详解vue-cli脚手架中webpack配置方法

什么是webpack

webpack是一个module bundler（模块打包工具），所谓的模块就是在平时的前端开发中，用到一些静态资源，如javascript、css、图片等文件，webpack就将这些静态资源文件称之为模块

webpack支持amd和commonjs，以及其他的一些模块系统，并且兼容多种js书写规范，可以处理模块间的以来关系，所以具有更强大的js模块化的功能，它能对静态资源进行统一的管理以及打包发布，在官网中用这张图片介绍：

它在很多地方都能替代grunt和gulp，因为它能够编译打包css，做css预处理，对js的方言进行编译，打包图片，代码压缩等等。所以在我接触了webpack之后，就不太想用gulp了

为什么使用webpack

总结如下：

• 对 commonjs 、amd 、es6的语法做了兼容；
• 对js、css、图片等资源文件都支持打包；
• 串联式模块加载器以及插件机制，让其具有更好的灵活性和扩展性，例如提供对coffeescript、es6的支持；
• 有独立的配置文件webpack.config.js；
• 可以将代码切割成不同的chunk，实现按需加载，降低了初始化时间；
• 支持 sourceurls 和 sourcemaps，易于调试；
• 具有强大的plugin接口，大多是内部插件，使用起来比较灵活；
• webpack 使用异步 io 并具有多级缓存。这使得 webpack 很快且在增量编译上更加快；
  

webpack主要是用于vue和react较多，其实它就非常像browserify，但是将应用打包为多个文件。如果单页面应用有多个页面，那么用户只从下载对应页面的代码. 当他么访问到另一个页面, 他们不需要重新下载通用的代码。

基于本人项目使用

vue webpack的配置文件的基本目录结构如下：

config
├── dev.env.js //dev环境变量配置
├── index.js // dev和prod环境的一些基本配置
└── prod.env.js // prod环境变量配置
build
├── build.js // npm run build所执行的脚本
├── check-versions.js // 检查npm和node的版本
├── logo.png
├── utils.js // 一些工具方法，主要用于生成cssloader和styleloader配置
├── vue-loader.conf.js // vueloader的配置信息
├── webpack.base.conf.js // dev和prod的公共配置
├── webpack.dev.conf.js // dev环境的配置
└── webpack.prod.conf.js // prod环境的配置

config文件夹下文件详解

dev.env.js

config内的文件其实是服务于build的，大部分是定义一个变量export出去

use strict //[采用严格模式]
/**
* [webpack-merge提供了一个合并函数，它将数组和合并对象创建一个新对象
] 
*/
const merge = require('webpack-merge')
const prodenv = require('./prod.env')

module.exports = merge(prodenv, {
 node_env: '"development"'
})

