Lab Exercise: Returning Data Based on the ENV Variable

🎯 Objectives

Learn how to:

• Configure applications to return data based on environment variables.
• Manage different environments effectively in full-stack development.

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📚 Prerequisites

Before you begin, ensure you:

• Are familiar with JavaScript.
• Understand the basics of environment variables.

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🚀 Steps

1. Install dotenv

Install the dotenv package to manage environment variables:

yarn add dotenv

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2. Require dotenv in Your File

Add the following line at the top of your main file to load the environment variables:

require('dotenv').config();

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3. Define the Environment Variables

Create a .env file in your project directory and define your variables:

IS_ADMIN=true

You can modify the value to true or false depending on your requirements.

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4. Access Environment Variables

Use process.env to access your variables anywhere in your application. Here's an example:

const isAdmin = process.env.IS_ADMIN === 'true';

if (isAdmin) {
  console.log("Admin privileges granted.");
} else {
  console.log("Access restricted. Admin only.");
}

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5. Return Different Data

Conditionally return different data based on the value of the environment variable. Example:

const express = require('express');
require('dotenv').config();

const app = express();

app.get('/', (req, res) => {
  if (process.env.IS_ADMIN === 'true') {
    res.send({ message: "Welcome, Admin!", data: ["Admin Data 1", "Admin Data 2"] });
  } else {
    res.send({ message: "Welcome, User!", data: ["User Data 1", "User Data 2"] });
  }
});

app.listen(3000, () => console.log("Server is running on port 3000."));

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🏁 Outcome

By completing this exercise, you will:

• Understand how to manipulate application behavior using environment variables.
• Learn to handle different environments securely and efficiently.

🎉 Congratulations! You’ve mastered a crucial skill for full-stack development! 💼🔐