React Native Process Env Has Only Node_env

When you're working on React Native projects, understanding how the `process.env` variable behaves can be crucial. One common issue that many developers encounter is the case when `process.env` only has `NODE_ENV` available. In this article, we'll take a deep dive into this situation and explore why this might be happening, as well as how you can work around it.

So, let's start by clarifying what `process.env` is. In Node.js and React Native applications, `process.env` is an object that stores various environment variables. These variables can be accessed at runtime and are commonly used to configure the behavior of applications based on the environment they are running in.

In a typical setup, you might expect `process.env` to contain multiple key-value pairs representing different environment variables. However, there are cases where you might find that only `NODE_ENV` is available in the `process.env` object.

This situation usually occurs when you're running your React Native app without specifying additional environment variables explicitly. When you run the app without setting any additional environment variables, only the default `NODE_ENV` variable is automatically available in the `process.env` object.

If you need to access other environment variables in your React Native project, you can set them explicitly when running your app. One way to achieve this is by using tools like `react-native-config`, which allows you to define environment variables in a `.env` file and access them in your code.

To work around the issue of having only `NODE_ENV` available in `process.env`, you can follow these steps:

1. Install the `react-native-config` package in your project by running:

npm install @envy/react-native-config

2. Create a `.env` file in the root directory of your project and define your custom environment variables in the following format:

API_URL=https://api.example.com
API_KEY=your_api_key

3. Update your project's build scripts to use `react-native-config` to load the environment variables defined in the `.env` file. For example, you can modify your `package.json` scripts as follows:

"scripts": {
  "android": "npx react-native run-android",
  "ios": "npx react-native run-ios",
  "start": "npx react-native start",
  "build:android": "npx react-native run-android --variant=release",
  "build:ios": "npx react-native bundle --entry-file='index.js' --bundle-output='./ios/main.jsbundle' --dev=false --platform='ios' --assets-dest='./ios'",
  "postinstall": "npx react-native config"
}

4. Access your custom environment variables in your React Native code like this:

const apiUrl = process.env.API_URL;
const apiKey = process.env.API_KEY;

By following these steps and using `react-native-config` to manage your environment variables, you can ensure that you have access to all the necessary configuration options in your React Native project, not just `NODE_ENV`. This approach can help you streamline your development process and make your code more flexible and maintainable.