What is Joi validation and how do I use it?

What is Joi validation and how do I use it?

Joi is a powerful schema description language and data validator for JavaScript. It helps you validate objects, strings, numbers, and more.

Can you show me a simple example of how to validate an object using Joi?

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 result = schema.validate({ name: 'John', age: 25 });
console.log(result);

What happens if the validation fails?

If validation fails, Joi returns an error object that contains details about what went wrong, including which fields are invalid.

Can I customize the error messages?

Yes, you can customize error messages in Joi by using the messages method when defining your schema.