field.module 32.5 KB
Newer Older
1 2 3
<?php
/**
 * @file
4
 * Attach custom data fields to Drupal entities.
5 6
 */

7
use Drupal\Core\Entity\EntityInterface;
8
use Drupal\Core\Template\Attribute;
9
use Drupal\field\FieldInterface;
10
use Drupal\field\FieldInstanceInterface;
11

12
/*
13 14 15
 * Load all public Field API functions. Drupal currently has no
 * mechanism for auto-loading core APIs, so we have to load them on
 * every page request.
16
 */
17 18 19 20
require_once __DIR__ . '/field.info.inc';
require_once __DIR__ . '/field.multilingual.inc';
require_once __DIR__ . '/field.attach.inc';
require_once __DIR__ . '/field.form.inc';
21 22
require_once __DIR__ . '/field.purge.inc';
require_once __DIR__ . '/field.deprecated.inc';
23

24 25 26
/**
 * @defgroup field Field API
 * @{
27 28 29 30 31 32 33 34
 * Attaches custom data fields to Drupal entities.
 *
 * The Field API allows custom data fields to be attached to Drupal entities and
 * takes care of storing, loading, editing, and rendering field data. Any entity
 * type (node, user, etc.) can use the Field API to make itself "fieldable" and
 * thus allow fields to be attached to it. Other modules can provide a user
 * interface for managing custom fields via a web browser as well as a wide and
 * flexible variety of data type, form element, and display format capabilities.
35
 *
36 37 38 39 40 41 42 43 44 45 46 47
 * The Field API defines two primary data structures, Field and Instance, and
 * the concept of a Bundle. A Field defines a particular type of data that can
 * be attached to entities. A Field Instance is a Field attached to a single
 * Bundle. A Bundle is a set of fields that are treated as a group by the Field
 * Attach API and is related to a single fieldable entity type.
 *
 * For example, suppose a site administrator wants Article nodes to have a
 * subtitle and photo. Using the Field API or Field UI module, the administrator
 * creates a field named 'subtitle' of type 'text' and a field named 'photo' of
 * type 'image'. The administrator (again, via a UI) creates two Field
 * Instances, one attaching the field 'subtitle' to the 'node' bundle 'article'
 * and one attaching the field 'photo' to the 'node' bundle 'article'. When the
48
 * node storage controller loads an Article node, it loads the values of the
49 50
 * 'subtitle' and 'photo' fields because they are both attached to the 'node'
 * bundle 'article'.
51
 *
52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71
 * - @link field_types Field Types API @endlink: Defines field types, widget
 *   types, and display formatters. Field modules use this API to provide field
 *   types like Text and Node Reference along with the associated form elements
 *   and display formatters.
 *
 * - @link field_crud Field CRUD API @endlink: Create, updates, and deletes
 *   fields, bundles (a.k.a. "content types"), and instances. Modules use this
 *   API, often in hook_install(), to create custom data structures.
 *
 * - @link field_attach Field Attach API @endlink: Connects entity types to the
 *   Field API. Field Attach API functions load, store, generate Form API
 *   structures, display, and perform a variety of other functions for field
 *   data connected to individual entities. Fieldable entity types like node and
 *   user use this API to make themselves fieldable.
 *
 * - @link field_info Field Info API @endlink: Exposes information about all
 *   fields, instances, widgets, and related information defined by or with the
 *   Field API.
 *
 * - @link field_purge Field API bulk data deletion @endlink: Cleans up after
72
 *   bulk deletion operations such as deletion of field or field_instance.
73 74
 *
 * - @link field_language Field language API @endlink: Provides native
75
 *   multilingual support for the Field API.
76 77 78
 */

/**
79
 * Value for field API indicating a field accepts an unlimited number of values.
80
 */
81
const FIELD_CARDINALITY_UNLIMITED = -1;
82 83

/**
84 85 86
 * Value for field API indicating a widget doesn't accept default values.
 *
 * @see hook_field_widget_info()
87
 */
88
const FIELD_BEHAVIOR_NONE = 0x0001;
89

