drupal/core/modules/entity/entity.controller.inc

596 lines
18 KiB
PHP

<?php
/**
* @file
* Entity API controller classes and interface.
*/
/**
* Defines a common interface for entity controller classes.
*
* All entity controller classes specified via the 'controller class' key
* returned by hook_entity_info() or hook_entity_info_alter() have to implement
* this interface.
*
* Most simple, SQL-based entity controllers will do better by extending
* DrupalDefaultEntityController instead of implementing this interface
* directly.
*/
interface DrupalEntityControllerInterface {
/**
* Constructs a new DrupalEntityControllerInterface object.
*
* @param $entityType
* The entity type for which the instance is created.
*/
public function __construct($entityType);
/**
* Resets the internal, static entity cache.
*
* @param $ids
* (optional) If specified, the cache is reset for the entities with the
* given ids only.
*/
public function resetCache(array $ids = NULL);
/**
* Loads one or more entities.
*
* @param $ids
* An array of entity IDs, or FALSE to load all entities.
* @param $conditions
* An array of conditions in the form 'field' => $value.
*
* @return
* An array of entity objects indexed by their ids.
*/
public function load($ids = array(), $conditions = array());
}
/**
* Defines a base entity controller class.
*
* Default implementation of DrupalEntityControllerInterface.
*
* This class can be used as-is by most simple entity types. Entity types
* requiring special handling can extend the class.
*/
class DrupalDefaultEntityController implements DrupalEntityControllerInterface {
/**
* Static cache of entities.
*
* @var array
*/
protected $entityCache;
/**
* Entity type for this controller instance.
*
* @var string
*/
protected $entityType;
/**
* Array of information about the entity.
*
* @var array
*
* @see entity_get_info()
*/
protected $entityInfo;
/**
* Additional arguments to pass to hook_TYPE_load().
*
* Set before calling DrupalDefaultEntityController::attachLoad().
*
* @var array
*/
protected $hookLoadArguments;
/**
* Name of the entity's ID field in the entity database table.
*
* @var string
*/
protected $idKey;
/**
* Name of entity's revision database table field, if it supports revisions.
*
* Has the value FALSE if this entity does not use revisions.
*
* @var string
*/
protected $revisionKey;
/**
* The table that stores revisions, if the entity supports revisions.
*
* @var string
*/
protected $revisionTable;
/**
* Whether this entity type should use the static cache.
*
* Set by entity info.
*
* @var boolean
*/
protected $cache;
/**
* Implements DrupalEntityControllerInterface::__construct().
*
* Sets basic variables.
*/
public function __construct($entityType) {
$this->entityType = $entityType;
$this->entityInfo = entity_get_info($entityType);
$this->entityCache = array();
$this->hookLoadArguments = array();
$this->idKey = $this->entityInfo['entity keys']['id'];
// Check if the entity type supports revisions.
if (!empty($this->entityInfo['entity keys']['revision'])) {
$this->revisionKey = $this->entityInfo['entity keys']['revision'];
$this->revisionTable = $this->entityInfo['revision table'];
}
else {
$this->revisionKey = FALSE;
}
// Check if the entity type supports static caching of loaded entities.
$this->cache = !empty($this->entityInfo['static cache']);
}
/**
* Implements DrupalEntityControllerInterface::resetCache().
*/
public function resetCache(array $ids = NULL) {
if (isset($ids)) {
foreach ($ids as $id) {
unset($this->entityCache[$id]);
}
}
else {
$this->entityCache = array();
}
}
/**
* Implements DrupalEntityControllerInterface::load().
*/
public function load($ids = array(), $conditions = array()) {
$entities = array();
// Revisions are not statically cached, and require a different query to
// other conditions, so separate the revision id into its own variable.
if ($this->revisionKey && isset($conditions[$this->revisionKey])) {
$revision_id = $conditions[$this->revisionKey];
unset($conditions[$this->revisionKey]);
}
else {
$revision_id = FALSE;
}
// Create a new variable which is either a prepared version of the $ids
// array for later comparison with the entity cache, or FALSE if no $ids
// were passed. The $ids array is reduced as items are loaded from cache,
// and we need to know if it's empty for this reason to avoid querying the
// database when all requested entities are loaded from cache.
