add ob configserver (#943)

tools/ob-configserver/lib/net/net.go

@@ -0,0 +1,34 @@
+/**
+ * Copyright (c) 2021 OceanBase
+ * OceanBase CE is licensed under Mulan PubL v2.
+ * You can use this software according to the terms and conditions of the Mulan PubL v2.
+ * You may obtain a copy of Mulan PubL v2 at:
+ *          http://license.coscl.org.cn/MulanPubL-2.0
+ * THIS SOFTWARE IS PROVIDED ON AN "AS IS" BASIS, WITHOUT WARRANTIES OF ANY KIND,
+ * EITHER EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO NON-INFRINGEMENT,
+ * MERCHANTABILITY OR FIT FOR A PARTICULAR PURPOSE.
+ * See the Mulan PubL v2 for more details.
+ */
+
+package net
+
+import (
+	"net"
+
+	"github.com/pkg/errors"
+)
+
+func GetLocalIpAddress() (string, error) {
+	addrs, err := net.InterfaceAddrs()
+	if err != nil {
+		return "", errors.Errorf("failed to get local ip address, cannot get network interfaces: %s", err)
+	}
+	for _, addr := range addrs {
+		if ipnet, ok := addr.(*net.IPNet); ok && !ipnet.IP.IsLoopback() {
+			if ipnet.IP.To4() != nil {
+				return ipnet.IP.String(), nil
+			}
+		}
+	}
+	return "", errors.New("failed to get local ip address, no ip address found")
+}