90
/**
91 92 93 94 95 96 97 98
 * Value for field API concerning widget default and multiple value settings.
 *
 * @see hook_field_widget_info()
 *
 * When used in a widget default context, indicates the widget accepts default
 * values. When used in a multiple value context for a widget that allows the
 * input of one single field value, indicates that the widget will be repeated
 * for each value input.
99
 */
100
const FIELD_BEHAVIOR_DEFAULT = 0x0002;
101

102
/**
103 104 105
 * Value for field API indicating a widget can receive several field values.
 *
 * @see hook_field_widget_info()
106
 */
107
const FIELD_BEHAVIOR_CUSTOM = 0x0004;
108 109

/**
110
 * Implements hook_help().
111 112 113 114
 */
function field_help($path, $arg) {
  switch ($path) {
    case 'admin/help#field':
115 116
      $output = '';
      $output .= '<h3>' . t('About') . '</h3>';
117
      $output .= '<p>' . t('The Field module allows custom data fields to be defined for <em>entity</em> types (entities include content items, comments, user accounts, and taxonomy terms). The Field module takes care of storing, loading, editing, and rendering field data. Most users will not interact with the Field module directly, but will instead use the <a href="@field-ui-help">Field UI module</a> user interface. Module developers can use the Field API to make new entity types "fieldable" and thus allow fields to be attached to them. For more information, see the online handbook entry for <a href="@field">Field module</a>.', array('@field-ui-help' => url('admin/help/field_ui'), '@field' => 'http://drupal.org/documentation/modules/field')) . '</p>';
118 119 120
      $output .= '<h3>' . t('Uses') . '</h3>';
      $output .= '<dl>';
      $output .= '<dt>' . t('Enabling field types') . '</dt>';
121
      $output .= '<dd>' . t('The Field module provides the infrastructure for fields and field attachment; the field types and input widgets themselves are provided by additional modules. Some of the modules are required; the optional modules can be enabled from the <a href="@modules">Modules administration page</a>. Drupal core includes the following field type modules: Number (required), Text (required), List (required), Taxonomy (optional), Image (optional), and File (optional); the required Options module provides input widgets for other field modules. Additional fields and widgets may be provided by contributed modules, which you can find in the <a href="@contrib">contributed module section of Drupal.org</a>. Currently enabled field and input widget modules:', array('@modules' => url('admin/modules'), '@contrib' => 'http://drupal.org/project/modules', '@options' => url('admin/help/options')));
122

123 124
      // Make a list of all widget and field modules currently enabled, ordered
      // by displayed module name (module names are not translated).
125 126
      $items = array();
      $info = system_get_info('module');
127 128 129 130 131
      $field_widgets = \Drupal::service('plugin.manager.field.widget')->getDefinitions();
      $field_types = \Drupal::service('plugin.manager.entity.field.field_type')->getDefinitions();
      foreach (array_merge($field_types, $field_widgets) as $field_module) {
        $modules[] = $field_module['provider'];
      }
132 133 134 135
      $modules = array_unique($modules);
      sort($modules);
      foreach ($modules as $module) {
        $display = $info[$module]['name'];
136
        if (\Drupal::moduleHandler()->implementsHook($module, 'help')) {
137
          $items[] = l($display, 'admin/help/' . $module);
138 139
        }
        else {
140
          $items[] = $display;
141 142
        }
      }
143 144
      $item_list = array(
        '#theme' => 'item_list',
145
        '#items' => $items,
146
      );
147
      $output .= drupal_render($item_list);
148 149 150 151 152
      return $output;
  }
}

/**
153
 * Implements hook_theme().
154 155
 */
function field_theme() {
156
  return array(
157
    'field' => array(
158
      'render element' => 'element',
159 160
    ),
    'field_multiple_value_form' => array(
161
      'render element' => 'element',
162 163 164 165
    ),
  );
}

166
/**
167
 * Implements hook_cron().
168 169
 */
function field_cron() {
170
  // Refresh the 'active' status of fields.
171
  field_sync_field_status();
172 173

  // Do a pass of purging on deleted Field API data, if any exists.
174
  $limit = \Drupal::config('field.settings')->get('purge_batch_size');
175 176 177
  field_purge_batch($limit);
}

