Related
I've made some edits which are listed below.
I am working with a combination of React (18.2.0), Typescript (4.8.4), and Webpack (5.75.0). I am attempting to add some styling to my application, and am trying to use CSS modules. I have tried a few Webpack configurations, and none of them are causing Webpack to use the correct loader. I have tried a few other variants of loaders (as seen in the commented out sections), and none of them are working.
I am using an approach similar to this answer to import the stylesheets (declaring a src/Globals.d.ts, setting the typescript-plugin-css-modules compiler plugin for tsc, and importing as import * as styles from './styles.module.css')
Stylesheet import
import * as styles from './ResultCount.module.css'
export const ResultCount = () => {
const orders = useSelector((state: ReducedState) => state.all.orders)
console.log('result count style name', styles.results) // always undefined
return <p className={styles.results}>
src/Globals.d.ts
declare module '*.module.css'
This is the error that I get, regardless of the loader configuration that I use
cached modules 1.59 MiB (javascript) 27.4 KiB (runtime) [cached] 131 modules
./src/components/Order/styles.module.css 96 bytes [built] [1 error]
ERROR in ./src/components/Order/styles.module.css 1:0
Module parse failed: Unexpected token (1:0)
You may need an appropriate loader to handle this file type, currently no loaders are configured to process this file. See https://webpack.js.org/concepts#loaders
> .order {
...
Would someone be able to tell me what I am doing wrong in my webpack.config.ts file?
module: {
rules: [
{
test: /\.tsx?$/,
loader: 'ts-loader',
options: {
transpileOnly: true
},
exclude: /dist/
},
{
test: /\.css$/,
use: [
"style-loader",
{
loader: "css-loader",
options: {
modules: true,
importLoaders: 1,
localIdentName: "[name]_[local]_[hash:base64]",
sourceMap: true,
minimize: true
}
}
]
},
// {
// test: /\.css$/,
// include: path.join(__dirname, 'src/components'),
// loader: 'css-loader',
// //use: ['style-loader', 'css-loader']
// // use: [
// // 'style-loader',
// // {
// // loader: 'typings-for-css-modules-loader',
// // options: {
// // modules: true,
// // namedExport: true
// // },
// // },
// // 'css-loader',
// // ],
// },
]
},
Edit
I've found out that webpack serve must be restarted for these sorts of changes to take affect (even with reloading turned on). The new issue is: although Webpack successfully builds, but any import of the classes in the .ts files returns an undefined. So none of the styles are applied. I've update the title to reflect the new issue.
What's strange is that my language server (tsserver) can auto complete the classes defined in the .css file from import * as styles from './styles.module.css', but if I console.log() it before I return my TSX, I always see an undefined value. I've confirmed that the mangled CSS modules names are in the final rendered page by finding the inline styles in the browser inspector. I've also tried declaring a styles.module.css.d.ts file (even though I shouldn't need to due to the Typescript plugin) just in case, but that still did not fix the issue. I've also tried (from this answer) to rename from styles.module.css to <component name here>.module.css but that also did not work.
Does anyone know what could be causing this?
import * as styles from "module-path"; is semantically different to import styles from "module-path";. Basically don't assume these non-javascript made-up modules follow any advanced module rules and always default import them.
In CRA React App, I have a common style guide in SCSS which is imported in module level scss files using #use, using dart SASS as well.
I have changed the references from #import to #use and was expecting Webpack will handle as common code, will create a separate chunk
Problem
How to make one common chunk for a common style guide.
Screenshots
This can be achieved by Extract Text Plugin, which...
Extracts text from a bundle, or bundles, into a separate file. For more check this.
const path = require("path");
const MiniCssExtractPlugin = require("mini-css-extract-plugin");
module.exports = {
entry: {
foo: path.resolve(__dirname, "src/foo"),
bar: path.resolve(__dirname, "src/bar"),
},
optimization: {
splitChunks: {
cacheGroups: {
fooStyles: {
type: "css/mini-extract",
name: "styles_foo",
chunks: (chunk) => {
return chunk.name === "foo";
},
enforce: true,
},
barStyles: {
type: "css/mini-extract",
name: "styles_bar",
chunks: (chunk) => {
return chunk.name === "bar";
},
enforce: true,
},
},
},
},
plugins: [
new MiniCssExtractPlugin({
filename: "[name].css",
}),
],
module: {
rules: [
{
test: /\.css$/,
use: [MiniCssExtractPlugin.loader, "css-loader"],
},
],
},
}
Though, I'm not sure if you're looking for the above one or another plug-in called CommonsChunkPlugin, which acts similar.
