What are some examples of CORS in web development?

What are some examples of CORS in web development?

CORS, or Cross-Origin Resource Sharing, allows web applications to request resources from different origins. For example, if your frontend is hosted on 'example.com' and it needs to access an API on 'api.example.com', CORS headers must be set on the API to allow this.

Can you give me a specific code example?

Sure! Here's a simple example using Express.js:

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

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

app.get('/data', (req, res) => {
  res.json({ message: 'This is CORS-enabled for all origins!' });
});

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

What if I want to restrict access to certain domains?

You can specify allowed origins like this:

app.use(cors({ origin: 'https://specific-domain.com' }));
``` This will only allow requests from 'specific-domain.com'.