diff --git a/alidns.go b/alidns.go
index 86551b1..9da2211 100644
--- a/alidns.go
+++ b/alidns.go
@@ -1,138 +1,143 @@
-package main
-
-import (
-	"encoding/json"
-	"flag"
-	"fmt"
-	"io/ioutil"
-	"log"
-	"net/http"
-
-	"github.com/aliyun/alibaba-cloud-sdk-go/services/alidns"
-)
-
-// TODO: support array of (Type, RR)
-type Config struct {
-	RegionId     string `json:"regionId"`
-	AccessKeyId  string `json:"accessKeyId"`
-	AccessSecret string `json:"accessSecret"`
-	DomainName   string `json:"domainName"`
-	Type         string `json:"Type"`
-	RR           string `json:"RR"`
-}
-
-type IpJson struct {
-	Status      string  `json:"status"`
-	Country     string  `json:"country"`
-	CountryCode string  `json:"countryCode"`
-	Region      string  `json:"region"`
-	RegionName  string  `json:"regionName"`
-	City        string  `json:"city"`
-	Zip         string  `json:"zip"`
-	Lat         float64 `json:"lat"`
-	Lon         float64 `json:"lon"`
-	Timezone    string  `json:"timezone"`
-	Isp         string  `json:"isp"`
-	Org         string  `json:"org"`
-	As          string  `json:"as"`
-	Query       string  `json:"query"`
-}
-
-func main() {
-
-	configPath := flag.String("config", "./config.json", "path to config file")
-	flag.Parse()
-	fmt.Println("config file path: ", *configPath)
-
-	configJson, err := ioutil.ReadFile(*configPath)
-	if err != nil {
-		log.Fatal(err.Error())
-	}
-	var config Config
-	json.Unmarshal(configJson, &config)
-
-	res, err := http.Get("http://ip-api.com/json/")
-	if err != nil {
-		log.Fatal(err)
-	}
-
-	data, err := ioutil.ReadAll(res.Body)
-	res.Body.Close()
-	if err != nil {
-		log.Fatal(err)
-	}
-	var ipJson IpJson
-	json.Unmarshal(data, &ipJson)
-	ip := ipJson.Query
-	if ipJson.Status != "success" {
-		log.Fatal("get ip failed")
-	}
-
-	client, err := alidns.NewClientWithAccessKey(config.RegionId, config.AccessKeyId, config.AccessSecret)
-
-	describeDomainRequest := alidns.CreateDescribeDomainRecordsRequest()
-	describeDomainRequest.Scheme = "https"
-
-	describeDomainRequest.DomainName = config.DomainName
-
-	domainRecords, err := client.DescribeDomainRecords(describeDomainRequest)
-	if err != nil {
-		fmt.Println(err.Error())
-	}
-
-	var i int64 = 0
-	var found bool = false
-	// find subdomain
-	for i = 0; i < domainRecords.TotalCount; i++ {
-		if config.RR == domainRecords.DomainRecords.Record[i].RR && config.Type == domainRecords.DomainRecords.Record[i].Type {
-			found = true                                           //found subdomain record
-			if ip == domainRecords.DomainRecords.Record[i].Value { // ip not changed
-				fmt.Println("ip", ip, "not changed!")
-			} else {
-				fmt.Printf("ip changed from %s to %s\n", domainRecords.DomainRecords.Record[i].Value, ip)
-				fmt.Printf("---> update %s record to %s ...\n", config.RR+"."+config.DomainName, ip)
-
-				updateDomainRecordRequest := alidns.CreateUpdateDomainRecordRequest()
-				updateDomainRecordRequest.Scheme = "https"
-				updateDomainRecordRequest.RecordId = domainRecords.DomainRecords.Record[i].RecordId
-				updateDomainRecordRequest.RR = config.RR
-				updateDomainRecordRequest.Type = config.Type
-				updateDomainRecordRequest.Value = ip
-				response, err := client.UpdateDomainRecord(updateDomainRecordRequest)
-				if err != nil {
-					fmt.Println(err.Error())
-				}
-				if response.IsSuccess() {
-					fmt.Println("success")
-				} else {
-					fmt.Printf("failed.\n%s\n", response.GetHttpContentString())
-				}
-			}
-		}
-
-	}
-
-	if !found {
-		fmt.Printf("ip is %s, but no domain record found.\n", ip)
-		fmt.Printf("---> add %s record to %s ...\n", config.RR+"."+config.DomainName, ip)
-
-		addDomainRequest := alidns.CreateAddDomainRecordRequest()
-		addDomainRequest.Scheme = "https"
-
-		addDomainRequest.DomainName = config.DomainName
-		addDomainRequest.RR = config.RR
-		addDomainRequest.Type = config.Type
-		addDomainRequest.Value = ip
-
-		response, err := client.AddDomainRecord(addDomainRequest)
-		if err != nil {
-			fmt.Println(err.Error())
-		}
-		if response.IsSuccess() {
-			fmt.Println("success")
-		} else {
-			fmt.Printf("failed.\n%s\n", response.GetHttpContentString())
