Runtime Package Generator

The main use of this plugin is to keep node dependencies separate from a server bundle at runtime. This might be for file size, security or obscure dependencies that do not play well with Webpacks loading mechanisms.

This Webpack plugin will allow you to generate a package.json dynamically for your build to automatically keep a specific set of modules that you want external or excluded from your bundle. It will let you define what dependencies to keep and generate a new package.json in your build folder to be used with npm for installing modules separately to your bundle(s).

Installation

  npm install runtime-package-generator-webpack-plugin --save-dev

Usage

The plugin must be used in conjunction with the nodeExternals feature, which will ignore a require (i.e. Webpack will not resolve it), like so:

  const nodeExternals = require('webpack-node-externals')
  const RuntimePackagePlugin = require('runtime-package-generator-webpack-plugin')
  const runtimeDependencies = ['dependency-1', 'dependency-2']

  {
    // ... config
    plugins: [
      new RuntimePackagePlugin({
        requiredAtRuntime: runtimeDependencies,

        // optional target directory. default: 'build/package.json'
        dest: 'build/server',

        // optional json format. These are defaults
        jsonFormat: {
          type: 'spaces',
          size: 2
        }
      })
    ],
    externals: [
      nodeExternals({
        whitelist: runtimeDependencies
      })
    ]
  }

You might wish to combine this with a postbuild task to keep everything automatic. This would cd into the target directory of your new package.json the plugin created and automatically run an npm install to get those separate node dependencies in there. This is out of the scope of what this plugin should deliver, hence it is recommended to do such a task like the below snippet.

  "prebuild": "rimraf build",
  "build": "NODE_ENV=production webpack --config webpack.config.js",
  "postbuild": "cd build/server && npm install"