printable.module in Printer and PDF versions for Drupal 8+ 8

Provides printer friendly content entities.

File

printable.module

<?php

/**
 * @file
 * Provides printer friendly content entities.
 */
use Drupal\Core\Entity\EntityInterface;
use Drupal\Core\Entity\Display\EntityViewDisplayInterface;
use Drupal\Core\Template\Attribute;
use Symfony\Cmf\Component\Routing\RouteObjectInterface;
use Drupal\Core\Routing\RouteMatchInterface;

// Register autoloading of vendor libraries.
$autoload = __DIR__ . '/vendor/autoload.php';
if (file_exists($autoload)) {
  require_once $autoload;
}

/**
 * Implements hook_help().
 */
function printable_help($route_name, RouteMatchInterface $route_match) {
  if ($route_name !== 'help.page.printable') {
    return;
  }
  return t('
    <h3>Introduction</h3>
    <p>This module allows you to generate the following printer-friendly versions of any node:<br>
      <ul>
        <li>Web page printer-friendly version (at www.example.com/node/nid/printable/print)</li>
        <li>PDF version (at www.example.com/node/nid/printable/pdf)</li>
      </ul>
      where nid is the node id of content to render.)
    </p>
    <h3>Installation</h3>
    <p>This will simplify a lot once <a href="https://www.drupal.org/project/drupal/issues/2494073">https://www.drupal.org/project/drupal/issues/2494073</a>
    is fixed:<br>
      <ul>
        <li>Download this module either using composer or by getting it directly from drupal.org: <br>
          <code>composer require drupal/printable</code>
        </li>
        <li>Install this module\'s composer dependencies - they can be found in composer.json in the project directory. Run composer require for each dependency from the Drupal root:<br>
          <code>
            composer require \'wa72/htmlpagedom\': \'1.3.*\'<br>
            composer require \'smalot/pdfparser\': \'*\'<br>
          </code>
        </li>
        <li>Enable printable:<br>
          <code>drush en -y printable</code>
        </li>
      </ul>
    </p>');
}

/**
 * Implements hook_permission().
 */
function printable_permission() {
  return [
    'view printer friendly versions' => [
      'title' => t('View Printer Friendly Versions'),
    ],
    'administer printable' => [
      'title' => t('Administer Printable'),
    ],
  ];
}

/**
 * Implements hook_theme().
 */
function printable_theme() {
  $module_path = drupal_get_path('module', 'printable');
  return [
    'printable_navigation' => [
      'variables' => [
        'printable_link' => NULL,
      ],
    ],
    'printable' => [
      'template' => 'printable',
      'pattern' => 'printable__',
      'variables' => [
        'header' => NULL,
        'content' => NULL,
        'footer' => NULL,
      ],
      'path' => $module_path . '/templates',
    ],
    'printable_header' => [
      'template' => 'printable-header',
      'pattern' => 'printable_header__',
      'variables' => [
        'logo_url' => NULL,
      ],
      'path' => $module_path . '/templates',
    ],
    'printable_footer' => [
      'template' => 'printable-footer',
      'pattern' => 'printable_footer__',
      'variables' => [
        'footer_content' => NULL,
      ],
      'path' => $module_path . '/templates',
    ],
  ];
}

/**
 * Preprocess variables for list of printable printer friendly page.
 *
 * @param array $variables
 *   An associative array containing:
 *   - elements: Array of participant names.
 *     Array keys: #base_url, #title, #html_attributes, #send_script,
 *     #include_css.
 */
function template_preprocess_printable(array &$variables) {
  global $base_url;
  $config = \Drupal::config('printable.settings');
  $variables['base_url'] = $base_url . '/' . drupal_get_path('module', 'printable');
  $request = \Drupal::request();
  $title = '';
  if ($route = $request->attributes
    ->get(RouteObjectInterface::ROUTE_OBJECT)) {
    $title = \Drupal::service('title_resolver')
      ->getTitle($request, $route);
  }
  $variables['title'] = $title;
  $language_interface = \Drupal::languageManager()
    ->getCurrentLanguage();
  $variables['html_attributes'] = new Attribute([
    'lang' => $language_interface
      ->getId(),
    'dir' => $language_interface
      ->getDirection(),
  ]);
  if ($config
    ->get('send_to_printer')) {
    $variables['send_script'] = $variables['base_url'] . '/js/script.js';
    if ($config
      ->get('close_window')) {
      $variables['close_script'] = $variables['base_url'] . '/js/close.js';
    }
  }
  if ($include_path = \Drupal::service('printable.css_include')
    ->getCssIncludePath()) {
    $variables['include_css'] = $include_path;
  }
}

/**
 * Preprocess variables for list of printable printer friendly page.
 *
 * @param array $variables
 *   An associative array containing
 *   - elements: Array of participant names.
 *     Array keys: #source_url, #footer_links, #footer_content.
 */
function template_preprocess_printable_footer(array &$variables) {
  global $base_url;

  // Create source url over here.
  $source_url = \Drupal::service('path.current')
    ->getPath();
  $pos = strpos($source_url, "printable");
  $source_url = substr($source_url, 0, $pos - 1);
  $source_url = $base_url . \Drupal::service('path.alias_manager')
    ->getAliasByPath($source_url);
  $variables['source_url'] = $source_url;
  if (\Drupal::service('config.factory')
    ->get('printable.settings')
    ->get('list_attribute')) {
    $links = $variables['footer_content'];
    $split_links = explode(',', $links);
    $new_array = array_unique($split_links);
    $variables['footer_links'] = $new_array;
  }
}

