config 文件夹中的 index.js

//此文件是用来配置各个环境参数

'use strict'
// Template version: 1.3.1
// see http://vuejs-templates.github.io/webpack for documentation.

const path = require('path') //此文件是用来配置开发环境和生产环境的配置参数
const devEnv = require('./dev.env')
const prodEnv = require('./prod.env')
var version = ''

// 时间标识符（用于区分版本）
if (process.env.NODE_ENV === 'production' && prodEnv.VERSION_CONTROL) {
  var d = new Date();
  var yy = d.getFullYear().toString().slice(2);
  var MM = d.getMonth() + 1 >= 10 ? (d.getMonth() + 1) : '0' + (d.getMonth() + 1);
  var DD = d.getDate() >= 10 ? d.getDate() : '0' + d.getDate();
  var h = d.getHours() >= 10 ? d.getHours() : '0' + d.getHours();
  var mm = d.getMinutes() >= 10 ? d.getMinutes() : '0' + d.getMinutes();
  version = yy + MM + DD + h + mm;
}

module.exports = {
  //开发环境
  dev: {
    assetsSubDirectory: 'static', //定义静态资源根目录的子目录static
    assetsPublicPath: '/', //静态资源的公开路径
    //代理表，用来建一个虚拟api服务器来代理本机的请求，只用于开发模式
    proxyTable: devEnv.PROXY_REQUEST === false ? {} : {
      '/api': {
        target: 'http://127.0.0.1:7001', //设置调用的接口域名和端口
        changeOrigin: true, //是否允许跨域
        pathRewrite: {
          '^/api': '/' //这里理解成用‘/api’代替target里面的地址，后面组件中我们掉接口时直接用api代替 比如我要调用'http://40.00.100.100:3002/user/add'，直接写‘/api/user/add’即可
        }
      }
    },

    // Various Dev Server settings
    host: 'localhost', // can be overwritten by process.env.HOST
    port: 8081, // can be overwritten by process.env.PORT, if port is in use, a free one will be determined
    autoOpenBrowser: true, //是否在浏览器中自动打开
    errorOverlay: true, //是否查询错误
    notifyOnErrors: true, //是否通知错误
    poll: false, // https://webpack.js.org/configuration/dev-server/#devserver-watchoptions-

    // 使用Eslint加载器?
    // If true, your code will be linted during bundling and
    // linting errors and warnings will be shown in the console.
    useEslint: true,

    //如果为真，eslint错误和警告也将显示在错误叠加
    //在浏览器中。
    showEslintErrorsInOverlay: false,

    /**
     * Source Maps
     */

    // https://webpack.js.org/configuration/devtool/#development
    devtool: 'cheap-module-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,

    cssSourceMap: true
  },

  build: {
    // Template for index.html
    index: path.resolve(__dirname, `../dist/${version}/index.html`),

    // Paths
    assetsRoot: path.resolve(__dirname, `../dist/${version}`),
    assetsSubDirectory: 'static',
    assetsPublicPath: './',

    /**
     * Source Maps
     */

    productionSourceMap: true,
    // https://webpack.js.org/configuration/devtool/#production
    devtool: 'cheap-module-source-map',

    // Gzip off by default as many popular static hosts such as
    // Surge or Netlify already gzip all static assets for you.
    // Before setting to `true`, make sure to:
    // npm install --save-dev compression-webpack-plugin
    productionGzip: false,
    productionGzipExtensions: ['js', 'css'],

    // Run the build command with an extra argument to
    // View the bundle analyzer report after build finishes:
    // `npm run build --report`
    // Set to `true` or `false` to always turn it on or off
    bundleAnalyzerReport: process.env.npm_config_report
  }
}