Develop Reference

Webpack sideEffects wont remove unused function

In the babel-loader iam declaring side-effects to false which means that any unused function should me removed from the bundle. But in my case logFour function remains.
util.js
export function logThree() {
console.log(3);
}
export function logFour() {
console.log(4);
}
logThree();
logFour();
index.js
import { logThree } from "./util";
logThree();
bundle.js
(() => {
"use strict";
function o() {
console.log(3);
}
o(), console.log(4), o();
})();
webpack
module.exports = {
mode: "production",
entry: ["./src/index"],
devtool: "source-map",
output: {
path: path.resolve("dist/"),
publicPath: "/public/assets/",
filename: "main.js",
},
optimization: {
usedExports: true,
},
devServer: {
contentBase: "./src",
},
resolve: {
extensions: [".js"],
},
module: {
rules: [
{
test: /\.m?js$/,
exclude: /node_modules/,
use: {
loader: "babel-loader",
},
sideEffects: false,
},
],
},
};

First, there is no such option sideEffects: false inside webpack config. You should put it in package.json.
Second, based on your probably copy-pasted bundle.js, since it's not minimized I suspect you didn't run webpack with this flag --mode production. So no removal.

VM2 Usage with Webpack

I've been having trouble using webpack with a typescript project that uses vm2.webpack --config webpack.config.js gives the following error:
ERROR in index.js from Terser
Invalid function parameter [webpack://./node_modules/source-map-loader/dist/cjs.js!./node_modules/vm2/lib/main.js:1226,1][index.js:1262,21]
This is the minimal repro I've been testing with:
import { VM } from 'vm2';
export async function run(): Promise<void> {
new VM();
}
By using the optimization: { minimize: false } } option in my webpack.config.js I was able to find the source of the error. In the vm2 package source code this block exists:
const HOST = {
...,
require,
...
}
which gets webpacked as:
const HOST = {
...,
__webpack_require__(952),
...
}
This clearly fails. I'm not sure what I else I can do here, is there a config somewhere I can change to
My webpack.config.js:
const path = require('path');
module.exports = {
target: 'node',
entry: './vm2index.ts',
output: {
filename: 'index.js',
path: path.resolve(__dirname, 'dist'),
libraryTarget: 'commonjs',
},
// optimization: {
// minimize: false,
// },
resolve: {
extensions: ['.ts', '.tsx', '.js', '.jsx'],
},
devtool: 'source-map',
mode: 'production',
// Add the loader for .ts files.
module: {
rules: [
{
test: /\.tsx?$/,
loader: 'awesome-typescript-loader',
exclude: /node_modules/,
},
{
enforce: 'pre',
test: /\.js$/,
loader: 'source-map-loader',
},
],
},
stats: {
warningsFilter: [
"Module not found: Error: Can't resolve 'encoding'",
"Cannot find SourceMap 'typescript.js.map'",
],
}
};

React native web storybook react-native-vector-icons problem icon

I'm developing a react native component on storybook, which uses react-native-paper and react-native-vector-icons.
The problem is that I can't see the icons, I tried to follow the guide on react-native-vector-icons, this: webpack
Below is the webpack, but I didn't quite understand how to use the second part of the code suggested in the guide, where and how I should use it.
Can anyone help me out?
webpack:
const path = require('path')
const HTMLWebpackPlugin = require('html-webpack-plugin')
const HTMLWebpackPluginConfig = new HTMLWebpackPlugin({
template: path.resolve(__dirname, './public/index.html'),
filename: 'index.html',
inject: 'body',
})
module.exports = {
entry: path.join(__dirname, 'index.web.js'),
output: {
filename: 'bundle.js',
path: path.join(__dirname, '/build'),
},
resolve: {
alias: {
'react-native$': 'react-native-web',
'#storybook/react-native': '#storybook/react',
'styled-components/native': 'styled-components',
},
},
module: {
rules: [
{
test: /\.(js|jsx|ts|tsx)$/,
exclude: /node_modules[/\\](?!react-native-vector-icons)/,
use: {
loader: 'babel-loader',
options: {
// Disable reading babel configuration
babelrc: false,
configFile: false,
presets: [
'#babel/preset-env',
'#babel/preset-react',
'#babel/preset-flow',
'#babel/preset-typescript',
{
plugins: ['#babel/plugin-proposal-class-properties', '#babel/plugin-proposal-object-rest-spread'],
},
],
},
},
},
{
test: /\.(jpg|png|woff|woff2|eot|ttf|svg)$/,
loader: 'file-loader',
},
{
test: /\.ttf$/,
loader: 'url-loader', // or directly file-loader
include: path.resolve(__dirname, 'node_modules/react-native-vector-icons'),
},
],
},
plugins: [HTMLWebpackPluginConfig],
devServer: {
historyApiFallback: true,
contentBase: './',
hot: true,
},
}

