分析vue-cli 啟動流程步驟
阿新 • • 發佈:2018-12-11
啟動流程分析
啟動入口: 找到package.json 包含工程依賴啟動命名直接查詢到 "scripts" 下的dev 啟動命令,可以看到命令啟動了webpack-dev-server 內建的服務,並且執行build/webpack.dev.conf.js 檔案
--progress 命令表示:檢視構建過程
--config 表示 自定義配置檔案
--inline 自動重新整理瀏覽器
步驟一:
webpack.dev.conf.js 指開發環境部署配置 配置原始碼分析
'use strict' //工具方法,主要分辨css預解析器包括:less,sass等,以及合併css到一個主的css檔案中 const utils = require('./utils') const webpack = require('webpack') //關於webpack 配置檔案的輸出與開發環境,如埠,靜態資源存放路徑等。詳細檢視config/index.js 配置說明 const config = require('../config') //webpack 工具 大致用於合併兩個物件配置 const merge = require('webpack-merge') const path = require('path') //關鍵檔案 webpack 編譯前端工程的配置,如入口檔案地址,輸出檔案地址,別名,檔案預解析器 const baseWebpackConfig = require('./webpack.base.conf') //webpack 拷貝外掛 配置某個起始目錄檔案拷貝到目標檔案中 const CopyWebpackPlugin = require('copy-webpack-plugin') //webpack 模板配置 配置模板檔案預模板輸出後的名稱 用來資源自動插入 const HtmlWebpackPlugin = require('html-webpack-plugin') const FriendlyErrorsPlugin = require('friendly-errors-webpack-plugin') const portfinder = require('portfinder') const HOST = process.env.HOST const PORT = process.env.PORT && Number(process.env.PORT) //使用merge 合併資源配置 詳細配置檢視步驟二 const devWebpackConfig = merge(baseWebpackConfig, { module: { rules: utils.styleLoaders({ sourceMap: config.dev.cssSourceMap, usePostCSS: true }) }, // cheap-module-eval-source-map is faster for development devtool: config.dev.devtool, // these devServer options should be customized in /config/index.js devServer: { clientLogLevel: 'warning', historyApiFallback: { rewrites: [ { from: /.*/, to: path.posix.join(config.dev.assetsPublicPath, 'index.html') }, ], }, hot: true,//是否開啟熱更新 contentBase: false, // since we use CopyWebpackPlugin. compress: true, host: HOST || config.dev.host,//IP 地址 port: PORT || config.dev.port,//埠 open: config.dev.autoOpenBrowser,//是否自動開啟瀏覽器 overlay: config.dev.errorOverlay ? { warnings: false, errors: true } : false, publicPath: config.dev.assetsPublicPath,//公用資源路徑 proxy: config.dev.proxyTable, quiet: true, // necessary for FriendlyErrorsPlugin watchOptions: { poll: config.dev.poll, } }, plugins: [ new webpack.DefinePlugin({ 'process.env': require('../config/dev.env') //使用預設靜態自定義屬性 }), new webpack.HotModuleReplacementPlugin(), //熱更新外掛 new webpack.NamedModulesPlugin(), // HMR shows correct file names in console on update. new webpack.NoEmitOnErrorsPlugin(), // https://github.com/ampedandwired/html-webpack-plugin //模板外掛,自動引入資源到模板中 new HtmlWebpackPlugin({ filename: 'index.html',//設定生成模板的名稱 template: './template/index.html',//模板的路徑 inject: true //是否自動注入 }), // copy custom static assets //拷貝檔案外掛,獲取本地下的static 拷貝到目標檔案to中 new CopyWebpackPlugin([ { from: path.resolve(__dirname, '../static'),//拷貝源 to: config.dev.assetsSubDirectory,//拷貝目的地 ignore: ['.*'] //忽略無需拷貝的檔案 } ]) ] }) 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) } }) })
config/index.js 配置原始碼分析
'use strict' // Template version: 1.3.1 // see http://vuejs-templates.github.io/webpack for documentation. //node 自帶路徑解析工具 const path = require('path') module.exports = { dev: { // Paths assetsSubDirectory: 'static',//靜態資源目錄 assetsPublicPath: '/',//其他檔案工程目錄 proxyTable: {},//設定代理 /** * 代理案例 * proxyTable: { '/api': { target: 'http://jsonplaceholder.typicode.com', changeOrigin: true, pathRewrite: { '^/api': '' } } } */ // Various Dev Server settings host: '0.0.0.0', // 主機IP地址 port: 8080, // 埠 autoOpenBrowser: false,//是否啟動自動開啟瀏覽器 errorOverlay: true, notifyOnErrors: true, poll: false, // https://webpack.js.org/configuration/dev-server/#devserver-watchoptions- /** * Source Maps */ // https://webpack.js.org/configuration/devtool/#development devtool: 'cheap-module-eval-source-map',//編譯原始碼map 目的是為了更快的排錯 // 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 // 構建打包的的檔案路徑 index: path.resolve(__dirname, '../dist/index.html'), // Paths /** * 這應該指向包含應用程式的所有靜態資產的根目錄。例如,public/對於Rails / Laravel。 */ assetsRoot: path.resolve(__dirname, '../dist'), /** * 將webpack生成的資源嵌入此目錄中 */ assetsSubDirectory: 'static', /** * 這應該是build.assetsRoot通過HTTP提供服務的URL路徑。在大多數情況下,這將是root(/)。只有在後端框架為具有路徑字首的靜態資產提供服務時才更改此項 */ 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 } }
webpack.base.conf.js 配置原始碼分析
'use strict' const path = require('path') const utils = require('./utils') const config = require('../config') const vueLoaderConfig = require('./vue-loader.conf') function resolve (dir) { return path.join(__dirname, '..', dir) } module.exports = { context: path.resolve(__dirname, '../'), entry: { app: './src/main.js' //入口檔案 }, output: { path: config.build.assetsRoot,//輸出路徑 filename: '[name].js',//檔名 publicPath: process.env.NODE_ENV === 'production' ? config.build.assetsPublicPath //開發環境輸出地址 : config.dev.assetsPublicPath //正式環境輸出地址 }, resolve: { extensions: ['.js', '.vue', '.json'], //擴充套件檔名結尾 //設定的別名 alias: { 'vue$': 'vue/dist/vue.esm.js', '@': resolve('src'), '@static':resolve('static'), '@vuex':resolve('src/vuex'), '@components':resolve('src/components'), '@controller':resolve('src/controller'), '@filters':resolve('src/filters'), '@directive':resolve('src/directive'), '@utils':resolve('src/utils'), '@api':resolve('src/api') } }, //預載入器 module: { rules: [ { test: /\.vue$/, loader: 'vue-loader', options: vueLoaderConfig //通過不同環境, loader 選項引數 }, { 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]') } } ] }, node: { // prevent webpack from injecting useless setImmediate polyfill because Vue // source contains it (although only uses it if it's native). setImmediate: false, // prevent webpack from injecting mocks to Node native modules // that does not make sense for the client dgram: 'empty', fs: 'empty', net: 'empty', tls: 'empty', child_process: 'empty' } }