screeps-scripts/docs/in-depth/cookbook/environment-variables.md

Managing deploys with environment variables

Environment variables provide a more streamlined way to manage your build process. We can also use it to define "build toggles", or environment-based variables that will be injected into your scripts to be used during runtime.

Setting it up

Let's say that we want to set NODE_ENV to production for uploading to our main branch, and development for uploading to our Simulation branch. First we'll catch the environment variable and assign the compile target.

// rollup.config.js

const isProduction = process.env.NODE_ENV === 'production'

// use the `main` target from `screeps.json` in production mode
const cfg = isProduction ? 'main' : 'sim';

export default {
  // ...
  plugins: [
    // ...
    screeps({
      config: require("./screeps")[cfg],
      // if `NODE_ENV` is local, perform a dry run
      dryRun: process.env.NODE_ENV === 'local'
    })
  ]
}

Running a deploy

Then we'll change the build tasks on package.json to pass the environment variable before running the rollup command.

{
  "tasks": {
    "deploy-prod": "NODE_ENV=production rollup -c",
    "deploy-dev": "NODE_ENV=development rollup -c",
  }
}

Note: On Windows, setting the environment variables as defined above will not work. For a cross-platform solution to define environment variables, use cross-env.

npm install --save-dev cross-env

{
  "tasks": {
    "deploy-prod": "cross-env NODE_ENV=production rollup -c",
    "deploy-dev": "cross-env NODE_ENV=development rollup -c",
  }
}

Now let's give it a try! Run npm run deploy-dev or npm run deploy-prod and see if your code is uploaded properly.

Setting up build toggles

[TODO]