The reason for your problem could be that your webpack.config.js is located in the folder .storybook.
So you have to change the path for loading the react-native-vector-icons and add ../ before node_modules, because of the folder structure.
...
{
test: /\.ttf$/,
loader: 'url-loader', // or directly file-loader
// add .. to the path for node_modules
include: path.resolve(__dirname, '../node_modules/react-native-vector-icons'),
},
...
An similar issue has been described and solved here: React Native Vector Icons don't load on react-native-web storybook

Import SCSS as string

I'm trying to import some SCSS into a Javascript file with mixed results. I've found that this works:
style.styleString.scss
body {
background: #556;
}
.test {
&__child {
color: red;
}
}
index.js
import "./index.style"; // making sure that nothing we do breaks normal SCSS importing
const css = require("!!raw-loader!sass-loader!./style.stringStyle.scss").default;
console.log(css);
index.style.scss is correctly compiled to a file and style.stringStyle.scss is correctly printed in the console.
What I'd like to do is move this loader pipeline into my webpack config. This is what I have at the moment:
import MiniCssExtractPlugin from "mini-css-extract-plugin";
import path from "path";
const config = {
mode: "development",
entry: {
"app": "./src/index.js",
},
output: {
path: path.resolve(process.cwd(), "dist"),
filename: "[name].js",
},
module: {
rules: [
{
test: /\.stringStyle.scss$/i,
use: [
"raw-loader",
"sass-loader",
],
},
{
test: /\.scss$/i,
use: [
{
loader: MiniCssExtractPlugin.loader,
},
{
loader:"css-loader",
options: {
url: false,
},
},
"sass-loader",
],
},
],
},
resolve: {
extensions: [".js", ".scss", ".css"],
},
devtool: "source-map",
plugins: [
new MiniCssExtractPlugin({
filename: "[name].css",
}),
],
};
export default config;
index.js
import "./index.style"; // making sure that nothing we do breaks normal SCSS importing
const css = require("./style.stringStyle.scss").default;
console.log(css);
With this configuration, an empty string is printed to the console (index.style.scss still correctly renders to a file).
What am I doing wrong here? I was sort of under the impression that using the inline ! syntax in imports works just like lining up loaders in the config file, but I'm clearly missing something.
Is it possible to setup loading SCSS files as CSS strings in my Webpack config?

Both SCSS tracking rules are getting applied to style.stringStyle.scss. Adding a negative look-behind to the normal import rule's test regex will make sure only the correct rule is selected:
import MiniCssExtractPlugin from "mini-css-extract-plugin";
import path from "path";
const config = {
mode: "development",
entry: {
"app": "./src/index.js",
},
output: {
path: path.resolve(process.cwd(), "dist"),
filename: "[name].js",
},
module: {
rules: [
{
test: /\.stringStyle.scss$/i,
use: [
"raw-loader",
"sass-loader",
],
},
{
test: /(?<!\.stringStyle)\.scss$/i,
use: [
{
loader: MiniCssExtractPlugin.loader,
},
{
loader:"css-loader",
options: {
url: false,
},
},
"sass-loader",
],
},
],
},
resolve: {
extensions: [".js", ".scss", ".css"],
},
devtool: "source-map",
plugins: [
new MiniCssExtractPlugin({
filename: "[name].css",
}),
],
};
export default config;

