taxonomy.module

<?php


/**
 * @file
 * Enables the organization of content into categories.
 */
use Drupal\Core\Entity\EntityInterface;
use Drupal\Core\Entity\Sql\SqlContentEntityStorage;
use Drupal\Core\Render\Element;
use Drupal\Core\Routing\RouteMatchInterface;
use Drupal\Core\Url;
use Drupal\taxonomy\Entity\Term;
use Drupal\taxonomy\VocabularyInterface;

/**
 * Implements hook_help().
 */
function taxonomy_help($route_name, RouteMatchInterface $route_match) {
    switch ($route_name) {
        case 'help.page.taxonomy':
            $field_ui_url = \Drupal::moduleHandler()->moduleExists('field_ui') ? Url::fromRoute('help.page', [
                'name' => 'field_ui',
            ])->toString() : '#';
            $output = '';
            $output .= '<h2>' . t('About') . '</h2>';
            $output .= '<p>' . t('The Taxonomy module allows users who have permission to create and edit content to categorize (tag) content of that type. Users who have the <em>Administer vocabularies and terms</em> <a href=":permissions" title="Taxonomy module permissions">permission</a> can add <em>vocabularies</em> that contain a set of related <em>terms</em>. The terms in a vocabulary can either be pre-set by an administrator or built gradually as content is added and edited. Terms may be organized hierarchically if desired.', [
                ':permissions' => Url::fromRoute('user.admin_permissions.module', [
                    'modules' => 'taxonomy',
                ])->toString(),
            ]) . '</p>';
            $output .= '<p>' . t('For more information, see the <a href=":taxonomy">online documentation for the Taxonomy module</a>.', [
                ':taxonomy' => 'https://www.drupal.org/docs/8/core/modules/taxonomy',
            ]) . '</p>';
            $output .= '<h2>' . t('Uses') . '</h2>';
            $output .= '<dl>';
            $output .= '<dt>' . t('Managing vocabularies') . '</dt>';
            $output .= '<dd>' . t('Users who have the <em>Administer vocabularies and terms</em> permission can add and edit vocabularies from the <a href=":taxonomy_admin">Taxonomy administration page</a>. Vocabularies can be deleted from their <em>Edit vocabulary</em> page. Users with the <em>Taxonomy term: Administer fields</em> permission may add additional fields for terms in that vocabulary using the <a href=":field_ui">Field UI module</a>.', [
                ':taxonomy_admin' => Url::fromRoute('entity.taxonomy_vocabulary.collection')->toString(),
                ':field_ui' => $field_ui_url,
            ]) . '</dd>';
            $output .= '<dt>' . t('Managing terms') . '</dt>';
            $output .= '<dd>' . t('Users who have the <em>Administer vocabularies and terms</em> permission or the <em>Edit terms</em> permission for a particular vocabulary can add, edit, and organize the terms in a vocabulary from a vocabulary\'s term listing page, which can be accessed by going to the <a href=":taxonomy_admin">Taxonomy administration page</a> and clicking <em>List terms</em> in the <em>Operations</em> column. Users must have the <em>Administer vocabularies and terms</em> permission or the <em>Delete terms</em> permission for a particular vocabulary to delete terms.', [
                ':taxonomy_admin' => Url::fromRoute('entity.taxonomy_vocabulary.collection')->toString(),
            ]) . ' </dd>';
            $output .= '<dt>' . t('Classifying entity content') . '</dt>';
            $output .= '<dd>' . t('A user with the <em>Administer fields</em> permission for a certain entity type may add <em>Taxonomy term</em> reference fields to the entity type, which will allow entities to be classified using taxonomy terms. See the <a href=":entity_reference">Entity Reference help</a> for more information about reference fields. See the <a href=":field">Field module help</a> and the <a href=":field_ui">Field UI help</a> pages for general information on fields and how to create and manage them.', [
                ':field_ui' => $field_ui_url,
                ':field' => Url::fromRoute('help.page', [
                    'name' => 'field',
                ])->toString(),
                ':entity_reference' => Url::fromRoute('help.page', [
                    'name' => 'entity_reference',
                ])->toString(),
            ]) . '</dd>';
            $output .= '<dt>' . t('Adding new terms during content creation') . '</dt>';
            $output .= '<dd>' . t("Allowing users to add new terms gradually builds a vocabulary as content is added and edited. Users can add new terms if either of the two <em>Autocomplete</em> widgets is chosen for the Taxonomy term reference field in the <em>Manage form display</em> page for the field. You will also need to enable the <em>Create referenced entities if they don't already exist</em> option, and restrict the field to one vocabulary.") . '</dd>';
            $output .= '<dt>' . t('Configuring displays and form displays') . '</dt>';
            $output .= '<dd>' . t('See the <a href=":entity_reference">Entity Reference help</a> page for the field widgets and formatters that can be configured for any reference field on the <em>Manage display</em> and <em>Manage form display</em> pages. Taxonomy additionally provides an <em>RSS category</em> formatter that displays nothing when the entity item is displayed as HTML, but displays an RSS category instead of a list when the entity item is displayed in an RSS feed.', [
                ':entity_reference' => Url::fromRoute('help.page', [
                    'name' => 'entity_reference',
                ])->toString(),
            ]) . '</li>';
            $output .= '</ul>';
            $output .= '</dd>';
            $output .= '</dl>';
            return $output;
        case 'entity.taxonomy_vocabulary.collection':
            $output = '<p>' . t('Taxonomy is for categorizing content. Terms are grouped into vocabularies. For example, a vocabulary called "Fruit" would contain the terms "Apple" and "Banana".') . '</p>';
            return $output;
    }
}

