Node.js 实现微信小程序带参数二维码生成

var fs = require('fs'); 
var request = require('request'); 
var wx_conf = require('../../conf/wx_conf');//这里放了微信appid跟appSecret，文件没有引入进来，要用的时候，改一下吧。 
var AccessToken = { 
 grant_type: 'client_credential', 
 appid: wx_conf.appId, 
 secret: wx_conf.appSecret 
} 
var wx_gettoken_url = 'https://api.weixin.qq.com/cgi-bin/token?grant_type=' + AccessToken.grant_type + '&appid=' + AccessToken.appid + '&secret=' + AccessToken.secret; 
//请求二维码的参数 
var postData = { 
 path: "pages/index/index", 
 width: 430 
} 
var createQrcode = { 
 create: function() { 
  console.log('fn：create'); 
  this.getToken(); 
 }, 
 //获取微信的token 
 getToken: function() { 
  console.log('fn：getToken'); 
  var that = this; 
  new Promise((resolve, reject) => { 
   console.log('进入Promise方法了'); 
   request({ 
    method: 'GET', 
    url: wx_gettoken_url 
   }, function(err, res, body) { 
    if (res) { 
     resolve({ 
      isSuccess: true, 
      data: JSON.parse(body) 
     }); 
    } else { 
     console.log (err); 
     reject({ 
      isSuccess: false, 
      data: err 
     }); 
    } 
   }) 
  }).then(proData => { 
   that.getQrcode(proData); 
  }); 
 }, 
 //生成二维码 
 getQrcode: function(proData) { 
  console.log ('fn：getQrcode'); 
  if (proData.isSuccess) { 
   postData = JSON.stringify(postData); 
   request({ 
    method: 'POST', 
    url: 'https://api.weixin.qq.com/cgi-bin/wxaapp/createwxaqrcode?access_token=' + proData.data.access_token, 
    body: postData 
   }).pipe(fs.createWriteStream('./public/images/index.png'));//路径自己定义吧 
  } else { 
   console.log('Promise请求数据出错'); 
  } 
 } 
} 
module.exports = createQrcode;//暴露对象，调用create方法既可以创建二维码