prod.env.js

当开发时调取dev.env.js的开发环境配置，发布时调用prod.env.js的生产环境配置

use strict
module.exports = {
node_env: '"production"'
}

index.js

const path = require('path')
module.exports = {
 /**
  * [开发环境配置]
  */
dev: {
  assetssubdirectory: 'static', // [子目录,一般存放css,js,image等文件]
assetspublicpath: '/', // [根目录]
/**
* [配置服务代理] 
*/
  proxytable: {
   '/hcm': {
    target: 'https://127.0.0.1:8448',
    changeorigin: true,
    secure: false
   },
   headers: {
    "access-control-allow-origin": "*",
    "access-control-allow-methods": "get, post, put, delete, patch, options",
    "access-control-allow-headers": "x-requested-with, content-type, authorization"
   }
  },
  host: '127.0.0.1', // [浏览器访问地址]
  port: 8083, // [端口号设置，端口号占用出现问题可在此处修改]
  autoopenbrowser: true, // [是否在编译（输入命令行npm run dev）后打开http://127.0.0.1:8083/页面]
  erroroverlay: true, // [浏览器错误提示]
  notifyonerrors: true, // [跨平台错误提示]
  poll:false, // [使用文件系统(file system)获取文件改动的通知devserver.watchoptions] 
  useeslint: true, // [是否启用代码规范检查]
  showeslinterrorsinoverlay: false, // [是否展示eslint的错误提示]
  devtool: 'eval-source-map', // [增加调试，该属性为原始源代码]
  cachebusting: true, // [使缓存失效]
  csssourcemap: false // [代码压缩后进行调bug定位将非常困难，于是引入sourcemap记录压缩前后的位置信息记录，当产生错误时直接定位到未压缩前的位置，将大大的方便我们调试]
 },
/**
* [生产环境配置] 
*/
 build: {
 /**
* [index、login、license、forbidden、notfound、internal.licenses编译后生成的位置和名字，根据需要改变后缀] 
*/
  index: path.resolve(__dirname, '../../hcm-modules/hcm-web/src/main/resources/meta-inf/resources/index.html'),
  login: path.resolve(__dirname, '../../hcm-modules/hcm-web/src/main/resources/meta-inf/resources/login.html'),
  license: path.resolve(__dirname, '../../hcm-modules/hcm-web/src/main/resources/meta-inf/resources/license.html'),
  forbidden: path.resolve(__dirname, '../../hcm-modules/hcm-web/src/main/resources/meta-inf/resources/error/403.html'),
  notfound: path.resolve(__dirname, '../../hcm-modules/hcm-web/src/main/resources/meta-inf/resources/error/404.html'),
  internal: path.resolve(__dirname, '../../hcm-modules/hcm-web/src/main/resources/meta-inf/resources/error/500.html'),
  licenses: path.resolve(__dirname, '../../hcm-modules/hcm-web/src/main/resources/meta-inf/resources/docs/licenses.html'),
/**
* [编译后存放生成环境代码的位置] 
*/
  assetsroot: path.resolve(__dirname, '../../hcm-modules/hcm-web/src/main/resources/meta-inf/resources'),
  assetssubdirectory: 'static', //js、css、images存放文件夹名
  assetspublicpath: './', //发布的根目录，通常本地打包dist后打开文件会报错，此处修改为./。如果是上线的文件，可根据文件存放位置进行更改路径
  productionsourcemap: true,
  devtool: '#source-map',
  productiongzip: false, //unit的gzip命令用来压缩文件，gzip模式下需要压缩的文件的扩展名有js和css
  productiongzipextensions: ['js', 'css'],
  bundleanalyzerreport: process.env.npm_config_report //打包分析
 }
}

build文件夹下文件详解

build.js

该文件作用，即构建生产版本。package.json中的scripts的build就是node build/build.js，输入命令行npm run build对该文件进行编译生成生产环境的代码。

require('./check-versions')() //check-versions：调用检查版本的文件。加（）代表直接调用该函数
process.env.node_env = 'production' //设置当前是生产环境
/**
*下面定义常量引入插件
*/
const ora = require('ora') //加载动画
const rm = require('rimraf') //删除文件
const path = require('path')
const chalk = require('chalk') //对文案输出的一个彩色设置
const webpack = require('webpack')
const config = require('../config') //默认读取下面的index.js文件
const webpackconfig = require('./webpack.prod.conf')
const spinner = ora('building for production...') //调用start的方法实现加载动画，优化用户体验
spinner.start()
//先删除dist文件再生成新文件，因为有时候会使用hash来命名，删除整个文件可避免冗余
rm(path.join(config.build.assetsroot, config.build.assetssubdirectory), err => {
 if (err) throw err
 webpack(webpackconfig, (err, stats) => {
  spinner.stop()
  if (err) throw err
  process.stdout.write(stats.tostring({
   colors: true,
   modules: false,
   children: false,
   chunks: false,
   chunkmodules: false
  }) + '\n\n')
  if (stats.haserrors()) {
   console.log(chalk.red(' build failed with errors.\n'))
   process.exit(1)
  }
  console.log(chalk.cyan(' build complete.\n'))
  console.log(chalk.yellow(
   ' tip: built files are meant to be served over an http server.\n' +
   ' opening index.html over file:// won\'t work.\n'
  ))
 })
})

