'use strict'

/*工具類 主要提供以下幾個(gè)方法
 * assetsPath 獲取靜態(tài)資源路徑
 * exports.cssLoaders 返回針對(duì)各類型的樣式文件的處理方式
 * exports.styleLoaders 返回webpack需要的css相關(guān)的loader的配置，它也使用了cssLoaders()
 * exports.createNotifierCallback node-notifier'是一個(gè)跨平臺(tái)系統(tǒng)通知的頁(yè)面。
 * 當(dāng)遇到錯(cuò)誤時(shí)，它能用系統(tǒng)原生的推送方式給你推送信息這個(gè)方法用于推送錯(cuò)誤信息
 * 跳轉(zhuǎn)至utils
 */
const utils = require('./utils')

//引入webpack模塊
const webpack = require('webpack')

/*引入配置文件 他下面有3個(gè)文件
 * dev.env.js 導(dǎo)出開發(fā)環(huán)境的名稱
 * prod.env.js 到處生產(chǎn)環(huán)境的名稱
 * index.js 到處不同環(huán)境需要的具體配置
 * 跳轉(zhuǎn)至config
 */
const config = require('../config')

//webpack-merge這個(gè)包，這個(gè)包的作用是來合并兩個(gè)配置文件對(duì)象并生成一個(gè)新的配置文件，有點(diǎn)兒類似于es6的Object.assign()方法。合并沖突時(shí)，第二個(gè)參數(shù)的屬性值會(huì)覆蓋第一個(gè)參數(shù)的屬性值。
const merge = require('webpack-merge')

//處理文件路徑的模塊
const path = require('path')

/* 配置webpack編譯入口
 * 配置webpack輸出路徑和命名規(guī)則
 * 配置模塊resolve規(guī)則
 * 配置不同類型模塊的處理規(guī)則
 * 跳轉(zhuǎn)至webpack.base.conf
 */
const baseWebpackConfig = require('./webpack.base.conf')

//一個(gè)負(fù)責(zé)拷貝資源的插件
const CopyWebpackPlugin = require('copy-webpack-plugin')

// 一個(gè)用于生成HTML文件并自動(dòng)注入依賴文件（link/script）的webpack插件
const HtmlWebpackPlugin = require('html-webpack-plugin')

//一個(gè)更友好的展示webpack錯(cuò)誤提示的插件
const FriendlyErrorsPlugin = require('friendly-errors-webpack-plugin')

//一個(gè)自動(dòng)檢索端口的包
const portfinder = require('portfinder')

//當(dāng)前環(huán)境HOST
const HOST = process.env.HOST

//當(dāng)前環(huán)境端口
const PORT = process.env.PORT && Number(process.env.PORT)

//baseWebpackConfig請(qǐng)?zhí)?/webpack.base.conf小節(jié)
const devWebpackConfig = merge(baseWebpackConfig, {
 module: {
  //此處的配置會(huì)覆蓋掉baseWebpackConfig的 sourceMap是否開啟，是否使用postcss
  //postcssloader 為CSS3自動(dòng)加上瀏覽器前綴
  rules: utils.styleLoaders({ sourceMap: config.dev.cssSourceMap, usePostCSS: true })
 },
 // cheap-module-eval-source-map在開發(fā)環(huán)境中最快
 devtool: config.dev.devtool,

 // devServer的配置大家看文檔就好了 配置太大不一一贅述了
 devServer: {
  clientLogLevel: 'warning',
  historyApiFallback: {
   rewrites: [
    { from: /.*/, to: path.posix.join(config.dev.assetsPublicPath, 'index.html') },
   ],
  },
  hot: true,
  contentBase: false, // since we use CopyWebpackPlugin.
  compress: true,
  host: HOST || config.dev.host,
  port: PORT || config.dev.port,
  open: config.dev.autoOpenBrowser,
  overlay: config.dev.errorOverlay
   ? { warnings: false, errors: true }
   : false,
  publicPath: config.dev.assetsPublicPath,
  proxy: config.dev.proxyTable,
  quiet: true, // necessary for FriendlyErrorsPlugin
  watchOptions: {
   poll: config.dev.poll,
  }
 },
 //插件
 plugins: [
  //配置開發(fā)環(huán)境
  new webpack.DefinePlugin({
   'process.env': require('../config/dev.env')
  }),
  //模塊熱替換的插件，修改模塊不需要刷新頁(yè)面
  new webpack.HotModuleReplacementPlugin(),
  //當(dāng)使用HotModuleReplacementPlugin時(shí)，這個(gè)插件會(huì)顯示模塊正確的相對(duì)路徑
  new webpack.NamedModulesPlugin(),
  //在編譯出錯(cuò)時(shí)，使用NoEmitOnErrorsPlugin來跳過輸出階段，這樣可以確保輸出資源不會(huì)包含錯(cuò)誤
  new webpack.NoEmitOnErrorsPlugin(),

