Develop Reference

Webpack can't resolve file loader js files

I keep getting this error
Can't resolve 'file-loader'
I am running webpack serve command.
I've tried different regex but it always shows the same mistake. if this may have something to do with the way in which the React files are placed let me know.
package.json
{
"name": "Tick",
"version": "1.0.0",
"description": "Productivity app",
"main": "src/server/app.js",
"scripts": {
"test": "echo \"Error: no test specified\" && exit 1",
"server": "nodemon src/server/app.js",
"dev": "webpack serve",
"build": "webpack"
},
"author": "Gabriel Gamboa",
"license": "ISC",
"dependencies": {
"cross-env": "^7.0.3",
"express": "^4.17.1",
"nodemon": "^2.0.13",
"react": "^17.0.2",
"react-dom": "^17.0.2",
"react-router-dom": "^5.3.0"
},
"devDependencies": {
"#babel/core": "^7.15.5",
"#babel/preset-env": "^7.15.6",
"#babel/preset-react": "^7.14.5",
"babel-loader": "^8.2.2",
"html-webpack-plugin": "^5.3.2",
"webpack": "^5.54.0",
"webpack-cli": "^4.8.0",
"webpack-dev-server": "^4.3.0"
}
}
Webpack config
const path = require('path');
const HtmlWebpackPlugin = require('html-webpack-plugin');
module.exports = {
entry: path.join(__dirname, "src", "client", "index.js"),
mode: 'development',
output: {
path:path.resolve(__dirname, "dist"),
},
module: {
rules: [
{
test: /\.js$/,
exclude: /node_modules/,
use: [{
loader: "babel-loader",
options: {
presets: ['#babel/preset-env', '#babel/preset-react']
}
}]
},
{
test: /\.(png|jp(e*)g|svg|gif)$/,
use: ['file-loader'],
}
]
},
plugins: [
new HtmlWebpackPlugin({
template: path.join(__dirname, "src", "client", "index.html"),
}),
],
}
Please help I've tried everything

You need to install it as it is not listed in your package.json file as a dependency.
npm i file-loader -D

ReferenceError: require is not defined #react

I made my own react component npm package and published in npm, now when import and use it in other CRA apps, i get this error when npm start in run in command line .
and in console:
My webpack.config.js file:
var webpack = require('webpack');
var path = require('path');
var nodeExternals = require('webpack-node-externals');
module.exports = {
target: 'web',
entry: './src/index.js',
output: {
path: path.resolve(__dirname, 'build'),
filename: 'index.js',
libraryTarget: 'commonjs2'
},
module: {
rules: [
{
test: /\.js$/,
include: path.resolve(__dirname, 'src'),
exclude: /(node_modules|bower_components|build)/,
use: {
loader: 'babel-loader',
options: {
presets: ['env']
}
}
},
{
test: /\.css$/i,
use: ['style-loader', 'css-loader'],
},
{
test: /\.(png|jpg|woff|woff2|eot|ttf|svg)(\?v=[0-9]\.[0-9]\.[0-9])?$/,
loader: 'url?limit=512&&name=[path][name].[ext]?[hash]'
}
]
},
mode: 'development',
externals: {
'react': 'commonjs react'
}
};
My package.json file:
{
"name": "primetable1",
"version": "1.0.0",
"description": "A Datatable for react apps based on Primereact",
"main": "build/index.js",
"scripts": {
"test": "echo \"Error: no test specified\" && exit 1",
"start": "webpack --watch",
"build": "webpack"
},
"keywords": [
"primereact",
"primeicons"
],
"author": "Anish Arya",
"license": "ISC",
"peerDependencies": {
"react": "^16.4.0",
"react-dom": "^16.4.0"
},
"devDependencies": {
"babel-cli": "^6.26.0",
"babel-core": "^6.26.3",
"babel-loader": "^7.1.4",
"babel-plugin-transform-object-rest-spread": "^6.26.0",
"babel-plugin-transform-react-jsx": "^6.24.1",
"babel-preset-env": "^1.7.0",
"babel-runtime": "^6.26.0",
"css-loader": "^3.4.2",
"file-loader": "^5.0.2",
"react": "^16.4.0",
"react-dom": "^16.4.0",
"react-hot-loader": "^4.12.19",
"react-scripts": "3.4.0",
"style-loader": "^1.1.3",
"webpack-cli": "^3.3.11",
"webpack-node-externals": "^1.7.2"
},
"dependencies": {
"classnames": "^2.2.6",
"primeicons": "^2.0.0",
"primereact": "^3.4.0",
"react-transition-group": "^4.3.0"
}
}
My .babelrc file:
{
"presets": ["env"],
"plugins": [
"transform-object-rest-spread",
"transform-react-jsx",
"react-hot-loader/babel"
]
}
I followed this article to create and publish npm package:
https://codeburst.io/extracting-a-react-js-component-and-publishing-it-on-npm-2a49096757f5
How to solve this error?

