How to configure config in vue (detailed tutorial)

resolve: {
  extensions: ['.js', '.vue', '.json', '.styl'],
  alias: {
   'vue$': 'vue/dist/vue.esm.js',
   '@': resolve('src'),
   'src': path.resolve(__dirname, '../src'),
   'common': path.resolve(__dirname, '../src/common'),
   'components': path.resolve(__dirname, '../src/components')
  }
 }

import Vue from 'vue';
import App from './App';
import Router from 'vue-router';
//components前面可以加上'@/'，也可以省略不写
//如果没有别名，就要写成“import goods from '../components/goods/goods';“
import goods from 'components/goods/goods';
import seller from 'components/seller/seller';
import ratings from 'components/ratings/ratings';
import '@/common/stylus/index';