spawn-require

user-land --require flag equivalent that can handle forked processes

Node >= 4.0.0 provides a --require flag that allows you to register require hooks like babel-register, and coffee-script/register from the command line, but it has a few drawbacks:

1. It does not work on older versions of Node ('0.12' or before), which is problematic if you want to test your module on all LTS versions of Node.

2. It is propagated to child processes which use child_process.fork, but not those that use child_process.exec or child_process.spawn.

spawn-require solves both the above problems. It slows down forking quite a bit compared to the native Node implementations, so you should only use it if you actually need 1 or 2 above.

Install

$ npm install --save spawn-require

CLI

$ spawn-require babel-register babel-polyfill coffee-script/register -- node my-module.js

Registers Babel and CoffeeScript require hooks before launching my-module.js. If my-module.js spawns additional processes, the require hooks will be loaded in those spawned processes as well.

Note the -- separator. Everything before is a require hook, everything after is considered the program args.

API

const spawnRequire = require('spawn-require');
 
const unwrap = spawnRequire(['babel-register', 'babel-polyfill', 'coffee/register']);
//=> unwrap can be called later to undo the wrapping

spawnRegister(modulePaths)

Wraps child_process so spawned children will always require the specified modules before executing.

modulePaths

Type: array of strings

An list of modules that should be required before executing any forked processes (you may want to resolve them all to absolute paths).

License

MIT © James Talmage