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1 change: 1 addition & 0 deletions cookbook/map.rst.inc
Original file line number Diff line number Diff line change
Expand Up @@ -132,6 +132,7 @@
* :doc:`/cookbook/security/remember_me`
* :doc:`/cookbook/security/impersonating_user`
* :doc:`/cookbook/security/voters`
* :doc:`/cookbook/security/voters_data_permission`
* :doc:`/cookbook/security/acl`
* :doc:`/cookbook/security/acl_advanced`
* :doc:`/cookbook/security/force_https`
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2 changes: 1 addition & 1 deletion cookbook/security/acl.rst
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Expand Up @@ -14,7 +14,7 @@ the ACL system comes in.
Using ACL's isn't trivial, and for simpler use cases, it may be overkill.
If your permission logic could be described by just writing some code (e.g.
to check if a Blog is owned by the current User), then consider using
:doc:`voters </cookbook/security/voters>`. A voter is passed the object
:doc:`voters </cookbook/security/voters_data_permission>`. A voter is passed the object
being voted on, which you can use to make complex decisions and effectively
implement your own ACL. Enforcing authorization (e.g. the ``isGranted``
part) will look similar to what you see in this entry, but your voter
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1 change: 1 addition & 0 deletions cookbook/security/index.rst
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Expand Up @@ -8,6 +8,7 @@ Security
remember_me
impersonating_user
voters
voters_data_permission
acl
acl_advanced
force_https
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26 changes: 26 additions & 0 deletions cookbook/security/voter_interface.rst.inc
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@@ -0,0 +1,26 @@
.. code-block:: php

interface VoterInterface
{
public function supportsAttribute($attribute);
public function supportsClass($class);
public function vote(TokenInterface $token, object, array $attributes);
}

The :method:`Symfony\\Component\\Security\\Core\\Authorization\\Voter\\VoterInterface::supportsAttribute`
method is used to check if the voter supports the given user attribute (i.e: a role, an acl, etc.).

The :method:`Symfony\\Component\\Security\\Core\\Authorization\\Voter\\VoterInterface::supportsClass`
method is used to check if the voter supports the current user token class.

The :method:`Symfony\\Component\\Security\\Core\\Authorization\\Voter\\VoterInterface::vote`
method must implement the business logic that verifies whether or not the
user is granted access. This method must return one of the following values:

* ``VoterInterface::ACCESS_GRANTED``: The user is allowed to access the
application
* ``VoterInterface::ACCESS_ABSTAIN``: The voter cannot decide if the user
is granted or not
* ``VoterInterface::ACCESS_DENIED``: The user is not allowed to access
the application

23 changes: 1 addition & 22 deletions cookbook/security/voters.rst
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Expand Up @@ -21,28 +21,7 @@ A custom voter must implement
:class:`Symfony\\Component\\Security\\Core\\Authorization\\Voter\\VoterInterface`,
which requires the following three methods:

.. code-block:: php

interface VoterInterface
{
public function supportsAttribute($attribute);
public function supportsClass($class);
public function vote(TokenInterface $token, $object, array $attributes);
}

The ``supportsAttribute()`` method is used to check if the voter supports
the given user attribute (i.e: a role, an ACL, etc.).

The ``supportsClass()`` method is used to check if the voter supports the
class of the object whose access is being checked (doesn't apply to this entry).

The ``vote()`` method must implement the business logic that verifies whether
or not the user is granted access. This method must return one of the following
values:

* ``VoterInterface::ACCESS_GRANTED``: The authorization will be granted by this voter;
* ``VoterInterface::ACCESS_ABSTAIN``: The voter cannot decide if authorization should be granted;
* ``VoterInterface::ACCESS_DENIED``: The authorization will be denied by this voter.
.. include:: /cookbook/security/voter_interface.rst.inc

In this example, you'll check if the user's IP address matches against a list of
blacklisted addresses and "something" will be the application. If the user's IP is blacklisted, you'll return
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210 changes: 210 additions & 0 deletions cookbook/security/voters_data_permission.rst
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@@ -0,0 +1,210 @@
.. index::
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This new document needs to be referenced in /cookbook/map.rst and /cookbook/security/index.rst.

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I added them right under the voter article.

single: Security; Data Permission Voters

How to Use Voters to Check User Permissions
===========================================

In Symfony2 you can check the permission to access data by using the
:doc:`ACL module </cookbook/security/acl>`, which is a bit overwhelming
for many applications. A much easier solution is to work with custom voters,
which are like simple conditional statements. Voters can also be used to
check for permission to a part or even of the whole application:
":doc:`/cookbook/security/voters`".

.. tip::

Have a look at the
:doc:`authorization </components/security/authorization>`
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I'd move chapter behind the doc ref:

.. tip::

    Have a look at the
    :doc:`authorization </components/security/authorization>`
    chapter for a better understanding on voters.

chapter for a better understanding on voters.

How Symfony Uses Voters
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How Symfony uses Voters

-----------------------

In order to use voters, you have to understand how Symfony works with them.
In general, all registered custom voters will be called every time you ask
Symfony about permissions (ACL). You can use one of three different
approaches on how to handle the feedback from all voters: affirmative,
consensus and unanimous. For more information have a look at
":ref:`the section about access decision managers <components-security-access-decision-manager>`".

The Voter Interface
-------------------

A custom voter must implement
:class:`Symfony\\Component\\Security\\Core\\Authorization\\Voter\\VoterInterface`,
which has this structure:

.. include:: /cookbook/security/voter_interface.rst.inc

In this example, it'll check if the user will have access to a specific
object according to your custom conditions (e.g. they must be the owner of
the object). If the condition fails, you'll return
``VoterInterface::ACCESS_DENIED``, otherwise you'll return
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you -> it?

