Save field data for an existing entity.
When calling this function outside an entity save operation be sure to clear caches for the entity:
entity_get_controller($entity_type)
->resetCache(array(
$entity_id,
));
$entity_type: The type of $entity; e.g. 'node' or 'user'.
$entity: The entity with fields to save.
function field_attach_update($entity_type, $entity) {
_field_invoke('update', $entity_type, $entity);
list($id, $vid, $bundle) = entity_extract_ids($entity_type, $entity);
// Let any module update field data before the storage engine, accumulating
// saved fields along the way.
$skip_fields = array();
foreach (module_implements('field_storage_pre_update') as $module) {
$function = $module . '_field_storage_pre_update';
$function($entity_type, $entity, $skip_fields);
}
// Collect the storage backends used by the remaining fields in the entities.
$storages = array();
foreach (field_info_instances($entity_type, $bundle) as $instance) {
$field = field_info_field_by_id($instance['field_id']);
$field_id = $field['id'];
$field_name = $field['field_name'];
// Leave the field untouched if $entity comes with no $field_name property,
// but empty the field if it comes as a NULL value or an empty array.
// Function property_exists() is slower, so we catch the more frequent
// cases where it's an empty array with the faster isset().
if (isset($entity->{$field_name}) || property_exists($entity, $field_name)) {
// Collect the storage backend if the field has not been written yet.
if (!isset($skip_fields[$field_id])) {
$storages[$field['storage']['type']][$field_id] = $field_id;
}
}
}
// Field storage backends save any remaining unsaved fields.
foreach ($storages as $storage => $fields) {
$storage_info = field_info_storage_types($storage);
module_invoke($storage_info['module'], 'field_storage_write', $entity_type, $entity, FIELD_STORAGE_UPDATE, $fields);
}
// Let other modules act on updating the entity.
module_invoke_all('field_attach_update', $entity_type, $entity);
$entity_info = entity_get_info($entity_type);
if ($entity_info['field cache']) {
cache_clear_all("field:{$entity_type}:{$id}", 'cache_field');
}
}