I'm trying to compose a webpack bundle from existing js files and use exports from that in both other JS files and occasionally in html script tag. Later add babel to transpile the whole thing to es5, hence commented out section with babel and ts, that btw works fine.
For now I am having a problem with the exports using straight webpack.
Webpack config as as follows:
var path = require('path');
const { updateCommaList } = require('typescript');
module.exports = {
entry: {
'core' : [
'./src/utils.js',
'./src/zdlg.js'
]
},
devtool: 'source-map',
stats: 'verbose',
resolve: {
modules: ['node_modules']
},
resolveLoader: {
extensions: ['.ts', '.tsx'],
mainFields: ['loader', 'main']
},
output: {
filename: '[name].js',
library: "LIB",
libraryTarget: 'var',
path: path.resolve(__dirname, "dist")
},
module: {
}
};
I can bundle files, no errors there. I'm exporting functions using export statement like so:
export function v ...
And in the html file I have
<script src="./core.js"></script>
<script type="module" src="./io.js"></script>
After tinkering for last few days I've figured out couple things.
If I have a single file in the entry section for core object, exports work, in that the LIB variable has property for each exported function and I can call LIB.v() fine.
imports do not work anyway, i.e.
io.js import:
import {v} from './core.js';
Generates an error when loading the page: Uncaught SyntaxError: import not found: v for the line above.
Adding second file to entry causes webpack to override exports from the 1st file. The reason I didn't see any exports initially was that zdlg.js wasn't exporting anything, and LIB had no exports. If zdlg.js exports any functions they are the only ones that show up on the LIB.
So, in the end, I can export functions from a single file, but I thought the whole purpose of the webpack was to allow to compose modules from multiple files.
I'm not sure what am I missing or where I am going wrong, should be very basic stuff...
In case it is important, here's dev dep list too:
"devDependencies": {
"#babel/core": "^7.8.7",
"#babel/preset-env": "^7.8.7",
"babel-loader": "^8.0.6",
"install": "^0.13.0",
"npm": "^6.14.7",
"ts-loader": "^6.2.1",
"typescript": "^3.8.3",
"webpack": "^4.43.0",
"webpack-cli": "^3.3.12",
"webpack-dev-middleware": "^3.7.2",
"webpack-dev-server": "^3.11.0",
"webpack-merge": "^5.0.9"
}
Made it work, although not sure if this is the best way.
Basically, instead of adding multiple entries in the export's entry section, I've created index.js file which reexported all the exports from the files I needed:
require('./src/ut');
require('./src/zd');
export * from './src/ut';
export * from './src/zd'
Entry is now just index.js
entry: {
'core' : 'index.js'
},
Works as intended, but I am not sure why wouldn't webpack automate this, and why would I have to export everything myself...
I'm struggling with what I feel shouldn't be too hard of a setup.
I want these three technologies to work together:
webpack to bundle code
babel so that I'm able to write modern JavaScript
flow because type checking is helpful just like tests and linter
I've already gone trough several setups of this but none of the articles I've found on the web appears to be helpful.
I've defined 3 scripts in my package.json, run, flow and build.
Typechecking with yarn run flow works perfectly, and so does executing the script trough babel-node using yarn run start.
But when I execute yarn run build the following error appears trough webpack:
$ ./node_modules/webpack/bin/webpack.js
Hash: 207d42dac5784520fc99
Version: webpack 3.10.0
Time: 49ms
Asset Size Chunks Chunk Names
bundle.js 2.65 kB 0 [emitted] main
[0] ./src/main.js 181 bytes {0} [built] [failed] [1 error]
ERROR in ./src/main.js
Module parse failed: Unexpected token (3:5)
You may need an appropriate loader to handle this file type.
| // #flow
|
| type Foo = {
| foo: string,
| };
error Command failed with exit code 2.
It appears to me that the type annotations don't get removed correctly at the right point. Sadly this also happend if I specify the babel options in webpack directly as opposed to the .babelrc.
