What are the best practices for error handling in Express?

What are the best practices for error handling in Express?

In Express, 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 between different types of errors by checking the error properties. For instance, you might want to handle validation errors differently from server errors.

How can I send a custom error response?

You can customize the response by setting the status code and sending a JSON object with error details. For example:

app.use((err, req, res, next) => {
  res.status(err.status || 500).json({ message: err.message });
});