Symfony validator with dependencies - php

Question

I want to validate an object with constraint annotations, and use dependencies (entityManager) at the validator.
The validator does not work, if it has dependencies (eg. entityManager) in the constructor.
I followed the docs, but it does not work:
https://symfony.com/doc/current/validation/custom_constraint.html#constraint-validators-with-dependencies
"ClassNotFoundException
Attempted to load class "validator_question_exists" from the global namespace.
Did you forget a "use" statement?"
I try to validate the 'Question' object like this (maybe here is the problem):
$validator = Validation::createValidatorBuilder()
->enableAnnotationMapping()
->getValidator()
;
$question = new Question();
$errors = $validator->validate($question);
Question (the object to validate)
/** #App\Validator\Constraint\Question\QuestionExists() */
class QuestionReadInput{
....
}
services.yaml
services:
validator.unique.question_exists:
class: App\Validator\Constraint\Question\QuestionExistsValidator
tags:
- { name: validator.constraint_validator, alias: validator_question_exists}
Constraint
namespace App\Validator\Constraint\Question;
use Symfony\Component\Validator\Constraint;
/**
* #Annotation
*/
class QuestionExists extends Constraint
{
public $message;
public function getTargets()
{
return self::CLASS_CONSTRAINT;
}
public function validatedBy()
{
//if i delete this function, symfony cant autowire the entitymanager to the validator
//this throws an error, wants to make a new validator_question_exists(), which not exists, because its a service alias, the docs said it should be okay
return 'validator_question_exists';
}
}
Validator
class QuestionExistsValidator extends ConstraintValidator
{
private $entityManager;
public function __construct(EntityManagerInterface $entityManager)
{
$this->entityManager = $entityManager;
}
public function validate($value, Constraint $constraint)
{
die('I dont see this message...');
}
debug:container
Information for Service "validator.unique.question_exists"
---------------- -------------------------------------------------------------------
Option Value
---------------- -------------------------------------------------------------------
Service ID validator.unique.question_exists
Class App\Validator\Constraint\Question\QuestionExistsValidator
Tags validator.constraint_validator (alias: validator_question_exists)
validator.constraint_validator
Public no
Synthetic no
Lazy no
Shared yes
Abstract no
Autowired yes
Autoconfigured yes

Answer 1

If you are declaring the service yourself, then you should also be adding it's arguments:
services:
validator.unique.question_exists:
class: App\Validator\Constraint\Question\QuestionExistsValidator
arguments: ['#doctrine.orm.entity_manager']
tags:
- { name: validator.constraint_validator }
Other than that it should work without any tag aliases or validatedBy method.
Sidenote: for quite a while now in Symfony it's recommended to name (id) your services by the class names, that way auto-wiring could handle your service, and you wouldn't need the class parameter, i.e.:
services:
App\Validator\Constraint\Question\QuestionExistsValidator:
arguments: ['#doctrine.orm.entity_manager']
tags:
- { name: validator.constraint_validator }

Answer 2

I just used the default symfony Validator, as #xabbuh mentioned, and it worked.
__construct(ValidatorInterface $validator){
$question = new Question();
$errors = $validator->validate($question);
}
I should have not create my own validator with Validaton::createValidatorBuilder.
It does not matter if you use this config:
App\Validator\Constraint\Question\QuestionExistsValidator:
tags: ['validator.constraint_validator']
with no validatedBy()
or that:
validator.unique.question_exists:
class: App\Validator\Constraint\Question\QuestionExistsValidator
tags:
- { name: validator.constraint_validator, alias: validator_question_exists}
with:
public function validatedBy() {
return 'validator_question_exists';
}