Oct 1, 2024 · Oct 1, 2024 · Oct 1, 2024 · Oct 1, 2024
diff --git a/security/voters.rst b/security/voters.rst
        abstract protected function voteOnAttribute(string $attribute, mixed $subject, TokenInterface $token): bool;
    }

 .. _how-to-use-the-voter-in-a-controller:

 .. tip::
 The Cacheable Voter Interface
 -----------------------------
 When Symfony calls the ``isGranted()`` method during runtime, it checks each voter
 until it meets the access decision strategy set by the configuration.
 While this generally works well, it can slow down performance in some cases.

 Imagine a backend displaying 20 items, each with 6 properties and 3 actions
 (like edit, show, delete). Checking permissions for all these requires 180 calls
 to each voter. With 5 voters, that's 900 calls.

 Usually, voters only need to focus on a specific permission (e.g., ``EDIT_BLOG_POST``)
 or object type (e.g., ``User``). This focus makes voters cacheable, so Symfony 5.4 introduces a
 :class:`Symfony\\Component\\Security\\Core\\Authorization\\Voter\\CacheableVoterInterface`

    namespace Symfony\Component\Security\Core\Authorization\Voter;

    interface CacheableVoterInterface extends VoterInterface
    {
        public function supportsAttribute(string $attribute): bool;

        // $subjectType is the value returned by get_class($subject) or get_debug_type($subject)
        public function supportsType(string $subjectType): bool;
    }

 If your voter returns false for these methods, it will cache this result,
 and your voter won't be called again for that attribute or type.

 If you extend from the abstract Voter class, you don't need to implement
 the interface directly - just override ``supportsAttribute()`` and/or ``supportsType()``.

 For instance, if your voter handles multiple object types but all permissions
 are prefixed with ``APPROVE_``, do this:

    namespace App\Security;

    use Symfony\Component\Security\Core\Authorization\Voter\Voter;

    class MyVoter extends Voter
    {
        public function supportsAttribute(string $attribute): bool
        {
            return str_starts_with($attribute, 'APPROVE_');
        }

        // ...
    }

 If your voter handles various permissions for a specific type, do this:

    namespace App\Security;

    use App\Entity\BlogPost;
    use Symfony\Component\Security\Core\Authorization\Voter\Voter;

    class MyVoter extends Voter
    {
        public function supportsType(string $subjectType): bool
        {
            // you can't use a simple BlogPost::class === $subjectType comparison
            // here because the given subject type could be the proxy class used
            // by Doctrine when creating the entity object
            return is_a($subjectType, BlogPost::class, true);
        }

        // ...
    }

    Checking each voter several times can be time consuming for applications
    that perform a lot of permission checks. To improve performance in those cases,
    you can make your voters implement the :class:`Symfony\\Component\\Security\\Core\\Authorization\\Voter\\CacheableVoterInterface`.
    This allows the access decision manager to remember the attribute and type
    of subject supported by the voter, to only call the needed voters each time.
 .. _how-to-use-the-voter-in-a-controller:

 Setup: Checking for Access in a Controller
 ------------------------------------------
Original file line number	Diff line number	Diff line change
Expand Up		@@ -48,15 +48,75 @@ which makes creating a voter even easier::
		abstract protected function voteOnAttribute(string $attribute, mixed $subject, TokenInterface $token): bool;
		}

		.. _how-to-use-the-voter-in-a-controller:

		.. tip::
		The Cacheable Voter Interface
michnovka marked this conversation as resolved. Show resolvedHide resolved
		-----------------------------
		When Symfony calls the ``isGranted()`` method during runtime, it checks each voter
		until it meets the access decision strategy set by the configuration.
		While this generally works well, it can slow down performance in some cases.

		Imagine a backend displaying 20 items, each with 6 properties and 3 actions
		(like edit, show, delete). Checking permissions for all these requires 180 calls
		to each voter. With 5 voters, that's 900 calls.

		Usually, voters only need to focus on a specific permission (e.g., ``EDIT_BLOG_POST``)
		or object type (e.g., ``User``). This focus makes voters cacheable, so Symfony 5.4 introduces a
		:class:`Symfony\\Component\\Security\\Core\\Authorization\\Voter\\CacheableVoterInterface`
michnovka marked this conversation as resolved. Show resolvedHide resolved

		namespace Symfony\Component\Security\Core\Authorization\Voter;

		interface CacheableVoterInterface extends VoterInterface
		{
		public function supportsAttribute(string $attribute): bool;

		// $subjectType is the value returned by get_class($subject) or get_debug_type($subject)
		public function supportsType(string $subjectType): bool;
		}

		If your voter returns false for these methods, it will cache this result,
		and your voter won't be called again for that attribute or type.

		If you extend from the abstract Voter class, you don't need to implement
		the interface directly - just override ``supportsAttribute()`` and/or ``supportsType()``.

		For instance, if your voter handles multiple object types but all permissions
		are prefixed with ``APPROVE_``, do this:

		namespace App\Security;

		use Symfony\Component\Security\Core\Authorization\Voter\Voter;

		class MyVoter extends Voter
		{
		public function supportsAttribute(string $attribute): bool
		{
		return str_starts_with($attribute, 'APPROVE_');
		}

		// ...
		}

		If your voter handles various permissions for a specific type, do this:

		namespace App\Security;

		use App\Entity\BlogPost;
		use Symfony\Component\Security\Core\Authorization\Voter\Voter;

		class MyVoter extends Voter
		{
		public function supportsType(string $subjectType): bool
		{
		// you can't use a simple BlogPost::class === $subjectType comparison
		// here because the given subject type could be the proxy class used
		// by Doctrine when creating the entity object
		return is_a($subjectType, BlogPost::class, true);
		}

		// ...
		}

		Checking each voter several times can be time consuming for applications
		that perform a lot of permission checks. To improve performance in those cases,
		you can make your voters implement the :class:`Symfony\\Component\\Security\\Core\\Authorization\\Voter\\CacheableVoterInterface`.
		This allows the access decision manager to remember the attribute and type
		of subject supported by the voter, to only call the needed voters each time.
		.. _how-to-use-the-voter-in-a-controller:

		Setup: Checking for Access in a Controller
		------------------------------------------
Expand Down