The CommonsChunkPlugin is an opt-in feature that creates a separate file (known as a chunk), consisting of common modules shared between multiple entry points.
Example:
new webpack.optimize.CommonsChunkPlugin({
name: 'app',
// or
names: ['app', 'subPageA'],
// the name or list of names must match the name or names
// of the entry points that create the async chunks
children: true, // use all children of the chunk
async: true,
minChunks: 3, // 3 children must share the module before it's separated
})
I'm seeing src in your images, which tells me that those screen captures you took is in development, not production.
In development webpack should use style-loader and directly load all styles and inject it into the DOM using style tags to speed up development. So seeing multiple files is normal in development.
In production webpack should use something like mini-css-extract-plugin and compile all your sass to a single css file.
The only way to get multiple css files in webpack for production is to create multiple entries for each file.
I am trying to import css to my specific component of react app.
webpack config:
{
test: /\.css$/,
loader: ExtractTextPlugin.extract({
use: 'css-loader',
}),
}
but css is not applied.
I also included the main css inside index.html. Is it the reason why I cannot apply another css file?
<link rel="stylesheet" href="../style/style.css">
Can you suggest me what's missing?
It depends on the webpack version you're using. For example, if you're using Webpack 4, then your development config would be:
{
test: /\.s?css$/, // test for scss or css files
use: [
'style-loader', // try to use style-loader or...
{
loader: 'css-loader', // try to use css-loader
options: {
sourceMap: true, // allow source maps (allows css debugging)
modules: true, // allow css module imports
camelCase: true, // allow camel case imports
localIdentName: '[local]___[hash:base64:5]', // set imported classNames with a original className and a hashed string in the DOM, for example: "exampleClassName__2fMQK"
},
},
],
}
example.css (must use camel case instead of snake case)
.exampleClassName {
text-align: center;
}
example.js
import React from 'react';
import { exampleClassName } from './example.css';
export default () => (
<h1 className={exampleClassName}>I am centered!</h1>
)
For production, you'll want to use OptimizeCSSAssetsPlugin and MiniCssExtractPlugin :
minimizer: [
new OptimizeCSSAssetsPlugin({
cssProcessorOptions: {
map: {
inline: false,
annotation: true
}
}
}),
],
{
plugins: [
new MiniCssExtractPlugin({
filename: `css/[name].[contenthash:8].css`,
chunkFilename: `[id].[contenthash:8].css`,
}),
]
}
When you run webpack to build your application for production, it'll compile the css and (when the webpack config is set up properly) will generate an index.html that automatically adds a link to the compiled stylesheet.
Webpack is a steep learning curve and there's a lot of missing options from the above examples, so if you're just trying to get it up and running, then I have a Webpack-React-Boilerplate that has (s)css modules imports and a lot more already configured for you. I've included notes within the webpack config files to help assist as to what each option is doing.
Otherwise, if you're trying to learn older versions of webpack, then you can eject the create-react-app and reverse engineer/look at their extensive webpack notes.
Introduction
I have already setup bundling for my Javascript files with webpack in my project. Now I am in the process of adding CSS files to the webpack configuration. So far, I have been including the CSS files manually in the HTML header by adding <link> elements for every CSS file I depend on (e.g. bootstrap, my own css, etc.). Obviously this is not very elegant and using webpack would be much better, so I would like to replace the link elements and bundle them via webpack.
This should be easy, everything is pretty much documented in the webpack documentation. After reading the documentation and experimenting a bit with webpack I have arrived at the configuration below which already works.
Problem
The problem with my current setup is that I would like to have proper source map support and that does not seem to work. By proper, I mean that I expect that when I run a development build with webpack and I inspect some element in Chrome DevTools, that I will see from which file and which line in the file a certain CSS class originated and that I can click on the CSS rules and the browser jumps to that file.
I do not want to have inline styles in the head element, because then the browser will show something like .foobar { <style>..</style>, rather then .foobar { app.css:154.
With my current setup I have all CSS files combined (but not minified) into one app.css file. This means that if I inspect a bootstrap class such as .btn then it appears as .btn { app.css:3003. However, what I want to achieve is that the browser shows it as .btn { bootstrap.css:3003.
So now I am trying to understand how webpack and the different plugins such as css-loader and min-css-extract-plugin apply CSS source maps, and how I can configure them to achieve a proper debugging experience.
