<?php

namespace Drupal\Core\Entity;

/**
 * Defines methods for an entity that supports synchronization.
 */
interface SynchronizableInterface extends EntityInterface {

  /**
   * Sets the status of the synchronization flag.
   *
   * @param bool $status
   *   The status of the synchronization flag.
   *
   * @return $this
   */
  public function setSyncing($status);

  /**
   * Returns whether this entity is being changed as part of a synchronization.
   *
   * If you are writing code that responds to a change in this entity (insert,
   * update, delete, presave, etc.), and your code would result in a change to
   * this entity itself, a configuration change (whether related to this entity,
   * another entity, or non-entity configuration), you need to check and see if
   * this entity change is part of a synchronization process, and skip executing
   * your code if that is the case.
   *
   * For example, \Drupal\node\Entity\NodeType::postSave() adds the default body
   * field to newly created node type configuration entities, which is a
   * configuration change. You would not want this code to run during an import,
   * because imported entities were already given the body field when they were
   * originally created, and the imported configuration includes all of their
   * currently-configured fields. On the other hand,
   * \Drupal\field\Entity\FieldStorageConfig::preSave() and the methods it calls
   * make sure that the storage tables are created or updated for the field
   * storage configuration entity, which is not a configuration change, and it
   * must be done whether due to an import or not. So, the first method should
   * check $entity->isSyncing() and skip executing if it returns TRUE, and the
   * second should not perform this check.
   *
   * @return bool
   *   TRUE if the configuration entity is being created, updated, or deleted
   *   through a synchronization process.
   */
  public function isSyncing();

}