How do I use CORS in Node.js?

How do I use CORS in Node.js?

To use CORS in Node.js, you can use the 'cors' middleware package. Would you like to see a code example?

Yes, please show me a code example.

Sure! First, install the package using npm install cors. Then, you can use it like this:

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

const app = express();
app.use(cors()); // Enable CORS for all routes

app.get('/api/data', (req, res) => {
    res.json({ message: 'Hello World!' });
});

app.listen(3000, () => {
    console.log('Server running on port 3000');
});

What if I want to restrict CORS to specific origins?

You can specify allowed origins by passing an options object to the cors() function. For example:

app.use(cors({ origin: 'https://example.com' }));