prevent double reply of wechat message

wechatMsg.go

 package main
 
-import "net/http"
+import (
+	"log"
+	"net/http"
+)
 
 //
 //InWechatMsg  what we received currently from wechat
 	body            interface{} //dynamic type
 	req             *http.Request
 	instantResponse chan string //instance reply channel
+	replied         bool        //whether instant response has been replied
 }
 
 func (m *InWechatMsg) init() {
+	m.replied = false
 	m.instantResponse = make(chan string)
 }
 
 }
 
 func (m *InWechatMsg) replyXML(xml string) {
-	m.instantResponse <- xml
+	if !m.replied {
+		m.replied = true
+		m.instantResponse <- xml
+	} else {
+		log.Println("BUG::doubl reply for wechat message")
+	}
 }
 
 func (m *InWechatMsg) replyText(s string) {
 	str, _ := BuildTextMsg(m.header.FromUserName, s)
-	m.instantResponse <- str
+	m.replyXML(str)
 }
 
 func (m *InWechatMsg) transfer2KF() {