check-versions.js

该文件用于检测node和npm的版本，实现版本依赖

const chalk = require('chalk') 
const semver = require('semver') //对版本进行检查
const packageconfig = require('../package.json')
const shell = require('shelljs')
function exec (cmd) {
 //返回通过child_process模块的新建子进程，执行 unix 系统命令后转成没有空格的字符串
 return require('child_process').execsync(cmd).tostring().trim()
}
const versionrequirements = [
 {
  name: 'node',
  currentversion: semver.clean(process.version), //使用semver格式化版本
  versionrequirement: packageconfig.engines.node //获取package.json中设置的node版本
 }
]
if (shell.which('npm')) {
 versionrequirements.push({
  name: 'npm',
  currentversion: exec('npm --version'), // 自动调用npm --version命令，并且把参数返回给exec函数，从而获取纯净的版本号
  versionrequirement: packageconfig.engines.npm
 })
}
module.exports = function () {
 const warnings = []
 for (let i = 0; i < versionrequirements.length; i++) {
  const mod = versionrequirements[i]
  if (!semver.satisfies(mod.currentversion, mod.versionrequirement)) {
   //上面这个判断就是如果版本号不符合package.json文件中指定的版本号，就执行下面错误提示的代码
warnings.push(mod.name + ': ' +
    chalk.red(mod.currentversion) + ' should be ' +
    chalk.green(mod.versionrequirement)
   )
  }
 }
 if (warnings.length) {
  console.log('')
  console.log(chalk.yellow('to use this template, you must update following to modules:'))
  console.log()
  for (let i = 0; i < warnings.length; i++) {
   const warning = warnings[i]
   console.log(' ' + warning)
  }
  console.log()
  process.exit(1)
 }
}

utils.js

utils是工具的意思，是一个用来处理css的文件。

const path = require('path')
const config = require('../config')
const extracttextplugin = require('extract-text-webpack-plugin')
const packageconfig = require('../package.json')
exports.assetspath = function (_path) {
 const assetssubdirectory = process.env.node_env === 'production'
  ? config.build.assetssubdirectory
  : config.dev.assetssubdirectory
 return path.posix.join(assetssubdirectory, _path)
}
exports.cssloaders = function (options) {
 options = options || {}
//使用了css-loader和postcssloader，通过options.usepostcss属性来判断是否使用postcssloader中压缩等方法

 const cssloader = {
  loader: 'css-loader',
  options: {
   sourcemap: options.sourcemap
  }
 }
 const postcssloader = {
  loader: 'postcss-loader',
  options: {
   sourcemap: options.sourcemap
  }
 }
 // generate loader string to be used with extract text plugin
 function generateloaders (loader, loaderoptions) {
  const loaders = options.usepostcss ? [cssloader, postcssloader] : [cssloader]
  if (loader) {
   loaders.push({
    loader: loader + '-loader',
  //object.assign是es6语法的浅复制，后两者合并后复制完成赋值
    options: object.assign({}, loaderoptions, {
     sourcemap: options.sourcemap
    })
   })
  }
  // extract css when that option is specified
  // (which is the case during production build)
if (options.extract) {
//extracttextplugin可提取出文本，代表首先使用上面处理的loaders，当未能正确引入时使用vue-style-loader
   return extracttextplugin.extract({
    use: loaders,
    fallback: 'vue-style-loader',
    publicpath: '../../'
   })
} else {
//返回vue-style-loader连接loaders的最终值
   return ['vue-style-loader'].concat(loaders)
  }
 }
 // https://vue-loader.vuejs.org/en/configurations/extract-css.html
 return {
  css: generateloaders(),//需要css-loader 和 vue-style-loader
  postcss: generateloaders(),//需要css-loader和postcssloader 和 vue-style-loader
  less: generateloaders('less'), //需要less-loader 和 vue-style-loader
  sass: generateloaders('sass', { indentedsyntax: true }), //需要sass-loader 和 vue-style-loader
  scss: generateloaders('sass'), //需要sass-loader 和 vue-style-loader
  stylus: generateloaders('stylus'), //需要stylus-loader 和 vue-style-loader
  styl: generateloaders('stylus') //需要stylus-loader 和 vue-style-loader
 }
}
// generate loaders for standalone style files (outside of .vue)
exports.styleloaders = function (options) {
 const output = []
 const loaders = exports.cssloaders(options)
//将各种css,less,sass等综合在一起得出结果输出output
 for (const extension in loaders) {
  const loader = loaders[extension]
  output.push({
   test: new regexp('\\.' + extension + '$'),
   use: loader
  })
 }
 return output
}
exports.createnotifiercallback = () => {
//发送跨平台通知系统
 const notifier = require('node-notifier')
 return (severity, errors) => {
if (severity !== 'error') return
//当报错时输出错误信息的标题，错误信息详情，副标题以及图标
  const error = errors[0]
  const filename = error.file && error.file.split('!').pop()
  notifier.notify({
   title: packageconfig.name,
   message: severity + ': ' + error.name,
   subtitle: filename || '',
   icon: path.join(__dirname, 'logo.png')
  })
 }
}

