class ChainRequestPolicy in Drupal 10

Implements a compound request policy.

When evaluating the compound policy, all of the contained rules are applied to the request. The overall result is computed according to the following rules:

<ol> <li>Returns static::DENY if any of the rules evaluated to static::DENY</li> <li>Returns static::ALLOW if at least one of the rules evaluated to static::ALLOW and none to static::DENY</li> <li>Otherwise returns NULL</li> </ol>

Hierarchy

• class \Drupal\Core\PageCache\ChainRequestPolicy implements \Drupal\Core\PageCache\ChainRequestPolicyInterface

2 files declare their use of ChainRequestPolicy

ChainRequestPolicyTest.php in core/tests/Drupal/Tests/Core/PageCache/ChainRequestPolicyTest.php

DefaultRequestPolicy.php in core/modules/dynamic_page_cache/src/PageCache/RequestPolicy/DefaultRequestPolicy.php

File

core/lib/Drupal/Core/PageCache/ChainRequestPolicy.php, line 21

Namespace

Drupal\Core\PageCache

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;
  }

}