What is async middleware in Node.js?

What is async middleware in Node.js?

Async middleware in Node.js allows you to handle asynchronous operations in your middleware functions, making it easier to manage requests.

Can you give me an example of async middleware?

Sure! Here's a simple example:

const asyncMiddleware = fn => (req, res, next) => {
    Promise.resolve(fn(req, res, next)).catch(next);
};

app.get('/data', asyncMiddleware(async (req, res) => {
    const data = await fetchData();
    res.json(data);
}));

What happens if an error occurs in async middleware?

If an error occurs, it will be caught by the catch(next) part, which will pass the error to the next error-handling middleware.

Is async/await the only way to handle async operations in middleware?

No, you can also use Promises or callbacks, but async/await provides a cleaner and more readable syntax.