Nodejs Wechat

Nodejs wrapper of wechat api

Usage

Work with native http server

var http = require('http');
var xmlBodyParser = require('express-xml-parser');
var Wechat = require('nodejs-wechat');

var opt = {
  token: 'TOKEN',
  url: '/'
};
var parse = xmlBodyParser({
  type: 'text/xml'
});
var wechat = new Wechat(opt);
wechat.on('event.subscribe', function(session) {
  session.replyTextMsg('欢迎您关注我们的订阅号');
});
var server = http.createServer(function(req, res) {
  if (req.method === 'GET') {
    wechat.verifyRequest(req, res);
  } else {
    parse(req, res, function(err) {
      if (err) {
        res.end();
        return;
      }
      wechat.handleRequest(req, res);
    });
  }
});
server.listen(80);

Work with express

var express = require('express');
var app = express();
var middlewares = require('express-middlewares-js');
app.use('/weixin', middlewares.xmlBodyParser({
  type: 'text/xml'
}));

/*
  Alternative way

var xmlBodyParser = require('express-xml-parser');
app.use('/weixin', xmlBodyParser({
  type: 'text/xml',
  limit: '1mb'
}));

*/

var Wechat = require('nodejs-wechat');
var opt = {
  token: token,
  url: '/weixin'
};
var wechat = new Wechat(opt);

app.get('/weixin', wechat.verifyRequest.bind(wechat));
app.post('/weixin', wechat.handleRequest.bind(wechat));

// you can also work with other restful routes
app.use('/api', middlewares.bodyParser());

wechat.on('text', function(session) {
  session.replyTextMsg('Hello World');
});
wechat.on('image', function(session) {
  session.replyNewsMsg([{
    Title: '新鲜事',
    Description: '点击查看今天的新鲜事',
    PicUrl: 'http://..',
    Url: 'http://..'
  }]);
});
wechat.on('voice', function(session) {
  session.replyMsg({
    Title: 'This is Music',
    MsgType: 'music',
    Description: 'Listen to this music and guess ths singer',
    MusicUrl: 'http://..',
    HQMusicUrl: 'http://..',
    ThumbMediaId: '..'
  });
});

app.listen(80);

NOTE: We apply { type: 'text/xml' } to xmlBodyParser as weixin server send us a text/xml content type instead of application/xml.

API

Wechat

• #verifyRequest(req, res)

  This is a express/connect middleware, which verify the signature of request from weixin server

• #handleRequest(req, res)

  This is a express/connect middleware, which handle the request post from weixin server

• #on(msgType, handler)

  Wechat is an inheritance from event.EventEmitter. Wechat will emit an event in incoming message's MsgType, with a Session as parameter. Valid events:

  text, image, voice, video, location, link, event.subscribe, event.unsubscribe, event.SCAN, event.LOCATION, event.CLICK, event.VIEW, error

  References: 接收普通消息, 接收事件推送

Session

• incomingMessage

  This is a direct parse of weixin server request

<xml>
<ToUserName><![CDATA[toUser]]></ToUserName>
<FromUserName><![CDATA[FromUser]]></FromUserName>
<CreateTime>123456789</CreateTime>
<MsgType><![CDATA[event]]></MsgType>
<Event><![CDATA[subscribe]]></Event>
</xml>

Becomes

{
  "ToUserName": "toUser",
  "FromUserName": "FromUser",
  "CreateTime": "123456789",
  "MsgType": "event",
  "Event": "subscribe"
}

• req

  This is the request from weixin server

• res

  This is the response to weixin server

• #replyMsg(msgObject)

  Reply a message via this.res

• #replyTextMessage(content)

  Reply a text message

• #replyNewsMessage(articles)

  Reply a news messages.

TODO

• Advanced interfaces

  Will finish advanced interfaces before July/2014, welcome send pull requests :)