I am not sure how relevant this is, but when I navigate in DevTools under Sources to webpack://./bootstrap/dist/css/bootstrap.css I see that it only contains a single line:
// extracted by mini-css-extract-plugin.
Webpack Setup
index.js:
window.jQuery = require('jquery/dist/jquery');
require('bootstrap/dist/css/bootstrap.css');
require('bootstrap/dist/js/bootstrap');
/* other dependencies */
webpack.config.js:
const devMode = process.env.NODE_ENV !== 'production';
const MiniCssExtractPlugin = require('mini-css-extract-plugin');
module: {
rules: [
{ /* Javascript rules excluded */ },
{
test: /\.css$/,
use: [
{
loader: MiniCssExtractPlugin.loader
},
{
loader: 'css-loader',
options: {
sourceMap: true
}
}
]
},
{
test: /\.(png|svg|jpg|gif)$/,
use: [
'file-loader'
]
},
{
test: /\.(woff|woff2|eot|ttf|otf)$/,
use: [
'file-loader'
]
}
plugins: [
new UglifyJSPlugin (),
new HtmlWebpackPlugin({
template: 'app/index.tpl.html'
}),
new MiniCssExtractPlugin({ filename: devMode ?
'[name].css' :
'[name].[hash].css'
})
],
Conclusion
It seems I just passed the rubber duck test. While I was writing this I arrived at a solution. I will still publish the question, maybe it can help others.
The problem was that I was also using the mini-css-extract-plugin for development and not just for production. I thought that I needed to do that, because when at first I was using the style-loaded I would get styles included in the header and the browser would show me all styles as .foobar { <style>..</style>.
However, the actual problem seemed to be, that I was not using devtools. So the solution was to add devtool: devMode ? 'cheap-module-eval-source-map' : 'source-map', to the webpack configuration to conditionally use the style-loader plugin during development builds and mini-css-extract-plugin during production builds.
webpack.config.js
{
test: /\.css$/,
use: [
{
- loader: MiniCssExtractPlugin.loader,
+ loader: devMode ? 'style-loader' : MiniCssExtractPlugin.loader,
},
{
loader: 'css-loader',
options: {
sourceMap: true
}
}
]
},
/* ... */
+ devtool: devMode ? 'cheap-module-eval-source-map' : 'source-map',
import '../../../../node_modules/react-responsive-carousel/lib/styles/carousel.min.css';
I have imported the above in my react app, but the classes are getting hashed since i am using css modules.. How can i import that css library in my component?
'use strict';
const autoprefixer = require('autoprefixer');
const path = require('path');
const webpack = require('webpack');
const HtmlWebpackPlugin = require('html-webpack-plugin');
const CaseSensitivePathsPlugin = require('case-sensitive-paths-webpack-plugin');
const InterpolateHtmlPlugin = require('react-dev-utils/InterpolateHtmlPlugin');
const WatchMissingNodeModulesPlugin = require('react-dev-utils/WatchMissingNodeModulesPlugin');
const eslintFormatter = require('react-dev-utils/eslintFormatter');
const ModuleScopePlugin = require('react-dev-utils/ModuleScopePlugin');
const getClientEnvironment = require('./env');
const paths = require('./paths');
// Webpack uses `publicPath` to determine where the app is being served from.
// In development, we always serve from the root. This makes config easier.
const publicPath = '/';
// `publicUrl` is just like `publicPath`, but we will provide it to our app
// as %PUBLIC_URL% in `index.html` and `process.env.PUBLIC_URL` in JavaScript.
// Omit trailing slash as %PUBLIC_PATH%/xyz looks better than %PUBLIC_PATH%xyz.
const publicUrl = '';
// Get environment variables to inject into our app.
const env = getClientEnvironment(publicUrl);
// This is the development configuration.
// It is focused on developer experience and fast rebuilds.
// The production configuration is different and lives in a separate file.
module.exports = {
// You may want 'eval' instead if you prefer to see the compiled output in DevTools.
// See the discussion in https://github.com/facebookincubator/create-react-app/issues/343.
devtool: 'cheap-module-source-map',
// These are the "entry points" to our application.
// This means they will be the "root" imports that are included in JS bundle.
// The first two entry points enable "hot" CSS and auto-refreshes for JS.
entry: [
// We ship a few polyfills by default:
require.resolve('./polyfills'),
// Include an alternative client for WebpackDevServer. A client's job is to
// connect to WebpackDevServer by a socket and get notified about changes.