$passed_ids = !empty($ids) ? array_flip($ids) : FALSE;
// Try to load entities from the static cache, if the entity type supports
// static caching.
if ($this->cache && !$revision_id) {
$entities += $this->cacheGet($ids, $conditions);
// If any entities were loaded, remove them from the ids still to load.
if ($passed_ids) {
$ids = array_keys(array_diff_key($passed_ids, $entities));
}
}
// Load any remaining entities from the database. This is the case if $ids
// is set to FALSE (so we load all entities), if there are any ids left to
// load, if loading a revision, or if $conditions was passed without $ids.
if ($ids === FALSE || $ids || $revision_id || ($conditions && !$passed_ids)) {
// Build and execute the query.
$query_result = $this->buildQuery($ids, $conditions, $revision_id)->execute();
if (!empty($this->entityInfo['entity class'])) {
// We provide the necessary arguments for PDO to create objects of the
// specified entity class.
// @see EntityInterface::__construct()
$query_result->setFetchMode(PDO::FETCH_CLASS, $this->entityInfo['entity class'], array(array(), $this->entityType));
}
$queried_entities = $query_result->fetchAllAssoc($this->idKey);
}
// Pass all entities loaded from the database through $this->attachLoad(),
// which attaches fields (if supported by the entity type) and calls the
// entity type specific load callback, for example hook_node_load().
if (!empty($queried_entities)) {
$this->attachLoad($queried_entities, $revision_id);
$entities += $queried_entities;
}
if ($this->cache) {
// Add entities to the cache if we are not loading a revision.
if (!empty($queried_entities) && !$revision_id) {
$this->cacheSet($queried_entities);
}
}
// Ensure that the returned array is ordered the same as the original
// $ids array if this was passed in and remove any invalid ids.
if ($passed_ids) {
// Remove any invalid ids from the array.
$passed_ids = array_intersect_key($passed_ids, $entities);
foreach ($entities as $entity) {
$passed_ids[$entity->{$this->idKey}] = $entity;
}
$entities = $passed_ids;
}
return $entities;
}
/**
* Builds the query to load the entity.
*
* This has full revision support. For entities requiring special queries,
* the class can be extended, and the default query can be constructed by
* calling parent::buildQuery(). This is usually necessary when the object
* being loaded needs to be augmented with additional data from another
* table, such as loading node type into comments or vocabulary machine name
* into terms, however it can also support $conditions on different tables.
* See CommentController::buildQuery() or TaxonomyTermController::buildQuery()
* for examples.
*
* @param $ids
* An array of entity IDs, or FALSE to load all entities.
* @param $conditions
* An array of conditions in the form 'field' => $value.
* @param $revision_id
* The ID of the revision to load, or FALSE if this query is asking for the
* most current revision(s).
*
* @return SelectQuery
* A SelectQuery object for loading the entity.
*/
protected function buildQuery($ids, $conditions = array(), $revision_id = FALSE) {
$query = db_select($this->entityInfo['base table'], 'base');
$query->addTag($this->entityType . '_load_multiple');
if ($revision_id) {
$query->join($this->revisionTable, 'revision', "revision.{$this->idKey} = base.{$this->idKey} AND revision.{$this->revisionKey} = :revisionId", array(':revisionId' => $revision_id));
}
elseif ($this->revisionKey) {
$query->join($this->revisionTable, 'revision', "revision.{$this->revisionKey} = base.{$this->revisionKey}");
}
// Add fields from the {entity} table.
$entity_fields = $this->entityInfo['schema_fields_sql']['base table'];
if ($this->revisionKey) {
// Add all fields from the {entity_revision} table.
$entity_revision_fields = drupal_map_assoc($this->entityInfo['schema_fields_sql']['revision table']);
// The id field is provided by entity, so remove it.
unset($entity_revision_fields[$this->idKey]);
// Remove all fields from the base table that are also fields by the same
// name in the revision table.
