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Webpack can't resolve relative path import express static

I'm working on an outlook addin I have an express server running. I am setting webpack because I need to transpile js to es5 to make it work in Outlook Desktop. Here is the simplified project structure.
/public
/javascripts
ssoAuth.js
/addin
/commmands
commands.js
commands.html
/server
/bin
/helpers
app.js
The public folder is set as a static folder in my express server
app.use(express.static(path.join(__dirname, '../public'),
My problem is in commands.js I import ssoAuth.js with es6 module import with relative path :
import getGraphAccessToken from "/javascripts/ssoAuthES6.js";
It works fine when I run node ./server/app.js and load my outlook addin, but when I want to use Webpack to bundle, the import is not working, I get :
ERROR in ./addin/commands/commands.js
Module not found: Error: Can't resolve '/javascripts/ssoAuth.js'
I can't figure out how to configure webpack to allow the imports from the public folder.
Here are my webpack config files :
webpack.config.js :
const config = {
devtool: "source-map",
entry: {
polyfill: "#babel/polyfill",
commands: "./addin/commands/commands.js"
},
resolve: {
extensions: [".ts", ".tsx", ".html", ".js"]
},
module: {
rules: [
{
test: /\.js$/,
exclude: /node_modules/,
use: {
loader: "babel-loader",
options: {
presets: ["#babel/preset-env"]
}
}
},
{
test: /\.html$/,
exclude: /node_modules/,
use: "html-loader"
},
{
test: /\.(png|jpg|jpeg|gif)$/,
use: "file-loader"
}
]
},
plugins: [
new CleanWebpackPlugin(),
new HtmlWebpackPlugin({
filename: "commands.html",
template: "./addin/commands/commands.html",
chunks: ["polyfill", "commands"]
})
]};
webpack.server.config.js :
return ({
entry: {
server: './server/bin/www',
},
output: {
path: path.join(__dirname, 'dist'),
publicPath: '/',
filename: '[name].js'
},
target: 'node',
node: {
__dirname: false,
__filename: false,
},
externals: [nodeExternals()],
module: {
rules: [
{
// Transpiles ES6-8 into ES5
test: /\.js$/,
exclude: /node_modules/,
use: {
loader: "babel-loader"
}
}
]
},
plugins: [
new CopyWebpackPlugin([
{
to: "./public",
from: "./public"
}
])
]})
Can you help figure this out ? Is there a better folder structure that I should use to make it work ?
Thanks

You're using an absolute path
import getGraphAccessToken from "/javascripts/ssoAuthES6.js";
// ^ this will look in your topmost directory on your OS
The relative path, from commands.js, would be:
import getGraphAccessToken from "../../javascripts/ssoAuthES6.js";
Alternatively, you can set Webpack to look for modules from your root directory by adding the following to your webpack configuration:
{
// ...
resolve: {
modules: [path.resolve(__dirname, "src"), "node_modules"],
},
// ...
}
Then you can import from your project's root directory from anywhere, like so:
import getGraphAccessToken from "javascripts/ssoAuthES6.js";
Some other points:
Since you're setting the extensions: [".ts", ".tsx", ".html", ".js"], you don't need to provide file extensions for those imports
You specify .ts and .tsx in your webpack config, but you are using .js files. Consider removing the Typescript extensions
If you are using Typescript, you will need to update import paths in your tsconfig.json
You can consider import path aliases in both Webpack and Typescript to be more explicit that your imports are coming from your project root. Instructions here

