What is error handling in Express.js?

What is error handling in Express.js?

Error handling in Express.js refers to the process of managing errors that occur during the execution of your application. It allows you to catch errors and respond appropriately, ensuring a better user experience.

How can I implement error handling in my Express app?

You can implement error handling in Express by using middleware functions. You can define an error-handling middleware that takes four arguments: err, req, res, and next. This middleware can be used to log errors and send a response to the client.

Can you show me an example of error-handling middleware?

Sure! Here's a simple example:

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

This middleware logs the error stack and sends a 500 status response.

What types of errors should I handle?

You should handle both synchronous and asynchronous errors, such as validation errors, database connection issues, and unexpected exceptions. It's important to provide meaningful feedback to users.