class ChainRequestPolicy

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

Expanded class hierarchy of ChainRequestPolicy

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

View on git.drupalcode.org

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

Namespace

Drupal\Core\PageCache
View source 
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;
  }

}

Members

Title Modifiers Object type Summary Overriden Title
ChainRequestPolicy::$rules protected property A list of policy rules to apply when this policy is evaluated.
ChainRequestPolicy::addPolicy public function Add a policy to the list of policy rules. Overrides ChainRequestPolicyInterface::addPolicy
ChainRequestPolicy::check public function Determines whether delivery of a cached page should be attempted. Overrides RequestPolicyInterface::check
RequestPolicyInterface::ALLOW constant Allow delivery of cached pages.
RequestPolicyInterface::DENY constant Deny delivery of cached pages.

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