Webpack style-loader / css-loader: url() path resolution not working

There are a few SO posts about style-loader and css-loader, but despite this I have not been able to find a solution to my problem.
In short summary, when I #import css files in other css files, and the imported css contains url()s with relative paths, the paths are not resolved correctly.
Basically, the error message shows that Webpack ends up thinking the url() paths in the imported css are relative to src (main entry point), rather than being relative to the css file it it is imported into:
// css-one.scss
#import "./assets/open-iconic-master/font/css/open-iconic-bootstrap.css";
// open-iconic-bootstrap.css
#font-face {
src: url('../fonts/open-iconic.eot');
}
Error:
ERROR in ./src/main.scss
(./node_modules/css-loader??ref--5-1!./node_modules/postcss-loader/src??ref--5-2!./node_modules/sass-loader/lib/loader.js??ref--5-3!./src/main.scss)
Module not found: Error: Can't resolve '../fonts/open-iconic.eot' in
'C:\Users\...\src'
# ./src/main.scss
(./node_modules/css-loader??ref--5-1!./node_modules/postcss-loader/src??ref--5-2!./node_modules/sass-loader/lib/loader.js??ref--5-3!./src/main.scss) 7:106-141 7:172-207 # ./src/main.scss # ./src/index.js
What I Have Tried:
I have tried to use the convertToAbsoluteUrls flag in style-loader
I have tried to turn off all source maps (mentioned in style-loader docs)
My Webpack Config File (loaders are at the bottom):
const path = require('path');
const webpack = require('webpack'); // for webpack built-in plugins
const UglifyJSPlugin = require('uglifyjs-webpack-plugin');
const CleanWebpackPlugin = require('clean-webpack-plugin');
const HtmlWebpackPlugin = require('html-webpack-plugin');
const MiniCssExtractPlugin = require('mini-css-extract-plugin');
const CopyWebpackPlugin = require('copy-webpack-plugin');
// const WriteFilePlugin = require('write-file-webpack-plugin');
// const ManifestPlugin = require('webpack-manifest-plugin');
// const InlineManifestWebpackPlugin = require('inline-manifest-webpack-plugin');
// const BundleAnalyzerPlugin = require('webpack-bundle-analyzer').BundleAnalyzerPlugin;
const PATHS = {
// when using __dirname, resolve and join gives same result,
// because __dirname is absolute path to directory of this file.
// OK to use no slashes,
// both resolve and join adds platform-specific separators by default
src: path.resolve(__dirname, 'src'),
dist: path.resolve(__dirname, 'dist'),
build: path.resolve(__dirname, 'build'),
test: path.resolve(__dirname, 'test')
};
const NAMES = {
// JS FILES
index: 'index',
print: 'print',
// Chrome Extension Development
popup: 'popup',
options: 'options',
background: 'background',
contentScript: 'contentScript',
// FOLDERS
assets: 'assets',
utilities: 'utilities',
images: 'images',
fonts: 'fonts',
include: 'include'
};
const FILE_PATHS = {
// JS
indexJs: `${path.join(PATHS.src, NAMES.index)}.js`,
printJs: `${path.join(PATHS.src, NAMES.print)}.js`,
// Chrome Extension Development
popupJs: `${path.join(PATHS.src, NAMES.popup)}.js`,
optionsJs: `${path.join(PATHS.src, NAMES.options)}.js`,
backgroundJs: `${path.join(PATHS.src, NAMES.background)}.js`,
contentScriptJs: `${path.join(
PATHS.src,
NAMES.include,
NAMES.contentScript
)}.js`,
// HTML
indexHtml: `${path.join(PATHS.src, NAMES.index)}.html`,
printHtml: `${path.join(PATHS.src, NAMES.print)}.html`,
// Chrome Extension Development
popupHtml: `${path.join(PATHS.src, NAMES.popup)}.html`,
optionsHtml: `${path.join(PATHS.src, NAMES.options)}.html`,
backgroundHtml: `${path.join(PATHS.src, NAMES.background)}.html`
};
// Third-party (vendor) libraries to include
// const VENDORS = ['react', 'bootstrap', 'lodash', 'jQuery']; // Relative paths to node_modules
// Note: These are relative
const ASSETS = {
images: path.join(NAMES.assets, NAMES.images),
fonts: path.join(NAMES.assets, NAMES.fonts)
};
// CleanWebpackPlugin config
const pathsToClean = [PATHS.dist, PATHS.build];
const cleanOptions = {
root: __dirname,
exclude: ['shared.js'],
verbose: true,
dry: false
};
// CopyWebpackPlugin config
const copyPattern = [
// {
// from: NAMES.assets,
// to: NAMES.assets
// },
// {
// from: path.join(NAMES.include, 'contentScript.css')
// },
// {
// from: 'manifest.json',
// transform(content, copyPath) {
// // generates the manifest file using the package.json informations
// return Buffer.from(
// JSON.stringify({
// ...JSON.parse(content.toString())
// // description: env.npm_package_description,
// // version: env.npm_package_version
// })
// );
// }