// When you save a file, the client will either apply hot updates (in case
// of CSS changes), or refresh the page (in case of JS changes). When you
// make a syntax error, this client will display a syntax error overlay.
// Note: instead of the default WebpackDevServer client, we use a custom one
// to bring better experience for Create React App users. You can replace
// the line below with these two lines if you prefer the stock client:
// require.resolve('webpack-dev-server/client') + '?/',
// require.resolve('webpack/hot/dev-server'),
require.resolve('react-dev-utils/webpackHotDevClient'),
// Finally, this is your app's code:
paths.appIndexJs,
// We include the app code last so that if there is a runtime error during
// initialization, it doesn't blow up the WebpackDevServer client, and
// changing JS code would still trigger a refresh.
],
output: {
// Add /* filename */ comments to generated require()s in the output.
pathinfo: true,
// This does not produce a real file. It's just the virtual path that is
// served by WebpackDevServer in development. This is the JS bundle
// containing code from all our entry points, and the Webpack runtime.
filename: 'static/js/bundle.js',
// There are also additional JS chunk files if you use code splitting.
chunkFilename: 'static/js/[name].chunk.js',
// This is the URL that app is served from. We use "/" in development.
publicPath: publicPath,
// Point sourcemap entries to original disk location (format as URL on Windows)
devtoolModuleFilenameTemplate: info =>
path.resolve(info.absoluteResourcePath).replace(/\\/g, '/'),
},
resolve: {
// This allows you to set a fallback for where Webpack should look for modules.
// We placed these paths second because we want `node_modules` to "win"
// if there are any conflicts. This matches Node resolution mechanism.
// https://github.com/facebookincubator/create-react-app/issues/253
modules: ['node_modules', paths.appNodeModules].concat(
// It is guaranteed to exist because we tweak it in `env.js`
process.env.NODE_PATH.split(path.delimiter).filter(Boolean)
),
// These are the reasonable defaults supported by the Node ecosystem.
// We also include JSX as a common component filename extension to support
// some tools, although we do not recommend using it, see:
// https://github.com/facebookincubator/create-react-app/issues/290
// `web` extension prefixes have been added for better support
// for React Native Web.
extensions: ['.web.js', '.mjs', '.js', '.json', '.web.jsx', '.jsx'],
alias: {
// Support React Native Web
// https://www.smashingmagazine.com/2016/08/a-glimpse-into-the-future-with-react-native-for-web/
'react-native': 'react-native-web',
},
plugins: [
// Prevents users from importing files from outside of src/ (or node_modules/).
// This often causes confusion because we only process files within src/ with babel.
// To fix this, we prevent you from importing files out of src/ -- if you'd like to,
// please link the files into your node_modules/ and let module-resolution kick in.
// Make sure your source files are compiled, as they will not be processed in any way.
new ModuleScopePlugin(paths.appSrc, [paths.appPackageJson]),
],
},
module: {
strictExportPresence: true,
rules: [
// TODO: Disable require.ensure as it's not a standard language feature.
// We are waiting for https://github.com/facebookincubator/create-react-app/issues/2176.
// { parser: { requireEnsure: false } },
// First, run the linter.
// It's important to do this before Babel processes the JS.
{
test: /\.(js|jsx|mjs)$/,
enforce: 'pre',
use: [
{
options: {
formatter: eslintFormatter,
eslintPath: require.resolve('eslint'),
},
loader: require.resolve('eslint-loader'),
},
],
include: paths.appSrc,
},
{
// "oneOf" will traverse all following loaders until one will
// match the requirements. When no loader matches it will fall
// back to the "file" loader at the end of the loader list.
oneOf: [
// "url" loader works like "file" loader except that it embeds assets
// smaller than specified limit in bytes as data URLs to avoid requests.
// A missing `test` is equivalent to a match.
{
test: [/\.bmp$/, /\.gif$/, /\.jpe?g$/, /\.png$/],
loader: require.resolve('url-loader'),
options: {
limit: 10000,
name: 'static/media/[name].[hash:8].[ext]',
},
},
// Process JS with Babel.
{
test: /\.(js|jsx|mjs)$/,
include: paths.appSrc,
loader: require.resolve('babel-loader'),
options: {
// This is a feature of `babel-loader` for webpack (not Babel itself).
// It enables caching results in ./node_modules/.cache/babel-loader/
// directory for faster rebuilds.
cacheDirectory: true,
},
},
// "postcss" loader applies autoprefixer to our CSS.
