islandora/islandora.module

<?php

/**
 * @file
 * Contains islandora.module.
 *
 * This file is part of the Islandora Project.
 *
 * (c) Islandora Foundation
 *
 * For the full copyright and license information, please view the LICENSE
 * file that was distributed with this source code.
 *
 * @author Diego Pino Navarro <dpino@metro.org> https://github.com/diegopino
 */

use Drupal\Core\Database\IntegrityConstraintViolationException;
use Drupal\Core\Entity\EntityInterface;
use Drupal\Core\Routing\RouteMatchInterface;

/**
 * Implements hook_help().
 */
function islandora_help($route_name, RouteMatchInterface $route_match) {
  switch ($route_name) {
    // Main module help for the islandora module.
    case 'help.page.islandora':
      $output = '';
      $output .= '<h3>' . t('About') . '</h3>';
      $output .= '<p>' . t('Islandora integrates Drupal with a Fedora repository.') . '</p>';
      return $output;

    default:
  }
}

/**
 * Implements hook_modules_installed().
 */
function islandora_modules_installed($modules) {
  // Ensure the auth and serialization formats we need are available.
  if (in_array('rest', $modules)) {
    $rest_resource_config_storage = \Drupal::service('entity_type.manager')->getStorage('rest_resource_config');
    $rest_resource_config = $rest_resource_config_storage->load('entity.node');

    if ($rest_resource_config) {
      $configuration = $rest_resource_config->get('configuration');

      if (!in_array('jsonld', $configuration['formats'])) {
        $configuration['formats'][] = 'jsonld';
      }

      if (!in_array('jwt_auth', $configuration['authentication'])) {
        $configuration['authentication'][] = 'jwt_auth';
      }

      $rest_resource_config->set('configuration', $configuration);
      $rest_resource_config->save(TRUE);
    }
  }
}

/**
 * Implements hook_rdf_namespaces().
 */
function islandora_rdf_namespaces() {
  // Yes, it's amazing, rdf is not registered by default!
  return [
    'ldp'  => 'http://www.w3.org/ns/ldp#',
    'dc11' => 'http://purl.org/dc/elements/1.1/',
    'nfo' => 'http://www.semanticdesktop.org/ontologies/2007/03/22/nfo/v1.1/',
    'ebucore' => 'http://www.ebu.ch/metadata/ontologies/ebucore/ebucore#',
    'fedora' => 'http://fedora.info/definitions/v4/repository#',
    'owl' => 'http://www.w3.org/2002/07/owl#',
    'ore' => 'http://www.openarchives.org/ore/terms/',
    'rdf' => 'http://www.w3.org/1999/02/22-rdf-syntax-ns#',
    'islandora' => 'http://islandora.ca/CLAW/',
    'pcdm' => 'http://pcdm.org/models#',
    'use' => 'http://pcdm.org/use#',
    'iana' => 'http://www.iana.org/assignments/relation/',
  ];
}

/**
 * Implements hook_ENTITY_TYPE_insert().
 */
function islandora_node_insert(EntityInterface $entity) {
  // Creates a record in the db to track the number of changes to the entity.
  $versionCounter = \Drupal::service('islandora.versioncounter');
  try {
    $versionCounter->create($entity->uuid());
  }
  catch (IntegrityConstraintViolationException $e) {
    \Drupal::logger('islandora')->error(
      'Attempted to create duplicate entry for @uuid in version counter ' .
      'table. This should never happen.',
      ['@uuid' => $entity->uuid()]
    );
  }
}

/**
 * Implements hook_ENTITY_TYPE_update().
 */
function islandora_node_update(EntityInterface $entity) {
  // Increments the number of changes to the entity.
  $versionCounter = \Drupal::service('islandora.versioncounter');
  $versionCounter->increment($entity->uuid());
}

/**
 * Implements hook_ENTITY_TYPE_update().
 */
function islandora_node_delete(EntityInterface $entity) {
  // Deletes the record in the db to track the number of changes to the entity.
  $versionCounter = \Drupal::service('islandora.versioncounter');
  $versionCounter->delete($entity->uuid());
}

/**
 * Implements hook_node_view_alter().
 */
function islandora_node_view_alter(&$build, EntityInterface $entity) {
  // Return if memberof field does not exist.
  if ($entity->hasField('field_memberof') == FALSE) {
    return;
  }

  // Return if memberof field has no values.
  $collection_members = $entity->get('field_memberof')->getValue();
  if (count($collection_members) == 0) {
    return;
  }

  // Loop through each member and add to the collection_links.
  $collection_links = [];
  foreach ($collection_members as $member_info) {
    $collection_id = $member_info['target_id'];
    $collection_entity = $entity->load($collection_id);

    // If collection entity does not exist, skip.
    if ($collection_entity == NULL) {
      continue;
    }

    // If entity bundle type is not Collection, skip.
    $collection_entity_bundle = $collection_entity->bundle();
    if ($collection_entity_bundle != "islandora_collection") {
      continue;
    }

    $collection_entity_url = $collection_entity->url('canonical', ['absolute' => TRUE]);
    array_push($collection_links, "<" . $collection_entity_url . ">; rel='collection'");
  }

  if (count($collection_links) > 0) {
    $collection_links_str = implode(", ", $collection_links);
    $build['#attached']['http_header'] = [
      ['Link', $collection_links_str],
    ];
  }
}