* Returns static::DENY if any of the rules evaluated to static::DENY
* Returns static::ALLOW if at least one of the rules evaluated to
* static::ALLOW and none to static::DENY
* Otherwise returns NULL
*
*/
class ChainRequestPolicy implements ChainRequestPolicyInterface {
/**
* A list of policy rules to apply when this policy is evaluated.
*
* @var \Drupal\Core\PageCache\RequestPolicyInterface[]
*/
protected $rules = [];
/**
* {@inheritdoc}
*/
public function check(Request $request) {
$final_result = NULL;
foreach ($this->rules as $rule) {
$result = $rule->check($request);
if ($result === static::DENY) {
return $result;
}
elseif ($result === static::ALLOW) {
$final_result = $result;
}
elseif (isset($result)) {
throw new \UnexpectedValueException('Return value of RequestPolicyInterface::check() must be one of RequestPolicyInterface::ALLOW, RequestPolicyInterface::DENY or NULL');
}
}
return $final_result;
}
/**
* {@inheritdoc}
*/
public function addPolicy(RequestPolicyInterface $policy) {
$this->rules[] = $policy;
return $this;
}
}