  //這里將resume/index.html作為模版，生成一份新的index.html在build下。
  // https://github.com/ampedandwired/html-webpack-plugin
  new HtmlWebpackPlugin({
   filename: 'index.html',
   template: 'index.html',
   inject: true
  }),
  // 復(fù)制靜態(tài)資源
  new CopyWebpackPlugin([
   {
    from: path.resolve(__dirname, '../static'),
    to: config.dev.assetsSubDirectory,
    ignore: ['.*']
   }
  ])
 ]
})

//這里主要是做端口的檢索以及npm run dev后對(duì)錯(cuò)誤的處理
module.exports = new Promise((resolve, reject) => {
 portfinder.basePort = process.env.PORT || config.dev.port
 portfinder.getPort((err, port) => {
  if (err) {
   reject(err)
  } else {
   // publish the new Port, necessary for e2e tests
   process.env.PORT = port
   // add port to devServer config
   devWebpackConfig.devServer.port = port

   // Add FriendlyErrorsPlugin
   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)
  }
 })
})

'use strict'
const path = require('path')
//跳轉(zhuǎn)至config
const config = require('../config')

//這個(gè)plugin的作用是將打包后生成的css文件通過link的方式引入到html中，如果不適用這個(gè)插件css代碼會(huì)放到head標(biāo)簽的style中
const ExtractTextPlugin = require('extract-text-webpack-plugin')
const packageConfig = require('../package.json')

//process.env.NODE_ENV是一個(gè)環(huán)境變量，它是由webpack.dev/prod.conf.js這兩個(gè)文件聲明的;
//這里的意思是判斷當(dāng)前是否是開發(fā)環(huán)境，如果是就把config下index.js文件中build.assetsSubDirectory或
//dev.assetsSubDirectory的值賦給assetsSubDirectory
exports.assetsPath = function (_path) {
 const assetsSubDirectory = process.env.NODE_ENV === 'production'
  ? config.build.assetsSubDirectory
  : config.dev.assetsSubDirectory

 return path.posix.join(assetsSubDirectory, _path)
}

//cssLoaders的作用是導(dǎo)出一個(gè)供vue-loader的options使用的一個(gè)配置;
exports.cssLoaders = function (options) {
 options = options || {}

 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',
    options: Object.assign({}, loaderOptions, {
     sourceMap: options.sourceMap
    })
   })
  }

  // Extract CSS when that option is specified
  // (which is the case during production build)
  if (options.extract) {
   return ExtractTextPlugin.extract({
    use: loaders,
    fallback: 'vue-style-loader'
   })
  } else {
   return ['vue-style-loader'].concat(loaders)
  }
 }

 // https://vue-loader.vuejs.org/en/configurations/extract-css.html
 return {
  css: generateLoaders(),
  postcss: generateLoaders(),
  less: generateLoaders('less'),
  sass: generateLoaders('sass', { indentedSyntax: true }),
  scss: generateLoaders('sass'),
  stylus: generateLoaders('stylus'),
  styl: generateLoaders('stylus')
 }
}

//用來給webpack提供和css相關(guān)的loader的配置，它使用了cssLoaders方法;
exports.styleLoaders = function (options) {
 const output = []
 const loaders = exports.cssLoaders(options)

 for (const extension in loaders) {
  const loader = loaders[extension]
  output.push({
   test: new RegExp('\\.' + extension + '$'),
   use: loader
  })
 }

 return output
}
//當(dāng)遇到錯(cuò)誤時(shí)，給你推送信息
exports.createNotifierCallback = () => {
 const notifier = require('node-notifier')

 return (severity, errors) => {
  if (severity !== 'error') return

  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')
  })
 }
}

'use strict'
const path = require('path')
//跳轉(zhuǎn)至utils
const utils = require('./utils')
//跳轉(zhuǎn)至config
const config = require('../config')
//vue-load 處理.vue 結(jié)尾的文件
//跳轉(zhuǎn)至vue-loader.conf
const vueLoaderConfig = require('./vue-loader.conf')