``VoterInterface::ACCESS_GRANTED``. In case the responsibility for this decision
does not belong to this voter, it will return ``VoterInterface::ACCESS_ABSTAIN``.

Creating the Custom Voter
-------------------------

You could implement your Voter to check permission for the view and edit action like the following::

// src/Acme/DemoBundle/Security/Authorization/Voter/PostVoter.php
namespace Acme\DemoBundle\Security\Authorization\Voter;

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use Acme\DemoBundle\Entity\Post

(see below)

use Symfony\Component\Security\Core\Exception\InvalidArgumentException;
use Symfony\Component\DependencyInjection\ContainerInterface;
use Symfony\Component\Security\Core\Authorization\Voter\VoterInterface;
use Symfony\Component\Security\Core\Authentication\Token\TokenInterface;
use Symfony\Component\Security\Core\User\UserInterface;
use Acme\DemoBundle\Entity\Post;

class PostVoter implements VoterInterface
{
const VIEW = 'view';
const EDIT = 'edit';

public function supportsAttribute($attribute)
{
return in_array($attribute, array(
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I would have used constants like in built-in voters.

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would you also want to use the constant within the controller to check for?

e.g.

if (false === $this->get('security.context')->isGranted(PostVoter::VIEW, $post)) {
    throw new AccessDeniedException('Unauthorised access!');
}

self::VIEW,
self::EDIT,
));
}

public function supportsClass($obj)
{
return $obj instanceof Post;
}

/**
* @var \Acme\DemoBundle\Entity\Post $post
*/
public function vote(TokenInterface $token, $post, array $attributes)
{
// check if class of this object is supported by this voter
if (!$this->supportsClass($post)) {
return VoterInterface::ACCESS_ABSTAIN;
}

// check if voter is used correct, only allow one attribute for a check
if(1 !== count($attributes) || !is_string($attributes[0])) {
throw new InvalidArgumentException(
'Only one attribute is allowed for VIEW or EDIT'
);
}

// set the attribute to check against
$attribute = $attributes[0];

// get current logged in user
$user = $token->getUser();

// check if the given attribute is covered by this voter
if (!$this->supportsAttribute($attribute)) {
return VoterInterface::ACCESS_ABSTAIN;
}
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this implementation looks weird to me: you are abstaining even if some of the attributes are supported. None of the core voters are behaving this way (most of the time, you are checking a single attribute so it is not a common case though)

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You are right, I am going to allow one Attribute only.


// check if given user is instance of user interface
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remove comment?

if (!$user instanceof UserInterface) {
return VoterInterface::ACCESS_DENIED;
}

switch($attribute) {
case 'view':
// the data object could have for e.g. a method isPrivate()
// which checks the Boolean attribute $private
if (!$post->isPrivate()) {
return VoterInterface::ACCESS_GRANTED;
}
break;

case 'edit':
// we assume that our data object has a method getOwner() to
// get the current owner user entity for this data object
if ($user->getId() === $post->getOwner()->getId()) {
return VoterInterface::ACCESS_GRANTED;
}
break;
}

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remove this line break and you did not even use the container 👎

}
}

That's it! The voter is done. The next step is to inject the voter into
the security layer.

Declaring the Voter as a Service
--------------------------------

To inject the voter into the security layer, you must declare it as a service
and tag it as a ``security.voter``:

.. configuration-block::

.. code-block:: yaml

# src/Acme/DemoBundle/Resources/config/services.yml
services:
security.access.post_voter:
class: Acme\DemoBundle\Security\Authorization\Voter\PostVoter
public: false
tags:
- { name: security.voter }

.. code-block:: xml

<!-- src/Acme/DemoBundle/Resources/config/services.xml -->
<?xml version="1.0" encoding="UTF-8" ?>
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add <!-- src/Acme/DemoBundle/Resources/config/services.xml --> above this line

<container xmlns="http://symfony.com/schema/dic/services"
xsi:schemaLocation="http://symfony.com/schema/dic/services
http://symfony.com/schema/dic/services/services-1.0.xsd">
<services>
<service id="security.access.post_document_voter"
class="Acme\DemoBundle\Security\Authorization\Voter\PostVoter"
public="false">
<tag name="security.voter" />
</service>
</services>
</container>

.. code-block:: php

// src/Acme/DemoBundle/Resources/config/services.php
$container
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add // src/Acme/DemoBundle/Resources/config/services.php above this line

->register(
'security.access.post_document_voter',
'Acme\DemoBundle\Security\Authorization\Voter\PostVoter'
)
->addTag('security.voter')
;

How to Use the Voter in a Controller
------------------------------------

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missing some text

The registered voter will then always be asked as soon as the method ``isGranted()``
from the security context is called.

.. code-block:: php

// src/Acme/DemoBundle/Controller/PostController.php
namespace Acme\DemoBundle\Controller;

use Symfony\Bundle\FrameworkBundle\Controller\Controller;
use Symfony\Component\HttpFoundation\Response;
use Symfony\Component\Security\Core\Exception\AccessDeniedException;

class PostController extends Controller
{
public function showAction()
{
// get a Post instance
$post = ...;

// keep in mind, this will call all registered security voters
if (false === $this->get('security.context')->isGranted('view', $post)) {
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It appears that $post object should be recover before this check. (by a find($id) or with ParamConverter feature)

throw new AccessDeniedException('Unauthorised access!');
}

return new Response('<h1>'.$post->getName().'</h1>');
}
}