/**
 * Implements hook_entity_view_mode_alter().
 */
function printable_entity_view_mode_info_alter(&$view_modes) {
  $printable_manager = \Drupal::service('printable.entity_manager');
  foreach ($printable_manager
    ->getPrintableEntities() as $entity_type => $entity_definition) {

    // Add an additional view mode to this entity.
    $view_modes[$entity_type]['printable'] = [
      'id' => $entity_type . '.printable',
      'targetEntityType' => $entity_type,
      'label' => t('Printable'),
      'custom_settings' => FALSE,
      'cache' => TRUE,
    ];
  }
}

/**
 * Implements hook_entity_view().
 */
function printable_entity_view(array &$build, EntityInterface $entity, EntityViewDisplayInterface $display, $view_mode) {
  $config = \Drupal::config('printable.settings');
  \Drupal::service('renderer')
    ->addCacheableDependency($build, $config);
  $printable_manager = \Drupal::service('printable.entity_manager');
  $link_builder = \Drupal::service('printable.link_builder');
  if ($printable_manager
    ->isPrintableEntity($entity) && !empty($entity
    ->id())) {
    $print_setting = $config
      ->get('printable_print_link_locations');
    $pdf_setting = $config
      ->get('printable_pdf_link_locations');

    // Get the name of entity over here.
    $entity_name = $printable_manager
      ->getEntityName($entity);
    $printable_navigation = [
      '#theme' => 'links__entity__printable',
      '#links' => $link_builder
        ->buildLinks($entity),
      '#attributes' => [
        'class' => [
          'pre_links',
        ],
      ],
    ];
    if (!in_array($entity_name, $print_setting)) {
      unset($printable_navigation['#links']['print']);
    }
    $pdf_library = (string) $config
      ->get('pdf_tool');
    if (!$pdf_library || !in_array($entity_name, $pdf_setting)) {
      unset($printable_navigation['#links']['pdf']);
    }

    // Add the build links to the entity being rendered.
    $build['printable_navigation'] = [
      '#markup' => '<strong class="node_view">' . drupal_render($printable_navigation) . '</strong>',
      '#attached' => [
        'library' => [
          'printable/entity-links',
        ],
      ],
      '#weight' => 100,
      '#cache' => [
        'tags' => $entity
          ->getEntityType()
          ->getListCacheTags(),
      ],
    ];
  }
}

/**
 * Are we in the process of generating a printable version of content?
 *
 * @return bool
 *   Whether we are preparing a printable version of content.
 */
function printable_preparing_content() {
  $match = \Drupal::routeMatch();
  $route = $match
    ->getRouteObject();
  return $route && $route
    ->getPath() == '/node/{entity}/printable/{printable_format}';
}

/**
 * Are we in the process of generating a PDF?
 *
 * @return bool
 *   Whether we are preparing a PDF.
 */
function printable_preparing_pdf() {
  $match = \Drupal::routeMatch();
  $route = $match
    ->getRouteObject();
  return $route && $route
    ->getPath() == '/node/{entity}/printable/{printable_format}' && $match
    ->getParameter('printable_format') == 'pdf';
}

/**
 * Make file urls absolute if we're generating a PDF.
 *
 * @param string $uri
 *   URI to be altered.
 */
function printable_file_url_alter(&$uri) {
  if (printable_preparing_pdf()) {

    // Using the filesystem path makes images work across all libraries but
    // won't work with paths that require Drupal foo. I'd prefer to use URLs
    // but that doesn't work with all libraries :(.
    global $base_path;
    $scheme = \Drupal::service('file_system')
      ->uriScheme($uri);

    // If the file uses the public scheme,
    if ($scheme == 'public') {
      $path = \Drupal::service('file_system')
        ->realpath('public://');
      $uri = $path . '/' . substr($uri, 9);
    }
    else {
      $base_url = \Drupal::request()
        ->getSchemeAndHttpHost();
      if (substr($uri, 0, strlen($base_url)) == $base_url) {
        $uri = substr($uri, strlen($base_url) + 1);
      }
      $uri = DRUPAL_ROOT . '/' . $uri;
    }
  }
}

/**
 * Make Link URLs absolute if we're generating a PDF.
 *
 * @param array $link
 *   The link to be altered.
 */
function printable_link_alter(array &$link) {
  if (printable_preparing_pdf()) {
    $link['options']['absolute'] = TRUE;
  }
}

/**
 * Implements hook_theme_suggestions_alter().
 */
function printable_theme_suggestions_alter(array &$suggestions, array $variables, $hook) {
  if (!printable_preparing_content()) {
    return;
  }
  $additions = [];
  for ($i = 0; $i < count($suggestions); $i++) {
    $additions[$i] = 'printable__' . $suggestions[$i];
  }

  // Prioritise the printable suggestions over normal ones.
  $suggestions = array_merge($suggestions, $additions);
}

Functions

Name	Description
printable_entity_view	Implements hook_entity_view().
printable_entity_view_mode_info_alter	Implements hook_entity_view_mode_alter().
printable_file_url_alter	Make file urls absolute if we're generating a PDF.
printable_help	Implements hook_help().
printable_link_alter	Make Link URLs absolute if we're generating a PDF.
printable_permission	Implements hook_permission().
printable_preparing_content	Are we in the process of generating a printable version of content?
printable_preparing_pdf	Are we in the process of generating a PDF?
printable_theme	Implements hook_theme().
printable_theme_suggestions_alter	Implements hook_theme_suggestions_alter().
template_preprocess_printable	Preprocess variables for list of printable printer friendly page.
template_preprocess_printable_footer	Preprocess variables for list of printable printer friendly page.