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Require not defined in script tag

I am writing an electron app using react as for the UI and webpack for bundling. Webpack is configured right now for the react part of the application as follows:
const path = require('path');
const HtmlWebPackPlugin = require("html-webpack-plugin");
const CopyWebpackPlugin = require('copy-webpack-plugin')
module.exports = {
mode: 'development',
entry: './src/index.tsx',
target:'node',
output: {
filename: '[name].bundle.js',
path: path.join(__dirname, 'build')
},
module: {
rules: [
{
test: /\.tsx?$/,
exclude: /node_modules/,
use: {
loader: 'ts-loader'
}
},
{
test: /\.(png|jpg|gif)$/,
use: [
{
loader: 'file-loader'
}
]
},
{
test: /\.css$/,
loader: 'css-loader',
options: {
sourceMap: true,
},
},
{
test: /\.scss$/,
use: [{
loader: "css-loader", options: {
sourceMap: true
}
}, {
loader: "sass-loader", options: {
sourceMap: true
}
}]
}
]
},
resolve: {
extensions: ['.tsx', '.ts', '.js']
},
plugins: [
new HtmlWebPackPlugin({
template: "./index.html",
filename: "./index.html"
}),
new CopyWebpackPlugin([{ from: 'public',ignore: ['*.html'] }])
],
devtool: 'eval-source-map'
}
In my index.html I need to use the following script tag for electron's rendering process :
<script>
require('build/bundle.js')
</script>
When I run webpack-dev-server everything compiles without error, but when I open chrome dev tools I see this error :
Uncaught ReferenceError: require is not defined
at (index):12
I had to target node in my webpack.config to make electron work so I assume the require function works in browser as well since if I were to create an electron app in a pure node.js environment(without webpack and react) it works without any additional configuration. So I guess there is an issue with my webpack configuration, but I can't find any useful resource online unfortunately. Can anyone help me out? Thanks in advance!

Electron is basically a chromium browser connected to a node process through « IPC ».
This means you don’t have require available in the browser.
You need to import your script like this:
<script src="/build/bundle.js"></script>
And also you need to change the target from node to electron-renderer for the browser code.
If you also need to build code for the node side you need to add the electron-main target.
See https://webpack.js.org/configuration/

Webpack output bundle larger than expected

The only thing I have in my entry JS file is:
import $ from 'jquery';
The jQuery JS file has the size of 29.5kb from jsdelivr.
My entry, that only includes jQuery, and nothing else, has the size of 86kb.
webpack.config.js
const path = require('path');
const ExtractTextPlugin = require("extract-text-webpack-plugin");
const UglifyJsPlugin = require('uglifyjs-webpack-plugin')
module.exports = {
entry: './src/js/scripts.js',
output: {
publicPath: "./dist/",
path: path.join(__dirname, "dist/js/"),
filename: "bundle.js"
},
watch: true,
module: {
rules: [
{
test: /\.js$/,
exclude: /node_modules/,
loader: "babel-loader",
query: {
presets: [
['env', { loose:true, modules:false }],
'stage-2'
],
plugins: [
['transform-react-jsx', { pragma:'h' }]
]
}
},
{
test: /\.pug$/,
use: [
"file-loader?name=[name].html&outputPath=../dist",
"extract-loader",
"html-loader",
"pug-html-loader"
]
},
{
test: /\.scss$/,
use: ExtractTextPlugin.extract({
use: ['css-loader?url=false', 'sass-loader']
})
},
]
},
resolve: {
alias: {
"TweenMax": path.resolve('node_modules', 'gsap/src/uncompressed/TweenMax.js'),
"TimelineMax": path.resolve('node_modules', 'gsap/src/uncompressed/TimelineMax.js'),
"animation.gsap": path.resolve('node_modules', 'scrollmagic/scrollmagic/uncompressed/plugins/animation.gsap.js'),
}
},
plugins: [
new ExtractTextPlugin('../css/main.css'),
new UglifyJsPlugin({
test: /\.js($|\?)/i
})
],
stats: {
warnings: false
}
};
I should also mention, that going into the output bundle.js it still has the jQuery comments.
jQuery JavaScript Library v3.3.1
https://jquery.com/ ...
Even though I'm calling webpack with the -p argument and have the UglifyJS plugin, but the rest of the file is minified and mangled. Any ideas?
Thanks!

