How can I set response header on express.js assets

Question

I need to set CORS to be enabled on scripts served by express. How can I set the headers in these returned responses for public/assets?

Answer 1

This is so annoying.

Okay if anyone is still having issues or just doesn't want to add another library. All you have to do is place this middle ware line of code before your routes.

Cors Example

app.use((req, res, next) => {
    res.append('Access-Control-Allow-Origin', ['*']);
    res.append('Access-Control-Allow-Methods', 'GET,PUT,POST,DELETE');
    res.append('Access-Control-Allow-Headers', 'Content-Type');
    next();
});

// Express routes
app.get('/api/examples', (req, res)=> {...});

Answer 2

@klode's answer is right.

However, you are supposed to set another response header to make your header accessible to others.

---

Example:

First, you add 'page-size' in response header

response.set('page-size', 20);

Then, all you need to do is expose your header

response.set('Access-Control-Expose-Headers', 'page-size')