/**
 * Implements hook_theme().
 */
function taxonomy_theme() {
    return [
        'taxonomy_term' => [
            'render element' => 'elements',
        ],
    ];
}

/**
 * Implements hook_theme_suggestions_HOOK().
 */
function taxonomy_theme_suggestions_taxonomy_term(array $variables) {
    $suggestions = [];
    
    /** @var \Drupal\taxonomy\TermInterface $term */
    $term = $variables['elements']['#taxonomy_term'];
    $suggestions[] = 'taxonomy_term__' . $term->bundle();
    $suggestions[] = 'taxonomy_term__' . $term->id();
    return $suggestions;
}

/**
 * Implements hook_local_tasks_alter().
 *
 * @todo Evaluate removing as part of https://www.drupal.org/node/2358923.
 */
function taxonomy_local_tasks_alter(&$local_tasks) {
    $local_task_key = 'config_translation.local_tasks:entity.taxonomy_vocabulary.config_translation_overview';
    if (isset($local_tasks[$local_task_key])) {
        // The config_translation module expects the base route to be
        // entity.taxonomy_vocabulary.edit_form like it is for other configuration
        // entities. Taxonomy uses the overview_form as the base route.
        $local_tasks[$local_task_key]['base_route'] = 'entity.taxonomy_vocabulary.overview_form';
    }
}

/**
 * Prepares variables for taxonomy term templates.
 *
 * Default template: taxonomy-term.html.twig.
 *
 * By default this function performs special preprocessing to move the name
 * base field out of the elements array into a separate variable. This
 * preprocessing is skipped if:
 * - a module makes the field's display configurable via the field UI by means
 *   of BaseFieldDefinition::setDisplayConfigurable()
 * - AND the additional entity type property
 *   'enable_base_field_custom_preprocess_skipping' has been set using
 *   hook_entity_type_build().
 *
 * @param array $variables
 *   An associative array containing:
 *   - elements: An associative array containing the taxonomy term and any
 *     fields attached to the term. Properties used:
 *     - #taxonomy_term: A \Drupal\taxonomy\TermInterface object.
 *     - #view_mode: The current view mode for this taxonomy term, e.g.
 *       'full' or 'teaser'.
 *   - attributes: HTML attributes for the containing element.
 */
function template_preprocess_taxonomy_term(&$variables) {
    $variables['view_mode'] = $variables['elements']['#view_mode'];
    $variables['term'] = $variables['elements']['#taxonomy_term'];
    
