123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154155156157158159160161162163164165166167168169170171172173174175176177178179180181182183184185186187188189190191192193194195196197198199200201202203204205206207208209210211212213214215216217218219220221222223224225226227228229230231232233234235236237238239240241242243244245246247248249250251252253254255256257258259260261262263264265266267268269270271272273274275276277278279280281282283284285286287288289290291292293294295296297298299300301302303304305306307308309310311312313314315316317318319320321322323324325326327328329330331332333334335336337338339340341342343344345346347348349350351352353354355356357358359360361362363364365366367368369370371372373374375376377378379380381382383384385386387388389390391392393394395396397398399400401402403404405406407408409410411412413414415416417418419420421422423424425426427428429430431432433434435436437438439440441442443444445446447448449450451452453454455456457 |
- <?php
- /**
- * @file
- * Contains base code for CER handlers, which are objects responsible for
- * creating, updating and deleting corresponding references between entities.
- */
- /**
- * Exception related to CER operations.
- */
- class CerException extends Exception {
- }
- interface CerHandlerInterface {
- /**
- * @constructor
- *
- * @param string $preset
- * The CER preset string, in the format:
- * entity_a*bundle_a*field_a*entity_b*bundle_b*field_b.
- *
- * @param $entity.
- * The local (home) entity to be wrapped by this instance.
- */
- public function __construct($preset, $entity);
- /**
- * Create reciprocal references on referenced entities after the
- * local entity has been created.
- */
- public function insert();
- /**
- * Delete reciprocal references on entities the local entity is no
- * longer referencing, and create new reciprocal references, after
- * the local entity has been updated.
- */
- public function update();
- /**
- * Delete all reciprocal references after the local entity is deleted.
- */
- public function delete();
-
- /**
- * Check if $entity is referenced by the local entity.
- *
- * @param object $entity
- * The remote entity.
- *
- * @return boolean
- */
- public function references($entity);
- /**
- * Check if the local entity is referenced by $entity.
- *
- * @param object $entity
- * The remote entiy.
- *
- * @return boolean
- */
- public function referencedBy($entity);
-
- /**
- * Check if the remote entity can reference the local entity, and vice-versa.
- *
- * @param object $entity
- * The remote entity.
- *
- * @return boolean
- */
- public function referenceable($entity);
- /**
- * Create a reference to the local entity on the remote entity, and vice-versa
- * if needed. Should throw CerException if the reference(s) can't be created
- * for any reason.
- *
- * @param object $entity
- */
- public function reference($entity);
- /**
- * Delete all references to the remote entity from the local entity,
- * and delete reciprocal references from the remote entity.
- *
- * @param object $entity.
- */
- public function dereference($entity);
- }
- /**
- * @class
- * Base class for CER handlers. All this does is parse the preset
- * and store instance info about the local and remote fields.
- */
- abstract class CerHandlerBase {
- /**
- * Local field instance definition.
- */
- protected $local;
- /**
- * Remote field instance definition.
- */
- protected $remote;
- public function __construct($preset) {
- $keys = explode('*', $preset);
- if (sizeof($keys) != 6) {
- throw new CerException(t('Invalid configuration: @preset', array('@preset' => $preset)));
- }
- $this->local = field_info_instance($keys[0], $keys[2], $keys[1]);
- if ($this->local) {
- $this->local['field'] = field_info_field($keys[2]);
- }
- else {
- throw new CerException(t('Local field instance does not exist.'));
- }
- $this->remote = field_info_instance($keys[3], $keys[5], $keys[4]);
- if ($this->remote) {
- $this->remote['field'] = field_info_field($keys[5]);
- }
- else {
- throw new CerException(t('Remote field instance does not exist.'));
- }
- }
- }
- /**
- * @class
- * Generic CER handler with rudimentary language handling.
- */
- class CerHandler extends CerHandlerBase implements CerHandlerInterface {
- /**
- * The local (home) entity.
- */
- protected $entity;
- /**
- * The local entity's ID.
- */
- protected $id;
- /**
- * Implements CerHandlerInterface::__construct().
- */
- public function __construct($preset, $entity) {
- parent::__construct($preset);
- // If $entity is of the wrong type, entity_extract_IDs()
- // will throw EntityMalformedException here.
