手撕vue-cli配置——webpack.prod.conf.js篇

'use strict'
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')
//資源拷貝的插件
const CopyWebpackPlugin = require('copy-webpack-plugin')
const HtmlWebpackPlugin = require('html-webpack-plugin')
//把css打包成css文件已link的方式引入的包
const ExtractTextPlugin = require('extract-text-webpack-plugin')
//壓縮css的包
const OptimizeCSSPlugin = require('optimize-css-assets-webpack-plugin')
//壓縮js代碼的包
const UglifyJsPlugin = require('uglifyjs-webpack-plugin')

const env = require('../config/prod.env')

const webpackConfig = merge(baseWebpackConfig, {
  module: {
    //loader配置，可在介紹utils的文章中查看
    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用於命名那些異步加載的模塊，比如通過require.ensure()
    chunkFilename: utils.assetsPath('js/[id].[chunkhash].js')
  },
  plugins: [
    // http://vuejs.github.io/vue-loader/en/workflow/production.html
    //設置全局變量
    new webpack.DefinePlugin({
      'process.env': env
    }),
    //壓縮js代碼
    new UglifyJsPlugin({
      uglifyOptions: {
        compress: {
          warnings: false
        }
      },
      sourceMap: config.build.productionSourceMap,
      parallel: true
    }),
    // 從所有額外的 chunk(additional chunk) 提取（默認情況下，它僅從初Zchunk(initial chunk) 中提取）當使用 CommonsChunkPlugin 並且在公共 chunk 中有提取的 chunk（來自ExtractTextPlugin.extract）時，allChunks **必須設置為 true
    new ExtractTextPlugin({
      filename: utils.assetsPath('css/[name].[contenthash].css'),
      allChunks: true,
    }),
    // 壓縮css
    new OptimizeCSSPlugin({
      cssProcessorOptions: config.build.productionSourceMap
        ? { safe: true, map: { inline: false } }
        : { safe: true }
    }),
    // 在dist目錄生成html文件
    new HtmlWebpackPlugin({
      filename: config.build.index,
      template: 'index.html',
      inject: true,
      minify: {
        removeComments: true,
        collapseWhitespace: true,
        removeAttributeQuotes: true
      },
      chunksSortMode: 'dependency'
    }),
    // 該插件會根據模塊的相對路徑生成一個四位數的hash作為模塊id, 建議用於生產環境
    new webpack.HashedModuleIdsPlugin(),
    // 去 webpack 打包時的一個取舍是將 bundle 中各個模塊單獨打包成閉包。這些打包函數使你的 JavaScript 在瀏覽器中處理的更慢。相比之下，一些工具像 Closure Compiler 和 RollupJS 可以提升(hoist)或者預編譯所有模塊到一個閉包中，提升你的代碼在瀏覽器中的執行速度。
    new webpack.optimize.ModuleConcatenationPlugin(),
    // 將第三方的包分離出來
    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
        )
      }
    }),
    // 為了避免每次更改項目代碼時導致venderchunk的chunkHash改變，我們還會單獨生成一個manifestchunk
    new webpack.optimize.CommonsChunkPlugin({
      name: 'manifest',
      minChunks: Infinity
    }),
   //我們主要邏輯的js文件
    new webpack.optimize.CommonsChunkPlugin({
      name: 'app',
      async: 'vendor-async',
      children: true,
      minChunks: 3
    }),

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

module.exports = webpackConfig