How can I use Joi for data validation in my Node.js application?

How can I use Joi for data validation in my Node.js application?

You can use Joi by first installing it via npm. Then, you can define a schema for your data and validate it against that schema.

Can you show me a simple example of a Joi schema?

Sure! Here's a basic example:

const Joi = require('joi');

const schema = Joi.object({
  name: Joi.string().min(3).required(),
  age: Joi.number().integer().min(0).required()
});

const { error, value } = schema.validate({ name: 'John', age: 25 });

What happens if the validation fails?

If validation fails, Joi will return an error object that contains details about what went wrong, allowing you to handle it appropriately.

Can I customize the error messages?

Yes, you can customize error messages by using the .messages() method in your schema definition.