How to set NODE_ENV from package.json for react

As per the docs, we cannot override NODE_ENV, but there is a room to create our own custom variables starting with REACT_APP_. So i configured to look as below:

Reference: https://facebook.github.io/create-react-app/docs/adding-custom-environment-variables

"staging": "concurrently -k  \"npm:staging-server\" \"cross-env REACT_APP_ENVIRONMENT='staging' PORT=3003 react-scripts start\"",

And inside my UI application, I can fetch its value by consoling it like this: console.log('REACT_APP_ENVIRONMENT => ', process.env.REACT_APP_ENVIRONMENT);

I build the build with REACT_APP_STAGE and use it in my application as process.env.REACT_APP_STAGE.

"scripts": {
    "analyze": "source-map-explorer 'build/static/js/*.js'",
    "build-css": "node-sass-chokidar --include-path ./src --include-path ./node_modules src/ -o src/",
    "watch-css": "npm run build-css && node-sass-chokidar --include-path ./src --include-path ./node_modules src/ -o src/ --watch --recursive",
    "start-js": "react-scripts start",
    "start": "REACT_APP_STAGE=local npm-run-all -p watch-css start-js",
    "build": "npm run build-css && react-scripts build",
    "build-dev": "REACT_APP_STAGE=dev react-scripts build",
    "build-prod": "REACT_APP_STAGE=prod react-scripts build",
    "build-qa": "REACT_APP_STAGE=qa react-scripts build",
    "test": "react-scripts test --env=jsdom",
    "eject": "react-scripts eject"
  },