This currently defeats me in bundling up a bunch of .js files whilst using flow and while I found several plugins that supposedly strip flow annotations simply using the flow preset is what flowtype.org appears to recommend.
For reproducibillity, my project files look like this:
package.json:
{
…
"dependencies": {},
"devDependencies": {
"babel-cli": "^6.26.0",
"babel-core": "^6.26.0",
"babel-eslint": "^8.0.3",
"babel-loader": "^7.1.2",
"babel-preset-env": "^1.6.1",
"babel-preset-flow": "^6.23.0",
"flow-bin": "^0.60.1",
"webpack": "^3.9.1"
},
"scripts": {
"build": "./node_modules/webpack/bin/webpack.js",
"start": "./node_modules/babel-cli/bin/babel-node.js src/main.js",
"flow": "./node_modules/flow-bin/cli.js"
}
}
.flowconfig:
[include]
./src
[ignore]
[libs]
[lints]
[options]
.babelrc:
{
"presets": ["env", "flow"]
}
webpack.config.js:
const path = require('path');
const webpack = require('webpack');
module.exports = {
entry: './src/main.js',
output: {
path: __dirname,
filename: 'bundle.js',
},
resolve: {
modules: [
path.resolve('./src/'),
'node_modules',
],
extensions: ['.js'],
},
module: {
rules: [
{
test: '/.js$/',
loader: 'babel-loader',
},
],
},
};
src/main.js:
// #flow
type Foo = {
foo: string,
};
const defaultFoo: Foo = {
foo: 'bar',
};
console.log(defaultFoo);
Download the relevant presets and add them to the webpack.config.js as follows:
module: {
rules: [
{
test: /\.js$/,
exclude: /(node_modules|bower_components)/,
use: {
loader: 'babel-loader',
options: {
presets: ['es2015', 'stage-0', 'react']
}
}
}
]
}
I have the following test component in my react app:
test2: function () {
return (
<div class="dropdown">
<button class="btn btn-secondary dropdown-toggle" type="button" id="dropdownMenuButton" data-t
oggle="dropdown" aria-haspopup="true" aria-expanded="true">
Dropdown button
</button>
<div class="dropdown-menu" aria-labelledby="dropdownMenuButton">
<a class="dropdown-item" href="#">Action</a>
<a class="dropdown-item" href="#">Another action</a>
<a class="dropdown-item" href="#">Something else here</a>
</div>
</div>
);
},
I import bootstrap like:
import 'bootstrap'
I import the scss via my top level scss file and the styling works fine. The issue is that I cannot get the JS to work. When I click on the dropdown button nothing happens. It looks like the files are not loading.
I do get this error in the js when I click the button:
popper.setAttribute('x-placement', placement);
"cannot read property setAttribute of undefined"
but I cannot figure out why popper is not defined. I have installed it with NPM and added to to Webpack config.
Any idea why I am having this issue?
My Webpack config is:
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: [
// 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'),
// We ship a few polyfills by default:
require.resolve('./polyfills'),
// Errors should be considered fatal in development
require.resolve('react-error-overlay'),
// 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: {
// Next line is not used in dev but WebpackDevServer crashes without it:
path: paths.appBuild,
// 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
devtoolModuleFilenameTemplate: info =>
path.resolve(info.absoluteResourcePath),
},
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
extensions: ['.js', '.json', '.jsx', '.es6'],
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',
'_': '../node_modules/underscore/underscore.js'
},
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),
],
},
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)$/,
enforce: 'pre',
use: [
{
options: {
formatter: eslintFormatter,
},
loader: require.resolve('eslint-loader'),
},
],
include: paths.appSrc,
},
// ** ADDING/UPDATING LOADERS **
// The "file" loader handles all assets unless explicitly excluded.
// The `exclude` list *must* be updated with every change to loader extensions.
// When adding a new loader, you must add its `test`
// as a new entry in the `exclude` list for "file" loader.
// "file" loader makes sure those assets get served by WebpackDevServer.
// When you `import` an asset, you get its (virtual) filename.
// In production, they would get copied to the `build` folder.