    /** @var \Drupal\taxonomy\TermInterface $term */
    $term = $variables['term'];
    $variables['url'] = !$term->isNew() ? $term->toUrl()
        ->toString() : NULL;
    // Make name field available separately.  Skip this custom preprocessing if
    // the field display is configurable and skipping has been enabled.
    // @todo https://www.drupal.org/project/drupal/issues/3015623
    //   Eventually delete this code and matching template lines. Using
    //   $variables['content'] is more flexible and consistent.
    $skip_custom_preprocessing = $term->getEntityType()
        ->get('enable_base_field_custom_preprocess_skipping');
    if (!$skip_custom_preprocessing || !$term->getFieldDefinition('name')
        ->isDisplayConfigurable('view')) {
        // We use name here because that is what appears in the UI.
        $variables['name'] = $variables['elements']['name'];
        unset($variables['elements']['name']);
    }
    $variables['page'] = $variables['view_mode'] == 'full' && taxonomy_term_is_page($term);
    // Helpful $content variable for templates.
    $variables['content'] = [];
    foreach (Element::children($variables['elements']) as $key) {
        $variables['content'][$key] = $variables['elements'][$key];
    }
}

/**
 * Implements hook_entity_operation().
 */
function taxonomy_entity_operation(EntityInterface $term) {
    $operations = [];
    if ($term instanceof Term && $term->access('create')) {
        $operations['add-child'] = [
            'title' => t('Add child'),
            'weight' => 10,
            'url' => Url::fromRoute('entity.taxonomy_term.add_form', [
                'taxonomy_vocabulary' => $term->bundle(),
            ], [
                'query' => [
                    'parent' => $term->id(),
                ],
            ]),
        ];
    }
    return $operations;
}

/**
 * Returns whether the current page is the page of the passed-in term.
 *
 * @param \Drupal\taxonomy\Entity\Term $term
 *   A taxonomy term entity.
 */
function taxonomy_term_is_page(Term $term) {
    if (\Drupal::routeMatch()->getRouteName() == 'entity.taxonomy_term.canonical' && ($page_term_id = \Drupal::routeMatch()->getRawParameter('taxonomy_term'))) {
        return $page_term_id == $term->id();
    }
    return FALSE;
}

/**
 * @defgroup taxonomy_index Taxonomy indexing
 * @{
 * Functions to maintain taxonomy indexing.
 *
 * Taxonomy uses default field storage to store canonical relationships
 * between terms and fieldable entities. However its most common use case
 * requires listing all content associated with a term or group of terms
 * sorted by creation date. To avoid slow queries due to joining across
 * multiple node and field tables with various conditions and order by criteria,
 * we maintain a denormalized table with all relationships between terms,
 * published nodes and common sort criteria such as status, sticky and created.
 * When using other field storage engines or alternative methods of
 * denormalizing this data you should set the
 * taxonomy.settings:maintain_index_table to '0' to avoid unnecessary writes in
 * SQL.
 */

/**
 * Implements hook_ENTITY_TYPE_insert() for node entities.
 */
function taxonomy_node_insert(EntityInterface $node) {
    // Add taxonomy index entries for the node.
    taxonomy_build_node_index($node);
}