178
/**
179 180
 * Implements hook_system_info_alter().
 *
181
 * Goes through a list of all modules that provide a field type and makes them
182
 * required if there are any active fields of that type.
183
 */
184
function field_system_info_alter(&$info, $file, $type) {
185
  // It is not safe to call field_read_fields() during maintenance mode.
186
  if ($type == 'module' && !defined('MAINTENANCE_MODE')) {
187 188 189 190 191 192 193 194
    $fields = field_read_fields(array('module' => $file->name), array('include_deleted' => TRUE));
    if ($fields) {
      $info['required'] = TRUE;

      // Provide an explanation message (only mention pending deletions if there
      // remains no actual, non-deleted fields)
      $non_deleted = FALSE;
      foreach ($fields as $field) {
195
        if (empty($field->deleted)) {
196 197 198 199 200 201
          $non_deleted = TRUE;
          break;
        }
      }
      if ($non_deleted) {
        if (module_exists('field_ui')) {
202
          $explanation = t('Field type(s) in use - see <a href="@fields-page">Field list</a>', array('@fields-page' => url('admin/reports/fields')));
203 204 205 206 207 208 209 210 211 212
        }
        else {
          $explanation = t('Fields type(s) in use');
        }
      }
      else {
        $explanation = t('Fields pending deletion');
      }
      $info['explanation'] = $explanation;
    }
213 214 215
  }
}

216 217 218 219 220 221 222 223 224 225
/**
 * Implements hook_entity_field_info() to define all configured fields.
 */
function field_entity_field_info($entity_type) {
  $property_info = array();

  foreach (field_info_instances($entity_type) as $bundle_name => $instances) {
    $optional = $bundle_name != $entity_type;

    foreach ($instances as $field_name => $instance) {
226
      $definition = _field_generate_entity_field_definition($instance->getField());
227

228 229 230 231 232 233
      if ($optional) {
        $property_info['optional'][$field_name] = $definition;
        $property_info['bundle map'][$bundle_name][] = $field_name;
      }
      else {
        $property_info['definitions'][$field_name] = $definition;
234 235 236 237 238 239 240
      }
    }
  }

  return $property_info;
}

241 242 243 244 245 246 247 248 249 250 251 252 253 254
/**
 * Generates an entity field definition for a configurable field.
 *
 * @param \Drupal\field\FieldInterface $field
 *   The field definition.
 * @param \Drupal\field\FieldInstanceInterface $instance
 *   (Optional) The field instance definition.
 *
 * @return array
 *   The entity field definition.
 */
function _field_generate_entity_field_definition(FieldInterface $field, FieldInstanceInterface $instance = NULL) {
  // @todo: Allow for adding field type settings.
  $definition = array(
255
    'label' => t('Field !name', array('!name' => $field->name)),
256 257 258 259 260 261 262 263 264 265 266 267
    'type' => 'field_item:' . $field->type,
    'list' => TRUE,
    'configurable' => TRUE,
    'translatable' => !empty($field->translatable),
  );
  if ($instance) {
    $definition['instance'] = $instance;
  }

  return $definition;
}

268 269 270 271 272
/**
 * Implements hook_field_widget_info_alter().
 */
function field_field_widget_info_alter(&$info) {
  // Add the Hidden widget to all field types.
273
  $info['hidden']['field_types'] = array_keys(\Drupal::service('plugin.manager.entity.field.field_type')->getDefinitions());
274 275
}

276
/**
277
 * Implements hook_entity_bundle_create().
278
 */
279 280 281 282
function field_entity_bundle_create($entity_type, $bundle) {
  // Clear the cache.
  field_cache_clear();
}
283

284 285 286 287 288 289 290
/**
 * Implements hook_entity_bundle_rename().
 */
function field_entity_bundle_rename($entity_type, $bundle_old, $bundle_new) {
  $instances = field_read_instances();
  foreach ($instances as $instance) {
    if ($instance->entity_type == $entity_type && $instance->bundle == $bundle_old) {
291
      $id_new = $instance->entity_type . '.' . $bundle_new . '.' . $instance->getFieldName();
292 293 294 295
      $instance->id = $id_new;
      $instance->bundle = $bundle_new;
      $instance->allowBundleRename();
      $instance->save();
296 297
    }
  }
298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323