vue-loader.conf.js

该文件的主要作用就是处理.vue文件，解析这个文件中的每个语言块（template、script、style),转换成js可用的js模块。

const utils = require('./utils')
const config = require('../config')
const isproduction = process.env.node_env === 'production'
const sourcemapenabled = isproduction
 ? config.build.productionsourcemap
 : config.dev.csssourcemap
//处理项目中的css文件，生产环境和测试环境默认是打开sourcemap，而extract中的提取样式到单独文件只有在生产环境中才需要
module.exports = {
 loaders: utils.cssloaders({
  sourcemap: sourcemapenabled,
  extract: isproduction
 }),
 csssourcemap: sourcemapenabled,
 cachebusting: config.dev.cachebusting,
// 在模版编译过程中，编译器可以将某些属性，如 src 路径，转换为require调用，以便目标资源可以由 webpack 处理
 transformtorequire: {
  video: ['src', 'poster'],
  source: 'src',
  img: 'src',
  image: 'xlink:href'
 }
}

webpack.base.conf.js

webpack.base.conf.js是开发和生产共同使用提出来的基础配置文件，主要实现配制入口，配置输出环境，配置模块resolve和插件等

const path = require('path')
const utils = require('./utils')
/**
* [引入index.js文件路径] 
*/
const config = require('../config')
const vueloaderconfig = require('./vue-loader.conf')

/**
 * [获取文件路径]
 * @param dir [文件名称]
 *_dirname为当前模块文件所在目录的绝对路径* 
 *@return 文件绝对路径
*/
function resolve (dir) {
 return path.join(__dirname, '..', dir)
}
const createlintingrule = () => ({
 test: /\.(js|vue)$/,
 loader: 'eslint-loader',
 enforce: 'pre',
 include: [resolve('src'), resolve('test')],
 options: {
  formatter: require('eslint-friendly-formatter'),
  emitwarning: !config.dev.showeslinterrorsinoverlay
 }
})

module.exports = {
 context: path.resolve(__dirname, '../'),
  /**
    * [入口文件配置]
   */
 entry: {
/**
    * [入口文件路径, babel-polyfill是对es6语法的支持]
   */
  app: ['babel-polyfill', './src/main.js'],
  login: ['babel-polyfill', './src/loginmain.js'],
  license: ['babel-polyfill', './src/licensemain.js']
 },
/**
  * [文件导出配置]
*/
 output: {
  path: config.build.assetsroot,
  filename: '[name].js',
  publicpath: process.env.node_env === 'production'
   ? config.build.assetspublicpath
   : config.dev.assetspublicpath //公共存放路径
 },
 resolve: {
  /**
    * [extensions: 配置文件的扩展名,当在important文件时,不用需要添加扩展名]
   */
extensions: ['.js', '.vue', '.json'],
/**
    * [alias 给路径定义别名]
*/
  alias: {
   'vue$': 'vue/dist/vue.esm.js',
   '@': resolve('src')
  }
 },
/**
*使用插件配置相应文件的处理方法
*/
 module: {
rules: [
   ...(config.dev.useeslint ? [createlintingrule()] : []),
/**
   * [使用vue-loader将vue文件转化成js的模块]
*/
   {
    test: /\.vue$/,
    loader: 'vue-loader',
    options: vueloaderconfig
   },
/**
    * [通过babel-loader将js进行编译成es5/es6 文件]
*/
   {
    test: /\.js$/,
    loader: 'babel-loader',
    include: [resolve('src'), resolve('test')]
   },
/**
   * [图片、音像、字体都使用url-loader进行处理，超过10000会编译成base64]
*/
   {
    test: /\.(png|jpe?g|gif|svg)(\?.*)?$/,
    loader: 'url-loader',
    options: {
     limit: 10000,
     name: utils.assetspath('img/[name].[hash:7].[ext]')
    }
   },
   {
    test: /\.(mp4|webm|ogg|mp3|wav|flac|aac)(\?.*)?$/,
    loader: 'url-loader',
    options: {
     limit: 10000,
     name: utils.assetspath('media/[name].[hash:7].[ext]')
    }
   },
   {
    test: /\.(woff2?|eot|ttf|otf)(\?.*)?$/,
    loader: 'url-loader',
    options: {
     limit: 10000,
     name: utils.assetspath('fonts/[name].[hash:7].[ext]')
    }
   },
/**
    * [canvas 解析]
*/
   {
    test: path.resolve(`${resolve('src')}/lib/jtopo.js`),
    loader: ['exports-loader?window.jtopo', 'script-loader']
   }
  ]
 },
//以下选项是node.js全局变量或模块，这里主要是防止webpack注入一些node.js的东西到vue中 
 node: {
  setimmediate: false,
  dgram: 'empty',
  fs: 'empty',
  net: 'empty',                           
  tls: 'empty',
  child_process: 'empty'
 }
}

