Angular with .NET WebAPI validation, and single-point-of-truth

Question

Is there an approach that preserves the single-definition of validation, allows immediate client-side validation, and still provides the strength of server-side validation?

Answer 1

The approach I recommend is based on @Esteban Felix commented and I used similar strategy in Java/Bean Validation and JSON schema generator.

Annotate your Domain model using Validate Model Data Using DataAnnotations

Generate schema using JSON.net other useful links

Create a AutoValidate directive that goes on and decorate fields with AngularJS build in directives for form validation e.g. ngPattern and simple things like min/max. In my case I created a mapping from Java world to AngularJS directives and wherever I needed we created custom directives.