摘要：中可以使用注入變量訪(fǎng)問(wèn)環(huán)境變量中的配置信息向全局樣式傳入共享的全局變量在中引用添加兼容在中添加配置完整配置持續(xù)更新中揭秘系列

√ 配置多環(huán)境變量

√ 配置基礎(chǔ) vue.config.js

√ 配置 proxy 跨域

√ 修復(fù) HMR(熱更新)失效

√ 修復(fù) Lazy loading routes Error： Cyclic dependency

√ 添加別名alias

√ 壓縮圖片

√ 自動(dòng)生成雪碧圖

√ 去除多余無(wú)效的 css

√ 添加打包分析

√ 配置 externals 引入cdn資源

√ 刪除moment語(yǔ)言包

√ 去掉 console.log

√ 利用splitChunks多帶帶打包第三方模塊

√ 開(kāi)啟 gzip 壓縮

√ 為 sass 提供全局樣式，以及全局變量

√ 為 stylus 提供全局變量

√ 預(yù)渲染prerender-spa-plugin

√ 添加 IE 兼容

√ 文件上傳 ali oss

√ 完整依賴(lài)

??通過(guò)在package.json里的scripts配置項(xiàng)中添加--mode xxx來(lái)選擇不同環(huán)境

??在項(xiàng)目根目錄中新建.env, .env.production, .env.analyz等文件

??只有以 VUE_APP_ 開(kāi)頭的變量會(huì)被 webpack.DefinePlugin 靜態(tài)嵌入到客戶(hù)端側(cè)的包中，代碼中可以通過(guò)process.env.VUE_APP_BASE_API訪(fǎng)問(wèn)

??NODE_ENV 和 BASE_URL 是兩個(gè)特殊變量，在代碼中始終可用

.env serve默認(rèn)的環(huán)境變量

NODE_ENV = "development"
VUE_APP_BASE_API = "https://demo.cn/api"
VUE_APP_SRC = "https://wechat-timg.oss-cn-hangzhou.aliyuncs.com/demo"

.env.production build默認(rèn)的環(huán)境變量

NODE_ENV = "production"

VUE_APP_BASE_API = "https://demo.com/api"
VUE_APP_SRC = "https://img-wechat.oss-cn-hangzhou.aliyuncs.com/demo"

.env.analyz 用于webpack-bundle-analyzer打包分析

NODE_ENV = "production"
IS_ANALYZ = "analyz"

VUE_APP_BASE_API = "https://demo.com/api"
VUE_APP_SRC = "https://img-wechat.oss-cn-hangzhou.aliyuncs.com/demo"

??修改package.json

"scripts": {
  "serve": "vue-cli-service serve",
  "build": "vue-cli-service build",
  "analyz": "vue-cli-service build --mode analyz",
  "lint": "vue-cli-service lint"
}

const IS_PROD = ["production", "prod"].includes(process.env.NODE_ENV);

module.exports = {
  baseUrl: "./", // 默認(rèn)"/"，部署應(yīng)用包時(shí)的基本 URL
  outputDir: process.env.outputDir || "dist", // "dist", 生產(chǎn)環(huán)境構(gòu)建文件的目錄
  assetsDir: "",  // 相對(duì)于outputDir的靜態(tài)資源(js、css、img、fonts)目錄
  lintOnSave: false,
  runtimeCompiler: true, // 是否使用包含運(yùn)行時(shí)編譯器的 Vue 構(gòu)建版本
  productionSourceMap: false,  // 生產(chǎn)環(huán)境的 source map
  parallel: require("os").cpus().length > 1,
  pwa: {}
};

const IS_PROD = ["production", "prod"].includes(process.env.NODE_ENV);
module.exports = {
    devServer: {
        // overlay: {
        //   warnings: true,
        //   errors: true
        // },
        open: IS_PROD,
        host: "0.0.0.0",
        port: 8000,
        https: false,
        hotOnly: false,
        proxy: {
          "/api": {
            target: process.env.VUE_APP_BASE_API || "http://127.0.0.1:8080",
            changeOrigin: true
          }
        }
    }
}

module.exports = {
    chainWebpack: config => {
        // 修復(fù)HMR
        config.resolve.symlinks(true);
    }
}

const path =  require("path");
const resolve = (dir) => path.join(__dirname, dir);
const IS_PROD = ["production", "prod"].includes(process.env.NODE_ENV);

module.exports = {
    chainWebpack: config => {
        // 添加別名
        config.resolve.alias
          .set("@", resolve("src"))
          .set("assets", resolve("src/assets"))
          .set("components", resolve("src/components"))
          .set("layout", resolve("src/layout"))
          .set("base", resolve("src/base"))
          .set("static", resolve("src/static"));
    }
}

const BundleAnalyzerPlugin = require("webpack-bundle-analyzer").BundleAnalyzerPlugin;

module.exports = {
    chainWebpack: config => {
        // 打包分析
        if (process.env.IS_ANALYZ) {
          config.plugin("webpack-report")
            .use(BundleAnalyzerPlugin, [{
              analyzerMode: "static",
            }]);
        }
    }
}