  // Clear the field cache.
  field_cache_clear();
}

/**
 * Implements hook_entity_bundle_delete().
 *
 * This deletes the data for the field instances as well as the field instances
 * themselves. This function actually just marks the data and field instances as
 * deleted, leaving the garbage collection for a separate process, because it is
 * not always possible to delete this much data in a single page request
 * (particularly since for some field types, the deletion is more than just a
 * simple DELETE query).
 */
function field_entity_bundle_delete($entity_type, $bundle) {
  // Get the instances on the bundle. field_read_instances() must be used
  // here since field_info_instances() does not return instances for disabled
  // entity types or bundles.
  $instances = field_read_instances(array('entity_type' => $entity_type, 'bundle' => $bundle), array('include_inactive' => TRUE));
  foreach ($instances as $instance) {
    $instance->delete();
  }

  // Clear the cache.
  field_cache_clear();
324 325
}

326 327 328 329
/**
 * Implements hook_rebuild().
 */
function field_rebuild() {
330
  // Refresh the 'active' status of fields.
331 332 333
  field_sync_field_status();
}

334
/**
335
 * Implements hook_modules_installed().
336
 */
337
function field_modules_installed($modules) {
338 339 340 341 342
  // Refresh the 'active' status of fields.
  field_sync_field_status();
}

/**
343
 * Implements hook_modules_uninstalled().
344
 */
345
function field_modules_uninstalled($modules) {
346 347 348 349
  // Refresh the 'active' status of fields.
  field_sync_field_status();
}

350
/**
351
 * Refreshes the 'active' and 'storage[active]' values for fields.
352 353
 */
function field_sync_field_status() {
354 355
  $module_handler = \Drupal::moduleHandler();
  $state = \Drupal::state();
356 357 358

  // Get both deleted and non-deleted field definitions.
  $fields = array();
359
  foreach (config_get_storage_names_with_prefix('field.field.') as $name) {
360
    $field = \Drupal::config($name)->get();
361
    $fields[$field['uuid']] = $field;
362
  }
363 364
  $deleted_fields = $state->get('field.field.deleted') ?: array();
  $fields += $deleted_fields;
365

366 367
  if (empty($fields)) {
    return;
368
  }
369 370 371 372 373

  // Set the 'module' and 'active' values for the current set of enabled
  // modules.
  $changed = array();
  $modules = $module_handler->getModuleList();
374
  $field_types = \Drupal::service('plugin.manager.entity.field.field_type')->getDefinitions();
375
  // Set fields with missing field type modules to inactive.
376
  foreach ($fields as $uuid => &$field) {
377
    // Associate field types.
378 379
    if (isset($field_types[$field['type']]) && ($field['module'] != $field_types[$field['type']]['provider'] || !$field['active'])) {
      $field['module'] = $field_types[$field['type']]['provider'];
380 381 382
      $field['active'] = TRUE;
      $changed[$uuid] = $field;
    }
383 384 385 386 387 388 389 390 391 392 393 394
    if (!isset($modules[$field['module']]) && $field['active']) {
      $field['active'] = FALSE;
      $changed[$uuid] = $field;
    }
  }

  // Store the updated field definitions.
  foreach ($changed as $uuid => $field) {
    if (!empty($field['deleted'])) {
      $deleted_fields[$uuid] = $field;
    }
    else {
395
      \Drupal::config('field.field.' . $field['id'])
396 397 398 399 400 401 402 403
        ->set('module', $field['module'])
        ->set('active', $field['active'])
        ->save();
    }
  }
  $state->set('field.field.deleted', $deleted_fields);

  field_cache_clear();
404 405 406
}

/**
407
 * Clears the field info and field data caches.
408
 */
409
function field_cache_clear() {
410
  cache('field')->deleteAll();
411
  field_info_cache_clear();
412 413 414
}

