koa2 小程序获取access_token 带参数二维码

安装koa2-request、fs、request、并引入

const koa2Req = require('koa2-request')
const fs = require('fs')
const request =require('request')

获取access_token

 const res = await koa2Req({
 url: 'https://api.weixin.qq.com/cgi-bin/token?grant_type=client_credential&appid=' + appid + '&secret=' + appSecret + ''
 });
 let body = JSON.parse(res.body);

获取带参数二维码

 //发送post请求
 let data={
 "path":"page/index/index",
 "width":430,
 "scene":"a=34"
 }
 let options={
 url:'https://api.weixin.qq.com/wxa/getwxacodeunlimit?access_token='+body.access_token+'',
 encoding:'base64',
 json:data
 }
 request.post(options,function(err,response,body){
 // console.log(err)
 // console.log(response)
 // console.log(body)
 let dataBuffer=new Buffer(body,'base64')
 fs.writeFileSync('sdfs.png',dataBuffer)
 })

可以将二维码以base64的方式传递给前端，也可以写入文件后将路径传递给前端