build signature and append to existing url

server.go

 	req.URL.RawQuery = q.Encode()
 }
 
+func buildSignatureAppend2Url(oldURL string, token string) (newURL string) {
+	u, err := url.Parse(oldURL)
+	if err != nil {
+		log.Println(err)
+		newURL = oldURL
+		return
+	}
+	signature, timestamp, nonce := buildSignature(token)
+	q := u.Query()
+	q.Add("signature", signature)
+	q.Add("timestamp", timestamp)
+	q.Add("nonce", nonce)
+	u.RawQuery = q.Encode()
+	newURL = u.String()
+	return
+}
+
 // func checkSignature1() bool {
 // 	s1 := "e39de9f2e28079c01ebb4b803dfc3442b819545c"
 // 	t1 := "1492970761"