{
exclude: [
/\.es6$/,
/\.html$/,
/\.(js|jsx)$/,
/\.css$/,
/\.json$/,
/\.bmp$/,
/\.gif$/,
/\.jpe?g$/,
/\.png$/,
/\.sass$/,
/\.scss$/,
],
loader: require.resolve('file-loader'),
options: {
name: 'static/media/[name].[hash:8].[ext]',
},
},
// "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)$/,
include: paths.appSrc,
loader: require.resolve('babel-loader'),
options: {
// This is a feature of `babel-loader` for webpack (not Babel itself).
// It enables caching results in ./node_modules/.cache/babel-loader/
// directory for faster rebuilds.
cacheDirectory: true,
},
},
// "postcss" loader applies autoprefixer to our CSS.
// "css" loader resolves paths in CSS and adds assets as dependencies.
// "style" loader turns CSS into JS modules that inject <style> tags.
// In production, we use a plugin to extract that CSS to a file, but
// in development "style" loader enables hot editing of CSS.
//
{ test: /\.scss$/, loader: 'style-loader!css-loader!sass-loader'},
{
test: /\.css$/,
use: [
require.resolve('style-loader'),
{
loader: require.resolve('css-loader'),
options: {
importLoaders: 1,
},
},
{
loader: require.resolve('postcss-loader'),
options: {
plugins: function () { // post css plugins, can be exported to postcss.config.js
return [
require('precss'),
require('autoprefixer')
];
}
},
},
],
},
// ** STOP ** Are you adding a new loader?
// Remember to add the new extension(s) to the "file" loader exclusion list.
],
},
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,
}),
// 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$/),
new webpack.ProvidePlugin({
$: 'jquery',
jQuery: 'jquery',
'window.jQuery': 'jquery',
Popper: ['popper.js', 'default']
})
],
// 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: {
fs: 'empty',
net: 'empty',
tls: '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,
},
};
My Package.json
{
"proxy": "http://localhost:3001/",
"name": "client",
"version": "0.1.0",
"private": true,
"dependencies": {
"bootstrap": "^4.0.0-beta.2",
"foundation-sites": "^6.4.2",
"hjs-webpack": "^9.1.0",
"jquery": "^3.2.1",
"popper.js": "^1.12.9",
"react": "^15.6.2",
"react-addons-css-transition-group": "^15.6.0",
"react-bootstrap": "^0.31.5",
"react-dom": "^15.6.2",
"react-loader": "^2.4.2"
},
"devDependencies": {
"autoprefixer": "7.1.0",
"babel-core": "6.24.1",
"babel-eslint": "7.2.3",
"babel-jest": "20.0.3",
"babel-loader": "7.0.0",
"babel-preset-react-app": "^3.0.0",
"babel-runtime": "6.23.0",
"case-sensitive-paths-webpack-plugin": "1.1.4",
"chalk": "1.1.3",
"css-loader": "0.28.1",
"dotenv": "4.0.0",
"eslint": "3.19.0",
"eslint-config-react-app": "^1.0.4",
"eslint-loader": "1.7.1",
"eslint-plugin-flowtype": "2.33.0",
"eslint-plugin-import": "2.2.0",
"eslint-plugin-jsx-a11y": "5.0.3",
"eslint-plugin-react": "7.0.1",
"extract-text-webpack-plugin": "2.1.0",
"file-loader": "0.11.1",
"fs-extra": "3.0.1",
"html-webpack-plugin": "2.28.0",
"jest": "20.0.3",
"node-sass": "^4.5.3",
"object-assign": "4.1.1",
"postcss-flexbugs-fixes": "3.0.0",
"postcss-loader": "2.0.5",
"promise": "7.1.1",
"react-dev-utils": "^3.0.0",
"react-error-overlay": "^1.0.7",
"sass-loader": "^6.0.6",
"style-loader": "0.17.0",
"sw-precache-webpack-plugin": "0.9.1",
"underscore": "^1.8.3",
"url-loader": "0.5.8",
"webpack": "2.6.1",
"webpack-dev-server": "2.4.5",
"webpack-manifest-plugin": "1.1.0",
"whatwg-fetch": "2.0.3"
},
That's not how it works!