$entity_field_keys = array_flip($entity_fields);
foreach ($entity_revision_fields as $key => $name) {
if (isset($entity_field_keys[$name])) {
unset($entity_fields[$entity_field_keys[$name]]);
}
}
$query->fields('revision', $entity_revision_fields);
}
$query->fields('base', $entity_fields);
if ($ids) {
$query->condition("base.{$this->idKey}", $ids, 'IN');
}
if ($conditions) {
foreach ($conditions as $field => $value) {
$query->condition('base.' . $field, $value);
}
}
return $query;
}
/**
* Attaches data to entities upon loading.
*
* This will attach fields, if the entity is fieldable. It calls
* hook_entity_load() for modules which need to add data to all entities.
* It also calls hook_TYPE_load() on the loaded entities. For example
* hook_node_load() or hook_user_load(). If your hook_TYPE_load()
* expects special parameters apart from the queried entities, you can set
* $this->hookLoadArguments prior to calling the method.
* See NodeController::attachLoad() for an example.
*
* @param $queried_entities
* Associative array of query results, keyed on the entity ID.
* @param $revision_id
* ID of the revision that was loaded, or FALSE if the most current revision
* was loaded.
*/
protected function attachLoad(&$queried_entities, $revision_id = FALSE) {
// Attach fields.
if ($this->entityInfo['fieldable']) {
if ($revision_id) {
field_attach_load_revision($this->entityType, $queried_entities);
}
else {
field_attach_load($this->entityType, $queried_entities);
}
}
// Call hook_entity_load().
foreach (module_implements('entity_load') as $module) {
$function = $module . '_entity_load';
$function($queried_entities, $this->entityType);
}
// Call hook_TYPE_load(). The first argument for hook_TYPE_load() are
// always the queried entities, followed by additional arguments set in
// $this->hookLoadArguments.
$args = array_merge(array($queried_entities), $this->hookLoadArguments);
foreach (module_implements($this->entityInfo['load hook']) as $module) {
call_user_func_array($module . '_' . $this->entityInfo['load hook'], $args);
}
}
/**
* Gets entities from the static cache.
*
* @param $ids
* If not empty, return entities that match these IDs.
* @param $conditions
* If set, return entities that match all of these conditions.
*
* @return
* Array of entities from the entity cache.
*/
protected function cacheGet($ids, $conditions = array()) {
$entities = array();
// Load any available entities from the internal cache.
if (!empty($this->entityCache)) {
if ($ids) {
$entities += array_intersect_key($this->entityCache, array_flip($ids));
}
// If loading entities only by conditions, fetch all available entities
// from the cache. Entities which don't match are removed later.
elseif ($conditions) {
$entities = $this->entityCache;
}
}
// Exclude any entities loaded from cache if they don't match $conditions.
// This ensures the same behavior whether loading from memory or database.
if ($conditions) {
foreach ($entities as $entity) {
$entity_values = (array) $entity;
if (array_diff_assoc($conditions, $entity_values)) {
unset($entities[$entity->{$this->idKey}]);
}
}
}
return $entities;
}
/**
* Stores entities in the static entity cache.
*
* @param $entities
* Entities to store in the cache.
*/
protected function cacheSet($entities) {
$this->entityCache += $entities;
}
}
/**
* Defines a common interface for entity storage controllers.
*/
interface EntityStorageControllerInterface extends DrupalEntityControllerInterface {
/**
* Constructs a new entity object, without permanently saving it.
*
* @param $values
* An array of values to set, keyed by property name. If the entity type has
* bundles the bundle key has to be specified.
*
* @return EntityInterface
* A new entity object.
*/
public function create(array $values);
/**
* Deletes permanently saved entities.
*
* @param $ids
* An array of entity IDs.
*
* @throws EntityStorageException
* In case of failures, an exception is thrown.
*/
public function delete($ids);
/**
* Saves the entity permanently.
*
* @param EntityInterface $entity
* The entity to save.
*
* @return
* SAVED_NEW or SAVED_UPDATED is returned depending on the operation
* performed.
*
* @throws EntityStorageException
* In case of failures, an exception is thrown.
*/
public function save(EntityInterface $entity);
}
/**
* Defines an exception thrown when storage operations fail.