/**
415 416
 * Filters an HTML string to prevent cross-site-scripting (XSS) vulnerabilities.
 *
417 418
 * Like filter_xss_admin(), but with a shorter list of allowed tags.
 *
419 420 421 422 423 424 425 426 427 428
 * Used for items entered by administrators, like field descriptions, allowed
 * values, where some (mainly inline) mark-up may be desired (so
 * drupal_htmlspecialchars() is not acceptable).
 *
 * @param $string
 *   The string with raw HTML in it.
 *
 * @return
 *   An XSS safe version of $string, or an empty string if $string is not valid
 *   UTF-8.
429 430
 */
function field_filter_xss($string) {
431
  return _filter_htmlcorrector(filter_xss($string, _field_filter_xss_allowed_tags()));
432 433 434
}

/**
435
 * Returns a list of tags allowed by field_filter_xss().
436 437 438 439 440 441
 */
function _field_filter_xss_allowed_tags() {
  return array('a', 'b', 'big',  'code', 'del', 'em', 'i', 'ins',  'pre', 'q', 'small', 'span', 'strong', 'sub', 'sup', 'tt', 'ol', 'ul', 'li', 'p', 'br', 'img');
}

/**
442
 * Returns a human-readable list of allowed tags for display in help texts.
443 444 445 446 447 448
 */
function _field_filter_xss_display_allowed_tags() {
  return '<' . implode('> <', _field_filter_xss_allowed_tags()) . '>';
}

/**
449
 * Returns a renderable array for a single field value.
450
 *
451
 * @param \Drupal\Core\Entity\EntityInterface $entity
452
 *   The entity containing the field to display. Must at least contain the ID
453 454 455
 *   key and the field data to display.
 * @param $field_name
 *   The name of the field to display.
456
 * @param $item
457
 *   The field item value to display.
458
 * @param $display
459 460
 *   Can be either the name of a view mode, or an array of display settings. See
 *   field_view_field() for more information.
461
 * @param $langcode
462 463 464
 *   (Optional) The language of the value in $item. If not provided, the current
 *   language will be assumed.
 *
465
 * @return
466
 *   A renderable array for the field value.
467
 */
468
function field_view_value(EntityInterface $entity, $field_name, $item, $display = array(), $langcode = NULL) {
469
  $output = array();
470

471
  if ($field = field_info_field($entity->entityType(), $field_name)) {
472
    // Determine the langcode that will be used by language fallback.
473
    $langcode = field_language($entity, $field_name, $langcode);
474

475 476 477
    // Push the item as the single value for the field, and defer to
    // field_view_field() to build the render array for the whole field.
    $clone = clone $entity;
478
    $clone->getTranslation($langcode)->{$field_name}->setValue(array($item));
479
    $elements = field_view_field($clone, $field_name, $display, $langcode);
480

481 482 483 484
    // Extract the part of the render array we need.
    $output = isset($elements[0]) ? $elements[0] : array();
    if (isset($elements['#access'])) {
      $output['#access'] = $elements['#access'];
485 486
    }
  }
487 488

  return $output;
489 490 491
}

/**
492
 * Returns a renderable array for the value of a single field in an entity.
493
 *
494
 * The resulting output is a fully themed field with label and multiple values.
495
 *
496 497
 * This function can be used by third-party modules that need to output an
 * isolated field.
498
 * - Do not use inside node (or any other entity) templates; use
499
 *   render($content[FIELD_NAME]) instead.
500
 * - Do not use to display all fields in an entity; use
501
 *   field_attach_prepare_view() and field_attach_view() instead.
502 503
 * - The field_view_value() function can be used to output a single formatted
 *   field value, without label or wrapping field markup.
504
 *
505 506 507
 * The function takes care of invoking the prepare_view steps. It also respects
 * field access permissions.
 *
508 509
 * @param \Drupal\Core\Entity\EntityInterface $entity
 *   The entity containing the field to display.
510 511
 * @param $field_name
 *   The name of the field to display.
512
 * @param $display_options
513
 *   Can be either:
514 515
 *   - The name of a view mode. The field will be displayed according to the
 *     display settings specified for this view mode in the $instance
516 517 518
 *     definition for the field in the entity's bundle. If no display settings
 *     are found for the view mode, the settings for the 'default' view mode
 *     will be used.
519
 *   - An array of display options. The following key/value pairs are allowed:
520 521 522 523
 *     - label: (string) Position of the label. The default 'field' theme
 *       implementation supports the values 'inline', 'above' and 'hidden'.
 *       Defaults to 'above'.
 *     - type: (string) The formatter to use. Defaults to the
524 525
 *       'default_formatter' for the field type. The default formatter will also
 *       be used if the requested formatter is not available.
526
 *     - settings: (array) Settings specific to the formatter. Defaults to the
527
 *       formatter's default settings.
528 529 530
 *     - weight: (float) The weight to assign to the renderable element.
 *       Defaults to 0.
 * @param $langcode
531 532
 *   (Optional) The language code the field values are to be shown in. The
 *   site's current language fallback logic will be applied when no values are
533
 *   available for the given language code. If no language code is provided the
534
 *   current language will be used.
535
 *
536
 * @return
537
 *   A renderable array for the field value.
538 539
 *
 * @see field_view_value()
540
 */
541
function field_view_field(EntityInterface $entity, $field_name, $display_options = array(), $langcode = NULL) {
542
  $output = array();
543
  $bundle = $entity->bundle();
544
  $entity_type = $entity->entityType();
545