Yarn Workspaces and Invalid Hook call

Having a lot of trouble trying to set up a common UI library.
I've set up a yarn workspace which looks like this:
/monorepo
/common-16.13
/react-app-16.8.
/another-app-16.13
I then import common-16.13 into react-app-16.8 and use one of the components like this:
/react-app/home.js
import {SharedComponent} from "common"
However when I run the application I get this error:
react.development.js?80c6:1465 Uncaught Error: Invalid hook call. Hooks can only be called inside of the body of a function component. This could happen for one of the following reasons:
1. You might have mismatching versions of React and the renderer (such as React DOM)
2. You might be breaking the Rules of Hooks
3. You might have more than one copy of React in the same app
Inside common I have:
/src/components/SharedComponent.jsx:
import React from 'react';
import { Box } from 'material-ui/core';
export const ShareComponent = ()=> <Box>SharedComponent</Box>;
/src/components/index.js:
export { SharedComponen t} from 'SharedComponent';
/src/index.js:
export {SharedComponent } from './components';
package.json:
{
"name": "#libs/common",
"main": "dist/index.js",
"scripts" {
"build": "webpack"
}
}
/common/webpack.config.json:
const webpack = require('webpack');
module.exports = env => {
// Each key value generate a page specific bundle
entry: {
index: './src/index.js'
},
output: {
path: path.resolve(ROOT_PATH, 'dist'),
publicPath: '/',
filename: 'index.js',
library: '#libs/common',
libraryTarget: 'umd'
},
module: {
rules: [
{
test: /\.(js|jsx)$/,
use: 'happypack/loader?id=jsx',
exclude: /node_modules/
}
]
},
// Automatically resolve below extensions
// Enable users to leave off the extensions when importing
resolve: {
symlinks: false,
extensions: ['*', '.js', '.jsx', '.css', '.scss']
},
plugins: [
new HappyPack({
id: 'css',
threadPool: happyThreadPool,
loaders: [
'cache-loader',
'style-loader',
{
loader: MiniCssExtractPlugin.loader,
options: {
hmr: true
}
},
'css-loader',
'sass-loader'
]
}),
new HappyPack({
id: 'jsx',
threadPool: happyThreadPool,
loaders: [
'cache-loader',
{
loader: 'babel-loader'
}
]
})
]
}
So I bundle common. Then in my react-app I yarn install #lib/common. Then I import SharedComponent into my react app:
/react-app/src/index.js:
import { SharedComponent } from '#libs/common';
/react-app/webpack.config.js:
{
// Each key value generate a page specific bundle
entry: {
index: './src/index.jsx',
},
module: {
rules: [
{
test: /\.(js|jsx)$/,
exclude: /node_modules/,
loader: 'babel-loader'
},
]
},
// Automatically resolve below extensions
// Enable users to leave off the extensions when importing
resolve: {
extensions: ['*', '.js', '.jsx', '.css', 'scss'],
alias: {
react: path.resolve('./node_modules/react'),
}
},
output: {
path: path.resolve(ROOT_PATH, 'dist'),
publicPath: '/',
filename: '[name].bundle.js',
chunkFilename: '[id].bundle.js'
},
};
It bundles fine but when I run the application I run into the error above. I can't tell if it's related to how i'm exporting my common components, but it it seems right. I read I should have a react alias in my app, which I do. I'm using yarn workspaces and not sure if that's related somehow.

Run the following command:
yarn why react
If the result shows that you have multiple versions of react:
Remove all local installations
Install a single version of React in the root workspace instead

this is probably a bug coming from yarn
issue:
https://github.com/yarnpkg/yarn/issues/8540
I did a workaround by:
exporting my common package into a new private github repo
create access token
https://docs.github.com/en/free-pro-team#latest/github/authenticating-to-github/creating-a-personal-access-token
in my package.json dependencies I added:
"common": "git+https://{accessToken}:x-oauth-basic#github.com/{user}/{repo}.git",

It happened to me when when migrating existing project to mono repo.
It was caused because I copied the lock files into the packages folders.
I've solved it by deleting any node_modules and any lock(yarn.lock and package-lock) from any package folder and then running yarn install on root directory.

WebPack importing react custom packages in another folder

I am enhancing a website with ReactJS.
My folder structure looks something like this:
_npm
node_modules
package.json
package-lock.json
webpack.config.js
_resources
js
react
reactapp1.js
reactapp2.js
components
FormDisplay.js
I want to import a custom reactjs package into the FormDisplay component.
When I enter:
import PlacesAutocomplete from 'react-places-autocomplete'
This doesn't work. But if I enter:
import PlacesAutocomplete from "./../../../_npm/node_modules/react-places-autocomplete";
This works. I understand why this is the case. I was wondering if there was a way that I can just enter:
import PlacesAutocomplete from 'react-places-autocomplete';
How do I make it work with just that line of code, without having to find the path to node_modules folder?
My webpack config:
const path = require("path");
const webpack = require("webpack");
const PATHS = {
app: path.join(__dirname, "../_resources/react/"),
build: path.join(__dirname, '../wordpress_site/wp-content/themes/custom_theme/assets/js/'),
};
module.exports = {
entry: {
reactapp1: path.join(PATHS.app, "reactapp1.js"),
reactapp2: path.join(PATHS.app, "reactapp2.js")
},
output: {
filename: "[name].bundle.js",
//path: path.join(__dirname, "dist")
path: PATHS.build
},
module:{
rules: [
{
test: /\.js?$/,
exclude: /(node_modules)/,
use: {
loader: "babel-loader",
options: {
presets: ["env", "react"],
plugins: ["transform-class-properties"]
}
}
}
]// rules array
}, // module
}

Have you tried using webpack's resolve-modules?
resolve: {
modules: ['_npm/node_modules']
}
Might work

Bundle JS files with webpack scripts?