webpack.dev.conf.js

const path = require('path')
const utils = require('./utils')
const webpack = require('webpack')
const config = require('../config')
//通过webpack-merge实现webpack.dev.conf.js对wepack.base.config.js的继承
const merge = require('webpack-merge')
const basewebpackconfig = require('./webpack.base.conf')
const htmlwebpackplugin = require('html-webpack-plugin')
//美化webpack的错误信息和日志的插件
const friendlyerrorsplugin = require('friendly-errors-webpack-plugin')
// 查看空闲端口位置，默认情况下搜索8000这个端口
const portfinder = require('portfinder')
// processs为node的一个全局对象获取当前程序的环境变量，即host
const host = process.env.host
const port = process.env.port && number(process.env.port)
function resolveapp(relativepath) {
 return path.resolve(relativepath);
}
const devwebpackconfig = merge(basewebpackconfig, {
 module: {
//规则是工具utils中处理出来的styleloaders，生成了css，less,postcss等规则
  rules: utils.styleloaders({ sourcemap: config.dev.csssourcemap, usepostcss: true })
 },
// 增强调试
 devtool: config.dev.devtool,
// 此处的配置都是在config的index.js中设定好了
 devserver: {
//控制台显示的选项有none, error, warning 或者 info
clientloglevel: 'warning',
//使用 html5 history api
historyapifallback: true,
hot: true, //热加载
compress: true, //压缩
  host: host || config.dev.host,
port: port || config.dev.port,
open: config.dev.autoopenbrowser, //调试时自动打开浏览器
  overlay: config.dev.erroroverlay
   ? { warnings: false, errors: true }
   : false,
  publicpath: config.dev.assetspublicpath,
proxy: config.dev.proxytable,//接口代理
quiet: true, //控制台是否禁止打印警告和错误,若用friendlyerrorsplugin 此处为 true  watchoptions: {
   poll: config.dev.poll, // 文件系统检测改动
  }
 },
 plugins: [
  new webpack.defineplugin({
   'process.env': require('../config/dev.env')
  }),
new webpack.hotmodulereplacementplugin(),//模块热替换插件，修改模块时不需要刷新页面
new webpack.namedmodulesplugin(), // 显示文件的正确名字
new webpack.noemitonerrorsplugin(), //当webpack编译错误的时候，来中端打包进程，防止错误代码打包到文件中
// https://github.com/ampedandwired/html-webpack-plugin
// 该插件可自动生成一个 html5 文件或使用模板文件将编译好的代码注入进去 
new htmlwebpackplugin({
   filename: 'index.html',
   template: 'index.html',
   inject: true,
   chunks: ['app']
  }),
  new htmlwebpackplugin({
   filename: 'login.html',
   template: 'login.html',
   inject: true,
   chunks: ['login']
  }),
  new htmlwebpackplugin({
   filename: 'license.html',
   template: 'license.html',
   inject: true,
   chunks: ['license']
  }),
  new htmlwebpackplugin({
   filename: 'licenses.html',
   template: 'licenses.html',
   inject: true,
   chunks: []
  }),
  new htmlwebpackplugin({
   filename: '404.html',
   template: path.resolve(__dirname, '../errors/404.html'),
   favicon: resolveapp('favicon.ico'),
   inject: true,
   chunks: []
  }),
  new htmlwebpackplugin({
   filename: '403.html',
   template: path.resolve(__dirname, '../errors/403.html'),
   favicon: resolveapp('favicon.ico'),
   inject: true,
   chunks: []
  }),
  new htmlwebpackplugin({
   filename: '500.html',
   template: path.resolve(__dirname, '../errors/500.html'),
   favicon: resolveapp('favicon.ico'),
   inject: true,
   chunks: []
  })
 ]
})

