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Cypress: import modules via alias

in my project i am using cypress with plain javascript. i am facing the challenge of importing the modules (page objects) via aliases instead of spaghetti code like ../../../../folder/page.js.
I don't use typescript or react.js and don't have a src folder/directory.
my tests run locally in the browser or via a docker image (pipeline).
I would like to transform from this:
import { LoginPage } from "../../pages/loginPage.js";
to something like this:
import { LoginPage } from "#Pages/loginPage.js";
but I always get an error:
Error: Webpack Compilation Error
./cypress/e2e/accountOverview/accountOverviewPageTest.spec.js
Module not found: Error: Can't resolve 'Pages/loginPage.js' in 'C:\Users\User\automated_frontend_tests\automated_frontend_tests\cypress\e2e\accountOverview'
resolve 'Pages/loginPage.js' in 'C:\Users\User\automated_frontend_tests\automated_frontend_tests\cypress\e2e\accountOverview'
Parsed request is a module
using description file: C:\Users\User\automated_frontend_tests\automated_frontend_tests\package.json (relative path: ./cypress/e2e/accountOverview)
Field 'browser' doesn't contain a valid alias configuration
Looked for and couldn't find the file at the following paths:
[C:\Users\User\automated_frontend_tests\automated_frontend_tests\cypress\e2e\accountOverview\node_modules]
[C:\Users\User\automated_frontend_tests\automated_frontend_tests\cypress\e2e\node_modules]
[C:\Users\User\automated_frontend_tests\automated_frontend_tests\cypress\node_modules]
[C:\Users\node_modules]
[C:\node_modules]
[C:\Users\User\automated_frontend_tests\automated_frontend_tests\node_modules\Pages\loginPage.js]
[C:\Users\User\automated_frontend_tests\node_modules\Pages\loginPage.js]
[C:\Users\User\node_modules\Pages\loginPage.js]
[C:\Users\User\automated_frontend_tests\automated_frontend_tests\node_modules\Pages\loginPage.js.js]
[C:\Users\User\automated_frontend_tests\node_modules\Pages\loginPage.js.js]
[C:\Users\User\node_modules\Pages\loginPage.js.js]
[C:\Users\User\automated_frontend_tests\automated_frontend_tests\node_modules\Pages\loginPage.js.json]
[C:\Users\User\automated_frontend_tests\node_modules\Pages\loginPage.js.json]
[C:\Users\User\node_modules\Pages\loginPage.js.json]
[C:\Users\User\automated_frontend_tests\automated_frontend_tests\node_modules\Pages\loginPage.js.jsx]
[C:\Users\User\automated_frontend_tests\node_modules\Pages\loginPage.js.jsx]
[C:\Users\User\node_modules\Pages\loginPage.js.jsx]
[C:\Users\User\automated_frontend_tests\automated_frontend_tests\node_modules\Pages\loginPage.js.mjs]
[C:\Users\User\automated_frontend_tests\node_modules\Pages\loginPage.js.mjs]
[C:\Users\User\node_modules\Pages\loginPage.js.mjs]
[C:\Users\User\automated_frontend_tests\automated_frontend_tests\node_modules\Pages\loginPage.js.coffee]
[C:\Users\User\automated_frontend_tests\node_modules\Pages\loginPage.js.coffee]
[C:\Users\User\node_modules\Pages\loginPage.js.coffee]
# ./cypress/e2e/accountOverview/accountOverviewPageTest.spec.js 5:17-46
I have tried several solutions, including:
//webpack.config.js
module.exports = {
resolve: {
alias: {
"#pages": path.resolve(__dirname, "cypress/pages/*"),
},
},
};
//testspec file
import { LoginPage } from "#pages/loginPage.js";
const loginPage = new LoginPage();
#Uzair Khan:
I tried your solution, but it still didn't work. The error message remains the same. It seems that the IDE does not search in the correct folder, but only in ...\node_modules\#page\loginPage.js which makes no sense.
If I enter const loginPage = new LoginPage(), the module LoginPage() cannot be found by the IDE either. Something is wrong with the solution. Do I still have to install any packages via NPM?

