What is a Yup schema and how do I use it?

What is a Yup schema and how do I use it?

A Yup schema is a JavaScript object schema builder for value parsing and validation. You can use it to validate forms.

Can you show me an example of a Yup schema?

Sure! Here's a simple example:

import * as Yup from 'yup';

const schema = Yup.object().shape({
  name: Yup.string().required('Name is required'),
  age: Yup.number().positive().integer().required('Age is required'),
});

This schema validates that 'name' is a required string and 'age' is a required positive integer.

How do I validate data against this schema?

You can use the validate method provided by Yup. For example:

schema.validate({ name: 'John', age: 30 })
  .then(function(value) {
    console.log('Valid!', value);
  })
  .catch(function(err) {
    console.log('Validation error:', err.errors);
  });

What happens if the validation fails?

If validation fails, Yup will throw a validation error, and you can catch it to handle the error messages accordingly.