??防止將某些 import 的包(package)打包到 bundle 中，而是在運(yùn)行時(shí)(runtime)再去從外部獲取這些擴(kuò)展依賴(lài)

module.exports = {
    configureWebpack: config => {
        config.externals = {
          "vue": "Vue",
          "element-ui": "ELEMENT",
          "vue-router": "VueRouter",
          "vuex": "Vuex",
          "axios": "axios"
        }
    }
}

方法一：

const UglifyJsPlugin = require("uglifyjs-webpack-plugin");
module.exports = {
    configureWebpack: config => {
        if (IS_PROD) {
            const plugins = [];
            plugins.push(
                new UglifyJsPlugin({
                    uglifyOptions: {
                        compress: {
                            warnings: false,
                            drop_console: true,
                            drop_debugger: false,
                            pure_funcs: ["console.log"]//移除console
                        }
                    },
                    sourceMap: false,
                    parallel: true
                })
            );
            config.plugins = [
                ...config.plugins,
                ...plugins
            ];
        }
    }
}

方法二：使用babel-plugin-transform-remove-console插件

npm i --save-dev babel-plugin-transform-remove-console

在babel.config.js中配置

const plugins = [];
if(["production", "prod"].includes(process.env.NODE_ENV)) {  
  plugins.push("transform-remove-console")
}

module.exports = {
  presets: [["@vue/app",{"useBuiltIns": "entry"}]],
  plugins: plugins
};

npm i --save-dev compression-webpack-plugin

const CompressionWebpackPlugin = require("compression-webpack-plugin");
const productionGzipExtensions = /.(js|css|json|txt|html|ico|svg)(?.*)?$/i;

module.exports = {
    configureWebpack: config => {
        if (IS_PROD) {
            const plugins = [];
            plugins.push(
                new CompressionWebpackPlugin({
                    filename: "[path].gz[query]",
                    algorithm: "gzip",
                    test: productionGzipExtensions,
                    threshold: 10240,
                    minRatio: 0.8
                })
            );
            config.plugins = [
                ...config.plugins,
                ...plugins
            ];
        }
    }
}

??還可以開(kāi)啟比gzip體驗(yàn)更好的Zopfli壓縮詳見(jiàn)https://webpack.js.org/plugins/compression-webpack-plugin

npm i --save-dev @gfx/zopfli brotli-webpack-plugin

const CompressionWebpackPlugin = require("compression-webpack-plugin");
const zopfli = require("@gfx/zopfli");
const BrotliPlugin = require("brotli-webpack-plugin");
const productionGzipExtensions = /.(js|css|json|txt|html|ico|svg)(?.*)?$/i;

module.exports = {
    configureWebpack: config => {
        if (IS_PROD) {
            const plugins = [];
            plugins.push(
                new CompressionWebpackPlugin({
                    algorithm(input, compressionOptions, callback) {
                      return zopfli.gzip(input, compressionOptions, callback);
                    },
                    compressionOptions: {
                      numiterations: 15
                    },
                    minRatio: 0.99,
                    test: productionGzipExtensions
                })
            );
            plugins.push(
                new BrotliPlugin({
                    test: productionGzipExtensions,
                    minRatio: 0.99
                })
            );
            config.plugins = [
                ...config.plugins,
                ...plugins
            ];
        }
    }
}

??可以通過(guò)在main.js中Vue.prototype.$src = process.env.VUE_APP_SRC;掛載環(huán)境變量中的配置信息，然后在js中使用$src訪(fǎng)問(wèn)。

??css中可以使用注入sass變量訪(fǎng)問(wèn)環(huán)境變量中的配置信息

module.exports = {
    css: {
        modules: false,
        extract: IS_PROD,
        sourceMap: false,
        loaderOptions: {
          sass: {
            // 向全局sass樣式傳入共享的全局變量
            data: `@import "~assets/scss/variables.scss";$src: "${process.env.VUE_APP_SRC}";`
          }
        }
    }
}

在scss中引用

.home {
    background: url($src + "/images/500.png");
}

npm i --save @babel/polyfill

??在main.js中添加

import "@babel/polyfill";

配置babel.config.js

const plugins = [];

module.exports = {
  presets: [["@vue/app",{"useBuiltIns": "entry"}]],
  plugins: plugins
};

???揭秘vue系列???