Question
Answer and Explanation
To run an Express.js application in Ubuntu, you'll need to have Node.js and npm (Node Package Manager) installed. Here's a step-by-step guide:
1. Install Node.js and npm:
- First, update your package list:
sudo apt update
- Then, install Node.js and npm:
sudo apt install nodejs npm
- Verify the installation by checking the versions:
node -v
npm -v
2. Create an Express.js Application:
- If you don't have an existing Express.js application, create a new directory for your project:
mkdir my-express-app
cd my-express-app
- Initialize a new npm project:
npm init -y
- Install Express.js:
npm install express
- Create a file named app.js (or any name you prefer) and add the following basic Express.js code:
const express = require('express');
const app = express();
const port = 3000;
app.get('/', (req, res) => {
res.send('Hello World!');
});
app.listen(port, () => {
console.log(`Example app listening at http://localhost:${port}`);
});
3. Run the Express.js Application:
- In your project directory, run the application using Node.js:
node app.js
- You should see the message "Example app listening at http://localhost:3000" in your terminal.
4. Access the Application:
- Open your web browser and go to http://localhost:3000. You should see "Hello World!" displayed.
5. Using a Process Manager (PM2):
- For production environments, it's recommended to use a process manager like PM2 to keep your application running even if it crashes or the server restarts.
- Install PM2 globally:
sudo npm install pm2 -g
- Start your application with PM2:
pm2 start app.js
- To manage your application, you can use PM2 commands like pm2 stop app, pm2 restart app, and pm2 list.
By following these steps, you can successfully run your Express.js application on Ubuntu. Remember to adjust the port and application code as needed for your specific project.