#微信入门代码
#!/usr/bin/env python2.7
# -*- coding: utf-8 -*-

import tornado.ioloop
import tornado.web
import hashlib
import xml.etree.ElementTree as ET
import time

def check_signature(signature, timestamp, nonce):
  # 微信公众平台里输入的token
  token="linden"
  #字典序排序
  list = [token,timestamp,nonce]
  list.sort()
  sha1=hashlib.sha1()
  map(sha1.update,list)
  hashcode=sha1.hexdigest()
  return hashcode == signature

class MainHandler(tornado.web.RequestHandler):
  def get(self):
    signature = self.get_argument('signature')
    timestamp = self.get_argument('timestamp')
    nonce = self.get_argument('nonce')
    echostr = self.get_argument('echostr')
    if check_signature(signature, timestamp, nonce):
      self.write(echostr)
    else:
      self.write('fail')
  def post(self): 
    body = self.request.body
    data = ET.fromstring(body)
    toUser = data.find('ToUserName').text
    fromUser = data.find('FromUserName').text
    createTime = int(time.time())
    msgType = data.find('MsgType').text
    content = data.find('Content').text
    msgId= data.find("MsgId").text
    # from与to在返回的时候要交换
    textTpl = """<xml>
      <ToUserName><![CDATA[%s]]></ToUserName>
      <FromUserName><![CDATA[%s]]></FromUserName>
      <CreateTime>%s</CreateTime>
      <MsgType><![CDATA[%s]]></MsgType>
      <Content><![CDATA[%s]]></Content>
      <MsgId>%s</MsgId>
      </xml>"""
    out = textTpl % (fromUser, toUser, createTime, msgType, content, msgId)
    self.write(out)

application = tornado.web.Application([
  (r"/", MainHandler),
])

if __name__ == "__main__":
  application.listen(80)
  tornado.ioloop.IOLoop.instance().start()