Develop Reference

Combine, Minify, and convert to ES5 with WebPack and Babel

I have a project that works perfect and was written in TS, I had to convert it to plain JS and it works for the most part. The issue where I am struggling is removing the default WebPack loader after the files have been combined and minified, WebPack includes a loader to the final output even thought I do not need a loader since all the files are combined into one large file.
+ filea.js
+ fileb.js
+ filec.js
+ filed.js
-> output bundle.js
I have read a few articles/posts that recommend manually creating a config file providing the name of each of the files that will combined and minified, this may work OK but the problem is that the project I am working on is broken into small chunks (modules) so that tools such WebPack can be smart enough and know when a file should be added as a dependency in the final output.
I know we can combine and minify multiple individual JS files but when it comes to exporting a single file it seems like the task is trivial With TS but in the vanilla JS world there is little or no information about the subject.

I don't understand something, do you want to have one big file or small individual modules (chunks)?
An example of small modules:
module.exports = {  
entry: {    
app: './src/app.js',
admin: './src/admin.js',
contact: './src/contact.js'  
}
};
Another method is one main module and it contains all smaller modules.
module.exports = {  
entry: {    
app: './src/app.js'  
}
};
You can also use something like lazy loading. Then the modules (chunks) will be dynamically loaded only when needed. lazy-loading
Here is an example of using several entries webpack-boilerplate.

Sounds like you have a project with several JS files and you want to use webpack to bundle all of them and minify the result.
Webpack was built for this.
You'll need to add a build step in your package.json like this:
"scripts": {
"build": "webpack --config prod.config.js"
}
Then you'll need to create a webpack.config.js with a module.exports block that has an entry point and rules to include in your project. The following should be a minimal setup that can get your started:
const path = require('path');
module.exports = {
entry: "./your/path/to/src",
output: {
path: path.resolve(__dirname, "dist"),
filename: "bundle.js"
},
module: {},
plugins: [
new MinifyPlugin(minifyOpts, pluginOpts)
]
}
You can add modules that perform additional code transpilation for files that matcha a certain regex. You can also use a plugin to perform minification such as babel-minify-webpack-plugin as documented here https://webpack.js.org/plugins/babel-minify-webpack-plugin/. (Note you will need to add this dependency.)
The full webpack configuration can be found here: https://webpack.js.org/configuration/

Webpack to "ignore" some entrypoints

I'm using Webpack to build my front end components.
I have some React components which need classic webpack bundling, though I also have some vanilla JS files.
Those latter files are independent, so they won't get imported from React files. From my understanding, they need to be defined as entrypoints, so that Webpack reads and processes them. So far, so good.
The trouble is that I'd like Webpack to load them with Babel, and that's all, only give me back the JS file processed through Babel, I'm not interested in a bundle for these files.
Is it possible to do that? Only get the result of the babel loader, and not produce a bundle for some entrypoints?
Maybe I shouldn't use Webpack at all for these files?
Or maybe I should just set these bundles as 'library' so that I can reach them from the HTML pages?
What do you think guys?
Thanks by advance ;)

depends on how easy it is to find these files. I have a project that has similar requirement. What I have done is:
1/ put the vanilla js file in third_party/lib/
2/ import/require them in my current project
3/ set up my webpack.config.js as follows:
module.export = {
module: {
rules: [{
test : /.js$/,
exclude : /node_modules|third_party/,
loaders : ['babel-loader' /* other loaders? */],
},{
test : /third_party.*?\.js$/,
use: [{
loader : 'babel-loader' // or other loaders
},{
loader: 'file-loader'
options: {
name : '[path][name].[ext]',
outputPath : 'dist/third_party'
}
}]
}]
}
}
oh, you will need to npm i --save-dev file-loader
edit: I should clarify that this will bundle the vanilla js file as separate files to your main bundle, so you will have to import them by script tags yourself in your html file. (or if they were worker files, called by your script)

How to make Webpack use project's "node_modules" in js scripts located outside the project folder?

