Validation is a very critical and recurrent task in web applications development.

Data entered in forms needs to be validated.

Data also needs to be validated when is received from mobile apps, javascript apps or other external systems.

Drupal 8 introduced a new Entity Validation API that has been moved out of form API providing a new way to validate entities that is based on symfony validator component.

With live practical examples in this session you will learn : 

 1. How to create a validation constraint plugin in drupal 8.

 2. How to perform clean validations in a drupal 8 web application using defined constraints.

 3. How to practically use symfony validator to validate nested and complex entities. 

 4. How to perform tests on your constraints.