childprocess

childprocess
=======

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[npm-image]: https://img.shields.io/npm/v/childprocess.svg?style=flat-square
[npm-url]: https://npmjs.org/package/childprocess
[travis-image]: https://img.shields.io/travis/node-modules/childprocess.svg?style=flat-square
[travis-url]: https://travis-ci.org/node-modules/childprocess
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[appveyor-url]: https://ci.appveyor.com/project/fengmk2/childprocess
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[cov-url]: https://codecov.io/github/node-modules/childprocess?branch=master
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[david-url]: https://david-dm.org/node-modules/childprocess
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[download-url]: https://npmjs.org/package/childprocess

Inject script into multiple process when using child_process.fork.

One of the use case is Multiple Process Code Coverage with [istanbul].

- cluster code coverage with istanbul

Install

``bash
$ npm i childprocess
`

Usage

`js
require('childprocess').inject(function(modulePath, args, opt) {
const execFile = 'path/to/istanbul';
const cwd = opt.cwd && process.cwd();
const execArgs = [
'cover',
'--root', cwd,
'--dir', path.join(cwd, './coverage'),
'--report', 'none',
'--print', 'none',
'--include-pid',
modulePath,
'--',
].concat(args);
return [execFile, execArgs, opt];
});
require('child_process').fork();
`

APIs

inject(cb) / inject(filepath)

Inject script when using child_process.fork.

The inject script is a function that running in sandbox in every process. that mean you can't use the variable out of the function.

The function should return an array that contains 3 arguments same as fork.

`js
childprocess.inject(function(modulePath, args, opt) {
return [modulePath, args, opt];
});
`

$3

Use child_process.fork` without injected script.

License

MIT

[istanbul]: https://github.com/gotwarlost/istanbul