javascript - 语法错误 : Unexpected token < while using renderToString(

Question

我正在尝试使用 React 和 React-router 进行服务器端渲染。到目前为止，它只是来自各种来源的复制粘贴代码。但是当我尝试使用 Node 运行应用程序时出现语法错误(不是运行时错误)。下面是代码

App.js

'use strict';
require('babel/register');

const express        = require('express');
const http           = require('http');
const handlebars     = require('express-handlebars');
const renderToString = require('react-dom').server;
const match          = require('react-router').match;
const RoutingContext = require('react-router').RoutingContext;
const Routes         = require('./routes');
const app            = express();
var server;

// JSX transpilation
require('node-jsx').install();

// Setting up handlebars
app.engine('.hbs', handlebars({
    extname: '.hbs',
    layoutsDir: 'views/server',
    partialsDir: 'views/server/partials'
}));

app.set('view engine', '.hbs');

// Mount Routes
app.use('*', function (req, res) {
    match({routes: routes, location: req.url}, (error, redirectLocation, renderProps) => {
        if (error) {
          res.status(500).send(error.message)
        } else if (redirectLocation) {
          res.redirect(302, redirectLocation.pathname + redirectLocation.search)
        } else if (renderProps) {
            console.log(renderProps);
            var pageData = {
                serverHtml: renderToString(<RoutingContext {...renderProps} />)
            };
            console.log(pageData);
            res.render('base', pageData);
        } else {
          res.status(404).send('Not found')
        }
    });
});

server = http.createServer(app);

server.listen('3000', () => {
    console.log('Express server listening on port ' + 3000);
});

我在运行 node --harmony app.js 时遇到的错误是

serverHtml: renderToString(<RoutingContext {...renderProps} />)
                                       ^
SyntaxError: Unexpected token <
    at exports.runInThisContext (vm.js:73:16)
    at Module._compile (module.js:443:25)
    at Object.Module._extensions..js (module.js:478:10)
    at Module.load (module.js:355:32)
    at Function.Module._load (module.js:310:12)
    at Function.Module.runMain (module.js:501:10)
    at startup (node.js:129:16)
    at node.js:814:3

我是否需要安装/转换(babelify/jsx)我的代码来处理 JSX 样式标签？但是我在网上的任何教程中都没有找到这样的说法。

我关注的资源

1. React-router(Serverside Rendering)
2. Server Side Rendering by React

Answer 1

注意 - 此方法已弃用。那里有更好的选择。如前所述，require('node-jsx').install() 不再维护，使用 babel 是前进的理想方式。

所以我通过对上面的代码做一些修改来解决这个问题

我删除了以下行，因为它不是必需的

require('babel/register');

然后我没有通过 babel 转译 app.js，而是使用 React.createElement() 更改了 JSX 标签，如下所示:

//serverHtml: renderToString(<RoutingContext {...renderProps} />)
serverHtml: ReactDOM.renderToString(React.createElement(RoutingContext, renderProps))

完整的更新代码如下:

'use strict';

const compression    = require('compression');
const express        = require('express');
const http           = require('http');
const handlebars     = require('express-handlebars');
const path           = require('path');
const React          = require('react');
const ReactDOM       = require('react-dom/server'); // Fixed this
const match          = require('react-router').match;
const RoutingContext = require('react-router').RoutingContext;
const app            = express();
var server;

require('node-jsx').install(); // Not required if you convert the below './routes' file from JSX into js
const Routes = require('./routes');

// Used for Gzipping all the resources
app.use(compression());

// Setting up handlebars
app.engine('.hbs', handlebars({
    extname: '.hbs',
    layoutsDir: 'views/server',
    partialsDir: 'views/server/partials'
}));

app.set('view engine', '.hbs');

// Set path to public assets
app.use(express.static(path.join(__dirname, 'public')));

// Mount Routes
app.use('*', function (req, res) {
    match({routes:Routes, location:req.url}, (error, redirectLocation, renderProps) => {
        if (error) {
          res.status(500).send(error.message)
        } else if (redirectLocation) {
          res.redirect(302, redirectLocation.pathname + redirectLocation.search)
        } else if (renderProps) {
            var pageData = {
                serverHtml: ReactDOM.renderToString(React.createElement(RoutingContext, renderProps))
            };

            res.render('base', pageData);
        } else {
          res.status(404).send('Not found')
        }
    });
});

server = http.createServer(app);

server.listen('3000', () => {
    console.log('Express server listening on port ' + 3000);
});

谢谢:)