How to dump asserts for Entity/Document in Symfony2

kotoblog_53f028c2c1943.php

<?php
$user = new User();
/** @var \Symfony\Component\Validator\Mapping\ClassMetadataFactory $metadataFactory */
$metadataFactory = $this->get('validator.mapping.class_metadata_factory');
$metadata = $metadataFactory->getMetadataFor($user);
$constraints = [];

echo "Constraints:";

foreach ($metadata->properties as $property) {
    foreach ($property->constraints as $constraint) {
        $class = get_class($constraint);
        $arrayNamespace = explode("\\", $class);
        $class = $arrayNamespace[count($arrayNamespace) -1];
        if (isset($constraint->max)) {
            $constraints[$property->getName()][$class]['max'] = $constraint->max;
        }
        if (isset($constraint->min)) {
            $constraints[$property->getName()][$class]['min'] = $constraint->min;
        }
        if (isset($constraint->pattern)) {
            $constraints[$property->getName()][$class]['pattern'] = $constraint->pattern;
        }
        $constraints[$property->getName()][$class]['groups'] = $constraint->groups;
    }
}
echo json_encode($constraints); exit;