前面的话
不论是官网教程,还是官方DEMO,都是从0开始的服务端渲染配置。对于现有项目的服务器端渲染SSR改造,特别是基于vue cli生成的项目,没有特别提及。本文就小火柴的前端小站这个前台项目进行SSR改造
效果
下面是经过SSR改造后的前端小站xiaohuochai.cc的网站效果,github源码地址
概述
【定义】
服务器渲染的Vue应用程序被认为是"同构"或"通用",因为应用程序的大部分代码都可以在服务器和客户端上运行
【优点】
与传统SPA相比,服务器端渲染(SSR)的优势主要在于:
1、更好的 SEO,搜索引擎爬虫抓取工具可以直接查看完全渲染的页面
截至目前,Google 和 Bing 可以很好对同步 JavaScript 应用程序进行索引。但如果应用程序初始展示 loading 菊花图,然后通过 Ajax 获取内容,抓取工具并不会等待异步完成后再行抓取页面内容
2、更快的内容到达时间,特别是对于缓慢的网络情况或运行缓慢的设备
无需等待所有的 JavaScript 都完成下载并执行,才显示服务器渲染的标记,所以用户将会更快速地看到完整渲染的页面,通常可以产生更好的用户体验
思路
下面以官方的SSR服务器端渲染流程图为例,进行概要说明
1、universal Application Code是服务器端和浏览器端通用的代码
2、app.js是应用程序的入口entry,对应vue cli生成的项目的main.js文件
3、entry-client.js是客户端入口,仅运行于浏览器,entry-server.js是服务器端入口,仅运行于服务器
4、entry-client和entry-server这两个文件都需要通过webpack构建,其中entry-client需要通过webpack.server.config.js文件打包,entry-server需要通过webpack.server.config.js文件打包
5、entry-client构建后的client Bundle打包文件是vue-ssr-client-manifest.json,entry-server构建后的server Bundle打包文件是vue-ssr-server-bundle.json
6、server.js文件将客户端打包文件vue-ssr-client-manifest.json、服务器端打包文件vue-ssr-server-bundle.json和HTML模板混合,渲染成HTML
webpack配置
基于vue-cli生成的项目的build目录结构如下
build - build.js - check-versions.js - utils.js - vue-loader.conf.js - webpack.base.conf.js - webpack.dev.conf.js - webpack.prod.conf.js
前面3个文件无需修改,只需修改*.*.conf.js文件
1、修改vue-loader.conf.js,将extract的值设置为false,因为服务器端渲染会自动将CSS内置。如果使用该extract,则会引入link标签载入CSS,从而导致相同的CSS资源重复加载
- extract: isProduction + extract: false
2、修改webpack.base.conf.js
只需修改entry入门配置即可
... module.exports = { context: path.resolve(__dirname, '../'), entry: { - app: './src/main.js' + app: './src/entry-client.js' }, ...