// "css" loader resolves paths in CSS and adds assets as dependencies.
// "style" loader turns CSS into JS modules that inject <style> tags.
// In production, we use a plugin to extract that CSS to a file, but
// in development "style" loader enables hot editing of CSS.
{
test: /\.css$/,
use: [
require.resolve('style-loader'),
{
loader: require.resolve('css-loader'),
options: {
importLoaders: 1,
modules: true,
localIdentName: '[name]_[local]_[hash:base64:5]'
},
},
{
loader: require.resolve('postcss-loader'),
options: {
// Necessary for external CSS imports to work
// https://github.com/facebookincubator/create-react-app/issues/2677
ident: 'postcss',
plugins: () => [
require('postcss-flexbugs-fixes'),
autoprefixer({
browsers: [
'>1%',
'last 4 versions',
'Firefox ESR',
'not ie < 9', // React doesn't support IE8 anyway
],
flexbox: 'no-2009',
}),
],
},
},
],
},
// "file" loader makes sure those assets get served by WebpackDevServer.
// When you `import` an asset, you get its (virtual) filename.
// In production, they would get copied to the `build` folder.
// This loader doesn't use a "test" so it will catch all modules
// that fall through the other loaders.
{
// Exclude `js` files to keep "css" loader working as it injects
// its runtime that would otherwise processed through "file" loader.
// Also exclude `html` and `json` extensions so they get processed
// by webpacks internal loaders.
exclude: [/\.(js|jsx|mjs)$/, /\.html$/, /\.json$/],
loader: require.resolve('file-loader'),
options: {
name: 'static/media/[name].[hash:8].[ext]',
},
},
],
},
// ** STOP ** Are you adding a new loader?
// Make sure to add the new loader(s) before the "file" loader.
],
},
plugins: [
// Makes some environment variables available in index.html.
// The public URL is available as %PUBLIC_URL% in index.html, e.g.:
// <link rel="shortcut icon" href="%PUBLIC_URL%/favicon.ico">
// In development, this will be an empty string.
new InterpolateHtmlPlugin(env.raw),
// Generates an `index.html` file with the <script> injected.
new HtmlWebpackPlugin({
inject: true,
template: paths.appHtml,
}),
// Add module names to factory functions so they appear in browser profiler.
new webpack.NamedModulesPlugin(),
// Makes some environment variables available to the JS code, for example:
// if (process.env.NODE_ENV === 'development') { ... }. See `./env.js`.
new webpack.DefinePlugin(env.stringified),
// This is necessary to emit hot updates (currently CSS only):
new webpack.HotModuleReplacementPlugin(),
// Watcher doesn't work well if you mistype casing in a path so we use
// a plugin that prints an error when you attempt to do this.
// See https://github.com/facebookincubator/create-react-app/issues/240
new CaseSensitivePathsPlugin(),
// If you require a missing module and then `npm install` it, you still have
// to restart the development server for Webpack to discover it. This plugin
// makes the discovery automatic so you don't have to restart.
// See https://github.com/facebookincubator/create-react-app/issues/186
new WatchMissingNodeModulesPlugin(paths.appNodeModules),
// Moment.js is an extremely popular library that bundles large locale files
// by default due to how Webpack interprets its code. This is a practical
// solution that requires the user to opt into importing specific locales.
// https://github.com/jmblog/how-to-optimize-momentjs-with-webpack
// You can remove this if you don't use Moment.js:
new webpack.IgnorePlugin(/^\.\/locale$/, /moment$/),
],
// Some libraries import Node modules but don't use them in the browser.
// Tell Webpack to provide empty mocks for them so importing them works.
node: {
dgram: 'empty',
fs: 'empty',
net: 'empty',
tls: 'empty',
child_process: 'empty',
},
// Turn off performance hints during development because we don't do any
// splitting or minification in interest of speed. These warnings become
// cumbersome.
performance: {
hints: false,
},
};
This is my webpack config file. I tried looking around and some people seem use ~ which doesnt work on my app, seems like my app doesnt know what ~ is. Some people seem to use import !style-loader!css-loader etc... but it doesnt work in my app as well.. it looks like my app doesnt know what to do with the !. It will not compile. I have been searching for days and i can't seem to figure it out.
btw i'm new to this webpack react stuff, if you answer something please try to include as much detail as possible so i can understand it. thank you!
I started my app with create-react-app and then did eject on the app to get access to the config files..