- $extract_ids = entity_extract_IDs($this->local['entity_type'], $entity);
- $this->id = array_shift($extract_ids);
- $this->entity = $entity;
- }
- /**
- * Implements CerHandlerInterface::insert().
- */
- public function insert($ids = NULL) {
- if (empty($ids)) {
- $entities = $this->getReferencedEntities();
- }
- else {
- $entities = entity_load($this->remote['entity_type'], $ids);
- }
- foreach ($entities as $referenced_entity) {
- $this->reference($referenced_entity);
- _cer_update($this->remote['entity_type'], $referenced_entity);
- }
- }
- /**
- * Implements CerHandlerInterface::update().
- */
- public function update() {
- $original = isset($this->entity->original) ? $this->entity->original : $this->entity;
- $deleted = array_diff($this->getReferenceIDs($original, $this->local), $this->getLocalReferenceIDs());
- if ($deleted) {
- $entities = entity_load($this->remote['entity_type'], $deleted);
- foreach ($entities as $referenced_entity) {
- $this->dereference($referenced_entity);
- _cer_update($this->remote['entity_type'], $referenced_entity);
- }
- }
- $added = array_diff($this->getLocalReferenceIDs(), $this->getReferenceIDs($original, $this->local));
- if (!empty($added)) {
- $this->insert($added);
- }
- }
- /**
- * Implements CerHandlerInterface::delete().
- */
- public function delete() {
- foreach ($this->getReferencedEntities() as $referenced_entity) {
- $this->dereference($referenced_entity);
- _cer_update($this->remote['entity_type'], $referenced_entity);
- }
- }
- /**
- * Implements CerHandlerInterface::references().
- */
- public function references($entity) {
- return in_array($this->getRemoteEntityID($entity), $this->getLocalReferenceIDs());
- }
- /**
- * Implements CerHandlerInterface::referencedBy().
- */
- public function referencedBy($entity) {
- return in_array($this->id, $this->getRemoteReferenceIDs($entity));
- }
- /**
- * Implements CerHandlerInterface::referenceable().
- */
- public function referenceable($entity) {
- $id = $this->getRemoteEntityID($entity);
- $allowed = array(
- entityreference_get_selection_handler(
- $this->local['field'],
- $this->local,
- $this->local['entity_type'],
- $this->entity
- )
- ->validateReferencableEntities(array($id)),
- entityreference_get_selection_handler(
- $this->remote['field'],
- $this->remote,
- $this->remote['entity_type'],
- $entity
- )
- ->validateReferencableEntities(array($this->id)),
- );
- return in_array($id, $allowed[0]) && in_array($this->id, $allowed[1]);
- }
- /**
- * Implements CerHandlerInterface::reference().
- */
- public function reference($entity) {
- if ($this->referenceable($entity)) {
- try {
- $this->addReferenceTo($entity);
- }
- catch (CerException $e) {
- // Fail silently
- }
-
- try {
- $this->addReferenceFrom($entity);
- }
- catch (CerException $e) {
- // Fail silently
- }
- }
- else {
- $variables = array(
- '!local_field' => $this->local['field_name'],
- '!local_type' => $this->local['entity_type'],
- '!local_id' => $this->id,
- '!remote_field' => $this->remote['field_name'],
- '!remote_type' => $this->remote['entity_type'],
- '!remote_id' => $this->getRemoteEntityID($entity),
- );
- watchdog('cer', 'Failed to reference !remote_field on !remote_type !remote_id from !local_field on !local_type !local_id.', $variables, WATCHDOG_ERROR);
- }
- }
- /**
- * Implements CerHandlerInterface::dereference().
- */
- public function dereference($entity) {
- if ($this->references($entity)) {
- $id = $this->getRemoteEntityID($entity);
- foreach ($this->entity->{$this->local['field_name']} as $language => $references) {
- foreach ($references as $delta => $reference) {
- if ($reference['target_id'] == $id) {
- unset($this->entity->{$this->local['field_name']}[$language][$delta]);
- }
- }
- }
- }
- if ($this->referencedBy($entity)) {
- foreach ($entity->{$this->remote['field_name']} as $language => $references) {
- foreach ($references as $delta => $reference) {
- if ($reference['target_id'] == $this->id) {
- unset($entity->{$this->remote['field_name']}[$language][$delta]);
- }
- }
- }
- }
- }
- /**
- * Creates a reference to the local entity on the remote entity. Throws CerException
- * if the local entity is already referenced by the remote entity, or if the remote
- * field cannot hold any more values.
