怎么在 vue-cli下面實(shí)現(xiàn)跨域請(qǐng)求&&webpack 的 dev-server 里面的after和before方法怎么使用？

1、看了webpack 的配置說明，但是不知道怎么使用
2、這是我在index里面做的嘗試，

'use strict'
// Template version: 1.2.3
// see http://vuejs-templates.github.io/webpack for documentation.

const path = require('path')
var express = require('express')
var app = express()
var axios = require('axios')
var apiRoutes = express.Router()

    module.exports = {
      dev: {
        // Paths
        assetsSubDirectory: 'static',
        assetsPublicPath: '/',
        proxyTable: { //跨域。。。代理服務(wù) 
          '/api': {
                    target: 'https://c.y.qq.com/lyric/fcgi-bin/fcg_query_lyric_new.fcg',
                changeOrigin: true,
                pathRewrite: {
                 '^/api': ''
                }
          }
        },
        // Various Dev Server settings
        host: 'localhost', // can be overwritten by process.env.HOST
        port: 8085, // can be overwritten by process.env.HOST, if port is in use, a free one will be determined
        autoOpenBrowser: true,
        errorOverlay: true,
        notifyOnErrors: true,
        poll: false, // https://webpack.js.org/configuration/dev-server/#devserver-watchoptions-
    
        // Use Eslint Loader?
        // If true, your code will be linted during bundling and
        // linting errors and warnings will be shown in the console.
        useEslint: true,
        // If true, eslint errors and warnings will also be shown in the error overlay
        // in the browser.
        showEslintErrorsInOverlay: false,
    
        /**
         * Source Maps
         */
    
        // https://webpack.js.org/configuration/devtool/#development
        devtool: 'eval-source-map',
    
        // If you have problems debugging vue-files in devtools,
        // set this to false - it *may* help
        // https://vue-loader.vuejs.org/en/options.html#cachebusting
        cacheBusting: true,
    
        // CSS Sourcemaps off by default because relative paths are "buggy"
        // with this option, according to the CSS-Loader README
        // (https://github.com/webpack/css-loader#sourcemaps)
        // In our experience, they generally work as expected,
        // just be aware of this issue when enabling this option.
        cssSourceMap: false,
        before(apiRoutes) {
          apiRoutes.get('/lyric', function (req, res) {
              var url = 'https://c.y.qq.com/lyric/fcgi-bin/fcg_query_lyric_new.fcg'
              axios.get(url, {
                headers: {
                  referer: 'https://c.y.qq.com/',
                  host: 'c.y.qq.com'
                },
                params: req.query
              }).then((response) => {
                var ret = response.data
                if (typeof ret === 'string') {
                    /* \w:字母、數(shù)字、下劃線   中間就是以大括號(hào)開始，小括號(hào)結(jié)束且不為（ 、）的字符，一個(gè)和多個(gè)*/
                  var reg = /^\w+\(({[^()]+})\)$/ /*==> MusicJsonCallback({\"retcode\":0,\"code\":0,\"subcode\...."})*/
                  var matches = ret.match(reg)
                  if (matches) {
                    ret = JSON.parse(matches[1])
                  }
                }
                res.json(ret)
              }).catch((e) => {
                console.log(e)
              })
            })
        },
        after(apiRoutes){
          apiRoutes.get('/lyric', function (req, res) {
              var url = 'https://c.y.qq.com/lyric/fcgi-bin/fcg_query_lyric_new.fcg'
              axios.get(url, {
                headers: {
                  referer: 'https://c.y.qq.com/',
                  host: 'c.y.qq.com'
                },
                params: req.query
              }).then((response) => {
                var ret = response.data
                if (typeof ret === 'string') {
                    /* \w:字母、數(shù)字、下劃線   中間就是以大括號(hào)開始，小括號(hào)結(jié)束且不為（ 、）的字符，一個(gè)和多個(gè)*/
                  var reg = /^\w+\(({[^()]+})\)$/ /*==> MusicJsonCallback({\"retcode\":0,\"code\":0,\"subcode\...."})*/
                  var matches = ret.match(reg)
                  if (matches) {
                    ret = JSON.parse(matches[1])
                  }
                }
                res.json(ret)
                console.log(res.json(ret))
              }).catch((e) => {
                console.log(e)
              })
            })
        }
      },

3、

    export function getLyric(mid) {
    
      const url = '/api/lyric'
    
      const data = Object.assign({}, commonParams, {
          g_tk: 5381,
        songmid: mid,
        platform: 'yqq',
        hostUin: 0,
        needNewCode: 0,
        categoryId: 10000000,
        pcachetime: +new Date(),
        format: 'json'
      })
    
      return axios.get(url, {
        params: data
      }).then((res) => {
        return Promise.resolve(res.data)
      })
    }

4、找不到目標(biāo)地址

5、 下面的after和before方法，不知道怎么用,起作用的就只是proxy,Please help me! Thanks very much!