Zend Acl—当Acl规则返回false时,断言是否允许访问特权?


Zend Acl - is it possible for an assertion to allow access to a privilege when the acl rules return false?

默认情况下,即使acl规则允许,在断言中返回false也会拒绝访问。我想做的是另一种方式-即在acl规则拒绝访问时,在断言中返回true以允许访问。

例如:

class TestAssert implements Zend_Acl_Assert_Interface
{
    public function assert(Zend_Acl $acl, Zend_Acl_Role_Interface $role = null, Zend_Acl_Resource_Interface $resource = null,
                           $privilege = null)
    {
        return true;
    }
}
$acl = new Zend_Acl;
$acl->addResource('page');
$acl->addRole('user');
$acl->allow('user', 'page', 'read', new TestAssert);
$acl->isAllowed('user', 'page', 'write');

上面的isAllowed()将返回false,因为我所询问的特权在acl规则中是不允许的,因此它没有得到断言。

我想要的可能吗?

我想这样做的原因是,用户可能对所有页面都有一定的权限,然后对他们创建的页面有不同的权限集-当查询权限时,我希望能够判断页面是否是他们的,如果是,应用规则为"own-page"而不是"page"。显然,在实际应用中,传递的是user和page对象,而不是字符串。

UPDATE:我已经成功地通过子类化Zend_Acl来做我想做的。

该类允许为特定的角色和资源组合添加回调。当isAllowed()被调用时,回调函数(如果存在)将被运行。它被传入与断言相同的参数(以及parent::isAllowed()的结果)。这个回调函数的返回值是从isAllowed()返回的,除非它为null,在这种情况下使用正常的返回值。

class Acl extends Zend_Acl
{
    protected $_callbacks = array();
    /**
     * Takes into account the callback to determine whether the role is allowed access
     * 
     * @param Zend_Acl_Role_Interface $role
     * @param Zend_Acl_Resource_Interface $resource
     * @param string $privilege
     * @return bool
     */
    public function isAllowed($role = null, $resource = null, $privilege = null)
    {
        $result = parent::isAllowed($role, $resource, $privilege);
        $role = $this->getRole($role)->getRoleId();
        $resource = $this->get($resource)->getResourceId();
        if(isset($this->_callbacks[$role][$resource]))
        {           
            $callbackResult = call_user_func($this->_callbacks[$role][$resource], $this, $role, $resource, $privilege, $result);
        }
        return isset($callbackResult) ? $callbackResult : $result;
    }
    /**
     * Add a callback for a specific role and resource combination.
     * If the callback returns a value, this is used as the return value for isAllowed().
     * Otherwise, if the callback returns null, the normal result of isAllowed() will be used.
     * 
     * @param Zend_Acl_Role_Interface $role
     * @param Zend_Acl_Resource_Interface $resource
     * @param callback $callback 
     */
    public function addCallback($role, $resource, $callback)
    {
        $role = $this->getRole($role)->getRoleId();
        $resource = $this->get($resource)->getResourceId();
        $this->_callbacks[$role][$resource] = $callback;
    }
}

用法:

$acl = new Acl;
$acl->addResource('page');
$acl->addRole('user');
$acl->addCallback('user', 'page', function($acl, $role, $resource, $privilege, $result)
{
    return true;
});

$acl->allow('user', 'page', array('read'));
$acl->isAllowed('user', 'page', 'edit'); //returns true even though 'edit' is not allowed.

听起来你想要一些类似以下的内容:

class WriteAssert implements Zend_Acl_Assert_Interface
{
    public function assert(Zend_Acl $acl,
                           Zend_Acl_Role_Interface $role = null,
                           Zend_Acl_Resource_Interface $resource = null,
                           $privilege = null)
    {
        // return whether the user owns the page
    }
}
$acl = new Zend_Acl;
$acl->addResource('page');
$acl->addRole('user');
$acl->allow('user', 'page', 'read');
$acl->allow('user', 'page', 'write', new WriteAssert);
$acl->isAllowed('user', 'page', 'write');

这里,您希望用户能够读取任何页面,但只能写入自己的页面。