symfony/symfony — pull request #3199 by blogsh (2012-01-27 15:03:39+00:00)
Title: [Validator] Added GroupSequenceProvider

Bug fix: no
Feature addition: yes
Backwards compatibility break: no
Symfony2 tests pass: ![](https://secure.travis-ci.org/blogsh/symfony.png?branch=dynamic_group_sequence)

As discussed in #3114 I implemented the "GroupSequenceProvider" pattern for the validator component. It allows the user to select certain validation groups based on the current state of an object. Here is an example:

/**
* @Assert\GroupSequenceProvider("UserGroupSequnceProvider")
*/
class User
{
/**
* @Assert\NotBlank(groups={"Premium"})
*/
public function getAddress();

public function hasPremiumSubscription();
}

class UserGroupSequenceProvider implements GroupSequenceProviderInterface
{
public function getValidationGroups($user)
{
if ($user->hasPremiumSubscription()) {
return array('User', 'Premium');
} else {
return array('User');
}
}
}

With this patch there are two mechanisms to define the group sequence now. Either you can use @GroupSequence to define a static order of validation groups or you can use @GroupSequenceProvider to create dynamic validation group arrays.
The ClassMetadata therefore has methods now which implement quite similar things. The question is whether it would make sense to interpret the static group sequence as a special case and create something like a DefaultGroupSequenceProvider or StaticGroupSequenceProvider which is assigned by default. This would cause a BC break inside the validator component.