module.exports = new promise((resolve, reject) => {
 portfinder.baseport = process.env.port || config.dev.port
//查找端口号
 portfinder.getport((err, port) => {
  if (err) {
   reject(err)
} else {
//端口被占用时就重新设置evn和devserver的端口
   process.env.port = port
   // add port to devserver config
   devwebpackconfig.devserver.port = port
//友好地输出信息
   devwebpackconfig.plugins.push(new friendlyerrorsplugin({
    compilationsuccessinfo: {
     messages: [`your application is running here: http://${devwebpackconfig.devserver.host}:${port}`],
    },
    onerrors: config.dev.notifyonerrors
    ? utils.createnotifiercallback()
    : undefined
   }))
   resolve(devwebpackconfig)
  }
 })
})

webpack.prod.conf.js

const path = require('path')
const utils = require('./utils')
const webpack = require('webpack')
const config = require('../config')
const merge = require('webpack-merge')
const basewebpackconfig = require('./webpack.base.conf')
const copywebpackplugin = require('copy-webpack-plugin')
const htmlwebpackplugin = require('html-webpack-plugin')
const extracttextplugin = require('extract-text-webpack-plugin')
const optimizecssplugin = require('optimize-css-assets-webpack-plugin')
const uglifyjsplugin = require('uglifyjs-webpack-plugin')

