How can I implement custom error classes in my Express.js app?

How can I implement custom error classes in my Express.js app?

You can create custom error classes by extending the built-in Error class in JavaScript. Here's a simple example:

Can you show me a code snippet for that?

Sure! Here's a basic implementation:

class CustomError extends Error {
    constructor(message, statusCode) {
        super(message);
        this.statusCode = statusCode;
    }
}

module.exports = CustomError;

How do I use this CustomError class in my routes?

You can use it in your route handlers like this:

const CustomError = require('./path/to/CustomError');

app.get('/some-route', (req, res, next) => {
    const error = new CustomError('Not Found', 404);
    next(error);
});