In your webpack.config.js file add resolve.alias which you want to make alias. It looks like something this below:
resolve: {
alias: {
'#page': path.resolve(__dirname, '{path you want to make alias}')
}
}
Since you are using cypress, you have to update the resolve path in cypress.config.js. Here is mine cypress.config.js
import { defineConfig } from 'cypress'
import webpack from '#cypress/webpack-preprocessor'
import preprocessor from '#badeball/cypress-cucumber-preprocessor'
import path from 'path'
export async function setupNodeEvents (on, config) {
// This is required for the preprocessor to be able to generate JSON reports after each run, and more,
await preprocessor.addCucumberPreprocessorPlugin(on, config)
on(
'file:preprocessor',
webpack({
webpackOptions: {
resolve: {
extensions: ['.ts', '.js', '.mjs'],
alias: {
'#page': path.resolve('cypress/support/pages/')
}
},
module: {
rules: [
{
test: /\.feature$/,
use: [
{
loader: '#badeball/cypress-cucumber-preprocessor/webpack',
options: config
}
]
}
]
}
}
})
)
// Make sure to return the config object as it might have been modified by the plugin.
return config
}
And import in other file via that alias you set in cypress.config.js. Here is mine for example:
import page from '#page/visit.js'
const visit = new page()
When('I visit duckduckgo.com', () => {
visit.page()
})

I think both answers are nearly there, this is what I have for src files:
const webpack = require('#cypress/webpack-preprocessor')
...
module.exports = defineConfig({
...
e2e: {
setupNodeEvents(on, config) {
...
// #src alias
const options = {
webpackOptions: {
resolve: {
alias: {
'#src': path.resolve(__dirname, './src')
},
},
},
watchOptions: {},
}
on('file:preprocessor', webpack(options))
...
path.resolve() resolves a relative path into an absolute one, so you need to start the 2nd param with ./ or ../.
Also, don't use wildcard * in the path, you just need a single folder that will be substituted for the alias in the import statement.
If in doubt, check the folder returned (in the terminal)
module.exports = defineConfig({
...
e2e: {
setupNodeEvents(on, config) {
const pagesFolder = path.resolve(__dirname, './cypress/pages')
console.log('pagesFolder', pagesFolder)

Set multiple entries using react-app-rewired

Below are some options from an open-webpack (not CRA) react project:
// webpack.config.js
module.exports = {
// ...
entry: {
main: './src/index.js',
'editor.worker': 'monaco-editor/esm/vs/editor/editor.worker.js',
'yaml.worker': 'monaco-yaml/lib/esm/yaml.worker.js',
},
// ...
How to implement similar configuration in config-overrides.js (using react-app-rewired)?
// config-overrides.js
module.exports = function override (config) {
config.entry = // ???
return config
}
My experience:
Simply set it to:
config.entry = {
main: './src/index.js',
'editor.worker': 'monaco-editor/esm/vs/editor/editor.worker.js',
'yaml.worker': 'monaco-yaml/lib/esm/yaml.worker.js',
}
doesn't work. It even causes issues in loading index.js!

config.optimization.runtimeChunk = 'single'
maybe help you ...
https://webpack.js.org/configuration/optimization/#optimizationruntimechunk

Create class instance and inject it dynamically

My project is using Nuxt, and I would like to implement dynamic injection of my services. It means I just add a class to my specific folder, and the class will be automatically injected into the context.
For instance, these are my classes placed in nuxtApp/service:
// /service/foo.service.js
export class FooService {
constructor (context) {
this.context = context
}
functionFoo (param) {
console.log(`FooService.functionFoo: ${param}`)
}
}
// /service/bar.service.js
export class BarService {
constructor (context) {
this.context = context
}
functionBar (param) {
console.log(`BarService.functionBar: ${param}`)
}
}
And this is how my plugin currently looks like, but I would like to automate it:
// /plugins/service-loader.js
import { FooService } from '../service/foo.service'
import { BarService } from '../service/bar.service'
export default ({ app }, inject) => {
const fooService = new FooService(app)
inject('fooService', fooService)
const barService = new BarService(app)
inject('barService', barService)
}
Is it possible to create automatically loading of services placed in the /service folder, and then inject their instance into the context?

You could use a Nuxt module to provide plugins for ~/service/*.service.js. The module would scan the service/ directory, and call addPlugin() for each .service.js file:
// ~/modules/service-loader.js
import path from 'path'
import glob from 'glob'
export default function serviceLoader() {
glob(path.resolve(__dirname, '../service/**/*.service.js'), { follow: true }, (err, files) => {
if (err) throw err
for (const file of files) {
const exportedMembers = Object.keys(require(file))
if (!exportedMembers.length) return
const className = exportedMembers[0]
this.addPlugin({
src: path.resolve(__dirname, './service-template.js'),
fileName: path.basename(file),
options: {
className,
propName: className.slice(0,1).toLowerCase() + className.substring(1),
moduleName: file,
}
})
}
})
}
// ~/modules/service-template.js
import { <%= options.className %> } from '<%= options.moduleName %>'
export default ({ app }, inject) => {
const <%= options.propName %> = new <%= options.className %> (app)
inject('<%= options.propName %>', <%= options.propName %>)
}
Install this module under the modules array in your Nuxt config:
// nuxt.config.js
export default {
modules: [
'~/modules/service-loader'
],
}

Require doesn't appear in my code, but webpack keeps throwing the error "require is not defined."

