Set Up Multiple Environment Domains in React

To set up multiple domain names for your React application, you need to follow these steps:

1. Create a .env file in the root directory of your React application, which will be used to store domain names for different environments.
2. Define a variable in the .env file for each environment. For example, you can define a variable called REACT_APP_API_URL for the development environment and set it to the domain name for development. Similarly, you can define a variable called REACT_APP_API_URL for the production environment and set it to the domain name for production.
3. Development environment: REACT_APP_API_URL is set to http://dev.example.com
   Production environment: REACT_APP_API_URL is set to http://prod.example.com
4. In a React application’s code, you can access these environment variables using the process.env object. For example, you can use process.env.REACT_APP_API_URL in your code to fetch the domain for the current environment.
5. Store the API URL in the variable named apiUrl by accessing it from the environment variables using React.
6. It is essential to use the prefix REACT_APP_ in order to access these environment variables in a React application.
7. Based on your needs, configure different startup commands for different environments in the startup script (scripts section in the package.json file). For example, you can use the “react-scripts start” command to start the application in the development environment and specify the variables to be used in the .env.development file.
8. “Scripts section includes commands for starting the application in different environments using env-cmd and react-scripts.”
9. In the above example, we used the env-cmd library to load the environment variable file before starting the application.
10. When starting the application in different environments, use the corresponding startup command. For example, you can use the command npm run start:dev to start the application in a development environment.

This way, you can configure different domain names based on different environments, and use corresponding environment variables in your application. This allows your application to run in different environments and easily switch domain names as needed.