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Understanding ENV

How to start PORT on an env variable

Install dotenv package

Install the dotenv package using npm. This package allows you to load environment variables from a file.

Terminal window
npm install dotenv

Create a .env File:

Create a file named .env in the root of your project. This file will contain your environment variables. Add a variable for the port, for example:

Terminal window
PORT=3000

Load Environment Variables in Your Express App:

In your main Express application file (e.g., app.js or index.js), load the environment variables using dotenv. Add the following lines at the top of your file:

require('dotenv').config();

Use the PORT Environment Variable:

const express = require('express');
const app = express();
const port = process.env.PORT || 3000;
// Rest of your Express app code...
app.listen(port, () => {
console.log(`Server is running on http://localhost:${port}`);
});

Run Your Express App:

Terminal window
node app.js