README

Attribute-based validation, compiled to a reflection-free validator — the same build-time pattern as genai/dto / genai/sql-mapper.

Define a form

use GenAI\Validation\Attribute\Validate;
use GenAI\Validation\Attribute\NotBlank;
use GenAI\Validation\Attribute\Email;
use GenAI\Validation\Attribute\Length;
use GenAI\Validation\Attribute\Matches;

#[Validate]
class SignupForm
{
    #[NotBlank]                 public $name;
    #[NotBlank] #[Email]        public $email;
    #[Length(min: 6)]           public $password;
    #[Matches('password')]      public $passwordConfirm;
}

The #[...] lines are build-only (comments on PHP 5.3).

Public or private fields. Public properties are read directly. A private/ protected field is read through a getXxx()/isXxx() getter (auto-detected at compile; a private field without one is a build error) — same approach as #[Dto]. Note the runtime still has to populate the form, so a private field also needs a setter or constructor; public props are the least ceremony.

Use it

// bind() populates declared fields from the request (public prop set directly,
// private via its setXxx() — where the form can normalize), then validate().
$form   = $validator->bind(new SignupForm(), $request->getParsedBody());
$errors = $validator->validate($form);   // array('email' => 'Please enter a valid email address.')
if (!$errors) {
    // valid — use $form->getEmail(), etc.
}

bind() only touches declared fields (no mass-assignment of stray request keys) and is reflection-free (it uses the same compiled field map as validate()). Put trimming/normalization in the form's setters and it runs automatically on bind. Inject GenAI\Validation\Validator — it's auto-wired (the package's bundle provides the bean as the compiled Cache\Validation). One first message per field.

Constraints

All except #[NotBlank] pass an empty value, so combine #[NotBlank] #[Email] to both require and format-check. Every constraint takes an optional message: to override the default.

How it compiles

ValidationProcessor reads each #[Validate] class's property constraints (matched via the Constraint base + IS_INSTANCEOF) and bakes a rule table into Cache\Validation extends GenAI\Validation\Validator. At runtime the Validator reads the form's public props and walks that table with a type switch — no reflection. Cache\Validation is always generated (empty when no forms), so the bean always resolves.