*/
class EntityStorageException extends Exception { }
/**
* Implements the entity storage controller interface for the database.
*/
class EntityDatabaseStorageController extends DrupalDefaultEntityController implements EntityStorageControllerInterface {
/**
* Implements EntityStorageControllerInterface::create().
*/
public function create(array $values) {
$class = isset($this->entityInfo['entity class']) ? $this->entityInfo['entity class'] : 'Entity';
return new $class($values, $this->entityType);
}
/**
* Implements EntityStorageControllerInterface::delete().
*/
public function delete($ids) {
$entities = $ids ? $this->load($ids) : FALSE;
if (!$entities) {
// If no IDs or invalid IDs were passed, do nothing.
return;
}
$transaction = db_transaction();
try {
$this->preDelete($entities);
foreach ($entities as $id => $entity) {
$this->invokeHook('predelete', $entity);
}
$ids = array_keys($entities);
db_delete($this->entityInfo['base table'])
->condition($this->idKey, $ids, 'IN')
->execute();
// Reset the cache as soon as the changes have been applied.
$this->resetCache($ids);
$this->postDelete($entities);
foreach ($entities as $id => $entity) {
$this->invokeHook('delete', $entity);
}
// Ignore slave server temporarily.
db_ignore_slave();
}
catch (Exception $e) {
$transaction->rollback();
watchdog_exception($this->entityType, $e);
throw new EntityStorageException($e->getMessage, $e->getCode, $e);
}
}
/**
* Implements EntityStorageControllerInterface::save().
*/
public function save(EntityInterface $entity) {
$transaction = db_transaction();
try {
// Load the stored entity, if any.
if (!$entity->isNew() && !isset($entity->original)) {
$entity->original = entity_load_unchanged($this->entityType, $entity->id());
}
$this->preSave($entity);
$this->invokeHook('presave', $entity);
if (!$entity->isNew()) {
$return = drupal_write_record($this->entityInfo['base table'], $entity, $this->idKey);
$this->resetCache(array($entity->{$this->idKey}));
$this->postSave($entity, TRUE);
$this->invokeHook('update', $entity);
}
else {
$return = drupal_write_record($this->entityInfo['base table'], $entity);
// Reset general caches, but keep caches specific to certain entities.
$this->resetCache(array());
$entity->enforceIsNew(FALSE);
$this->postSave($entity, FALSE);
$this->invokeHook('insert', $entity);
}
// Ignore slave server temporarily.
db_ignore_slave();
unset($entity->original);
return $return;
}
catch (Exception $e) {
$transaction->rollback();
watchdog_exception($this->entityType, $e);
throw new EntityStorageException($e->getMessage(), $e->getCode(), $e);
}
}
/**
* Acts on an entity before the presave hook is invoked.
*
* Used before the entity is saved and before invoking the presave hook.
*/
protected function preSave(EntityInterface $entity) { }
/**
* Acts on a saved entity before the insert or update hook is invoked.
*
* Used after the entity is saved, but before invoking the insert or update
* hook.
*
* @param $update
* (bool) TRUE if the entity has been updated, or FALSE if it has been
* inserted.
*/
protected function postSave(EntityInterface $entity, $update) { }
/**
* Acts on entities before they are deleted.
*
* Used before the entities are deleted and before invoking the delete hook.
*/
protected function preDelete($entities) { }
/**
* Acts on deleted entities before the delete hook is invoked.
*
* Used after the entities are deleted but before invoking the delete hook.
*/
protected function postDelete($entities) { }
/**
* Invokes a hook on behalf of the entity.
*
* @param $hook
* One of 'presave', 'insert', 'update', 'predelete', or 'delete'.
* @param $entity
* The entity object.
*/
protected function invokeHook($hook, EntityInterface $entity) {
if (!empty($this->entityInfo['fieldable']) && function_exists($function = 'field_attach_' . $hook)) {
$function($this->entityType, $entity);
}
// Invoke the hook.
module_invoke_all($this->entityType . '_' . $hook, $entity);
// Invoke the respective entity-level hook.
module_invoke_all('entity_' . $hook, $entity, $this->entityType);
}
}