Try to copy and paste minified jquery from your link. It's has size of 86.9 kb.
This link also show that jquery v3 minified file size is also around 80kb.
So you already have correct setup. Maybe your 29.5kb file size is minified+gzipped file.

The 29.5kb file size is definitely the minified+gzipped version as per the link Niyoko posted.
I would also recommend checking out Fuse-Box It brought down our project size from over 1mb to under 200kb (Vendor and App bundles combined). Very easy to get going as well and it is TypeScript first :) It takes the best features from a number of the more popular bundlers and brings them together and builds on those features.

Webpack bundles tests (enzyme / jest) in the production env

I have issue with Webpack building production bundle with test files + test libs included.
In this case it is Enzyme and Jest which we use.
Webpack version 3.10.0
Webpack.build.js
const path = require('path');
const webpack = require('webpack');
const UglifyJsPlugin = require('uglifyjs-webpack-plugin');
module.exports = function() {
return {
entry: './src/index.js',
output: {
path: path.resolve(__dirname, '../build'),
filename: 'bundle.js',
},
module: {
rules: [
{
test: /\.js$/,
exclude: [
/node_modules/,
/__snapshots__/,
/test-util/,
],
loader: 'babel-loader'
},
{
test: /\.scss$/,
use: [
{
loader: 'isomorphic-style-loader'
},
{
loader: 'css-loader'
},
{
loader: 'sass-loader'
}
]
},
]
},
plugins: [
new UglifyJsPlugin(),
new webpack.DefinePlugin({
'process.env': {
'NODE_ENV': JSON.stringify(process.env.NODE_ENV),
}
}),
]
}
};
Here is the file structure
I have tried to workaround the issue by placing Enzyme as external resource in webpack.
externals: {
'enzyme': 'enzyme',
'enzyme-adapter-react-16': 'enzyme-adapter-react-16',
}
That does exclude it from build but (it is workaround) it still builds the snapshot files
I have tried to make "test" regex of babel-loader more specific and exclude test files but it failed.
This is new project and I spent whole day trying to make it bundle only what is necesary. Drained all of my know-how, my google know-how and know-how of the poeple I know or I work with. Hope that SO will be smarter :)

Still getting 'Symbol' is undefined' error even after adding babel-polyfill in my webpack

https://babeljs.io/docs/usage/polyfill/#usage-in-browser
I did not understand the lines on the documentation page under:
Usage in Browser heading
can someone help me with what else is required:
Below are my code snippets:
I'm using storybook as a boilerplate:
webpack.config.js file:
entry: [
'babel-polyfill',
require.resolve('react-dev-utils/webpackHotDevClient'),
paths.appIndexJs
]
index.js file:
import 'babel-polyfill';
import React from 'react';
Is there some other files also where I need to add babel-polyfill related code.
require('babel-polyfill');
var path = require('path');
var autoprefixer = require('autoprefixer');
var webpack = require('webpack');
var HtmlWebpackPlugin = require('html-webpack-plugin');
var CaseSensitivePathsPlugin = require('case-sensitive-paths-webpack-plugin');
var InterpolateHtmlPlugin = require('react-dev-utils/InterpolateHtmlPlugin');
var WatchMissingNodeModulesPlugin = require('react-dev-utils/WatchMissingNodeModulesPlugin');
var getClientEnvironment = require('./env');
var paths = require('./paths');
var publicPath = '/';
var publicUrl = '';
var env = getClientEnvironment(publicUrl);
module.exports = {
devtool: 'cheap-module-source-map',
entry: ['babel-polyfill',
require.resolve('react-dev-utils/webpackHotDevClient'),
require.resolve('./polyfills'),
paths.appIndexJs
],
output: {
path: paths.appBuild,
pathinfo: true,
filename: 'static/js/bundle.js',
publicPath: publicPath
},
resolve: {
fallback: paths.nodePaths,
extensions: ['.js', '.json', '.jsx', ''],
alias: {
'react-native': 'react-native-web'
}
},
module: {
// First, run the linter.
// It's important to do this before Babel processes the JS.
preLoaders: [{
test: /\.(js|jsx)$/,
loader: 'eslint',
include: paths.appSrc,
}],
loaders: [{
exclude: [/\.html$/, /\.(js|jsx)$/, /\.css$/, /\.json$/],
loader: 'url',
query: {
limit: 10000,
name: 'static/media/[name].[hash:8].[ext]'
}
},
// Process JS with Babel.
{
test: /\.(js|jsx)$/,
include: paths.appSrc,
loader: 'babel',
query: {
cacheDirectory: true
}
}, {
test: /\.css$/,
loader: 'style!css?importLoaders=1!postcss'
}, {
test: /\.json$/,
loader: 'json'
}
]
},
// We use PostCSS for autoprefixing only.
postcss: function() {
return [
autoprefixer({
browsers: ['>1%', 'last 4 versions', 'Firefox ESR', 'not ie < 9', // React doesn't support IE8 anyway
]
}),
];
},
plugins: [
new InterpolateHtmlPlugin({
PUBLIC_URL: publicUrl
}),
new HtmlWebpackPlugin({
inject: true,
template: paths.appHtml,
}),
new webpack.DefinePlugin(env),
new webpack.HotModuleReplacementPlugin(),
new CaseSensitivePathsPlugin(),
new WatchMissingNodeModulesPlugin(paths.appNodeModules)
],
node: {
fs: 'empty',
net: 'empty',
tls: 'empty'
}
};

