How to set environment variables in package.json file

In this tutorial, we are going to learn about how to set the environment variables within a package.json file.

Setting environment variables

1. First, we need to install a new package called cross-env which helps us to set environment variables across all platforms (like windows, mac, linux, etc).

npm install cross-env

2. Open your package.json file and set the environment variables inside script command like this.

"scripts": {
    "start": "cross-env REACT_APP=development react-scripts start",
    "build": "cross-env REACT_APP=production  react-scripts build",
},

Now, you can access the environment variables inside your app using process.env.variable-name.

if(process.env.REACT_APP === "development"){   console.log('hello dev mode');
     // do something
}