- *
- * @param object $entity
- * The remote entity.
- */
- protected function addReferenceFrom($entity) {
- if ($this->referencedBy($entity)) {
- throw new CerException(t('Cannot create duplicate reference from remote entity.'));
- }
- elseif ($this->filled($this->getRemoteReferenceIDs($entity), $this->remote['field'])) {
- throw new CerException(t('Remote field cannot support any more references.'));
- }
- else {
- $languages = field_available_languages($this->remote['entity_type'], $this->remote['field']);
- foreach ($languages as $language) {
- $entity->{$this->remote['field_name']}[$language][] = array('target_id' => $this->id);
- }
- }
- }
- /**
- * Creates a reference to the remote entity on the local entity. Throws CerException
- * if the local entity already references the remote entity, or if the field cannot
- * hold any more values.
- *
- * @param object $entity
- * The remote entity.
- */
- protected function addReferenceTo($entity) {
- $id = $this->getRemoteEntityID($entity);
- if ($this->references($entity)) {
- throw new CerException(t('Cannot create duplicate reference to remote entity.'));
- }
- elseif ($this->filled($this->getLocalReferenceIDs(), $this->local['field'])) {
- throw new CerException(t('Local field cannot support any more references.'));
- }
- else {
- $languages = field_available_languages($this->local['entity_type'], $this->local['field']);
- foreach ($languages as $language) {
- $this->entity->{$this->local['field_name']}[$language][] = array('target_id' => $id);
- }
- }
- }
- /**
- * Get the ID of the remote entity. If the entity is of the wrong type,
- * EntityMalformedException will be thrown.
- *
- * @param object $entity
- * The remote entity.
- *
- * @return mixed
- * The remote entity ID.
- */
- protected function getRemoteEntityID($entity) {
- $extract_ids = entity_extract_IDs($this->remote['entity_type'], $entity);
- return array_shift($extract_ids);
- }
- /**
- * Gets all the entities referenced by the local entity.
- *
- * @return array
- * Array of fully loaded referenced entities keyed by ID, or empty
- * array if nothing has been referenced.
- */
- protected function getReferencedEntities() {
- $IDs = $this->getLocalReferenceIDs();
- return $IDs ? entity_load($this->remote['entity_type'], $IDs) : array();
- }
- /**
- * Gets the IDs of the entities referenced by the local entity.
- *
- * @return array
- * Array of entity IDs, empty array if there are no references.
- */
- protected function getLocalReferenceIDs() {
- return $this->getReferenceIDs($this->entity, $this->local);
- }
- /**
- * Gets the IDs of the entities referenced by $entity.
- *
- * @param object $entity
- * The remote entity.
- *
- * @return array
- * Array of entity IDs, empty array if there are no references.
- */
- protected function getRemoteReferenceIDs($entity) {
- return $this->getReferenceIDs($entity, $this->remote);
- }
- /**
- * Check if a field can support any more values. Formerly known as
- * "reference overloading".
- *
- * @param array $references
- * The values in the field.
- *
- * @param $field
- * Field definition (i.e., from field_info_field).
- *
- * @return boolean
- */
- private function filled($references, $field) {
- return $field['cardinality'] != FIELD_CARDINALITY_UNLIMITED && sizeof($references) >= $field['cardinality'];
- }
- /**
- * Gets all the referenced entity IDs from a specific field on $entity.
- *
- * @param object $entity
- * The entity to scan for references.
- *
- * @param array $field
- * Field or instance definition.
- *
- * @return array
- * Array of unique IDs, empty if there are no references or the field
- * does not exist on $entity.
- */
- private function getReferenceIDs($entity, $field) {
- $IDs = array();
- if (isset($entity->{$field['field_name']})) {
- foreach ($entity->{$field['field_name']} as $references) {
- foreach ($references as $reference) {
- $IDs[] = $reference['target_id'];
- }
- }
- }
- return array_unique(array_filter($IDs));
- }
- }
|