// }
];
const copyOptions = {
// ignore: ['*.js'],
context: PATHS.src
};
module.exports = (env = {}) => {
// webpack injects env variable, into webpack config.
// perfect to check for production.
// remember to specify --env.production in command
// (if in production mode).
const isProduction = env.production === true;
return {
entry: {
index: FILE_PATHS.indexJs
// Chrome Extension Development
// popup: FILE_PATHS.popupJs,
// contentScript: FILE_PATHS.contentScriptJs
// options: FILE_PATHS.optionsJs,
// background: FILE_PATHS.backgroundJs,
// vendor: VENDORS
},
mode: isProduction ? 'production' : 'development',
devtool: isProduction ? 'source-map' : 'inline-source-map',
optimization: {
splitChunks: {
chunks: 'all'
}
},
output: {
filename: isProduction ? '[name].[chunkhash:8].js' : '[name].js',
// chunkFilename determine name of non-entry chunk files,
// for example dynamic imports in the app
chunkFilename: isProduction ? '[name].[chunkhash:8].js' : '[name].js',
path: PATHS.dist
},
plugins: [
// new webpack.SourceMapDevToolPlugin({
// filename: '[file].map',
// exclude: ['vendor', 'runtime']
// }),
new webpack.DefinePlugin({
// specifies environment variable for dependencies.
// does not apply to browser runtime environment
// (process.env is provisioned by Node)
'process.env.NODE_ENV': isProduction ?
JSON.stringify('production') :
JSON.stringify('development')
}),
// new BundleAnalyzerPlugin(),
new CleanWebpackPlugin(pathsToClean, cleanOptions),
new MiniCssExtractPlugin({
// Options similar to the same options in webpackOptions.output
// both options are optional
// does not work with Hot Module Replacement (HMR)
// allows HMR in development (will only use this plugin in production)
filename: isProduction ? '[name].[contenthash].css' : '[name].css',
chunkFilename: isProduction ? '[id].[contenthash].css' : '[id].css'
}),
new webpack.HashedModuleIdsPlugin(),
isProduction ?
new UglifyJSPlugin({
cache: true,
parallel: true,
sourceMap: true // set to true if you want JS source maps
}) :
() => {},
new CopyWebpackPlugin(copyPattern, copyOptions),
// new WriteFilePlugin(),
new HtmlWebpackPlugin({
template: FILE_PATHS.indexHtml,
filename: `${NAMES.index}.html`
})
// new HtmlWebpackPlugin({
// template: FILE_PATHS.popupHtml,
// filename: `${NAMES.popup}.html`,
// excludeChunks: [NAMES.contentScript]
// In dev mode, chunks excluded vendor chunk (which holds CSS).
// Above check fixes it.
// }),
// new HtmlWebpackPlugin({
// filename: `${NAMES.contentScript}.html`,
// excludeChunks: [NAMES.popup, 'runtime'] // Runtime only needed in one HTML
// }),
// new HtmlWebpackPlugin({
// template: FILE_PATHS.optionsHtml,
// filename: `${NAMES.options}.html`,
// chunks: isProduction ? [NAMES.options] : ''
// }),
// new HtmlWebpackPlugin({
// template: FILE_PATHS.backgroundHtml,
// filename: `${NAMES.background}.html`,
// chunks: isProduction ? [NAMES.background] : ''
// }),
// no need for CSS minimization here <-- Done by PostCSS (cssnano)
// new InlineManifestWebpackPlugin(),
// new ManifestPlugin({fileName: 'webpack-manifest.json'}),
],
module: {
rules: [{
test: /\.js$/,
exclude: /(node_modules|bower_components)/,
use: {
loader: 'babel-loader',
options: {
presets: ['#babel/preset-env']
}
}
},
{
test: /\.s?[ac]ss$/,
exclude: /node_modules/,
use: [
isProduction ?
MiniCssExtractPlugin.loader :
{
// creates style nodes from JS strings
loader: 'style-loader',
options: {
sourceMap: true,
convertToAbsoluteUrls: true
}
},
{
// CSS to CommonJS (resolves CSS imports into exported CSS strings)
loader: 'css-loader',
options: {
sourceMap: true,
importLoaders: 2
}
},
{
loader: 'postcss-loader',
options: {
config: {
ctx: {
cssnext: {},
cssnano: {},
autoprefixer: {}
}
},
sourceMap: true
}
},
{
// compiles Sass to CSS
loader: 'sass-loader',
options: {
sourceMap: true
}
}
]
},
{
test: /\.(png|svg|jpg|gif)$/,
use: [{
loader: 'file-loader',
options: {
name: '[name].[hash:4].[ext]',
outputPath: ASSETS.images
}
}]
},
{
test: /\.(woff|woff2|eot|ttf|otf)$/,
use: [{
loader: 'file-loader',
options: {
name: '[name].[hash:4].[ext]',
outputPath: ASSETS.fonts
}
}]
},
{
test: /\.(csv|tsv)$/,
use: ['csv-loader']
},
{
test: /\.xml$/,
use: ['xml-loader']
},
{
test: /\.(html)$/,
use: {
loader: 'html-loader',
options: {
interpolate: 'require',
minimize: true
}
}
}
// {
// test: /\.tsx?$/,
// exclude: /(node_modules|bower_components)/,
// use: 'ts-loader'
// }
]
},
devServer: {
// contentBase: path.join(__dirname, 'dist'),
contentBase: PATHS.dist,
compress: false,
port: 8080,
open: false
}
};
};

