What are the best practices for error handling in Express.js?

What are the best practices for error handling in Express.js?

In Express.js, it's important to use middleware for error handling. You should define an error-handling middleware function that takes four arguments: err, req, res, and next. This allows you to centralize your error handling.

Can you give me an example of an 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 response.

What about handling different types of errors?

You can differentiate errors by checking the error type or properties. For instance, you might want to handle validation errors differently from server errors. You can use conditionals in your middleware to customize the response based on the error type.

Is it a good idea to expose error details to the client?

Generally, it's not recommended to expose detailed error information to clients in production, as it can reveal sensitive information. Instead, log the details on the server and send a generic error message to the client.