message_notification-1.0.1-beta1/message_notification.install

<?php

/**
 * @file
 * Install, update and uninstall functions for the my_message module.
 */

use Drupal\Core\Field\BaseFieldDefinition;
use Drupal\Core\Field\FieldStorageDefinitionInterface;

/**
 * Add the recipients field to message entity.
 */
function message_notification_update_9001() {
  // Skip if field already exists.
  $base_field_definitions =  \Drupal::service('entity_field.manager')->getBaseFieldDefinitions('message');
  if (!isset($base_field_definitions['recipients'])) {
    return;
  }

  $entity_definition_update = \Drupal::entityDefinitionUpdateManager();

  $storage_definition = BaseFieldDefinition::create('entity_reference')
    ->setLabel(t('Message recipients'))
    ->setDescription(t('List of users that received message.'))
    ->setSetting('target_type', 'user')
    ->setSetting('handler', 'default')
    ->setCardinality(FieldStorageDefinitionInterface::CARDINALITY_UNLIMITED);

  $entity_definition_update->installFieldStorageDefinition('recipients', 'message', 'message_notification', $storage_definition);

}