-		}
-	}
-	fmt.Println()
-}
+package main
+
+import (
+	"encoding/json"
+	"flag"
+	"fmt"
+	"io/ioutil"
+	"log"
+	"net/http"
+
+	"github.com/aliyun/alibaba-cloud-sdk-go/services/alidns"
+)
+
+// TODO: support array of (Type, RR)
+
+type Record struct {
+	Type string `json:"Type"`
+	RR   string `json:"RR"`
+}
+
+type Config struct {
+	RegionId     string `json:"regionId"`
+	AccessKeyId  string `json:"accessKeyId"`
+	AccessSecret string `json:"accessSecret"`
+	DomainName   string `json:"domainName"`
+	Records      []Record
+}
+
+type IpJson struct {
+	Status      string  `json:"status"`
+	Country     string  `json:"country"`
+	CountryCode string  `json:"countryCode"`
+	Region      string  `json:"region"`
+	RegionName  string  `json:"regionName"`
+	City        string  `json:"city"`
+	Zip         string  `json:"zip"`
+	Lat         float64 `json:"lat"`
+	Lon         float64 `json:"lon"`
+	Timezone    string  `json:"timezone"`
+	Isp         string  `json:"isp"`
+	Org         string  `json:"org"`
+	As          string  `json:"as"`
+	Query       string  `json:"query"`
+}
+
+func main() {
+
+	configPath := flag.String("config", "./config.json", "path to config file")
+	flag.Parse()
+	fmt.Println("config file path: ", *configPath)
+
+	configJson, err := ioutil.ReadFile(*configPath)
+	if err != nil {
+		log.Fatal(err.Error())
+	}
+	var config Config
+	json.Unmarshal(configJson, &config)
+
+	res, err := http.Get("http://ip-api.com/json/")
+	if err != nil {
+		log.Fatal(err)
+	}
+
+	data, err := ioutil.ReadAll(res.Body)
+	res.Body.Close()
+	if err != nil {
+		log.Fatal(err)
+	}
+	var ipJson IpJson
+	json.Unmarshal(data, &ipJson)
+	ip := ipJson.Query
+	if ipJson.Status != "success" {
+		log.Fatal("get ip failed")
+	}
+
+	client, err := alidns.NewClientWithAccessKey(config.RegionId, config.AccessKeyId, config.AccessSecret)
+
+	describeDomainRequest := alidns.CreateDescribeDomainRecordsRequest()
+	describeDomainRequest.Scheme = "https"
+
+	describeDomainRequest.DomainName = config.DomainName
+
+	domainRecords, err := client.DescribeDomainRecords(describeDomainRequest)
+	if err != nil {
+		fmt.Println(err.Error())
+	}
+
+	var i int64 = 0
+	var found bool = false
+	// find subdomain
+	for i = 0; i < domainRecords.TotalCount; i++ {
+		if config.RR == domainRecords.DomainRecords.Record[i].RR && config.Type == domainRecords.DomainRecords.Record[i].Type {
+			found = true                                           //found subdomain record
+			if ip == domainRecords.DomainRecords.Record[i].Value { // ip not changed
+				fmt.Println("ip", ip, "not changed!")
+			} else {
+				fmt.Printf("ip changed from %s to %s\n", domainRecords.DomainRecords.Record[i].Value, ip)
+				fmt.Printf("---> update %s record to %s ...\n", config.RR+"."+config.DomainName, ip)
+
+				updateDomainRecordRequest := alidns.CreateUpdateDomainRecordRequest()
+				updateDomainRecordRequest.Scheme = "https"
+				updateDomainRecordRequest.RecordId = domainRecords.DomainRecords.Record[i].RecordId
+				updateDomainRecordRequest.RR = config.RR
+				updateDomainRecordRequest.Type = config.Type
+				updateDomainRecordRequest.Value = ip
+				response, err := client.UpdateDomainRecord(updateDomainRecordRequest)
+				if err != nil {
+					fmt.Println(err.Error())
+				}
+				if response.IsSuccess() {
+					fmt.Println("success")
+				} else {
+					fmt.Printf("failed.\n%s\n", response.GetHttpContentString())
+				}
+			}
+		}
+
+	}
+
+	if !found {
+		fmt.Printf("ip is %s, but no domain record found.\n", ip)
+		fmt.Printf("---> add %s record to %s ...\n", config.RR+"."+config.DomainName, ip)
+
+		addDomainRequest := alidns.CreateAddDomainRecordRequest()
+		addDomainRequest.Scheme = "https"
+
+		addDomainRequest.DomainName = config.DomainName
+		addDomainRequest.RR = config.RR
+		addDomainRequest.Type = config.Type
+		addDomainRequest.Value = ip
+
+		response, err := client.AddDomainRecord(addDomainRequest)
+		if err != nil {
+			fmt.Println(err.Error())
+		}
+		if response.IsSuccess() {
+			fmt.Println("success")
+		} else {
+			fmt.Printf("failed.\n%s\n", response.GetHttpContentString())
+		}
+	}
+	fmt.Println()
+}