Symfony2 - Custom validator and dependancy injection

Question

I am trying to use dependancy injection for a custom validator, in order to be able to use the entityManager.

I followed the Symfony Example: Dependency Injection, but I am allways getting this error message:

FatalErrorException: Error: Class 'isdoi' not found in /home/milos/workspace/merrin3/vendor/symfony/symfony/src/Symfony/Bundle/FrameworkBundle/Validator/ConstraintValidatorFactory.php line 68

Here are my classes:

1. The IsDOI class:

    <?php
    namespace Merrin\MainBundle\Validator\Constraints;
    use Symfony\Component\Validator\Constraint;

    /**
     * @Annotation
    */
    class IsDOI extends Constraint
    {
    public $message_publisher_DOI = 'The Publisher DOI abbreviation does not correspond to the DOI you filled in !';
    public $message_journal_DOI = 'No journal found with the DOI you filled in !';
    public $journal;
    public $doiAbbreviation;

     public function validatedBy() {
            return "isdoi";
        }

        public function getTargets()
        {
            return self::CLASS_CONSTRAINT;
        }
    }

2. The IsDOIValidator class:

<?php

namespace Merrin\MainBundle\Validator\Constraints;

use Doctrine\ORM\EntityManager;
use Symfony\Component\Validator\Constraint;
use Symfony\Component\Validator\ConstraintValidator;
use Symfony\Component\DependencyInjection\ContainerBuilder;

class IsDOIValidator extends ConstraintValidator
{
    private $entityManager;

    public function __construct(EntityManager $entityManager)
    {
    $this->entityManager = $entityManager;
    }

    public function validate($value, Constraint $constraint)
    {       
        $em_mdpipub = $this->entityManager('mdpipub');
        //Do some tests here...

    }
}

3. Service:

merrin.main.validator.isdoi:
    class:  Merrin\MainBundle\Validator\Constraints\IsDOIValidator
    arguments: 
        entityManager: "@doctrine.orm.entity_manager"

Where am I wrong? Thank you for your help.

Answer 1

You have wrong service file, when You add tags and alias you could use "isdoi" name

merrin.main.validator.isdoi:
    class:  Merrin\MainBundle\Validator\Constraints\IsDOIValidator
    arguments: 
        entityManager: "@doctrine.orm.entity_manager"
    tags:
        - { name: validator.constraint_validator, alias: isdoi }

Answer 2

You're telling Symfony2 that the validator class for your constraint is isdoi (validateBy method). However, your validator is IsDOIValidator.

You must use :

public function validateBy()
{
    return "IsDOIValidator";
}

However, if your Constraint class name is IsDOI, Symfony will automatically look for IsDOIValidator as a ConstraintValidator. The default behavior for validateBy is to append "Validator" to the constraint name, and look for the class with this name. So if you do not overload validateBy, Symfony2 will automatically search for IsDOIValidator.