I have Node.js project and the following structure of folders:
lib
awesome-formatter.js
FrontEndApp
prettify.js
node_modules
awesome-parser
BackEndApp
...
I use awesome-parser module and awesome-formatter.js library in prettify.js script like this:
require('awesome-parser')
require('../lib/awesome-formatter.js')
awesome-formatter.js, in turns, should use awesome-parser too:
require('awesome-parser')
My FrontEndApp has been configured to use Webpack, and I'm trying to run it in dev mode using npm run dev command. However, I got the following error:
ERROR Failed to compile with 1 errors
These dependencies were not found:
* awesome-parser in /home/user/dev/lib/awesome-formatter.js
I don't want to move awesome-formatter.js inside the FrontEndApp because I also use it in BackEndApp project (and probably in some other projects) and I don't want to create separate "node_modules" in "lib" for it just not to duplicate installed modules on disk.
So, my question is, how to make Webpack use project's "node_modules" in js scripts located outside the project folder?
P.S. Of course there are workarounds like symlinks or making a full-featured module (with package.json etc.) from lib/awesome-fromatter and installing it into FrontEndApp/node_modules, but is there a direct way to solve this problem?

I've found a solution: resolve.modules sould be added to Webpack configuration file.
module.exports = {
...
resolve: {
...
modules: [
'node_modules',
resolve('node_modules')
]
},
...
}
This means that Webpack is searching modules in 'node_modules' as a relative subfolder (and it's the usual behavior), and at the absolute path to the project's 'node_modules' as well: resolve('node_modules'), so that scripts in folders outside the project (like lib in my structure) can find and use it.

webpack: transpiling file so out put is next to the source file

I am using webpack to turn my ts in js. I want the js files to be placed at the same location as their ts sources. right now I am 'cheating' by having many entry points. the entry points are the path to the file.
here is the snippet of my config
entry: {
'path/to/my/file':'path/to/my/file.ts',
'other/path/to/other/file':'other/path/to/other/file.ts'
},
output: {
path: rootFolder,
publicPath: outputFolderName + '/',
filename: '[name].js'
}
this currently works. I was wondering if there was a cleaner way to do this. Some way of not depending on having the name of the entry point be the path so that the entry points are more flexible.

You are using wrong tool for this job. Webpack is bundler, it is designed to bundle many files into single package.
What you want to do is to compile Typescript into Javascript. Use typescript compiler for that. Just use/run tsc.
Just make sure outDir in tsconfig.json is equal . or absent at all.
You might need to install it globally for ease of use
npm install -g typescript

How to bundle a library with webpack?

I want to create a frontend library.
Therefore I want to use webpack. I especially like the css and image loader.
However I can only require non-JS files if I am using webpack.
Because I am building a library, I cannot garanty that the user of my library will too.
Is there I way to bundle everything into a UMD module to publish it?
I tried using multiple entry points, however I cannot require the module then.

You can find good guide for creating libraries in Webpack 2.0 documentation site. That's why I use ver 2 syntax in webpack.config.js for this example.
Here is a Github repo with an example library.
It builds all files from src/ (js, png and css) into one JS bundle which could be simply required as an umd module.
for that we need to specify the follow settings in webpack.config.js:
output: {
path: './dist',
filename: 'libpack.js',
library: 'libpack',
libraryTarget:'umd'
},
and package.json should have:
"main": "dist/libpack.js",
Note that you need to use appropriate loaders to pack everything in one file. e.g. base64-image-loader instead of file-loader

The comment written by #OlegPro is very helpful. I suggest every one to read this article for explanation of how these stuff work
http://krasimirtsonev.com/blog/article/javascript-library-starter-using-webpack-es6
You need the following for sure if you want to be able to import the bundle file in your project
output: {
path: path.resolve(__dirname, myLibrary),
filename: 'bundle.js',
library: "myLibrary", // Important
libraryTarget: 'umd', // Important
umdNamedDefine: true // Important
},