3、修改webpack.prod.conf.js
包括应用vue-server-renderer、去除HtmlWebpackPlugin、增加client环境变量
'use strict' ... + const VueSSRClientPlugin = require('vue-server-renderer/client-plugin') const webpackConfig = merge(baseWebpackConfig, { ... plugins: [ // http://vuejs.github.io/vue-loader/en/workflow/production.html new webpack.DefinePlugin({ 'process.env': env, + 'process.env.VUE_ENV': '"client"' }), ...// 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' - }), ...// copy custom static assets new CopyWebpackPlugin([ { from: path.resolve(__dirname, '../static'), to: config.build.assetsSubDirectory, ignore: ['.*'] } ]), + new VueSSRClientPlugin() ] }) ... module.exports = webpackConfig
4、新增webpack.server.conf.js
const webpack = require('webpack') const merge = require('webpack-merge') const nodeExternals = require('webpack-node-externals') const baseConfig = require('./webpack.base.conf.js') const VueSSRServerPlugin = require('vue-server-renderer/server-plugin') module.exports = merge(baseConfig, { entry: './src/entry-server.js', target: 'node', devtool: 'source-map', output: { libraryTarget: 'commonjs2' }, externals: nodeExternals({ whitelist: /\.css$/ }), plugins: [ new webpack.DefinePlugin({ 'process.env.NODE_ENV': JSON.stringify(process.env.NODE_ENV || 'development'), 'process.env.VUE_ENV': '"server"' }), new VueSSRServerPlugin() ] })
入口配置
在浏览器端渲染中,入口文件是main.js,而到了服务器端渲染,除了基础的main.js,还需要配置entry-client.js和entry-server.js
1、修改main.js
import Vue from 'vue' import Vuex from 'vuex' - import '@/assets/style.css' import App from './App' - import router from './router' + import createRouter from './router' - import store from './store' + import createStore from './store' import async from './utils/async' Vue.use(async) - new Vue({ + export default function createApp() { + const router = createRouter() + const store = createStore() + const app = new Vue({ - el: '#app', router, store, - components: { App }, - template: '<App/>' + render: h => h(App) })+ return { app, router, store } +}
2、新增entry-client.js
后面会介绍到asyncData方法,但是asyncData方法只能用于路由绑定的组件,如果是初始数据则可以直接在entry-client.js中获取
/* eslint-disable */ import Vue from 'vue' import createApp from './main' Vue.mixin({ beforeRouteUpdate (to, from, next) { const { asyncData } = this.$options if (asyncData) { asyncData({ store: this.$store, route: to }).then(next).catch(next) } else { next() } } }) const { app, router, store } = createApp() /* 获得初始数据 */ import { LOAD_CATEGORIES_ASYNC } from '@/components/Category/module' import { LOAD_POSTS_ASYNC } from '@/components/Post/module' import { LOAD_LIKES_ASYNC } from '@/components/Like/module' import { LOAD_COMMENTS_ASYNC } from '@/components/Comment/module' import { LOAD_USERS_ASYNC } from '@/components/User/module' (function getInitialData() { const { postCount, categoryCount, userCount, likeCount, commentCount } = store.getters const { dispatch } = store // 获取类别信息 !categoryCount && dispatch(LOAD_CATEGORIES_ASYNC), // 获取文章信息 !postCount && dispatch(LOAD_POSTS_ASYNC), // 获取点赞信息 !likeCount && dispatch(LOAD_LIKES_ASYNC), // 获取评论信息 !commentCount && dispatch(LOAD_COMMENTS_ASYNC), // 获取用户信息 !userCount && dispatch(LOAD_USERS_ASYNC) })() if (window.__INITIAL_STATE__) { store.replaceState(window.__INITIAL_STATE__) } router.onReady(() => { router.beforeResolve((to, from, next) => { const matched = router.getMatchedComponents(to) const prevMatched = router.getMatchedComponents(from) let diffed = false const activated = matched.filter((c, i) => { return diffed || (diffed = (prevMatched[i] !== c)) }) if (!activated.length) { return next() } Promise.all(activated.map(c => { if (c.asyncData) { return c.asyncData({ store, route: to }) } })).then(() => { next() }).catch(next) }) app.$mount('#root') })
