entity_language_fallback.module in Entity Language Fallback 8

Add fallback languages to entities.

File

entity_language_fallback.module

<?php

/**
 * @file
 * Add fallback languages to entities.
 */
use Drupal\Core\Entity\ContentEntityInterface;
use Drupal\Core\Entity\EntityInterface;
use Drupal\Core\Form\FormStateInterface;
use Drupal\entity_language_fallback\Plugin\search_api\datasource\ContentEntityFallback;
use Drupal\language\ConfigurableLanguageInterface;

/**
 * Implements hook_language_fallback_candidates_alter()
 */
function entity_language_fallback_language_fallback_candidates_alter(array &$candidates, array $context) {
  $operation = $context['operation'];
  if ($operation == 'entity_upcast' || $operation == 'entity_view') {

    /* @var $fallback_controller \Drupal\entity_language_fallback\FallbackController */
    $fallback_controller = \Drupal::service('language_fallback.controller');
    if ($new_candidates = $fallback_controller
      ->getEntityFallbackCandidates($context['data'], $context['langcode'])) {
      $candidates = $new_candidates;
    }
  }
}

/**
 * Implements hook_form_FORM_ID_alter()
 */
function entity_language_fallback_form_language_admin_edit_form_alter(&$form, FormStateInterface $form_state) {

  /** @var Drupal\language\Entity\ConfigurableLanguage $this_language */
  $this_language = $form_state
    ->getFormObject()
    ->getEntity();
  $languages = Drupal::languageManager()
    ->getLanguages();
  $options = [];
  foreach ($languages as $language) {

    // Only include this language if its not itself.
    if ($language
      ->getId() != $this_language
      ->getId()) {
      $options[$language
        ->getId()] = $language
        ->getName();
    }
  }
  $form['entity_language_fallback'] = [
    '#title' => t('Entity fallback language'),
    '#description' => t('Choose one or more fallback languages in prioritized order. The languages are used as fallback in entity view.'),
    '#type' => 'details',
    '#open' => TRUE,
    '#tree' => TRUE,
  ];

  // Creating one priority field per available language.
  $default_values = $this_language
    ->getThirdPartySetting('entity_language_fallback', 'fallback_langcodes', []);
  for ($i = 0; $i < count($options); $i++) {
    $form['entity_language_fallback'][$i] = [
      '#type' => 'select',
      '#title' => t('Priority @priority', [
        '@priority' => $i + 1,
      ]),
      '#description' => t('Choose the language used as priority @priority fallback language.', [
        '@priority' => $i + 1,
      ]),
      '#options' => $options,
      '#default_value' => !empty($default_values[$i]) ? $default_values[$i] : '',
      '#empty_option' => t('-None-'),
      '#tree' => TRUE,
    ];
  }
  $form['#entity_builders'][] = 'entity_language_fallback_form_language_admin_edit_form_builder';
}

/**
 * Entity builder for the language form entity_language_fallback options.
 *
 * @see entity_language_fallback_form_language_admin_edit_form_alter()
 */
function entity_language_fallback_form_language_admin_edit_form_builder($entity_type, ConfigurableLanguageInterface $this_language, &$form, FormStateInterface $form_state) {
  $this_language
    ->setThirdPartySetting('entity_language_fallback', 'fallback_langcodes', $form_state
    ->getValue('entity_language_fallback'));
}

/**
 * Implements hook_entity_insert().
 *
 * Modified version of search_api_entity_insert().
 * @see search_api_entity_insert()
 */
function entity_language_fallback_entity_insert(EntityInterface $entity) {
  if (!\Drupal::moduleHandler()
    ->moduleExists('search_api')) {
    return;
  }

  // Check if the entity is a content entity.
  if (!$entity instanceof ContentEntityInterface || $entity->search_api_skip_tracking) {
    return;
  }
  $indexes = ContentEntityFallback::getIndexesForEntity($entity);
  if (!$indexes) {
    return;
  }

  // Compute the item IDs for all languages set up on the language fallback chain.
  $item_ids = [];
  $entity_id = $entity
    ->id();
  $fallback_controller = \Drupal::service('language_fallback.controller');
  $fallback_languages = array_keys($fallback_controller
    ->getTranslations($entity));
  foreach ($fallback_languages as $langcode) {
    $item_ids[] = $entity_id . ':' . $langcode;
  }
  $datasource_id = 'entity_language_fallback:' . $entity
    ->getEntityTypeId();
  foreach ($indexes as $index) {
    $filtered_item_ids = ContentEntityFallback::filterValidItemIds($index, $datasource_id, $item_ids);
    $index
      ->trackItemsInserted($datasource_id, $filtered_item_ids);
  }
}

/**
 * Implements hook_entity_update().
 *
 * search_api_entity_update() can only update items that are in ContentEntity
 * datasources.
 *
 * @see search_api_entity_update().
 */
function entity_language_fallback_entity_update(EntityInterface $entity) {
  if (!\Drupal::moduleHandler()
    ->moduleExists('search_api')) {
    return;
  }

