vue项目中如何实现一个微信登录功能

const qs = require('qs')
//应用授权作用域，snsapi_base （不弹出授权页面，直接跳转，只能获取用户openid），snsapi_userinfo （弹出授权页面，可通过openid拿到昵称、性别、所在地。并且，即使在未关注的情况下，只要用户授权，也能获取其信息）
const SCOPES = ['snsapi_base', 'snsapi_userinfo']

class VueWechatAuthPlugin {

 constructor () {
 this.appid = null
 this.redirect_uri = null
 this.scope = SCOPES[1]
 this._code = null
 this._redirect_uri = null
 }

 install (Vue, options) {
 let wechatAuth = this
 this.setAppId(options.appid)
 Vue.mixin({
 created: function () {
 this.$wechatAuth = wechatAuth
 },
 })

 }

 static makeState () {
 return Math.random().toString(36).substring(2, 15) +
 Math.random().toString(36).substring(2, 15)
 }

 setAppId (appid) {
 this.appid = appid
 }

 set redirect_uri (redirect_uri) {
 this._redirect_uri = encodeURIComponent(redirect_uri)
 }

 get redirect_uri () {
 return this._redirect_uri
 }

 get state () {
 return localStorage.getItem('wechat_auth:state')
 }

 set state (state) {
 localStorage.setItem('wechat_auth:state', state)
 }

 get authUrl () {
 if (this.appid === null) {
 throw 'appid must not be null'
 }
 if (this.redirect_uri === null) {
 throw 'redirect uri must not be null'
 }
 this.state = VueWechatAuthPlugin.makeState()
 return `https://open.weixin.qq.com/connect/oauth3/authorize?appid=${this.appid}&redirect_uri=${this.redirect_uri}&response_type=code&scope=${this.scope}&state=${this.state}#wechat_redirect`
 }

 returnFromWechat (redirect_uri) {
 let parsedUrl = qs.parse(redirect_uri.split('?')[1])
 if (process.env.NODE_ENV === 'development') {
 // console.log('parsedUrl: ', parsedUrl)
 this.state = null
 this._code = parsedUrl.code
 } else {
 if (this.state === null) {
 throw 'You did\'t set state'
 }
 if (parsedUrl.state === this.state) {
 this.state = null
 this._code = parsedUrl.code
 } else {
 this.state = null
 throw `Wrong state: ${parsedUrl.state}`
 }
 }
 }

 get code () {
 if (this._code === null) {
 throw 'Not get the code from wechat server!'
 }
 // console.log(this)
 // console.log('this._code: ' + this._code)
 let code = this._code
 this._code = null
 // console.log('code: ' + code)
 return code
 }
}

const vueWechatAuthPlugin = new VueWechatAuthPlugin()

if (typeof window !== 'undefined' && window.Vue) {
 window.Vue.use(VueWechatAuthPlugin)
}

export default vueWechatAuthPlugin

import wechatAuth from './plugins/wechatAuth'//微信登录插件
const qs= require('qs');
Vue.use(wechatAuth, {appid: XXXXXXXXX});

router.beforeEach((to, from, next) => {
 if (store.state.loginStatus == 0) {
 //微信未授权登录跳转到授权登录页面
 let url = window.location.href;
 //解决重复登录url添加重复的code与state问题
 let parseUrl = qs.parse(url.split('?')[1]);
 let loginUrl;
 if (parseUrl.code && parseUrl.state) {
 delete parseUrl.code;
 delete parseUrl.state;
 loginUrl = `${url.split('?')[0]}?${qs.stringify(parseUrl)}`;
 } else {
 loginUrl = url;
 }
 wechatAuth.redirect_uri = loginUrl;
 store.dispatch('setLoginStatus', 1);
 window.location.href = wechatAuth.authUrl
 } else if (store.state.loginStatus == 1) {
 try {
 wechatAuth.returnFromWechat(to.fullPath);
 } catch (err) {
 store.dispatch('setLoginStatus', 0)
 next()
 }
 store.dispatch('loginWechatAuth', wechatAuth.code).then((res) => {
 if (res.status == 1) {
 store.dispatch('setLoginStatus', 2)
 } else {
 store.dispatch('setLoginStatus', 0)
 }
 next()
 }).catch((err) => {
 next()
 })
 }else {
 next()
 }
});