3、新增entry-sever.js
/* eslint-disable */ import createApp from './main' export default context => new Promise((resolve, reject) => { const { app, router, store } = createApp() router.push(context.url) router.onReady(() => { const matchedComponents = router.getMatchedComponents() if (!matchedComponents.length) { }) } Promise.all(matchedComponents.map(Component => { if (Component.asyncData) { return Component.asyncData({ store, route: router.currentRoute }) } })).then(() => { context.state = store.state resolve(app) }).catch(reject) }, reject) })
组件修改
由于代码需要在服务器端和浏览器端共用,所以需要修改组件,使之在服务器端运行时不会报错
1、修改router路由文件,给每个请求一个新的路由router实例
import Vue from 'vue' import Router from 'vue-router' Vue.use(Router) + export default function createRouter() { - export default new Router({+ return new Router({ mode: 'history', routes: [ { path: '/', component: () => import(/* webpackChunkName:'home' */ '@/components/Home/Home'), name: 'home', meta: { index: } }, ... ] })+}
2、修改状态管理vuex文件,给每个请求一个新的vuex实例
import Vue from 'vue' import Vuex from 'vuex' import auth from '@/components/User/module' ... Vue.use(Vuex) + export default function createStore() { - export default new Vuex.Store({+ return new Vuex.Store({ modules: { auth, ... } })+}
3、使用asyncData方法来获取异步数据
要特别注意的是,由于asyncData只能通过路由发生作用,使用是非路由组件的异步数据获取最好移动到路由组件中
如果要通过asyncData获取多个数据,可以使用Promise.all()方法
asyncData({ store }) { const { dispatch } = store return Promise.all([ dispatch(LOAD_CATEGORIES_ASYNC), dispatch(LOAD_POSTS_ASYNC) ]) }
如果该异步数据是全局通用的,可以在entry-client.js方法中直接获取
将TheHeader.vue通用头部组件获取异步数据的代码移动到entry-client.js方法中进行获取
// TheHeader.vue computed: { ... - ...mapGetters([ - 'postCount', - 'categoryCount', - 'likeCount', - 'commentCount', - 'userCount' - ]) }, - mounted() { // 获取异步信息 - this.loadAsync() ... - }, ... methods: { - loadAsync() { - const { postCount, categoryCount, userCount, likeCount, commentCount } = this - const { dispatch } = this.$store - // 获取类别信息 - !categoryCount && dispatch(LOAD_CATEGORIES_ASYNC) - // 获取文章信息 - !postCount && dispatch(LOAD_POSTS_ASYNC) - // 获取点赞信息 - !likeCount && dispatch(LOAD_LIKES_ASYNC) - // 获取评论信息 - !commentCount && dispatch(LOAD_COMMENTS_ASYNC) - // 获取用户信息 - !userCount && dispatch(LOAD_USERS_ASYNC) - },
将Post.vue中的异步数据通过asyncData进行获取
// post.vue ... export default { + asyncData({ store, route }) { + return store.dispatch(LOAD_POST_ASYNC, { id: route.params.postid }) + }, ... - mounted() { - this.$store.dispatch(LOAD_POST_ASYNC, { id: this.postId }) - }, ...
4、将全局css从main.js移动到App.vue中的内联style样式中,因为main.js中未设置css文件解析
// main.js - import '@/assets/style.css' // App.vue ... <style module lang="postcss"> ... </style>
5、由于post组件的模块module.js中需要对数据通过window.atob()方法进行base64解析,而nodeJS环境下无window对象,会报错。于是,代码修改如下
// components/Post/module - text: decodeURIComponent(escape(window.atob(doc.content))) + text: typeof window === 'object' ? decodeURIComponent(escape(window.atob(doc.content))) : ''
服务器配置
1、在根目录下,新建server.js文件
由于在webpack中去掉了HTMLWebpackPlugin插件,而是通过nodejs来处理模板,同时也就缺少了该插件设置的HTML文件压缩功能
需要在server.js文件中安装html-minifier来实现HTML文件压缩