The externals configuration seems wrong – you probably only need externals: [nodeExternals()] (from const nodeExternals = require("webpack-node-externals");).

Configure webpack for React to use multuple entries and outputs

I'm trying to config the server to have multiple entries and outputs. The app is using Zurb Foundation,jquery and React.
I want jquery and foundation not to be part of the bundle.js and also to have a separate bundle for react
Webpack validates, server starts but nothing is show and in console appears: "ReferenceError: webpackJsonp is not defined"
With a single entry is working, I don't know were is the error when trying to use multiple ones.
webpack.config
var webpack = require('webpack');
var path = require('path');
var CommonsChunkPlugin = require('./node_modules/webpack/lib/optimize/CommonsChunkPlugin');
module.exports = {
entry: {
main: ['script!jquery/dist/jquery.min.js',
'script!foundation-sites/dist/foundation.min.js',
'./dist/app.js' ],
react: ['react', 'react-dom']
},
externals: {
jquery: 'jQuery'
},
plugins: [
new webpack.ProvidePlugin({
'$': 'jquery',
'jQuery': 'jquery'
}),
new CommonsChunkPlugin('react', 'react.bundle.js')
],
output: {
filename: bundle.js'
},
devServer: {
inline: true,
contentBase: './build',
port: 3000
},
module: {
loaders: [
{
loader: 'babel-loader',
query: {
presets: ['react', 'es2015']
},
test: /\.js?$/,
exclude: /(node_modules)/
}
]
}
};
package.json
{
"name": "boilerplate",
"version": "1.0.0",
"description": "",
"main": "index.js",
"scripts": {
"build": "webpack",
"start": "webpack-dev-server",
"test": "karma start"
},
"author": "CBM",
"license": "MIT",
"dependencies": {
"react": "^15.3.2",
"react-dom": "^15.3.2"
},
"devDependencies": {
"babel-core": "^6.16.0",
"babel-loader": "^6.2.5",
"babel-preset-es2015": "^6.16.0",
"babel-preset-react": "^6.16.0",
"css-loader": "^0.25.0",
"foundation-sites": "^6.2.3",
"jquery": "^3.1.1",
"karma": "^1.3.0",
"karma-firefox-launcher": "^1.0.0",
"karma-mocha": "^1.2.0",
"karma-mocha-reporter": "^2.2.0",
"karma-sourcemap-loader": "^0.3.7",
"karma-webpack": "^1.8.0",
"mocha": "^3.1.0",
"react-router": "^2.8.1",
"script-loader": "^0.7.0",
"style-loader": "^0.13.1",
"webpack": "^1.13.2",
"webpack-dev-server": "^1.16.1"
}
}
babel.rc
{
"presets": ["es2015", "react"]
}

Specify an output for each entry:
entry: {
jquery: ['script!jquery/dist/jquery.min.js', 'script!foundation-sites/dist/foundation.min.js' ],
bundle: './dist/app.js',
react: ['react', 'react-dom']
},
output: {
filename: '[name].js'
}
If you want to add jquery and foundation libraries directly to the html just don't add the entries.
font: https://webpack.github.io/docs/multiple-entry-points.html