I'm writing an electron app with react. I run the developement version using this command:
webpack-dev-server --hot --host 0.0.0.0 --port 4000 --config=./webpack.dev.config.js
Here is the webpack.dev.config.js file
const webpack = require('webpack');
const path = require('path');
const HtmlWebpackPlugin = require('html-webpack-plugin');
const { spawn } = require('child_process');
const helpers = require('./config/helpers');
// Config directories
const SRC_DIR = path.resolve(__dirname, 'src');
const OUTPUT_DIR = path.resolve(__dirname, 'dist');
// Any directories you will be adding code/files into, need to be added to this array so webpack will pick them up
const defaultInclude = [SRC_DIR];
module.exports = {
entry: SRC_DIR + '/index.js',
output: {
path: OUTPUT_DIR,
publicPath: '/',
filename: 'bundle.js'
},
module: {
rules: [
{
test: /\.css$/,
use: [{ loader: 'style-loader' }, { loader: 'css-loader' }],
include: defaultInclude
},
{
test: /\.jsx?$/,
use: [{ loader: 'babel-loader' }],
include: defaultInclude
},
{
test: /\.(jpe?g|png|gif)$/,
use: [{ loader: 'file-loader?name=img/[name]__[hash:base64:5].[ext]' }],
include: defaultInclude
},
{
test: /\.(eot|svg|ttf|woff|woff2)$/,
use: [{ loader: 'file-loader?name=font/[name]__[hash:base64:5].[ext]' }],
include: defaultInclude
}
]
},
target: 'electron-renderer',
plugins: [
new HtmlWebpackPlugin({
template: helpers.root('public/index.html'),
inject: 'body'
}),
new webpack.DefinePlugin({
'process.env.NODE_ENV': JSON.stringify('development')
})
],
devtool: 'cheap-source-map',
devServer: {
contentBase: OUTPUT_DIR,
stats: {
colors: true,
chunks: false,
children: false
},
setup() {
spawn(
'electron',
['.'],
{ shell: true, env: process.env, stdio: 'inherit' }
)
.on('close', code => {
console.error("electron exited with code ", code);
process.exit(0)
})
.on('error', spawnError => console.error(spawnError));
}
}
};
Once the electron browser opens it has the following error in the Dev-Tools console.
Uncaught ReferenceError: require is not defined
at Object.url (index.js:23)
at __webpack_require__ (bootstrap:709)
at fn (bootstrap:94)
at Object../node_modules/webpack-dev-server/client/utils/createSocketUrl.js (createSocketUrl.js:4)
at __webpack_require__ (bootstrap:709)
at fn (bootstrap:94)
at Object.<anonymous> (client:20)
at Object../node_modules/webpack-dev-server/client/index.js?http://0.0.0.0:4000 (client:176)
at __webpack_require__ (bootstrap:709)
at fn (bootstrap:94)
The place where it claims this is occurring is at index.js:23.
Here is the build version of index.js:
import React from "react";
import { render } from "react-dom";
import { Provider } from "react-redux";
import App from "./components/App";
import { createStore, applyMiddleware } from "redux";
import thunk from "redux-thunk";
import { ipcRenderer as ipc } from "electron";
import { onUpdate } from "./actions/workerActions";
import { RECEIVED_STATE } from "./actions/types";
import "./assets/css/index.css";
import rootReducer from "./reducers/rootReducer";
import defaultState from "../config/defaultstate"; //Setup redux store
const middleware = [thunk];
const store = createStore(rootReducer, defaultState, applyMiddleware(...middleware));
ipc.on(RECEIVED_STATE, arg => {
console.log("Recieved State: ", arg);
onUpdate(arg)(store.dispatch);
}); // Now we can render our application into it
render(React.createElement(Provider, {
store: store
}, React.createElement(App, null)), document.getElementById("app"));
As you can see require does not appear here and all of the import aside from ipcRender are designed to run client-side, and therefore should not use required. I tried commenting out the ipcRender import but it resulted in the exact same error.
Most puzzlingly of all, I get the exact same error even with the entire index.js file commented out. The console still claiming the block comment contains a reference to require, which is not defined.

If you're using webpack directly then make sure you have the following in the webpack config that targets your renderer code.
// webpack.config.js
...
module.exports = {
...
target: 'web',
...
}
If you're using Vue then you'll need something like the following:
// vue.config.js
...
module.exports = {
...
configureWebpack: {
target: 'web'
},
...
}
Or, in my case I was using vue-cli-plugin-electron-builder and so need the following:
// vue.config.js
...
module.exports = {
...
pluginOptions: {
electronBuilder: {
nodeIntegration: false,
chainWebpackRendererProcess: config => {
config.target('web');
}
}
},
...
}

It turns out that the error is caused by importing electron's ipcRenderer which requires node integration and uses require. The reason that commenting out the import in the index.js didn't fix the error was because it was imported in other files.

