我有一个要求，我在其中渲染视图，在其中显示表单。在提交表单时，我需要收集表单数据并创建一个文件并将表单数据保存为该文件中的 JSON。我正在使用 React.js、node.js、babel 和 webpack。
在努力实现这一点之后，我发现我必须使用同构或通用 javascript，即在服务器端使用 react 和 render，因为我们不能在客户端使用 fs module。 将此用于服务器端。
我使用以下方法运行它： npm run start
在此之后，我可以在控制台中看到[Object Object]从下面的react组件 (HomePage.js) 的第 1 行打印在控制台上。但是稍后当我访问此页面时，它会出现错误：
'bundle.js:18 未捕获的错误：找不到module“fs”'
我如何将 fs module与 react 一起使用？
以下是代码片段：
webpack.config.js
"use strict";
const debug = process.env.NODE_ENV !== "production";
const webpack = require('webpack');
const path = require('path');
module.exports = {
devtool: debug ? 'inline-sourcemap' : null,
entry: path.join(__dirname, 'src', 'app-client.js'),
devServer: {
inline: true,
port: 3333,
contentBase: "src/static/",
historyApiFallback: true
},
output: {
path: path.join(__dirname, 'src', 'static', 'js'),
publicPath: "/js/",
filename: 'bundle.js'
},
module: {
loaders: [{
test: path.join(__dirname, 'src'),
loader: ['babel-loader'],
query: {
//cacheDirectory: 'babel_cache',
presets: debug ? ['react', 'es2015', 'react-hmre'] : ['react', 'es2015']
}
}]
},
plugins: debug ? [] : [
new webpack.DefinePlugin({
'process.env.NODE_ENV': JSON.stringify(process.env.NODE_ENV)
}),
new webpack.optimize.DedupePlugin(),
new webpack.optimize.OccurenceOrderPlugin(),
new webpack.optimize.UglifyJsPlugin({
compress: { warnings: false },
mangle: true,
sourcemap: false,
beautify: false,
dead_code: true
}),
]
};包.json
{
"name": "sample",
"version": "1.0.0",
"description": "Simple application to showcase how to achieve universal rendering and routing with React and Express.",
"main": "src/server.js",
"scripts": {
"start": "SET NODE_ENV=production&&babel-node src/server.js",
"start-dev": "npm run start-dev-hmr",
"start-dev-single-page": "node_modules/.bin/http-server src/static",
"start-dev-hmr": "webpack-dev-server --progress --inline --hot",
"build": "SET NODE_ENV=production&&webpack -p"
},
"dependencies": {
"babel-cli": "^6.11.4",
"babel-core": "^6.13.2",
"babel-loader": "^6.2.5",
"babel-plugin-react-html-attrs": "^2.0.0",
"babel-preset-es2015": "^6.13.2",
"babel-preset-react": "^6.11.1",
"babel-preset-react-hmre": "^1.1.1",
"ejs": "^2.5.1",
"express": "^4.14.0",
"react": "^15.3.1",
"react-dom": "^15.3.1",
"react-router": "^2.6.1"
},
"devDependencies": {
"http-server": "^0.9.0",
"react-hot-loader": "^1.3.0",
"webpack": "^1.13.2",
"webpack-dev-server": "^1.14.1"
}
}服务器.js
use strict';
import path from 'path';
import { Server } from 'http';
import Express from 'express';
import React from 'react';
import { renderToString } from 'react-dom/server';
import { match, RouterContext } from 'react-router';
import routes from './routes';
import NotFoundPage from './components/NotFoundPage';
//import fs from 'fs';
//console.log("server" + fs);
// initialize the server and configure support for ejs templates
const app = new Express();
const server = new Server(app);
app.set('view engine', 'ejs');
app.set('views', path.join(__dirname, 'views'));
// define the folder that will be used for static assets
app.use(Express.static(path.join(__dirname, 'static')));
// universal routing and rendering
app.get('*', (req, res) => {
match(
{ routes, location: req.url },
(err, redirectLocation, renderProps) => {
//console.log("renderProps "+ Object.values(routes));
//console.log("req.url "+ req.url);
// in case of error display the error message
if (err) {