There are two ways to get this code into your browser.
1 - Include the babel-polyfill module in the webpack bundle
2 - Load it as an external script in your html
Webpack - adding bundle dependencies with entry arrays
Put an array as the entry point to make the babel-polyfill module available to your bundle as an export.
With webpack.config.js, add babel-polyfill to your entry array.
The webpack docs explain how an entry array is handled:
What happens when you pass an array to entry? Passing an array of file
paths to the entry property creates what is known as a "multi-main
entry". This is useful when you would like to inject multiple
dependent files together and graph their dependencies into one
"chunk".
Webpack.config.js
require("babel-polyfill");
var config = {
devtool: 'cheap-module-eval-source-map',
entry: {
main: [
// configuration for babel6
['babel-polyfill', './src/js/main.js']
]
},
}
Alternative to Webpack - load babel-polyfill as an external script in the browser html
The alternative to using webpack would mean including the module as an external script in your html. It will then be available to code in the browser but the webpack bundle won't be directly aware of it.
<script type="text/javascript" src="https://cdnjs.cloudflare.com/ajax/libs/babel-polyfill/6.22.0/polyfill.js"></script>

Import Javascript library globally via Webpack

I am trying to remove script tags for javascript libraries from my html, and so have removed underscore.js from a template page.
To replace this, within my index.js (webpack entry point), I have the following
import 'underscore';
The size of the webpack outputted bundle.js file increases by 50k when I do this, so I know that the library is in bundle.js. However, underscore is not available when I try to use it in the console on a page which has the bundle.js included.
Any thoughts would be appreciated.
const webpack = require('webpack');
const path = require('path');
const precss = require('precss');
const autoprefixer = require('autoprefixer');
const ExtractTextPlugin = require('extract-text-webpack-plugin');
const postcssImport = require('postcss-import');
module.exports = {
context: __dirname + '/frontend',
devtool: 'source-map',
entry: './index.js',
output: {
filename: 'bundle.js',
path: path.join(__dirname, './static'),
},
module: {
loaders: [
{ test: /\.js$/, loader: 'babel', exclude: /node_modules/, query: { presets: ['es2015'] } },
{ test: /\.css$/, loader: ExtractTextPlugin.extract('style', 'css?sourceMap&importLoaders=1!postcss') },
],
},
vendor: [
'underscore',
],
plugins: [
new ExtractTextPlugin('si-styles.css'),
new webpack.ProvidePlugin({
underscore: 'underscore',
}),
],
postcss: function(webpack) {
return [
postcssImport({ addDependencyTo: webpack }), // Must be first item in list
precss,
autoprefixer({ browsers: ['last 2 versions'] }),
];
},
};

In order to achieve that you can use this webpack plugin:
new webpack.ProvidePlugin({
underscore: "underscore"
})
by the way it is not necessary that you import the library in the index file of your directory. You will have access to the library also specifying a new entry point in your webpack config file.. You could then put all your vendor code in a vendor.js boundle like so:
entry: {
main: [
'./app/js/main.js'
],
vendor: [
'underscore',
'lodash',
'my-awesome-library!'
]
}
UPDATE: There is a very good tutorial in how to use webpack in production on egghead.io.. Try to check it out!