diff core/lib/Drupal/Core/Entity/EntityAccessControlHandler.php @ 0:4c8ae668cc8c

Initial import (non-working)

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/core/lib/Drupal/Core/Entity/EntityAccessControlHandler.php	Wed Nov 29 16:09:58 2017 +0000
@@ -0,0 +1,381 @@
+<?php
+
+namespace Drupal\Core\Entity;
+
+use Drupal\Core\Access\AccessResult;
+use Drupal\Core\Field\FieldItemListInterface;
+use Drupal\Core\Field\FieldDefinitionInterface;
+use Drupal\Core\Language\LanguageInterface;
+use Drupal\Core\Session\AccountInterface;
+
+/**
+ * Defines a default implementation for entity access control handler.
+ */
+class EntityAccessControlHandler extends EntityHandlerBase implements EntityAccessControlHandlerInterface {
+
+  /**
+   * Stores calculated access check results.
+   *
+   * @var array
+   */
+  protected $accessCache = [];
+
+  /**
+   * The entity type ID of the access control handler instance.
+   *
+   * @var string
+   */
+  protected $entityTypeId;
+
+  /**
+   * Information about the entity type.
+   *
+   * @var \Drupal\Core\Entity\EntityTypeInterface
+   */
+  protected $entityType;
+
+  /**
+   * Allows to grant access to just the labels.
+   *
+   * By default, the "view label" operation falls back to "view". Set this to
+   * TRUE to allow returning different access when just listing entity labels.
+   *
+   * @var bool
+   */
+  protected $viewLabelOperation = FALSE;
+
+  /**
+   * Constructs an access control handler instance.
+   *
+   * @param \Drupal\Core\Entity\EntityTypeInterface $entity_type
+   *   The entity type definition.
+   */
+  public function __construct(EntityTypeInterface $entity_type) {
+    $this->entityTypeId = $entity_type->id();
+    $this->entityType = $entity_type;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function access(EntityInterface $entity, $operation, AccountInterface $account = NULL, $return_as_object = FALSE) {
+    $account = $this->prepareUser($account);
+    $langcode = $entity->language()->getId();
+
+    if ($operation === 'view label' && $this->viewLabelOperation == FALSE) {
+      $operation = 'view';
+    }
+
+    // If an entity does not have a UUID, either from not being set or from not
+    // having them, use the 'entity type:ID' pattern as the cache $cid.
+    $cid = $entity->uuid() ?: $entity->getEntityTypeId() . ':' . $entity->id();
+
+    // If the entity is revisionable, then append the revision ID to allow
+    // individual revisions to have specific access control and be cached
+    // separately.
+    if ($entity instanceof RevisionableInterface) {
+      /** @var $entity \Drupal\Core\Entity\RevisionableInterface */
+      $cid .= ':' . $entity->getRevisionId();
+    }
+
+    if (($return = $this->getCache($cid, $operation, $langcode, $account)) !== NULL) {
+      // Cache hit, no work necessary.
+      return $return_as_object ? $return : $return->isAllowed();
+    }
+
+    // Invoke hook_entity_access() and hook_ENTITY_TYPE_access(). Hook results
+    // take precedence over overridden implementations of
+    // EntityAccessControlHandler::checkAccess(). Entities that have checks that
+    // need to be done before the hook is invoked should do so by overriding
+    // this method.
+
+    // We grant access to the entity if both of these conditions are met:
+    // - No modules say to deny access.
+    // - At least one module says to grant access.
+    $access = array_merge(
+      $this->moduleHandler()->invokeAll('entity_access', [$entity, $operation, $account]),
+      $this->moduleHandler()->invokeAll($entity->getEntityTypeId() . '_access', [$entity, $operation, $account])
+    );
+
+    $return = $this->processAccessHookResults($access);
+
+    // Also execute the default access check except when the access result is
+    // already forbidden, as in that case, it can not be anything else.
+    if (!$return->isForbidden()) {
+      $return = $return->orIf($this->checkAccess($entity, $operation, $account));
+    }
+    $result = $this->setCache($return, $cid, $operation, $langcode, $account);
+    return $return_as_object ? $result : $result->isAllowed();
+  }
+
+  /**
+   * We grant access to the entity if both of these conditions are met:
+   * - No modules say to deny access.
+   * - At least one module says to grant access.
+   *
+   * @param \Drupal\Core\Access\AccessResultInterface[] $access
+   *   An array of access results of the fired access hook.
+   *
+   * @return \Drupal\Core\Access\AccessResultInterface
+   *   The combined result of the various access checks' results. All their
+   *   cacheability metadata is merged as well.
+   *
+   * @see \Drupal\Core\Access\AccessResultInterface::orIf()
+   */
+  protected function processAccessHookResults(array $access) {
+    // No results means no opinion.