/**
 * Builds and inserts taxonomy index entries for a given node.
 *
 * The index lists all terms that are related to a given node entity, and is
 * therefore maintained at the entity level.
 *
 * @param \Drupal\node\Entity\Node $node
 *   The node entity.
 */
function taxonomy_build_node_index($node) {
    // We maintain a denormalized table of term/node relationships, containing
    // only data for current, published nodes.
    if (!\Drupal::config('taxonomy.settings')->get('maintain_index_table') || !\Drupal::entityTypeManager()->getStorage('node') instanceof SqlContentEntityStorage) {
        return;
    }
    $status = $node->isPublished();
    $sticky = (int) $node->isSticky();
    // We only maintain the taxonomy index for published nodes.
    if ($status && $node->isDefaultRevision()) {
        // Collect a unique list of all the term IDs from all node fields.
        $tid_all = [];
        $entity_reference_class = 'Drupal\\Core\\Field\\Plugin\\Field\\FieldType\\EntityReferenceItem';
        foreach ($node->getFieldDefinitions() as $field) {
            $field_name = $field->getName();
            $class = $field->getItemDefinition()
                ->getClass();
            $is_entity_reference_class = $class === $entity_reference_class || is_subclass_of($class, $entity_reference_class);
            if ($is_entity_reference_class && $field->getSetting('target_type') == 'taxonomy_term') {
                foreach ($node->getTranslationLanguages() as $language) {
                    foreach ($node->getTranslation($language->getId())->{$field_name} as $item) {
                        if (!$item->isEmpty()) {
                            $tid_all[$item->target_id] = $item->target_id;
                        }
                    }
                }
            }
        }
        // Insert index entries for all the node's terms.
        if (!empty($tid_all)) {
            $connection = \Drupal::database();
            foreach ($tid_all as $tid) {
                $connection->merge('taxonomy_index')
                    ->keys([
                    'nid' => $node->id(),
                    'tid' => $tid,
                    'status' => $node->isPublished(),
                ])
                    ->fields([
                    'sticky' => $sticky,
                    'created' => $node->getCreatedTime(),
                ])
                    ->execute();
            }
        }
    }
}

/**
 * Implements hook_ENTITY_TYPE_update() for node entities.
 */
function taxonomy_node_update(EntityInterface $node) {
    // If we're not dealing with the default revision of the node, do not make any
    // change to the taxonomy index.
    if (!$node->isDefaultRevision()) {
        return;
    }
    taxonomy_delete_node_index($node);
    taxonomy_build_node_index($node);
}

/**
 * Implements hook_ENTITY_TYPE_predelete() for node entities.
 */
function taxonomy_node_predelete(EntityInterface $node) {
    // Clean up the {taxonomy_index} table when nodes are deleted.
    taxonomy_delete_node_index($node);
}

/**
 * Deletes taxonomy index entries for a given node.
 *
 * @param \Drupal\Core\Entity\EntityInterface $node
 *   The node entity.
 */
function taxonomy_delete_node_index(EntityInterface $node) {
    if (\Drupal::config('taxonomy.settings')->get('maintain_index_table')) {
        \Drupal::database()->delete('taxonomy_index')
            ->condition('nid', $node->id())
            ->execute();
    }
}

/**
 * Implements hook_ENTITY_TYPE_delete() for taxonomy_term entities.
 */
function taxonomy_taxonomy_term_delete(Term $term) {
    if (\Drupal::config('taxonomy.settings')->get('maintain_index_table')) {
        // Clean up the {taxonomy_index} table when terms are deleted.
        \Drupal::database()->delete('taxonomy_index')
            ->condition('tid', $term->id())
            ->execute();
    }
}

/**
 * @} End of "defgroup taxonomy_index".
 */

/**
 * Implements hook_ENTITY_TYPE_presave().
 */
function taxonomy_taxonomy_vocabulary_presave(VocabularyInterface $vocabulary) {
    // Vocabularies' `description` field must be stored as NULL at the config
    // level if it is empty.
    // @see taxonomy_post_update_set_vocabulary_description_to_null()
    if (trim($vocabulary->getDescription()) === '') {
        $vocabulary->set('description', NULL);
    }
}