How do I use Express.js for my web application?

How do I use Express.js for my web application?

To use Express.js, first install it via npm with npm install express. Then, create a basic server.

Can you show me a simple example of setting up a server?

Sure! Here's a basic example:

const express = require('express');
const app = express();

app.get('/', (req, res) => {
  res.send('Hello World!');
});

app.listen(3000, () => {
  console.log('Server is running on http://localhost:3000');
});

What are some common middleware functions I can use?

Common middleware includes body-parser for parsing request bodies, morgan for logging, and cors for enabling CORS.

How do I handle errors in Express?

You can handle errors by defining an error-handling middleware function. Here's an example:

app.use((err, req, res, next) => {
  console.error(err.stack);
  res.status(500).send('Something broke!');
});