const express = require('express') const fs = require('fs') const path = require('path') const { createBundleRenderer } = require('vue-server-renderer') const { minify } = require('html-minifier') const app = express() const resolve = file => path.resolve(__dirname, file) const renderer = createBundleRenderer(require('./dist/vue-ssr-server-bundle.json'), { runInNewContext: false, template: fs.readFileSync(resolve('./index.html'), 'utf-8'), clientManifest: require('./dist/vue-ssr-client-manifest.json'), basedir: resolve('./dist') }) app.use(express.static(path.join(__dirname, 'dist'))) app.get('*', (req, res) => { res.setHeader('Content-Type', 'text/html') const handleError = err => { if (err.url) { res.redirect(err.url) } ) { res.status().send('404 | Page Not Found') } else { res.status().send('500 | Internal Server Error') console.error(`error during render : ${req.url}`) console.error(err.stack) } } const context = { title: '小火柴的前端小站', url: req.url } renderer.renderToString(context, (err, html) => { console.log(err) if (err) { return handleError(err) } res.send(minify(html, { collapseWhitespace: true, minifyCSS: true})) }) }) app.on('error', err => console.log(err)) app.listen(, () => { console.log(`vue ssr started at localhost: `) })
2、修改package.json文件
- "build": "node build/build.js", + "build:client": "node build/build.js", + "build:server": "cross-env NODE_ENV=production webpack --config build/webpack.server.conf.js --progress --hide-modules", + "build": "rimraf dist && npm run build:client && npm run build:server",
3、修改index.html文件
<!DOCTYPE html> <html> <head> <meta charset="utf-8"> <meta name="viewport" content="width=device-width,initial-scale=1.0,user-scalable=no"> <link rel="shortcut icon" href="/static/favicon.ico"> <title>小火柴的蓝色理想</title> </head> <body> <!--vue-ssr-outlet--> </body> </html>
4、取消代理
如果继续使用代理如/api代理到后端接口,则可能会报如下错误
error:connect ECONNREFUSED
直接写带有http的后端接口地址即可
const API_HOSTNAME = 'http://192.168.1.103:4000'
测试
1、安装依赖包
cnpm install --save-dev vue-server-renderer
2、构建
npm run build
3、运行
node server.js
点击右键,查看网页源代码。结果如下,说明网站已经实现了服务器端渲染
部署
【pm2】
由于该网站需要守护nodejs程序,使用pm2部署较为合适
在项目根目录下,新建一个ecosystem.json文件,内容如下
{ "apps" : [{ "name" : "blog-www", "script" : "./index.js", "env": { "COMMON_VARIABLE": "true" }, "env_production" : { "NODE_ENV": "production" } }], "deploy" : { "production" : { "user" : "xxx", "host" : ["1.2.3.4"], ", "ref" : "origin/master", "repo" : "git@github.com:littlematch0123/blog-client.git", "path" : "/home/xxx/www/mall", "post-deploy" : "source ~/.nvm/nvm.sh && cnpm install && pm2 startOrRestart ecosystem.json --env production", "ssh_options": "StrictHostKeyChecking=no", "env" : { "NODE_ENV": "production" } } } }
【CDN】
由于项目实际上既有静态资源,也有nodeJS程序。因此,最好把静态资源上传到七牛CDN上
自行选择服务器的一个目录,新建upload.js文件
var fs = require('fs'); var qiniu = require('qiniu'); var accessKey = 'xxx'; var secretKey = 'xxx'; var mac = new qiniu.auth.digest.Mac(accessKey, secretKey); var staticPath = '/home/www/blog/client/source/'; var prefix = 'client/static'; var bucket = 'static'; var config = new qiniu.conf.Config(); config.zone = qiniu.zone.Zone_z1; var formUploader = new qiniu.form_up.FormUploader(config); var putExtra = new qiniu.form_up.PutExtra(); putExtra = null; // 一定要将putExtra设置为null,否则会出现所有文件类别都被识别为第一个文件的类型的情况 // 文件上传方法 function uploadFile (localFile) { // 配置上传到七牛云的完整路径 const key = localFile.replace(staticPath, prefix) const options = { scope: bucket + ":" + key, } const putPolicy = new qiniu.rs.PutPolicy(options) // 生成上传凭证 const uploadToken = putPolicy.uploadToken(mac) // 上传文件 formUploader.putFile(uploadToken, key, localFile, putExtra, function(respErr, respBody, respInfo) { if (respErr) throw respErr ) { console.log(respBody); } else { console.log(respInfo.statusCode); console.log(respBody); } }) } // 目录上传方法 function uploadDirectory (dirPath) { fs.readdir(dirPath, function (err, files) { if (err) throw err // 遍历目录下的内容 files.forEach(item => { let path = `${dirPath}/${item}` fs.stat(path, function (err, stats) { if (err) throw err // 是目录就接着遍历 否则上传 if (stats.isDirectory()) uploadDirectory(path) else uploadFile(path, item) }) }) }) } fs.exists(staticPath, function (exists) { if (!exists) { console.log('目录不存在!') } else { console.log('开始上传...') uploadDirectory(staticPath) } })
【post-deploy】
然后,修改ecosystem.json文件中的post-deploy项
"source ~/.nvm/nvm.sh && cnpm install && npm run build && node /home/xiaohuochai/blog/client/upload.js&& pm2 startOrRestart ecosystem.json --env production",
但是,经过实际测试,在服务器端进行构建build,极其容易造成服务器死机。于是,还是在本地构建完成后,上传dist文件到服务器再进行相关操作
"source ~/.nvm/nvm.sh && cnpm install && node /home/xiaohuochai/blog/client/upload.js&& pm2 startOrRestart ecosystem.json --env production"
修改项目的静态资源地址为CDN地址,API地址为服务器API地址
// config/index.js assetsPublicPath: 'https://static.xiaohuochai.site/client/' // src/constants/API.js const API_HOSTNAME = 'https://api.xiaohuochai.cc'
【nginx】
如果要使用域名对项目进行访问,还需要进行nginx配置
upstream client { server ; } server{ listen ; server_name www.xiaohuochai.cc xiaohuochai.cc; https://www.xiaohuochai.cc$request_uri; } server{ listen http2; server_name www.xiaohuochai.cc xiaohuochai.cc; ssl on; ssl_certificate /home/blog/client/crt/www.xiaohuochai.cc.crt; ssl_certificate_key /home/blog/client/crt/www.xiaohuochai.cc.key; ssl_session_timeout 5m; ssl_ciphers ECDHE-RSA-AES128-GCM-SHA256:ECDHE:ECDH:AES:HIGH:!NULL:!aNULL:!MD5:!ADH:!RC4; ssl_protocols TLSv1 TLSv1. TLSv1.; ssl_prefer_server_ciphers on; if ($host = 'xiaohuochai.cc'){ rewrite ^/(.*)$ http://www.xiaohuochai.cc/$1 permanent; } location / { expires 7d; add_header Content-Security-Policy "default-src 'self' https://static.xiaohuochai.site; connect-src https://api.xiaohuochai.cc; script-src 'self' 'unsafe-inline' 'unsafe-eval' https://static.xiaohuochai.site ; img-src 'self' data: https://pic.xiaohuochai.site https://static.xiaohuochai.site; style-src 'self' 'unsafe-inline' https://static.xiaohuochai.site; frame-src https://demo.xiaohuochai.site https://xiaohuochai.site https://www.xiaohuochai.site;"; proxy_set_header X-Real-IP $remote_addr; proxy_set_header X-Forward-For $proxy_add_x_forwarded_for; proxy_set_header Host $http_host; proxy_set_header X-Nginx-Proxy true; proxy_pass http://client; proxy_redirect off; } }
浏览器渲染
官网的代码中,如果使用开发环境development,则需要进行相当复杂的配置
能否应用当前的webpack.dev.conf.js来进行开发呢?完全可以,开发环境中使用浏览器端渲染,生产环境中使用服务器端渲染
需要做出如下三点更改:
1、更改API地址,开发环境使用webpack代理,生产环境使用上线地址
// src/constants/API let API_HOSTNAME if (process.env.NODE_ENV === 'production') { API_HOSTNAME = 'https://api.xiaohuochai.cc' } else { API_HOSTNAME = '/api' }
2、在index.html同级目录下,新建一个index.template.html文件,index.html是开发环境的模板文件,index.template.html是生产环境的模板文件
// index.html <body> <div id="root"></div> </body> // index.template.html <body> <!--vue-ssr-outlet--> </body>
3、更改服务器端入口文件server.js的模板文件为index.template.html
// server.js const renderer = createBundleRenderer(require('./dist/vue-ssr-server-bundle.json'), { runInNewContext: false, template: fs.readFileSync(resolve('./index.template.html'), 'utf-8'), clientManifest: require('./dist/vue-ssr-client-manifest.json'), basedir: resolve('./dist') })
经过简单的更改,即可实现开发环境使用浏览器端渲染,生产环境使用服务器端渲染的效果