I'm super new to webpack and I do not seem to find a way to bundle JS files as I did with Gulp in a very easy way. I've been searching a bit but didn't find any straight answer to it.
Right now I'm creating two minified files by using in my package.json file, but I would love to have a single one instead:
"scripts": {
"stand-alone": "concurrently 'webpack --config=webpack.config.js src/whatever.vue demos/build.min.js --output-library=whatever1' 'webpack --config=webpack.config.js src/whatever2.js demos/mixin.min.js --output-library=whatever2'",
},
Then my webpack.config.js looks like this:
const webpack = require('webpack');
module.exports = {
resolve: {
alias: {
'vue$': 'vue/dist/vue.js'
}
},
module: {
rules: [
{
test: /\.vue$/,
loader: 'vue-loader',
options: {
loaders: {
scss: 'vue-style-loader!css-loader!sass-loader',
js: 'babel-loader'
}
}
},
{
test: /\.js$/,
use: {
loader: 'babel-loader',
}
}
]
},
plugins: [
new webpack.optimize.UglifyJsPlugin({
compress: {
warnings: false,
drop_console: false,
}
})
],
};

I believe you are looking for entry points.
In your webpack.config.js module exports object:
Define the entry property:
entry: {
app: ['./path/to/file.js', './path/to/file2.js'],
},
Define the output property:
output: {
path: '/path/to/assets', // ex. '../../wwwroot/dist'
filename: '[name].js', // Substitutes [name] with the entry name, results in app.js
publicPath: '/'
},
Change your script to:
"scripts": {
"stand-alone": "webpack --config=webpack.config.js",
},
If you are using Vue + Webpack, I recommend that you take a look to vue-cli and generate a project using the webpack template. It is more advanced, but you can see the documentation and get an idea of what you are missing.
Run the following:
npm install -g vue-cli // install vue cli globally
vue init webpack my-project // create a sample project
If you want to generate multiple output files, you can have more than one entry point like so:
entry: {
app: ['./path/to/file.js', './path/to/file2.js'],
mixins: './path/to/mixins.js',
vendors: ['./path/to/vendor.js', './path/to/vendor2.js']
},
This will write to disk ./path/to/assets/app.js, ./path/to/assets/mixins.js, /path/to/assets/vendors.js.

Run Mocha specs from React app in a browser using Webpack and mocha-loader

I have a react App for which I'd like to run its mocha specs (unit-tests) in a browser. I found this SO post and tried to apply same idea to my project. I came up with the following webpack config file:
webpack.config.test.js
const nodeExternals = require('webpack-node-externals');
const path = require('path');
const host = 'localhost';
const port = '8084';
module.exports = {
target: 'web',
externals: [nodeExternals()],
entry: './specs/index.js',
output: {
filename: 'debug.bundle.js',
path: path.join(__dirname, 'tests'),
publicPath: `http://${host}:${port}/tests`,
},
devServer: {
host,
port,
},
module: {
rules: [
{
test: /\.js$/,
loaders: ['react-hot-loader', 'babel-loader'],
enforce: 'pre',
},
{
test: /.+Spec\.js$/,
loaders: ['mocha-loader'],
},
{
test: /(\.css|\.scss)$/,
loader: 'null-loader',
exclude: [
/build/,
],
},
{
test: /(\.jpg|\.jpeg|\.png|\.gif)$/,
loader: 'null-loader',
},
],
},
};
And, after starting the server with:
webpack-dev-server --config webpack.config.test.js
I get the following error in console:
I've read that the problem might be with webpack-node-externals but not really sure what's happening. Any ideas?

I think you will want to use webpack-node-externals only when you bundle files for backend (as described in plugin README). When you use it you forbid it to build all modules from node_modules folder.