it took me around 5 days of work to understand how this webpack mess works. I have to be honest I can say that this is one of those things that I really do not understand why they are "defacto" tools of the moment. I can't understand how difficult it can be just to make the config files work as it should, in gulp took me 1 hour to do the same.
My problem was that all the url() rules (including fonts and images) were being loaded by css-loader as [object Module], and they where exported by file-loader but never loaded, so if I added ?url=false to the css-loader it never copied the files and export them. I have to say this was a totally PITA, but I got it working, and I hope it works for somebody else in the world, this was made with webpack 4.
const webpack = require("webpack");
const HtmlWebpackPlugin = require('html-webpack-plugin');
const MiniCssExtractPlugin = require("mini-css-extract-plugin");
const ImageminPlugin = require('imagemin-webpack-plugin').default;
const CopyPlugin = require('copy-webpack-plugin');
module.exports = {
entry: "./src/index.js",
mode: "development",
module: {
rules: [
{
test: /\.(js|jsx)$/,
exclude: /(node_modules|bower_components)/,
loader: "babel-loader",
options: { presets: ["#babel/env"] }
},
{
test: /\.(gif|png|jpe?g|svg)$/i,
use: [
{
loader: 'image-webpack-loader',
options: {
mozjpeg: {
progressive: true,
quality: 65
},
optipng: {
enabled: false,
},
pngquant: {
quality: [0.65, 0.90],
speed: 4
},
gifsicle: {
interlaced: false,
},
webp: {
quality: 75
},
}
},
{
loader: 'file-loader',
options:{
name: '[name].[ext]',
outputPath: 'images/',
publicPath: 'images/'
}
},
'url-loader?limit=100000'
],
},
{
test: /\.(woff(2)?|ttf|eot)(\?v=\d+\.\d+\.\d+)?$/,
use: [
{
loader: 'file-loader',
options: {
name: '[name].[ext]',
outputPath: 'fonts/'
}
}
]
},
{
test: /\.s[ac]ss$/i,
use: [
MiniCssExtractPlugin.loader,
{ loader: 'css-loader?url=false'},
{ loader: 'sass-loader', options: { sourceMap: true } }
],
},
]
},
resolve: { extensions: ["*", ".js", ".jsx"] },
output: {
path: path.resolve(__dirname, "dist/"),
publicPath: "",
filename: "bundle.js"
},
devServer: {
contentBase: path.join(__dirname, "dist/"),
port: 3000,
publicPath: "http://localhost:3000/dist/",
hotOnly: true
},
plugins: [ new MiniCssExtractPlugin(),
new CopyPlugin([{ from: 'src/images/', to: 'images/' }]),
new CopyPlugin([{ from: 'src/fonts/', to: 'fonts/' }]),
new ImageminPlugin({ test: /\.(jpe?g|png|gif|svg)$/i }),
new HtmlWebpackPlugin({
hash: true,
template: './src/index.html',
filename: './index.html' //relative to root of the application
}),
]
};