return res.status(500).send(err.message);
}
// in case of redirect propagate the redirect to the browser
if (redirectLocation) {
return res.redirect(302, redirectLocation.pathname + redirectLocation.search);
}
// generate the React markup for the current route
let markup;
if (renderProps) {
// if the current route matched we have renderProps
markup = renderToString(<RouterContext {...renderProps}/>);
} else {
// otherwise we can render a 404 page
markup = renderToString(<NotFoundPage/>);
res.status(404);
}
// render the index template with the embedded React markup
return res.render('index', { markup });
}
);
});
// start the server
const port = process.env.PORT || 3000;
const env = process.env.NODE_ENV || 'production';
console.log(`Server starting on http://localhost:${port} [${env}]`)
server.listen(port, err => {
if (err) {
return console.error(err);
}
console.info(`Server running on http://localhost:${port} [${env}]`);
});HomePage.js（react组件）
import React from 'react';
import fs from 'fs';
import dateformat from 'dateformat';
console.log("home page" + fs); -- Line 1
class HomePage extends React.Component{
checkDirectory(directory, callback) {
fs.stat(directory, function(err, stats) {
//Check if error defined and the error code is "not exists"
if (err && err.errno === 34) {
//Create the directory, call the callback.
fs.mkdir(directory, callback);
} else {
//just in case there was a different error:
callback(err)
}
});
}
handleClick(){
var obj = JSON.stringify($('#statusForm').serializeArray());
this.checkDirectory("directory/"+currentDate, function(error) {
if(error) {
console.log("oh no!!!", error);
} else {
//Carry on, all good, directory exists / created.
fs.writeFile("directory/"+currentDate+name+".json", obj, function(err) {
if(err) {
return console.log(err);
}
console.log("The file was saved!");
});
console.log("exists");
}
});*/
}
render() {
return (
<div className="container">
<form id="statusForm" className="form-horizontal" >
<div className="form-group">
<label className="control-label col-sm-2" for="names">Select list:</label>
<div className="col-sm-10">
<select name="names" className="form-control" id="names">
<option>Select</option>
<option>abc</option>
<option>xyz</option>
</select>
</div>
</div>
<div className="form-group">
<label className="control-label col-sm-2" for="team">Select list:</label>
<div className="col-sm-10">
<select name="team" className="form-control" id="team">
<option>Select</option>
<option>team 1</option>
<option>team 2</option>
</select>
</div>
</div>
<div className="form-group">
<label className="control-label col-sm-2" for="pwd">Password:</label>
<div className="col-sm-10">
<input type="textarea" className="form-control" id="todayTask" name="todayTask" placeholder="Enter Task"/>
</div>
</div>
<div className="form-group">
<div className="col-sm-offset-2 col-sm-10">
<button type="button" className="btn btn-default" onClick={this.handleClick.bind(this)}>Submit</button>
</div>
</div>
</form>
</div>
);
}
}
export default HomePage;编辑 1：
我进行了更多调查，发现如果我不使用 npm run build 显式构建我的应用程序，而只是更新我的 react 组件，我就不会遇到上述错误。此外，在此之后，如果我将文件创建逻辑直接放在渲染方法中并在刷新页面上成功创建文件。所以观察是它不适用于按钮的 Onclick 并且如果我们刷新页面可以工作。它转到服务器，这就是它以这种方式工作的原因。
编辑2：
通过在我的 webpack 配置中使用 target:'node' 解决了页面刷新问题，但我确实收到了错误：
未捕获的 ReferenceError：需要未定义
在 browser.so 中，直接在 render 方法中的文件创建逻辑将在我们访问页面的那一刻创建文件。无需刷新。
谁能指导我达到我想要的要求的最佳方法是什么？