How to make a Symfony Callback validator Doctrine aware? - php

Question

As said in the title, I actually need to create a validation process with Symfony.
I'm using YAML file, everything is okay.
But in some cases, I need to check the database before saying that the data is validated.
I was searching in the Callback method, but it actually only allows me to basically check the values. I searched to make dependency injection, or even passing a defined service as a Callback, but it does not help too.
So the question, in short is: is it possible to achieve it? In which way?

Answer 1

With what #dragoste said in comments, I searched how to made it with my own constraint.
The solution is so to use a Custom Constraint. It is a bit messy to know what file to make and what to do, so here is what I have done.
To explain you what are my files, the goal was to validate a rent, not by how it is made but just check that there is no rent at the same moment. That's why I have to use a constraint with Doctrine inside it.
Creating the Validator folder inside the root of your bundle. Then, adding a Constraints folder inside the Validator folder.
Creating a file RentDatesConstraint.php in Validaor/Constraints folder.
Here is how it looks:
<?php
namespace ApiBundle\Validator\Constraints;
use ApiBundle\Validator\RentDatesValidator;
use Symfony\Component\Validator\Constraint;
class RentDatesConstraint extends Constraint
{
public $message = 'The beginning and ending date of the rent are not available for this vehicle.'; // note that you could use parameters inside it, by naming it with % to surround it
/**
* #inheritdoc
*/
public function validatedBy()
{
return RentDatesValidator::class; // this is the name of the class that will be triggered when you need to validate this constraint
}
/**
* #inheritdoc
*/
public function getTargets()
{
return self::CLASS_CONSTRAINT; // says that this constraints is a class constraint
}
}
Now you have created your own class constraint, you have to create your own validator.
Create a file RentDatesValidator.php in Validator folder.
<?php
namespace ApiBundle\Validator;
use Doctrine\Bundle\DoctrineBundle\Registry;
use Doctrine\Common\Collections\Collection;
use Symfony\Component\Validator\Constraint;
use Symfony\Component\Validator\ConstraintValidator;
class RentDatesValidator extends ConstraintValidator
{
/**
* #var Registry $doctrine
*/
private $doctrine;
/**
* RentDatesValidator constructor.
* #param Registry $_doctrine
*/
public function __construct(Registry $_doctrine)
{
$this
->setDoctrine($_doctrine)
;
}
/**
* #param Registry $_doctrine
* #return $this
*/
public function setDoctrine(Registry $_doctrine)
{
$this->doctrine = $_doctrine;
return $this;
}
/**
* #inheritdoc
* #param Rent $_value
*/
public function validate($_value, Constraint $_constraint)
{
//do your stuff here
if ($testFails) {
$this
->context
->buildViolation($_constraint->message) // here you can pass an array to set the parameters of the string, surrounded by %
->addViolation()
;
}
}
}
We are almost finished, we have to declare it as a service, so here we edit services.yml in Resources/config
services:
# [...]
validator.rent_dates:
class: ApiBundle\Validator\RentDatesValidator
tags:
- { name: validator.constraint_validator }
arguments: [ "#doctrine" ]
You can notice here that I passed #doctrine service, but you can actually pass any service you want, even many, as long as you are defining the RentDatesValidator class properly to accept those services in its constructor.
And now, all you have to do is to use this in your validation.
Here we edit Rent.yml in Resource/config/validation to add this only line:
ApiBundle\Entity\Rent:
constraints:
- ApiBundle\Validator\Constraints\RentDatesConstraint: ~
We are done! The validation will work when passing your object to the validator service.
You can notice that this is made with YAML, I personally prefer this way of doing things as it separate each parts (entity-definition, database schema, validation files, ...) but you can do it with annotation, XML or even pure PHP. It's up to you, so if you want to see more syntax, you can still go on the link to Symfony Documentation to know how to do this.