You can turn off processing of url() rules, btw. I have no idea, why this is a default behavior.
{
loader: 'css-loader',
options: {
...
url: false,
}
},

I was able to solve the problem myself. In case it could help others in the future, please find the solution below.
First of all, if you are using both postcss-loader with the postcss-import plugin, AND css-loader, turn off / delete the postcss-import plugin. You do not need more than one tool that resolves #import rules. This is not really a problem if the order of loaders is correct, but you might as well remove it.
In the sass-loader docs, you can read the following:
Since Sass/libsass does not provide url rewriting, all linked assets
must be relative to the output.
If you're just generating CSS without passing it to the css-loader, it must be relative to your web root.
If you pass the generated CSS on to the css-loader, all urls must be relative to the entry-file (e.g. main.scss).
More likely you will be disrupted by this second issue. It is natural to expect relative references to be resolved against the .scss file in which they are specified (like in regular .css files). Thankfully there are two solutions to this problem:
Add the missing url rewriting using the resolve-url-loader. Place it before the sass-loader in the loader chain.
Library authors usually provide a variable to modify the asset path. bootstrap-sass for example has an $icon-font-path. Check out this working bootstrap example.
I decided to follow bullet two, and add in resolve-url-loader above sass-loader in the Webpack config. It now works as expected.
My final Webpack config (for now) looks like this:
{
test: /\.s?[ac]ss$/,
exclude: /node_modules/,
use: [
isProduction
? MiniCssExtractPlugin.loader
: {
// creates style nodes from JS strings
loader: 'style-loader',
options: {
sourceMap: true,
// convertToAbsoluteUrls: true
}
},
{
// CSS to CommonJS (resolves CSS imports into exported CSS strings)
loader: 'css-loader',
options: {
sourceMap: true,
importLoaders: 2
// url: false,
// import: false
}
},
{
loader: 'postcss-loader',
options: {
config: {
ctx: {
cssnext: {},
cssnano: {},
autoprefixer: {}
}
},
sourceMap: true
}
},
{
loader: 'resolve-url-loader',
options: {
attempts: 1,
sourceMap: true
}
},
{
// compiles Sass to CSS
loader: 'sass-loader',
options: { sourceMap: true }
}
]
},
Side Notes
I noticed that source map paths under "no domain" in Chrome's debugger are repeated. If anyone figures out why, please do share
Remember to include the below side effects in package.json, so tree shaking, which happens in production mode, does not delete the extracted css
"sideEffects": [
".css",
".scss"
],

In webpack 5, you should refrain from using raw-loader and file-loader, instead use asset/source and asset/resource.
{
test: /\.txt$/,
type: 'asset/source',
},
{
test: /\.png$/,
type: 'asset/resource',
},
You can read more about assets on: https://webpack.js.org/guides/asset-modules/. It's described how for Webpack 4 and earlier you should use file-loader, and for Webpack5 and later you should use asset modules.

If anyone is struggling with this using Webpack 5 and is trying to upgrade from css-loader 5 to css-loader 6, you might need to check this issue where the poster has a similar problem to the OP:
With css-loader 5.2.7 the images in the input stylus were embedded as data-
URL in the output CSS. With css-loader 6, the images are instead moved
to the output directory.
See Notes here for how to upgrade to css-loader 6 - the salient points are:
using ~ is deprecated when the esModules option is enabled ... and can
be removed from your code
and
file-loader and url-loader are deprecated, please migrate on asset
modules, since v6 css-loader is generating new URL(...) syntax, it
enables by default built-in assets modules, i.e. type: 'asset' for all
url()
I've therefore done the following:
removed any '~' in my .scss files
i.e.
$font-path: "~/src/fonts" !default;
becomes
$font-path: "/src/fonts" !default;
I've also removed the 'file-loader' module completely.
All NPM packages are now up to date and URLs in CSS are working correctly.

IE is not compatible with new URL()

My issue was that webpack 5 changed everything with "Asset modules" apparently and broke file-loader.
Official docs explain it well: https://webpack.js.org/guides/asset-modules/
TL;DR you can fix it by adding type: 'javascript/auto' to the rule/loader
{
test: /\.(eot|ttf|woff2?)($|\?)/i,
loader: 'file-loader',
options: {
name: '[name]-[sha1:hash:hex:10].[ext]',
esModule: false,
},
type: 'javascript/auto'
},