//resolve這個(gè)函數(shù)返回的是當(dāng)前目錄下"../dir"這個(gè)文件夾，__dirname指的是當(dāng)前文件所在路徑
function resolve (dir) {
 return path.join(__dirname, '..', dir)
}

//創(chuàng)建eslint規(guī)則
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 = {
 //基礎(chǔ)目錄，絕對(duì)路徑，用于從配置中解析入口起點(diǎn)(entry point)和加載器(loader)
 context: path.resolve(__dirname, '../'),

 //入口 webpack 應(yīng)該使用哪個(gè)模塊 可以是數(shù)組
 entry: {
  app: './src/main.js'
 },

 //webpack 在哪里輸出它所創(chuàng)建的 bundles，以及如何命名這些文件
 output: {
  //導(dǎo)出目錄,絕對(duì)路徑
  path: config.build.assetsRoot,
  //輸出文件的名稱
  filename: '[name].js',
  //打包后瀏覽器訪問服務(wù)時(shí)的 url 路徑,可用于改資源請(qǐng)求路徑
  publicPath: process.env.NODE_ENV === 'production'
   ? config.build.assetsPublicPath
   : config.dev.assetsPublicPath
 },
 //主要設(shè)置模塊如何被解析。
 resolve: {
  //自動(dòng)解析確定的拓展名,使導(dǎo)入模塊時(shí)不帶拓展名 例如映入./build/Test 不需要.js結(jié)尾
  extensions: ['.js', '.vue', '.json'],
  //常用模塊別名
  //import vue = import resume/node_modules/vue/dist/vue.esm.js
  alias: {
   'vue$': 'vue/dist/vue.esm.js',
   '@': resolve('src'),
  }
 },
 //模塊
 module: {
  //指定模塊解析規(guī)則
  rules: [
   //ES6新加入和擴(kuò)展運(yùn)算符
   ...(config.dev.useEslint ? [createLintingRule()] : []),
   {
    test: /\.vue$/,
    loader: 'vue-loader',
    options: vueLoaderConfig
   },
   {
    test: /\.js$/,
    loader: 'babel-loader',
    include: [resolve('src'), resolve('test'), resolve('node_modules/webpack-dev-server/client')]
   },
   {
    test: /\.(png|jpe?g|gif|svg)(\?.*)?$/,
    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]')
    }
   }
  ]
 },
 //以下選項(xiàng)是Node.js全局變量或模塊，這里主要是防止webpack注入一些Node.js的東西到vue中
 node: {
  setImmediate: false,
  dgram: 'empty',
  fs: 'empty',
  net: 'empty',
  tls: 'empty',
  child_process: 'empty'
 }
}

'use strict'
//跳轉(zhuǎn)至utils
const utils = require('./utils')
//跳轉(zhuǎn)至config
const config = require('../config')
//開發(fā)環(huán)境生產(chǎn)環(huán)境標(biāo)識(shí)
const isProduction = process.env.NODE_ENV === 'production'

//不同環(huán)境為sourceMapEnabled 賦值: 這里都為true
const sourceMapEnabled = isProduction
 ? config.build.productionSourceMap
 : config.dev.cssSourceMap

//導(dǎo)出vue-loader的配置，這里我們用了utils文件中的cssLoaders();
module.exports = {
 //vue-loader 處理.vue文件 將vue文件轉(zhuǎn)換為JS模塊 其中定義了其他loader，對(duì)< style >< template >中的靜態(tài)資源當(dāng)做模塊來對(duì)待，并且使用webpack loaders進(jìn)行處理
 loaders: utils.cssLoaders({
  sourceMap: sourceMapEnabled,
  extract: isProduction
 }),
 //是否開啟cssSourceMap,Source map就是一個(gè)信息文件,主要用于開發(fā)環(huán)境的調(diào)試，里面儲(chǔ)存著位置信息。也就是說，轉(zhuǎn)換后的代碼的每一個(gè)位置，所對(duì)應(yīng)的轉(zhuǎn)換前的位置。
 cssSourceMap: sourceMapEnabled,
 //一個(gè)配合devtool的配置，當(dāng)給文件名插入新的hash導(dǎo)致清楚緩存時(shí)是否生成souce maps，默認(rèn)在開發(fā)環(huán)境下為true
 cacheBusting: config.dev.cacheBusting,

