailOverConfig{
-			GCIntervalSeconds:   3600,
 			PingIntervalSeconds: 3,
 			MaxPingCount:        5,
-			MinAliveSize:        10,
-			MaxFailureRatio:     0.6,
 		},
 	}
 

server/helper/helper.go

@@ -17,15 +17,19 @@
  * under the License.
  *
  */
+
 package helper
 
 import (
 	"errors"
+	"fmt"
 	"net/http"
-
-	"github.com/apache/kvrocks-controller/consts"
+	"strings"
 
 	"github.com/gin-gonic/gin"
+
+	"github.com/apache/kvrocks-controller/consts"
+	"github.com/apache/kvrocks-controller/util"
 )
 
 type Error struct {
@@ -77,3 +81,20 @@ func ResponseError(c *gin.Context, err error) {
 	})
 	c.Abort()
 }
+
+// generateSessionID encodes the addr to a session ID,
+// which is used to identify the session. And then can be used to
+// parse the leader listening address back.
+func GenerateSessionID(addr string) string {
+	return fmt.Sprintf("%s/%s", util.RandString(8), addr)
+}
+
+// extractAddrFromSessionID decodes the session ID to the addr.
+func ExtractAddrFromSessionID(sessionID string) string {
+	parts := strings.Split(sessionID, "/")
+	if len(parts) != 2 {
+		// for the old session ID format, we use the addr as the session ID
+		return sessionID
+	}
+	return parts[1]
+}

server/helper/helper_test.go

@@ -0,0 +1,37 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ *
+ */
+
+package helper
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/require"
+)
+
+func TestGenerateSessionID(t *testing.T) {
+	testAddr := "127.0.0.1:1234"
+	sessionID := GenerateSessionID(testAddr)
+	decodedAddr := ExtractAddrFromSessionID(sessionID)
+	require.Equal(t, testAddr, decodedAddr)
+
+	// old format
+	require.Equal(t, testAddr, ExtractAddrFromSessionID(testAddr))
+}

server/middleware/middleware.go

@@ -17,6 +17,7 @@
  * under the License.
  *
  */
+
 package middleware
 
 import (
@@ -25,14 +26,13 @@ import (
 	"strconv"
 	"time"
 
-	"github.com/apache/kvrocks-controller/server/helper"
+	"github.com/gin-gonic/gin"
+	"github.com/prometheus/client_golang/prometheus"
 
 	"github.com/apache/kvrocks-controller/consts"
 	"github.com/apache/kvrocks-controller/metrics"
+	"github.com/apache/kvrocks-controller/server/helper"
 	"github.com/apache/kvrocks-controller/store"
-
-	"github.com/gin-gonic/gin"
-	"github.com/prometheus/client_golang/prometheus"
 )
 
 func CollectMetrics(c *gin.Context) {
@@ -69,6 +69,8 @@ func RedirectIfNotLeader(c *gin.Context) {
 	if !storage.IsLeader() {
 		if !c.GetBool(consts.HeaderIsRedirect) {
 			c.Set(consts.HeaderIsRedirect, true)
+			peerAddr := helper.ExtractAddrFromSessionID(storage.Leader())
+			c.Redirect(http.StatusTemporaryRedirect, "http://"+peerAddr+c.Request.RequestURI)
 			c.Redirect(http.StatusTemporaryRedirect, "http://"+storage.Leader()+c.Request.RequestURI)
 		} else {
 			c.JSON(http.StatusBadRequest, gin.H{"error": "no leader now, please retry later"})

server/server.go

@@ -17,6 +17,7 @@
  * under the License.
  *
  */
+
 package server
 
 import (
@@ -32,6 +33,7 @@ import (
 	"github.com/apache/kvrocks-controller/config"
 	"github.com/apache/kvrocks-controller/controller"
 	"github.com/apache/kvrocks-controller/logger"
+	"github.com/apache/kvrocks-controller/server/helper"
 	"github.com/apache/kvrocks-controller/store"
 	"github.com/apache/kvrocks-controller/store/engine"
 	"github.com/apache/kvrocks-controller/store/engine/etcd"
@@ -49,16 +51,18 @@ type Server struct {
 func NewServer(cfg *config.Config) (*Server, error) {
 	var persist engine.Engine
 	var err error
+
+	sessionID := helper.GenerateSessionID(cfg.Addr)
 	switch {
 	case strings.EqualFold(cfg.StorageType, "etcd"):
 		logger.Get().Info("Use Etcd as store")
-		persist, err = etcd.New(cfg.Addr, cfg.Etcd)
+		persist, err = etcd.New(sessionID, cfg.Etcd)
 	case strings.EqualFold(cfg.StorageType, "zookeeper"):
 		logger.Get().Info("Use Zookeeper as store")
-		persist, err = zookeeper.New(cfg.Addr, cfg.Zookeeper)
+		persist, err = zookeeper.New(sessionID, cfg.Zookeeper)
 	default:
 		logger.Get().Info("Use Etcd as default store")
-		persist, err = etcd.New(cfg.Addr, cfg.Etcd)
+		persist, err = etcd.New(sessionID, cfg.Etcd)
 	}
 
 	if err != nil {