package main
import (
    "bytes"
    "crypto/hmac"
    "crypto/sha1"
    "encoding/base64"
    "fmt"
    "sort"
    "time"
    "math/rand"
    "strconv"
    "encoding/json"
    "io/ioutil"
    "net/http"
    "net/url"
)
func random(min, max int) int {
    rand.Seed(time.Now().Unix())
    randNum := rand.Intn(max - min) + min
    return randNum
}
func postData(apiUrl string, data url.Values) string {
    res, err := http.PostForm(apiUrl, data)
    if err != nil {
        return err.Error()
    }
    defer res.Body.Close()
    result, _ := ioutil.ReadAll(res.Body)
    return string(result)
}
func main() {
    apiUrl                  := "https://api.yisu.com/sms/sendSms"
    accessId                := "*****"
    accessSecret            := "*****"
    vars, _                 := json.Marshal(map[string]string{"code":"123123","min":"5"})
    params                  := make(url.Values)
    params["accessId"]      = []string{accessId}
    params["nonce"]         = []string{strconv.Itoa(random(10000000, 99999999))}    // 隨機數
    params["timestamp"]     = []string{strconv.Itoa(int(time.Now().Unix()))}        // 時間戳
    params["phone"]         = []string{"13800000000"}   // 手機號碼
    params["templateCode"]  = []string{"100001"}        // 模板號碼
    params["templateVars"]  = []string{string(vars)}    // 模板變量
    var buf bytes.Buffer
    keys := make([]string, 0, len(params))
    for k, _ := range params {
        keys = append(keys, k)
    }
    sort.Strings(keys)
    for i := range keys {
        k := keys[i]
        buf.WriteString(k)
        buf.WriteString("=")
        buf.WriteString(params.Get(k))
        buf.WriteString("&")
    }
    buf.Truncate(buf.Len() - 1)
    hashed := hmac.New(sha1.New, []byte(accessSecret))
    hashed.Write(buf.Bytes())
    params["signature"] = []string{base64.StdEncoding.EncodeToString(hashed.Sum(nil))}  // 簽名
    result := postData(apiUrl, params)
    fmt.Println(result)
}