@types/yup

Schema Validation

This feature allows you to define a schema and validate an object against it. The schema can include various types and validation rules.

const yup = require('yup');

const schema = yup.object().shape({
  name: yup.string().required(),
  age: yup.number().required().positive().integer(),
});

schema.isValid({
  name: 'John Doe',
  age: 30
}).then(function(valid) {
  console.log(valid); // true
});

Asynchronous Validation

Yup supports asynchronous validation, which is useful for validating data that requires asynchronous operations, such as checking if an email is already in use.

const yup = require('yup');

const schema = yup.object().shape({
  email: yup.string().email().required(),
});

schema.validate({
  email: 'not-an-email'
}).catch(function(err) {
  console.log(err.errors); // ['email must be a valid email']
});

Custom Validation

You can define custom validation rules using the `test` method. This allows for more complex validation logic that is not covered by the built-in methods.

const yup = require('yup');

const schema = yup.object().shape({
  password: yup.string().required().min(8).test('is-strong', 'Password is not strong enough', value => {
    return /[A-Z]/.test(value) && /[0-9]/.test(value);
  })
});

schema.validate({
  password: 'weakpass'
}).catch(function(err) {
  console.log(err.errors); // ['Password is not strong enough']
});