+    if (empty($access)) {
+      return AccessResult::neutral();
+    }
+
+    /** @var \Drupal\Core\Access\AccessResultInterface $result */
+    $result = array_shift($access);
+    foreach ($access as $other) {
+      $result = $result->orIf($other);
+    }
+    return $result;
+  }
+
+  /**
+   * Performs access checks.
+   *
+   * This method is supposed to be overwritten by extending classes that
+   * do their own custom access checking.
+   *
+   * @param \Drupal\Core\Entity\EntityInterface $entity
+   *   The entity for which to check access.
+   * @param string $operation
+   *   The entity operation. Usually one of 'view', 'view label', 'update' or
+   *   'delete'.
+   * @param \Drupal\Core\Session\AccountInterface $account
+   *   The user for which to check access.
+   *
+   * @return \Drupal\Core\Access\AccessResultInterface
+   *   The access result.
+   */
+  protected function checkAccess(EntityInterface $entity, $operation, AccountInterface $account) {
+    if ($operation == 'delete' && $entity->isNew()) {
+      return AccessResult::forbidden()->addCacheableDependency($entity);
+    }
+    if ($admin_permission = $this->entityType->getAdminPermission()) {
+      return AccessResult::allowedIfHasPermission($account, $this->entityType->getAdminPermission());
+    }
+    else {
+      // No opinion.
+      return AccessResult::neutral();
+    }
+  }
+
+  /**
+   * Tries to retrieve a previously cached access value from the static cache.
+   *
+   * @param string $cid
+   *   Unique string identifier for the entity/operation, for example the
+   *   entity UUID or a custom string.
+   * @param string $operation
+   *   The entity operation. Usually one of 'view', 'update', 'create' or
+   *   'delete'.
+   * @param string $langcode
+   *   The language code for which to check access.
+   * @param \Drupal\Core\Session\AccountInterface $account
+   *   The user for which to check access.
+   *
+   * @return \Drupal\Core\Access\AccessResultInterface|null
+   *   The cached AccessResult, or NULL if there is no record for the given
+   *   user, operation, langcode and entity in the cache.
+   */
+  protected function getCache($cid, $operation, $langcode, AccountInterface $account) {
+    // Return from cache if a value has been set for it previously.
+    if (isset($this->accessCache[$account->id()][$cid][$langcode][$operation])) {
+      return $this->accessCache[$account->id()][$cid][$langcode][$operation];
+    }
+  }
+
+  /**
+   * Statically caches whether the given user has access.
+   *
+   * @param \Drupal\Core\Access\AccessResultInterface $access
+   *   The access result.
+   * @param string $cid
+   *   Unique string identifier for the entity/operation, for example the
+   *   entity UUID or a custom string.
+   * @param string $operation
+   *   The entity operation. Usually one of 'view', 'update', 'create' or
+   *   'delete'.
+   * @param string $langcode
+   *   The language code for which to check access.
+   * @param \Drupal\Core\Session\AccountInterface $account
+   *   The user for which to check access.
+   *
+   * @return \Drupal\Core\Access\AccessResultInterface
+   *   Whether the user has access, plus cacheability metadata.
+   */
+  protected function setCache($access, $cid, $operation, $langcode, AccountInterface $account) {
+    // Save the given value in the static cache and directly return it.
+    return $this->accessCache[$account->id()][$cid][$langcode][$operation] = $access;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function resetCache() {
+    $this->accessCache = [];
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function createAccess($entity_bundle = NULL, AccountInterface $account = NULL, array $context = [], $return_as_object = FALSE) {
+    $account = $this->prepareUser($account);
+    $context += [
+      'entity_type_id' => $this->entityTypeId,
+      'langcode' => LanguageInterface::LANGCODE_DEFAULT,
+    ];
+
+    $cid = $entity_bundle ? 'create:' . $entity_bundle : 'create';
+    if (($access = $this->getCache($cid, 'create', $context['langcode'], $account)) !== NULL) {
+      // Cache hit, no work necessary.
+      return $return_as_object ? $access : $access->isAllowed();
+    }
+
+    // Invoke hook_entity_create_access() and hook_ENTITY_TYPE_create_access().
+    // Hook results take precedence over overridden implementations of
+    // EntityAccessControlHandler::checkCreateAccess(). Entities that have
+    // checks that need to be done before the hook is invoked should do so by
+    // overriding this method.
+
+    // We grant access to the entity if both of these conditions are met:
+    // - No modules say to deny access.
+    // - At least one module says to grant access.
+    $access = array_merge(
+      $this->moduleHandler()->invokeAll('entity_create_access', [$account, $context, $entity_bundle]),
+      $this->moduleHandler()->invokeAll($this->entityTypeId . '_create_access', [$account, $context, $entity_bundle])
+    );
+
+    $return = $this->processAccessHookResults($access);
+
+    // Also execute the default access check except when the access result is
+    // already forbidden, as in that case, it can not be anything else.
