How to automatically zip files with Node.js and npm

Question

Is there a way to automatically zip certain files at the build time with Node.js and npm?

For example, I have a project, that file structure looks like this:

Project/
--lib/
--node_modules/
--test/
--index.js
--package.json

I want to be able to zip lib folder, certain modules from node_modules and index.js into some zip archive to upload it on the AWS Lambda, for example. I do not need test folder or test Node.js modules (mocha and chai) to be zipped. I have even created a bash script for generating zip file, but is there a way to automatically execute this script, when 'npm install' is called?

This should be a standard problem and it should have a standard solution, but I was unable to discover such.

UPDATE

thanks to michael, decided to use gulp. This is my script, in case some one else will need it for AWS Lambda:

var gulp = require('gulp');
var clean = require('gulp-clean');
var zip = require('gulp-zip');
var merge = require('merge-stream');

gulp.task('clean', function () {
    var build = gulp.src('build', {read: false})
        .pipe(clean());
    var dist = gulp.src('dist', {read: false})
        .pipe(clean());

    return merge(build, dist);
});

gulp.task('build', function() {
    var index = gulp.src('index.js')
        .pipe(gulp.dest('build'));
    var lib = gulp.src('lib/**')
        .pipe(gulp.dest('build/lib'));
    var async = gulp.src('node_modules/async/**')
        .pipe(gulp.dest('build/node_modules/async'));
    var collections = gulp.src('node_modules/collections/**')
        .pipe(gulp.dest('build/node_modules/collections'));
    var underscore = gulp.src('node_modules/underscore/**')
        .pipe(gulp.dest('build/node_modules/underscore'));
    var util = gulp.src('node_modules/util/**')
        .pipe(gulp.dest('build/node_modules/util'));
    var xml2js = gulp.src('node_modules/xml2js/**')
        .pipe(gulp.dest('build/node_modules/xml2js'));

    return merge(index, lib, async, collections, underscore, util, xml2js);
});

gulp.task('zip', ['build'], function() {
    return gulp.src('build/*')
        .pipe(zip('archive.zip'))
        .pipe(gulp.dest('dist'));
});

gulp.task('default', ['zip']);

Answer 1

I realize this answer comes years too late for the original poster. But I had virtually the same question about packaging up a Lambda function, so for posterity, here's a solution that doesn't require any additional devDependencies (like gulp or grunt) and just uses npm pack along with the following package.json (but does assume you have sed and zip available to you):

{
  "name": "my-lambda",
  "version": "1.0.0",
  "scripts": {
    "postpack": "tarball=$(npm list --depth 0 | sed 's/@/-/g; s/ .*/.tgz/g; 1q;'); tar -tf $tarball | sed 's/^package\\///' | zip -@r package; rm $tarball"
  },
  "files": [
    "/index.js", 
    "/lib"
  ],
  "dependencies": {
    "async": "*",
    "collections": "*",
    "underscore": "*",
    "util": "*",
    "xml2js": "*"
  },
  "bundledDependencies": [
    "async",
    "collections",
    "underscore",
    "util",
    "xml2js"
  ],
  "devDependencies": {
    "chai": "*",
    "mocha": "*"
  }
}

Given the above package.json, calling npm pack will produce a package.zip file that contains:

index.js
lib/
node_modules/
├── async/
├── collections/
├── underscore/
├── util/
└── xml2js/

The files array is a whitelist of what to include. Here, it's just index.js and the lib directory.

However, npm will also automatically include package.json, README (and variants like README.md, CHANGELOG (and its variants), and LICENSE (and the alternative spelling LICENCE) unless you explicitly exclude them (e.g. with .npmignore).

The bundledDependencies array specifies what packages to bundle. In this case, it's all the dependencies but none of the devDependencies.

Finally, the postpack script is run after npm pack because npm pack generates a tarball, but we need to generate a zip for AWS Lambda.

A more detailed explanation of what the postpack script is doing is available at https://hackernoon.com/package-lambda-functions-the-easy-way-with-npm-e38fc14613ba (and is also the source of the general approach).