一、申请公众号
获取开发者ID(AppID)和开发者密码(AppSecret)
通过AppID和AppSecret获得access_token
二、认证
1、营业执照
2、组织机构代码证 获得高级接口权限
三、绑定域名
1、微信公众平台进入“公众号设置”的“功能设置”里填写“JS接口安全域名”;
2、下载文件MP_verify_NKeyegDEdGHxmnKJ.txt放置在域名根目录下用来验证
3、在安全中心设置开发者IP白名单,否则无法获取access_token.
注:公众平台以access_token为接口调用凭据,access_token在2小时内有效,过期需要重新获取,但1天内获取次数有限,所以需要全局缓存access_token(写入文件中)
四、代码实现
const express = require('express')
const router = express.Router()
const fs = require('fs')
const { APPID, APPSECRET } = require('../config').wx
const axios = require("axios")
const { createTimestamp, createNonceStr, sign } = require('../utils/wxTools')
/**
* 获取微信config信息
* @param {*} url
*/
async function getWxParams(url) {
let wx = {
time: +new Date(),
appid: APPID,
ticket: '',
timestamp: '',
noncestr: '',
signature: ''
}
// 获取access_token
let $res = await axios.get(`https://api.weixin.qq.com/cgi-bin/token?grant_type=client_credential&appid=${APPID}&secret=${APPSECRET}`)
if ($res.status === 200) {
// 获取jsapi_ticket
$res = await axios.get(`https://api.weixin.qq.com/cgi-bin/ticket/getticket?access_token=${$res.data.access_token}&type=jsapi`)
if ($res.status == 200) {
wx.ticket = $res.data.ticket
wx.timestamp = createTimestamp()
wx.noncestr = createNonceStr()
wx.signature = sign(url, wx)
return new Promise((reject, resolve) => {
// 保存文件
fs.writeFile('./json/wxConfig.json', JSON.stringify(wx), (err) => {
if (!err) {
console.log('wxConfig文件写入成功:', new Date(wx.time))
fs.readFile('./json/wxConfig.json', 'utf-8', (error, data) => {
resolve(data)
})
} else {
console.log('wxConfig文件写入失败:', err)
reject(err)
}
})
})
}
}
}
/**
* 前端获取
*/
router.get('/getWxConfig', async (req, res) => {
let url = req.query.url
if (url) {
// 获取本地wxConfigParams文件信息
fs.readFile('./json/wxConfig.json', 'utf-8', (error, data) => {
data = JSON.parse(data)
// 判断是access_token否过期 2个小时过期
if ((+new Date() - data.time) / 1000 / 3600 >= 1.8) getWxParams(url).then(res => data = res)
res.send(data)
})
} else {
res.send({message: 'error'})
}
})
module.exports = router
config.js
module.exports = {
Mysql: {
host: '115.29.195.195',
user: 'db_daxuexi',
password: 'HKTtHZWGEjTK5ppB',
database: 'db_daxuexi'
},
wx: {
APPID: 'wx6efcd0a76539948b',
APPSECRET: 'd4ee418a23edca447dcf2f7418a90153'
}
}
utils/wxTools.js
var sha1 = require('sha1')
// 拼接字符串
function rawString(args) {
let keys = Object.keys(args);
keys = keys.sort()
let newArgs = {}
keys.forEach(function(key) {
newArgs[key.toLowerCase()] = args[key]
})
let string = '';
for (let k in newArgs) {
string += '&' + k + '=' + newArgs[k]
}
return string.substr(1)
}
module.exports = {
// 时间戳
createTimestamp() {
return parseInt(new Date().getTime() / 1000).toString()
},
// 随机字符串
createNonceStr() {
return Math.random().toString(36).substr(2, 15)
},
// 签名
sign(url, wx) {
return sha1(rawString({
jsapi_ticket: wx.ticket,
nonceStr: wx.noncestr,
timestamp: wx.timestamp,
url: url
}))
}
}
参考文档:
https://developers.weixin.qq.com/doc/offiaccount/Basic_Information/Get_access_token.html