You need to import specific components you want to use if you want to use react-bootstrap!
https://medium.com/#victorleungtw/how-to-use-webpack-with-react-and-bootstrap-b94d33765970
I am leaning webpack. However, here comes a bug that "You may need an appropriate loader to handle this file type.", I have checked the webpack.config.js, it is correct.
const path = require('path');
const HtmlWebpackPlugin = require('html-webpack-plugin');
const CleanWebpackPlugin = require('clean-webpack-plugin');
const webpack = require("webpack");
module.exports = {
entry: {
app: './src/main.js',
print: './src/print.js'
},
devtool: 'inline-source-map',
devServer: {
contentBase: 'dist',
hot: true,
},
output: {
filename: '[name].bundle.js',
path: path.resolve(__dirname, 'dist')
},
module: {
rules: [{
test: /\.css$/,
use: [
'style-loader',
'css-loader'
]
}]
},
plugins: [
new CleanWebpackPlugin(['dist']),
new HtmlWebpackPlugin({
title: 'Output Management'
}),
new webpack.HotModuleReplacementPlugin()
]
};
Additionally, here is my js file and css file:
import './style.css';
body {
background-color: blue;
}
And the console log this:
./src/style.css
Module parse failed: D:\FrontEndWorkSpace\webpack-demo\src\style.css Unexpected token (1:5)
You may need an appropriate loader to handle this file type.
| body {
| background-color: blue;
| }
Additional, I have already installed both style-loader and css-loader, here are my dependencies on my package.json:
"devDependencies": {
"clean-webpack-plugin": "^0.1.16",
"css-loader": "^0.28.4",
"csv-loader": "^2.1.1",
"file-loader": "^0.11.2",
"html-webpack-plugin": "^2.29.0",
"style-loader": "^0.18.2",
"webpack": "^3.4.1",
"webpack-dev-server": "^2.6.1",
"xml-loader": "^1.2.1"
}
EDIT: For some unknown reasons, it's works.
Make sure you have installed the loaders you're trying to use from NPM. You should see them in both your package.json file and in your node_modules folder of the project. If you don't see them, you can install them and save them to your dev dependencies in your terminal:
$ npm install style-loader css-loader --save-dev
Last bit, I've found this YouTube video series extremely helpful in getting started with Webpack 2. It's changed a lot in its first couple of years, so relevant references are tricky to separate from the obsolete ones.
Good luck taming the webpack beast!
EDIT: Removed extra stuff.
Here's where I'm now:
package.json:
{
"dependencies": {
"css-loader": "^0.26.0",
"html-webpack-plugin": "^2.24.1",
"node-sass": "^3.13.0",
"sass-loader": "^4.0.2",
"style-loader": "^0.13.1",
"webpack": "^1.13.3"
}
}
webpack.config.js:
var HtmlWebpackPlugin = require('html-webpack-plugin');
module.exports = {
entry: './1.js',
output: {
path: 'dist',
filename: 'bundle.js',
},
module: {
loaders: [
{test: /\.sass$/, loaders: ['style', 'css?sourceMap', 'sass?sourceMap']},
]
},
plugins: [
new HtmlWebpackPlugin,
],
};
1.js:
require('./1.sass');
1.sass:
body
background: #ddd
Then
$ rm -f dist/* && ./node_modules/.bin/webpack
And open http://example.com/dist in Chrome. Then open Developer Tools > Sources > top > webpack:// > . > 1.sass. And there you'll see css code, not sass code. devtool is for js/coffeescript/whatever, if anything. What am I doing wrong?
UPD
From what I can see, sass-loader passes file as a string. And in that case node-sass (libsass) doesn't return source map. But even if given file, the latter returns source map with generated css code, not sass code for some reason. Any workarounds are welcome, even if ugly.
Well, the issue with libsass not generating source maps for inline content seems to be taken care of. It's just that libsass returns source maps with scss code, even if given sass code. So I mistook it for css.