 //transformToRequire的作用是在模板編譯的過程中，編譯器可以將某些屬性，如src轉(zhuǎn)換為require調(diào)用;
 //配置這個(gè)之后就不需要在使用src時(shí)使用require
 transformToRequire: {
  video: ['src', 'poster'],
  source: 'src',
  img: 'src',
  image: 'xlink:href'
 }
}

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

const path = require('path')

module.exports = {
 dev: {

  // Paths
  assetsSubDirectory: 'static',
  assetsPublicPath: '/',
  proxyTable: {},

  // Various Dev Server settings
  host: 'localhost', // can be overwritten by process.env.HOST
  port: 8080, // can be overwritten by process.env.PORT, if port is in use, a free one will be determined
  autoOpenBrowser: false,
  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: '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/index.html'),

  // Paths
  assetsRoot: path.resolve(__dirname, '../dist'),
  assetsSubDirectory: 'static',
  assetsPublicPath: '/',

  /**
   * Source Maps
   */

  productionSourceMap: true,
  // https://webpack.js.org/configuration/devtool/#production
  devtool: '#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
 }
}

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

'use strict'
const merge = require('webpack-merge')
const prodEnv = require('./prod.env')
//使用webpack-merge來進(jìn)行合并，減少重復(fù)代碼。
module.exports = merge(prodEnv, {
 NODE_ENV: '"development"'
})

'use strict'
//跳轉(zhuǎn)至check-versions
require('./check-versions')()
//指定為生成環(huán)境
process.env.NODE_ENV = 'production'

// node 終端的 loading 圖
const ora = require('ora')
// 用于深度刪除模塊
const rm = require('rimraf')
const path = require('path')
// 命令行彩色輸出
const chalk = require('chalk')
const webpack = require('webpack')
//跳轉(zhuǎn)至config
const config = require('../config')
//跳轉(zhuǎn)至webpack.prod.conf
const webpackConfig = require('./webpack.prod.conf')

const spinner = ora('building for production...')
//loading圖顯示
spinner.start()

/*
*使用 rimraf 將舊的編譯輸出的文件夾刪除，然后重新編譯生成
*rimraf(f: 路徑, [opts], callback: 回調(diào))
*/
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, // If you are using ts-loader, setting this to true will make TypeScript errors show up during build.
   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'
  ))
 })
})

'use strict'
//用來在命令行輸出不同顏色文字的包，可以使用chalk.yellow("想添加顏色的文字....")
const chalk = require('chalk')
//版本解析插件
const semver = require('semver')
const packageConfig = require('../package.json')
//一個(gè)用來執(zhí)行unix命令的包
const shell = require('shelljs')

// child_process 開啟子進(jìn)程，并執(zhí)行 cmd 命令 然后返回結(jié)果
function exec (cmd) {
 return require('child_process').execSync(cmd).toString().trim()
}


const versionRequirements = [
 {
  name: 'node',
  //格式化版本號(hào)
  currentVersion: semver.clean(process.version),
  versionRequirement: packageConfig.engines.node
 }
]

// shell.which('命令')在系統(tǒng)環(huán)境變量搜索命令, 如果用的是 npm 就檢查 npm 版本
if (shell.which('npm')) {
 versionRequirements.push({
  name: 'npm',
  //執(zhí)行"npm --version"命令
  currentVersion: exec('npm --version'),
  versionRequirement: packageConfig.engines.npm
 })
}

module.exports = function () {
 const warnings = []

 for (let i = 0; i < versionRequirements.length; i++) {
  const mod = versionRequirements[i]
  //如果版本不符合package.json文件中指定的版本號(hào)，返回false,進(jìn)入if
  if (!semver.satisfies(mod.currentVersion, mod.versionRequirement)) {
   warnings.push(mod.name + ': ' +
    chalk.red(mod.currentVersion) + ' should be ' +
    chalk.green(mod.versionRequirement)
    //把當(dāng)前版本號(hào)用紅色字體 符合要求的版本號(hào)用綠色字體 給用戶提示具體合適的版本
   )
  }
 }