const env = require('../config/prod.env')
function resolveapp(relativepath) {
 return path.resolve(relativepath);
}
const webpackconfig = merge(basewebpackconfig, {
 module: {
  rules: utils.styleloaders({
   sourcemap: config.build.productionsourcemap,//开启调试的模式。默认为true
   extract: true,
   usepostcss: true
  })
 },
 devtool: config.build.productionsourcemap ? config.build.devtool : false,
 output: {
  path: config.build.assetsroot,
  filename: utils.assetspath('js/[name].[chunkhash].js'),
  chunkfilename: utils.assetspath('js/[id].[chunkhash].js')
 },
 plugins: [
  // http://vuejs.github.io/vue-loader/en/workflow/production.html
  new webpack.defineplugin({
   'process.env': env
  }),
  new uglifyjsplugin({
   uglifyoptions: {
    compress: {
     warnings: false //警告：true保留警告，false不保留
    }
   },
   sourcemap: config.build.productionsourcemap,
   parallel: true
  }),
// extract css into its own file
//抽取文本。比如打包之后的index页面有style插入，就是这个插件抽取出来的，减少请求
new extracttextplugin({
   filename: utils.assetspath('css/[name].[contenthash].css'),
   allchunks: true,
}),
//优化css的插件
  new optimizecssplugin({
   cssprocessoroptions: config.build.productionsourcemap
    ? { safe: true, map: { inline: false } }
    : { safe: true }
  }),
  //html打包
  new htmlwebpackplugin({
   filename: config.build.index,
   template: 'index.html',
   inject: true,
//压缩
   minify: {
    removecomments: true, //删除注释
    collapsewhitespace: true, //删除空格
    removeattributequotes: true //删除属性的引号
   },
   chunks: ['vendor', 'manifest', 'app'],
   // necessary to consistently work with multiple chunks via commonschunkplugin
   chunkssortmode: 'dependency'
  }),
  new htmlwebpackplugin({
   filename: config.build.login,
   template: 'login.html',
   inject: true,
   minify: {
    removecomments: true,
    collapsewhitespace: true,
    removeattributequotes: true
   },
   chunks: ['vendor', 'manifest', 'login'],
   // necessary to consistently work with multiple chunks via commonschunkplugin
   chunkssortmode: 'dependency'
  }),
  new htmlwebpackplugin({
   filename: config.build.license,
   template: 'license.html',
   inject: true,
   minify: {
    removecomments: true,
    collapsewhitespace: true,
    removeattributequotes: true
   },
   chunks: ['vendor', 'manifest', 'license'],
   // necessary to consistently work with multiple chunks via commonschunkplugin
   chunkssortmode: 'dependency'
  }),
  new htmlwebpackplugin({
   filename: config.build.notfound,
   template: path.resolve(__dirname, '../errors/404.html'),
   inject: true,
   favicon: resolveapp('favicon.ico'),
   minify: {
    removecomments: true,
    collapsewhitespace: true,
    removeattributequotes: true
   },
   chunks: [],
   // necessary to consistently work with multiple chunks via commonschunkplugin
   chunkssortmode: 'dependency'
  }),
  new htmlwebpackplugin({
   filename: config.build.forbidden,
   template: path.resolve(__dirname, '../errors/403.html'),
   inject: true,
   favicon: resolveapp('favicon.ico'),
   minify: {
    removecomments: true,
    collapsewhitespace: true,
    removeattributequotes: true
   },
   chunks: [],
   // necessary to consistently work with multiple chunks via commonschunkplugin
   chunkssortmode: 'dependency'
  }),
  new htmlwebpackplugin({
   filename: config.build.internal,
   template: path.resolve(__dirname, '../errors/500.html'),
   inject: true,
   favicon: resolveapp('favicon.ico'),
   minify: {
    removecomments: true,
    collapsewhitespace: true,
    removeattributequotes: true
   },
   chunks: [],
   // necessary to consistently work with multiple chunks via commonschunkplugin
   chunkssortmode: 'dependency'
  }),
  new htmlwebpackplugin({
   filename: config.build.licenses,
   template: 'licenses.html',
   inject: true,
   minify: {
    removecomments: true,
    collapsewhitespace: true,
    removeattributequotes: true
   },
   chunks: [],
   // necessary to consistently work with multiple chunks via commonschunkplugin
   chunkssortmode: 'dependency'
  }),
  // keep module.id stable when vender modules does not change
  new webpack.hashedmoduleidsplugin(),
  // enable scope hoisting
new webpack.optimize.moduleconcatenationplugin(),
//抽取公共的模块, 提升你的代码在浏览器中的执行速度。
  new webpack.optimize.commonschunkplugin({
   name: 'vendor',
   minchunks (module) {
    // any required modules inside node_modules are extracted to vendor
    return (
     module.resource &&
     /\.js$/.test(module.resource) &&
     module.resource.indexof(
      path.join(__dirname, '../node_modules')
     ) === 0
    )
   }
  }),
  // extract webpack runtime and module manifest to its own file in order to
  // prevent vendor hash from being updated whenever app bundle is updated
  new webpack.optimize.commonschunkplugin({
   name: 'manifest',
   minchunks: infinity
}),
// 预编译所有模块到一个闭包中， 
 new webpack.optimize.commonschunkplugin({
   name: 'app',
   async: 'vendor-async',
   children: true,
   minchunks: 3
  }),
//复制，比如打包完之后需要把打包的文件复制到dist里面
  new copywebpackplugin([
   {
    from: path.resolve(__dirname, '../static'),
    to: config.build.assetssubdirectory,
    ignore: ['.*']
   }
  ])
 ]
})

if (config.build.productiongzip) {
 const compressionwebpackplugin = require('compression-webpack-plugin')

 webpackconfig.plugins.push(
  new compressionwebpackplugin({
   asset: '[path].gz[query]',
   algorithm: 'gzip',
   test: new regexp(
    '\\.(' +
    config.build.productiongzipextensions.join('|') +
    ')$'
   ),
   threshold: 10240,
   minratio: 0.8
  })
 )
}
// 提供带 content-encoding 编码的压缩版的资源
if (config.build.bundleanalyzerreport) {
 const bundleanalyzerplugin = require('webpack-bundle-analyzer').bundleanalyzerplugin
 webpackconfig.plugins.push(new bundleanalyzerplugin())
}
module.exports = webpackconfig

以上就是本文的全部内容，希望对大家的学习有所帮助，也希望大家多多支持。