How to stop npm script running in background automatically

Question

Im using npm scripts, I have some of them that should run in parallel. I've got something like this:

...
scripts: {
   "a": "taskA &",
   "preb": "npm run a",
   "b": "taskB"
}
...

This is fine! But I'd like to kill automatically taskA running the background after taskB has finished.

How can I do that? Thanks!

Answer 1

Using the concurrently package looks like a less tricky & painful way. This avoids detached processes (&) alltogether. And promises to be more cross-plattform, too.

npm install concurrently --save

and then in package.json

"runBoth": "concurrently \"npm run taskA\" \"npm run taskB\"",

Tested (under Ubuntu 16.04, npm 5.6), also see here.

Answer 2

The npm-run-all package may be what you're looking for:

$ npm install --save npm-run-all

Then in your package.json file:

"scripts": {
    "runA": "taskA",
    "runB": "taskB",
    "runBoth": "npm-run-all -p runA runB"
}

(-p runs them in parallel, use -s for sequential.)