 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)
  //提示用戶更新版本
 }
}

'use strict'
const path = require('path')
//跳轉(zhuǎn)至utils
const utils = require('./utils')
const webpack = require('webpack')
//跳轉(zhuǎn)至config
const config = require('../config')
const merge = require('webpack-merge')
//跳轉(zhuǎn)至webpack.base.conf
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')
//是用來壓縮css代碼
const OptimizeCSSPlugin = require('optimize-css-assets-webpack-plugin')
//用來壓縮JS代碼
const UglifyJsPlugin = require('uglifyjs-webpack-plugin')

//跳轉(zhuǎn)至prod.env
const env = require('../config/prod.env')

//以下同webpack.dev.conf
//跳轉(zhuǎn)至webpack.dev.conf
const webpackConfig = merge(baseWebpackConfig, {
 module: {
  rules: utils.styleLoaders({
   sourceMap: config.build.productionSourceMap,
   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
    }
   },
   sourceMap: config.build.productionSourceMap,
   parallel: true
  }),
  // extract css into its own file
  new ExtractTextPlugin({
   filename: utils.assetsPath('css/[name].[contenthash].css'),
   // Setting the following option to `false` will not extract CSS from codesplit chunks.
   // Their CSS will instead be inserted dynamically with style-loader when the codesplit chunk has been loaded by webpack.
   // It's currently set to `true` because we are seeing that sourcemaps are included in the codesplit bundle as well when it's `false`,
   // increasing file size: https://github.com/vuejs-templates/webpack/issues/1110
   allChunks: true,
  }),
  // Compress extracted CSS. We are using this plugin so that possible
  // duplicated CSS from different components can be deduped.
  new OptimizeCSSPlugin({
   cssProcessorOptions: config.build.productionSourceMap
    ? { safe: true, map: { inline: false } }
    : { safe: true }
  }),
  // generate dist index.html with correct asset hash for caching.
  // you can customize output by editing /index.html
  // see https://github.com/ampedandwired/html-webpack-plugin
  new HtmlWebpackPlugin({
   filename: config.build.index,
   template: 'index.html',
   inject: true,
   minify: {
    removeComments: true,
    collapseWhitespace: true,
    removeAttributeQuotes: true
    // more options:
    // https://github.com/kangax/html-minifier#options-quick-reference
   },
   // necessary to consistently work with multiple chunks via CommonsChunkPlugin
   chunksSortMode: 'dependency'
  }),
  // keep module.id stable when vendor modules does not change
  new webpack.HashedModuleIdsPlugin(),
  // enable scope hoisting
  new webpack.optimize.ModuleConcatenationPlugin(),
  // split vendor js into its own file
  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
  }),
  // This instance extracts shared chunks from code splitted chunks and bundles them
  // in a separate chunk, similar to the vendor chunk
  // see: https://webpack.js.org/plugins/commons-chunk-plugin/#extra-async-commons-chunk
  new webpack.optimize.CommonsChunkPlugin({
   name: 'app',
   async: 'vendor-async',
   children: true,
   minChunks: 3
  }),

  // copy custom static assets
  new CopyWebpackPlugin([
   {
    from: path.resolve(__dirname, '../static'),
    to: config.build.assetsSubDirectory,
    ignore: ['.*']
   }
  ])
 ]
})

// 開啟 gzip 的配置
if (config.build.productionGzip) {
 const CompressionWebpackPlugin = require('compression-webpack-plugin')
/*
壓縮
更多配置：https://github.com/webpack-contrib/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
  })
 )
}

/*
webpack-bundle-analyzer 插件
解析出模塊構(gòu)成、以及各自的大小體積，最后顯示為一個(gè)頁(yè)面
地址： https://www.npmjs.com/package/webpack-bundle-analyzer
*/
if (config.build.bundleAnalyzerReport) {
 const BundleAnalyzerPlugin = require('webpack-bundle-analyzer').BundleAnalyzerPlugin
 webpackConfig.plugins.push(new BundleAnalyzerPlugin())
}

module.exports = webpackConfig