+    if (!$return->isForbidden()) {
+      $return = $return->orIf($this->checkCreateAccess($account, $context, $entity_bundle));
+    }
+    $result = $this->setCache($return, $cid, 'create', $context['langcode'], $account);
+    return $return_as_object ? $result : $result->isAllowed();
+  }
+
+  /**
+   * Performs create access checks.
+   *
+   * This method is supposed to be overwritten by extending classes that
+   * do their own custom access checking.
+   *
+   * @param \Drupal\Core\Session\AccountInterface $account
+   *   The user for which to check access.
+   * @param array $context
+   *   An array of key-value pairs to pass additional context when needed.
+   * @param string|null $entity_bundle
+   *   (optional) The bundle of the entity. Required if the entity supports
+   *   bundles, defaults to NULL otherwise.
+   *
+   * @return \Drupal\Core\Access\AccessResultInterface
+   *   The access result.
+   */
+  protected function checkCreateAccess(AccountInterface $account, array $context, $entity_bundle = NULL) {
+    if ($admin_permission = $this->entityType->getAdminPermission()) {
+      return AccessResult::allowedIfHasPermission($account, $admin_permission);
+    }
+    else {
+      // No opinion.
+      return AccessResult::neutral();
+    }
+  }
+
+  /**
+   * Loads the current account object, if it does not exist yet.
+   *
+   * @param \Drupal\Core\Session\AccountInterface $account
+   *   The account interface instance.
+   *
+   * @return \Drupal\Core\Session\AccountInterface
+   *   Returns the current account object.
+   */
+  protected function prepareUser(AccountInterface $account = NULL) {
+    if (!$account) {
+      $account = \Drupal::currentUser();
+    }
+    return $account;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function fieldAccess($operation, FieldDefinitionInterface $field_definition, AccountInterface $account = NULL, FieldItemListInterface $items = NULL, $return_as_object = FALSE) {
+    $account = $this->prepareUser($account);
+
+    // Get the default access restriction that lives within this field.
+    $default = $items ? $items->defaultAccess($operation, $account) : AccessResult::allowed();
+
+    // Explicitly disallow changing the entity ID and entity UUID.
+    if ($operation === 'edit') {
+      if ($field_definition->getName() === $this->entityType->getKey('id')) {
+        return $return_as_object ? AccessResult::forbidden('The entity ID cannot be changed') : FALSE;
+      }
+      elseif ($field_definition->getName() === $this->entityType->getKey('uuid')) {
+        // UUIDs can be set when creating an entity.
+        if ($items && ($entity = $items->getEntity()) && !$entity->isNew()) {
+          return $return_as_object ? AccessResult::forbidden('The entity UUID cannot be changed')->addCacheableDependency($entity) : FALSE;
+        }
+      }
+    }
+
+    // Get the default access restriction as specified by the access control
+    // handler.
+    $entity_default = $this->checkFieldAccess($operation, $field_definition, $account, $items);
+
+    // Combine default access, denying access wins.
+    $default = $default->andIf($entity_default);
+
+    // Invoke hook and collect grants/denies for field access from other
+    // modules. Our default access flag is masked under the ':default' key.
+    $grants = [':default' => $default];
+    $hook_implementations = $this->moduleHandler()->getImplementations('entity_field_access');
+    foreach ($hook_implementations as $module) {
+      $grants = array_merge($grants, [$module => $this->moduleHandler()->invoke($module, 'entity_field_access', [$operation, $field_definition, $account, $items])]);
+    }
+
+    // Also allow modules to alter the returned grants/denies.
+    $context = [
+      'operation' => $operation,
+      'field_definition' => $field_definition,
+      'items' => $items,
+      'account' => $account,
+    ];
+    $this->moduleHandler()->alter('entity_field_access', $grants, $context);
+
+    $result = $this->processAccessHookResults($grants);
+    return $return_as_object ? $result : $result->isAllowed();
+  }
+
+  /**
+   * Default field access as determined by this access control handler.
+   *
+   * @param string $operation
+   *   The operation access should be checked for.
+   *   Usually one of "view" or "edit".
+   * @param \Drupal\Core\Field\FieldDefinitionInterface $field_definition
+   *   The field definition.
+   * @param \Drupal\Core\Session\AccountInterface $account
+   *   The user session for which to check access.
+   * @param \Drupal\Core\Field\FieldItemListInterface $items
+   *   (optional) The field values for which to check access, or NULL if access
+   *   is checked for the field definition, without any specific value
+   *   available. Defaults to NULL.
+   *
+   * @return \Drupal\Core\Access\AccessResultInterface
+   *   The access result.
+   */
+  protected function checkFieldAccess($operation, FieldDefinitionInterface $field_definition, AccountInterface $account, FieldItemListInterface $items = NULL) {
+    return AccessResult::allowed();
+  }
+
+}