webpack3.0升級4.0的方法步驟

阿新 • • 發佈：2020-04-04

1.webpack 3.11升級4.26

為了提升打包效率，在webpack3.11基礎之上做了升級，webpack4.0釋出以來，零配置的webpack對專案本身提供的“打包”和“壓縮”功能已經做了優化，如果在專案開始使用4.0而不用vue-cli的預設配置，遇到的問題或許能少一些。

2. 安裝/升級依賴

這些依賴有的是在build過程中發現依賴有新的替換或者報錯，逐步替換的，如果想遇到多個坑，可以先把webpack、webpack-cli升級到對應版本

devDependencies:

"extract-text-webpack-plugin": "^4.0.0-beta.0"
"html-webpack-plugin": "^4.0.0-beta.14"
"mini-css-extract-plugin": "^0.9.0" (舊的optimize-css-assets-webpack不支援了)
"preload-webpack-plugin": "^3.0.0-beta.4"
"script-ext-html-webpack-plugin": "^2.1.3"
"vue-loader": "^15.3.0"
"webpack": "^4.26.1"
"webpack-cli": "^3.1.2"
"webpack-dev-server": "^3.2.1"
"script-ext-html-webpack-plugin": "^2.1.3"

3. 遇到的問題

升級webpack後，build報錯：ERROR in ./src/App.vue
Module Error (from ./node_modules/vue-loader/lib/index.js

解決：升級vue-loader至15.3.0，

webpack.base.conf.js新增

const {VueLoaderPlugin} = require('vue-loader')
module.exports中新增
 plugins:[new VueLoaderPlugin()]

修改配置檔案 webpack.prod.conf.js：

webpack.optimize.CommonsChunkPlugin has been removed,please use config.optimization.splitChunks instead.

解決：

webpack.prod.conf.js webpackConfig配置:
optimization: {
 noEmitOnErrors: true,concatenateModules: true,splitChunks: {
  chunks: 'all',name: 'common',},runtimeChunk: {
  name: 'runtime'
 }
 }
webpack.prod.conf.js webpackConfig配置: 
optimization:{
 namedModules: true
 },

Plugin could not be registered at ‘html-webpack-plugin-before-html-processing'. Hook was not found.

解決：

npm i preload-webpack-plugin@next -D

Tapable.plugin is deprecated. Use new API on .hooks instead

問題：extract-text-webpack-plugin相容問題，功能：extract css into its own file

解決：解除安裝extract-text-webpack-plugin，安裝mini-css-extract-plugin

 new MiniCssExtractPlugin({
  filename: utils.assetsPath('css/[name].[contenthash].css'),allChunks: false,}),

build出錯：ERROR in TypeError: Cannot read property ‘hash' of undefined

解決:

  去掉這段
  //打包計時
  const SpeedMeasurePlugin = require("speed-measure-webpack-plugin");
  const smp = new SpeedMeasurePlugin();

WARNING in configuration
The ‘mode' option has not been set,webpack will fallback to ‘production' for this value. Set ‘mode' option to ‘development' or ‘production' to enable defaults for each environment.
You can also set it to ‘none' to disable any default behavior. Learn more: https://webpack.js.org/concepts/mode/

解決：webpackConfig新增 mode: ‘production'

Tapable.plugin is deprecated. Use new API on .hooks instead

解決：

npm i --save-dev extract-text-webpack-plugin@next

會下載到 [email protected]

Error: webpack.optimize.CommonsChunkPlugin has been removed,please use config.o ptimization…

解決:

去掉 webpack.optimize.CommonsChunkPlugin相關配置
webpackConfig中與plugins的同級新增

optimization: {
 splitChunks: {
   cacheGroups: {
    commons: {
     name: "commons",chunks: "initial",minChunks: 2
    }
   }
  }
 },

Unhandled rejection Error: “dependency” is not a valid chunk sort mode

new HtmlWebpackPlugin({
  filename: config.build.index,template: 'index.html',inject: true,minify: {
  removeComments: true,collapseWhitespace: true,removeAttributeQuotes: true
  },// necessary to consistently work with multiple chunks via CommonsChunkPlugin
  chunksSortMode: 'dependency'
 }),

解決：chunksSortMode改為auto或者註釋

至此:npm run build 正常
接下來調npm run dev，直接執行成功

4. 總結

開啟cache的情況下，原來打包時間22s左右，現在build最快8s左右

升級思路：