fix nacos-instance-overwrite #2581

registry/nacos/registry.go

@@ -20,6 +20,7 @@ package nacos
 import (
 	"bytes"
 	"fmt"
+	"github.com/nacos-group/nacos-sdk-go/v2/model"
 	"math"
 	"strconv"
 	"strings"
@@ -120,6 +121,18 @@ func (nr *nacosRegistry) Register(url *common.URL) error {
 	groupName := nr.URL.GetParam(constant.NacosGroupKey, defaultGroup)
 	param := createRegisterParam(url, serviceName, groupName)
 	logger.Infof("[Nacos Registry] Registry instance with param = %+v", param)
+	selectParam := vo.SelectAllInstancesParam{
+		ServiceName: serviceName,
+		GroupName:   groupName,
+	}
+	existingInstances, err := nr.namingClient.Client().SelectAllInstances(selectParam)
+	if err != nil {
+		return perrors.Errorf("failed to fetch instances for service [%s]: %v", serviceName, err)
+	}
+	if instanceExists(existingInstances, param) {
+		logger.Infof("Instance already exists: %+v", param)
+		return nil
+	}
 	isRegistry, err := nr.namingClient.Client().RegisterInstance(param)
 	metrics.Publish(metricsRegistry.NewRegisterEvent(err == nil && isRegistry, start))
 	if err != nil {
@@ -132,6 +145,15 @@ func (nr *nacosRegistry) Register(url *common.URL) error {
 	return nil
 }
 
+// check exists
+func instanceExists(existingInstances []model.Instance, param vo.RegisterInstanceParam) bool {
+	for _, instance := range existingInstances {
+		if instance.Ip == param.Ip && instance.Port == param.Port && instance.ClusterName == param.ClusterName {
+			return true
+		}
+	}
+	return false
+}
 func createDeregisterParam(url *common.URL, serviceName string, groupName string) vo.DeregisterInstanceParam {
 	common.HandleRegisterIPAndPort(url)
 	port, _ := strconv.Atoi(url.Port)