How can I replace files at compile time using webpack?

I have a project with miltiple configuration. The first config is config.dev.js file that contains some development configiration. I using it in development mode. The second config is config.js file. I using it in production mode.
In the code I using imports:
import * as config from './config.js';
I want to use the first config file in development and the second to production whithout rewriting all of the imports. How can I replace this config depending on the build mode?

This is an old question but I've recently stumbled across the same issue and webpack.NormalModuleReplacementPlugin doesn't seem to work anymore (or at least not in my case, where I used JSON files as config). Instead I found another solution using alias:
const path = require("path");
modules.export = {
...
resolve: {
...
alias: {
[path.resolve(__dirname, "src/conf/config.json")]:
path.resolve(__dirname, "src/conf/config.prod.json")
}
}
...
}

I realize this is an old post, but this is one of the first results on Google, so I thought a better answer would be good.
Webpack has a built in "Normal Module Replacement Plugin".
plugins: [
new webpack.NormalModuleReplacementPlugin(
/some\/path\/config\.development\.js/,
'./config.production.js'
)
]
For my use, I put the env file in a variable Here is an example:
let envFilePath = './environment.dev.js';
if (env === 'production') {
envFilePath = './environment.prod.js';
} else if (env === 'staging') {
envFilePath = './environment.stg.js';
}
module.exports = {
// other webpack stuff
....
plugins:[
new webpack.NormalModuleReplacementPlugin(
/src\/environment\/environment\.js/,
envFilePath
),
...
]
}

You can use webpack file-replace-loader
https://www.npmjs.com/package/file-replace-loader
Example:
//webpack.config.js
const resolve = require('path').resolve;
module.exports = {
//...
module: {
rules: [{
test: /\.config\.js$/,
loader: 'file-replace-loader',
options: {
condition: process.env.NODE_ENV === 'development',
replacement: resolve('./config.dev.js'),
async: true,
}
}]
}
}

I wanted to imitate the Angular fileReplacements syntax so I used a config.json like Angular's and if the configuration key matches the env I pass to webpack, loop through the replacements and create several Webpack module rules.
It's not the most elegant thing ever but this is what I ended up with:
// config.json
{
"title": "Some Title",
"configurations": {
"production": {
"fileReplacements": [
{
"replace": "src/environments/environment.ts",
"with": "src/environments/environment.prod.ts"
}
]
},
"lan": {
"fileReplacements": [
{
"replace": "src/environments/environment.ts",
"with": "src/environments/environment.lan.ts"
}
]
}
}
}
// webpack.config.js
const appConfig = require('./config.json');
module.exports = (env, argv) => {
// env.build is like `ng build --prod` as `webpack --env.build=production`
const configuration = appConfig.configurations[env.build];
const fileReplacements = [];
// Safety Check
if(configuration && configuration.fileReplacements) {
// Iterate through replacements
for(const replacement of configuration.fileReplacements) {
// create Webpack module rule
const replace = {
test: path.resolve(replacement.replace),
loader: 'file-replace-loader',
options: {
replacement: path.resolve(replacement.with),
async: true
}
}
fileReplacements.push(replace);
}
}
return {
mode: //...
entry: //...
module: {
rules: [
{
//...
},
// Unpack anywhere here
...fileReplacements
]
}
}
}
This way you don't have to keep messing with webpack and regex tests, just add to the array in config.json

You can also use babel-loader like this:
//webpack.config.js
const resolve = require('path').resolve;
module.exports = {
//...
module: {
strictExportPresence: true,
rules: [{
test: /\.config\.js$/,
include: paths.appSrc,
loader: require.resolve('babel-loader'),
options: {
plugins: [
[
"module-resolver",
{
resolvePath(sourcePath, currentFile, opts) {
if(process.env.NODE_ENV === 'development') {
return sourcePath.substr(0, sourcePath.lastIndexOf('/')) + '/config.dev.js';
} else {
return sourcePath;
}
}
}
]
]
}
}]
}
}
This way you can even define complex algorithms to determine which file you wanna use.

Another way is to use Webpack.DefinePlugin. Especially useful if you have a tiny code block that you want to be included conditionally.
Example follows:
// webpack.conf.js
// Code block that should be inserted or left blank
const ServiceWorkerReg = `window.addEventListener('load', () => {
navigator.serviceWorker.register('service-worker.js').then(registration => {
console.log('SW registered: ', registration);
}).catch(registrationError => {
console.log('SW registration failed: ', registrationError);
});
});`
appConfig = {
plugins: [
new webpack.DefinePlugin({
__SERVICE_WORKER_REG: isDev ? '' : ServiceWorkerReg,
}),
]
...
}
// Some module index.js
__SERVICE_WORKER_REG
... // other non conditional code