How to set environment variables in a cross-platform way?

Question

For Windows, my Node scripts should look like this:

"scripts": {
    "start-docs": "SET NODE_ENV=development&&babel-node ./docs/Server.js"
}

But on Linux there's no SET, so it would be like this:

"scripts": {
    "start-docs": "NODE_ENV=development&&babel-node ./docs/Server.js"
}

Is there a way to declare environment variables in a way that is consistent and cross-platform?

Answer 1

I recently came across the cross-env project. It's pretty straight-forward

{
  "scripts": {
    "build": "cross-env NODE_ENV=production webpack --config build/webpack.config.js"
  }
}

That will set the build environment variable to production regardless of the OS.

Answer 2

I would vote against setting this in package.json because environment variables should be set dependent on your environment while package.json is most likely the same for every environment (you commit it to your version control system, right?). Instead you should use something like dotenv if you are looking for a clean and generic solution.