Webpack build step isn't generating build files

When I run npm build nothing seems to happen. When I look for the build files I don't see anything. npm start works fine though.
Package.json
{
"name": "pro-react-webpack",
"version": "1.0.0",
"description": "",
"main": "index.js",
"scripts": {
"start": "webpack-dev-server --progress",
"build": "NODE_ENV=production webpack --config ./webpack.production.config.js --progress",
"test": "echo \"Error: no test specified\" && exit 1"
},
"author": "",
"license": "ISC",
"devDependencies": {
"babel-core": "^6.10.4",
"babel-loader": "^6.2.4",
"babel-plugin-react-transform": "^2.0.2",
"babel-preset-es2015": "^6.9.0",
"babel-preset-react": "^6.11.1",
"css-loader": "^0.23.1",
"extract-text-webpack-plugin": "^1.0.1",
"html-webpack-plugin": "^2.22.0",
"json-loader": "^0.5.4",
"postcss-loader": "^0.9.1",
"precss": "^1.4.0",
"react-transform-hmr": "^1.0.4",
"style-loader": "^0.13.1",
"webpack": "^1.13.1",
"webpack-dev-server": "^1.14.1"
},
"dependencies": {
"react": "^15.2.1",
"react-dom": "^15.2.1"
}
}
Webpack.production.config.js
var webpack = require('webpack');
var HtmlWebpackPlugin = require('html-webpack-plugin');
var ExtractTextPlugin = require('extract-text-webpack-plugin');
module.exports = {
entry: __dirname + "/app/main.js",
output: {
path: __dirname + "/build",
filename: "bundle.js"
},
module: {
loaders: [
{
test: /\.json$/,
loader: "json"
},
{
test: /\.js$/,
exclude: /node_modules/,
loader: 'babel'
},
{
test: /\.css$/,
loader: ExtractTextPlugin.extract('style', 'css?modules!postcss')
}
]
},
postcss: [
require('autoprefixer')
],
plugins: [
new HtmlWebpackPlugin({
template: __dirname + "/app/index.tmpl.html"
}),
new webpack.optimize.OccurenceOrderPlugin(),
new webpack.optimize.UglifyJsPlugin(),
new ExtractTextPlugin("style.css")
]
}
I also have .babelrc file and webpack.config.js file, let me know if those would be useful to see as well, thanks.

Might be related to the fact that build is an internal command. Seems like I have had this happen to me as well in the past. Check out this Question
In order to run a custom script, you can use the npm run-script build or just npm run build. As stated in the NPM documentation

React app stopped reporting errors in the console such as usage of undefined variables, silently fails

I'm not sure what happened over the course of development, but I'm using React 0.13 with Webpack, and whenever I attempt to use an undefined variable, it fails to execute past that point. For example, even a simple console.log(anundefinedvariable); fails to execute (and no lines after that get run.) Nothing shows in the console, which makes it very difficult to debug.
I don't know where to begin to solve the issue. Where should I start?
Edit: actually now that I think about it, I might have done an npm update command -- maybe this somehow introduced this problem. Not sure what to do, still.
Edit2: My package.json:
{
"name": "app",
"version": "0.0.0",
"description": "",
"main": "src/index.js",
"directories": {
"doc": "docs"
},
"scripts": {
"start": "webpack-dev-server",
"test": "mocha --compilers js:babel-core/register --require ./test/test_helper.js 'test/**/*.#(js|jsx)'"
},
"author": "Name",
"license": "ISC",
"dependencies": {
"babel-plugin-object-assign": "^1.2.1",
"firebase": "^2.2.9",
"fireproof": "^3.0.3",
"immutable": "^3.7.5",
"lodash": "^3.10.1",
"q": "^1.4.1",
"react": "^0.13.3",
"react-redux": "^2.1.2",
"react-router": "^1.0.0-rc1",
"redux": "^3.0.0",
"redux-thunk": "^1.0.0"
},
"devDependencies": {
"babel-core": "^5.8.24",
"babel-loader": "^5.3.2",
"chai": "^3.3.0",
"chai-immutable": "^1.3.0",
"jsdom": "^3.1.2",
"mocha": "^2.3.3",
"react-hot-loader": "^1.3.0",
"webpack": "^1.12.2",
"webpack-dev-server": "^1.11.0"
}
}
My webpack config:
var webpack = require('webpack');
module.exports = {
entry: [
'webpack-dev-server/client?http://localhost:8080',
'webpack/hot/only-dev-server',
'./src/js/index.jsx'
],
module: {
loaders: [{
test: /\.jsx?$/,
exclude: /node_modules/,
loader: 'react-hot!babel?plugins=babel-plugin-object-assign'
}]
},
resolve: {
modulesDirectories: ["src/js/", "web_modules", "node_modules"],
extensions: ['', '.js', '.jsx']
},
output: {
path: __dirname + '/dist',
publicPath: '/',
filename: 'bundle.js'
},
devServer: {
contentBase: './dist',
hot: true
},
plugins: [
new webpack.HotModuleReplacementPlugin()
]
};