  // Check if the entity is a content entity.
  if (!$entity instanceof ContentEntityInterface || $entity->search_api_skip_tracking) {
    return;
  }
  $indexes = ContentEntityFallback::getIndexesForEntity($entity);
  if (!$indexes) {
    return;
  }

  /** @var \Drupal\entity_language_fallback\FallbackControllerInterface $fallback_controller */
  static $fallback_controller;
  if (!isset($fallback_controller)) {
    $fallback_controller = \Drupal::service('language_fallback.controller');
  }

  // Compare old and new languages for the entity to identify inserted,
  // updated and deleted translations (and, therefore, search items).
  $entity_id = $entity
    ->id();
  $inserted_item_ids = [];
  $updated_item_ids = $fallback_controller
    ->getTranslations($entity);
  $deleted_item_ids = [];
  $old_translations = $fallback_controller
    ->getTranslations($entity->original);
  foreach ($old_translations as $langcode => $language) {
    if (!isset($updated_item_ids[$langcode])) {
      $deleted_item_ids[] = $langcode;
    }
  }
  foreach ($updated_item_ids as $langcode => $language) {
    if (!isset($old_translations[$langcode])) {
      unset($updated_item_ids[$langcode]);
      $inserted_item_ids[] = $langcode;
    }
  }
  $datasource_id = 'entity_language_fallback:' . $entity
    ->getEntityTypeId();
  $combine_id = function ($langcode) use ($entity_id) {
    return $entity_id . ':' . $langcode;
  };
  $inserted_item_ids = array_map($combine_id, $inserted_item_ids);
  $updated_item_ids = array_map($combine_id, array_keys($updated_item_ids));
  $deleted_item_ids = array_map($combine_id, $deleted_item_ids);
  foreach ($indexes as $index) {
    if ($inserted_item_ids) {
      $filtered_item_ids = ContentEntityFallback::filterValidItemIds($index, $datasource_id, $inserted_item_ids);
      $index
        ->trackItemsInserted($datasource_id, $filtered_item_ids);
    }
    if ($updated_item_ids) {
      $index
        ->trackItemsUpdated($datasource_id, $updated_item_ids);
    }
    if ($deleted_item_ids) {
      $index
        ->trackItemsDeleted($datasource_id, $deleted_item_ids);
    }
  }
}

/**
 * Implements hook_entity_delete().
 *
 * Deletes all entries for this entity from the tracking table for each index
 * that tracks this entity type.
 *
 * By setting the $entity->search_api_skip_tracking property to a true-like
 * value before this hook is invoked, you can prevent this behavior and make the
 * Search API ignore this deletion. (Note that this might lead to stale data in
 * the tracking table or on the server, since the item will not removed from
 * there (if it has been added before).)
 *
 * Note that this function implements tracking only on behalf of the "Content
 * Entity" datasource defined in this module, not for entity-based datasources
 * in general. Datasources defined by other modules still have to implement
 * their own mechanism for tracking new/updated/deleted entities.
 *
 * @see \Drupal\search_api\Plugin\search_api\datasource\ContentEntity
 */
function entity_language_fallback_entity_delete(EntityInterface $entity) {
  if (!\Drupal::moduleHandler()
    ->moduleExists('search_api')) {
    return;
  }

  // Check if the entity is a content entity.
  if (!$entity instanceof ContentEntityInterface || $entity->search_api_skip_tracking) {
    return;
  }
  $indexes = ContentEntityFallback::getIndexesForEntity($entity);
  if (!$indexes) {
    return;
  }

  // Remove the search items for all the entity's translations.
  $item_ids = [];
  $entity_id = $entity
    ->id();
  foreach (array_keys($entity
    ->getTranslationLanguages()) as $langcode) {
    $item_ids[] = $entity_id . ':' . $langcode;
  }
  $datasource_id = 'entity:' . $entity
    ->getEntityTypeId();
  foreach ($indexes as $index) {
    $index
      ->trackItemsDeleted($datasource_id, $item_ids);
  }
}

/**
 * Implements hook_search_api_index_items_alter().
 */
function entity_language_fallback_search_api_index_items_alter(\Drupal\search_api\IndexInterface $index, array &$items) {

  /** @var Drupal\search_api\Item\Item $item */
  foreach ($items as &$item) {
    $object = $item
      ->getOriginalObject(TRUE);
    $lang = isset($object->language) ? $object->language : $object
      ->getValue()->langcode->value;
    if ($lang) {
      $item
        ->setLanguage($lang);
    }
  }
}

Functions

Name	Description
entity_language_fallback_entity_delete	Implements hook_entity_delete().
entity_language_fallback_entity_insert	Implements hook_entity_insert().
entity_language_fallback_entity_update	Implements hook_entity_update().
entity_language_fallback_form_language_admin_edit_form_alter	Implements hook_form_FORM_ID_alter()
entity_language_fallback_form_language_admin_edit_form_builder	Entity builder for the language form entity_language_fallback options.
entity_language_fallback_language_fallback_candidates_alter	Implements hook_language_fallback_candidates_alter()
entity_language_fallback_search_api_index_items_alter	Implements hook_search_api_index_items_alter().