How to read environment variables in Node.js

In Node.js, you can read environmental variables using the process.env object. This object provides access to the user environment, including environment variables. Here's a simple example of how you can read environmental variables in Node.js:

// Accessing a specific environment variable
const apiKey = process.env.API_KEY;

if (apiKey) {
  console.log('API Key:', apiKey);
} else {
  console.error('API Key not found in environmental variables.');
}

When running your Node.js application, you can set environmental variables in the terminal or script before starting the application. For example:

# Setting an environmental variable in Linux/macOS
export API_KEY=your_api_key

# Setting an environmental variable in Windows (PowerShell)
$env:API_KEY = "your_api_key"

Then, when you run your Node.js script, it can access the environmental variable using process.env.API_KEY.

Keep in mind the following:

1. Security Considerations:
   • Avoid hardcoding sensitive information directly in your code. Instead, use environmental variables to store sensitive data like API keys, database passwords, etc.
   • Be cautious about exposing sensitive information unintentionally.
2. Default Values:
   • It's a good practice to provide default values or check if the environmental variable exists before using it to avoid potential issues.
3. Environment-specific Configuration:
   • Environmental variables are useful for managing configuration settings in different environments (development, testing, production, etc.).

4. External Configuration:

   • Tools like dotenv can be used to load environmental variables from a .env file during development. Install it using npm install dotenv, and then include the following line at the beginning of your script:

      

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     require('dotenv').config();
     

     Create a .env file in your project directory with key-value pairs:

      

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     API_KEY=your_api_key
     

     Now, you can access these variables using process.env as usual.

Remember to handle environmental variables with care, especially when dealing with sensitive information, and follow security best practices.

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