Custom build script in Node.js

Category: Dev Toolbox 2020-02-06 Łukasz Nojek

For simple build tasks in Node.js I use a custom script. Let’s consider the following requirements:

Create the dist and dist/assets folders.
Concatenate several JavaScript files and save to dist/background-dist.js.
Copy assets/*.png files to dist/assets/.
Copy several other files.

Here is the source file:

const fs = require('fs');

function prepare() {
	if (!fs.existsSync('dist'))
		fs.mkdirSync('dist');
	if (!fs.existsSync('dist/assets'))
		fs.mkdirSync('dist/assets');
}

function js() {
	const files = [
		'lib/firebase-app.js',
		'lib/firebase-auth.js',
		'lib/firebase-firestore.js',
		'background.js'
	];

	let res = '';
	for (const file of files)
		res += fs.readFileSync(file, 'utf-8');

	fs.writeFileSync('dist/background-dist.js', res);
}

function misc() {
	for (const file of fs.readdirSync('assets/')) {
		if (file.endsWith('.png'))
			fs.copyFileSync('assets/' + file, 'dist/assets/' + file);
	}

	fs.copyFileSync('popup.html', 'dist/popup.html');
	fs.copyFileSync('popup.js', 'dist/popup.js');

	fs.copyFileSync('manifest.json', 'dist/manifest.json');
}


prepare(); // req #1
js();      // req #2
misc();    // req #3 & #4

Finally, add the script to package.json:

  ...
  "scripts": {
    "build": "node build.js"
  },

Łukasz Nojek – blog

Software development and architecture

Custom build script in Node.js

Category: Dev Toolbox 2020-02-06 Łukasz Nojek

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