546
  // Return nothing if the field doesn't exist.
547
  $instance = field_info_instance($entity_type, $field_name, $bundle);
548 549 550 551 552 553 554
  if (!$instance) {
    return $output;
  }

  // Get the formatter object.
  if (is_string($display_options)) {
    $view_mode = $display_options;
555
    $formatter = entity_get_render_display($entity, $view_mode)->getRenderer($field_name);
556 557 558 559 560
  }
  else {
    $view_mode = '_custom';
    // hook_field_attach_display_alter() needs to receive the 'prepared'
    // $display_options, so we cannot let preparation happen internally.
561
    $field = field_info_field($entity_type, $field_name);
562
    $formatter_manager = drupal_container()->get('plugin.manager.field.formatter');
563
    $display_options = $formatter_manager->prepareConfiguration($field->getFieldType(), $display_options);
564
    $formatter = $formatter_manager->getInstance(array(
565
      'field_definition' => $instance,
566 567 568 569 570 571 572
      'view_mode' => $view_mode,
      'prepare' => FALSE,
      'configuration' => $display_options,
    ));
  }

  if ($formatter) {
573
    $display_langcode = field_language($entity, $field_name, $langcode);
574

575
    // Invoke the formatter's prepareView() and view() methods.
576
    $items = $entity->getTranslation($display_langcode)->get($field_name);
577 578
    $formatter->prepareView(array($entity->id() => $items));
    $result = $formatter->view($items);
579

580 581 582 583 584 585
    // Invoke hook_field_attach_view_alter() to let other modules alter the
    // renderable array, as in a full field_attach_view() execution.
    $context = array(
      'entity' => $entity,
      'view_mode' => $view_mode,
      'display_options' => $display_options,
586
      'langcode' => $display_langcode,
587 588
    );
    drupal_alter('field_attach_view', $result, $context);
589

590 591
    if (isset($result[$field_name])) {
      $output = $result[$field_name];
592
    }
593
  }
594

595 596 597
  return $output;
}

598
/**
599
 * Extracts the bundle name from a bundle object.
600
 *
601
 * @param $entity_type
602
 *   The type of $entity; e.g., 'node' or 'user'.
603
 * @param $bundle
604
 *   The bundle object (or string if bundles for this entity type do not exist
605
 *   as standalone objects).
606
 *
607 608 609
 * @return
 *   The bundle name.
 */
610
function field_extract_bundle($entity_type, $bundle) {
611 612 613 614
  if (is_string($bundle)) {
    return $bundle;
  }

615
  $info = entity_get_info($entity_type);
616 617
  if (is_object($bundle) && isset($info['bundle_keys']['bundle']) && isset($bundle->{$info['bundle_keys']['bundle']})) {
    return $bundle->{$info['bundle_keys']['bundle']};
618 619 620
  }
}

621 622 623 624 625
/**
 * Implements hook_page_build().
 */
function field_page_build(&$page) {
  $path = drupal_get_path('module', 'field');
626
  $page['#attached']['css'][$path . '/css/field.module.css'] = array('every_page' => TRUE);
627 628
}

629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644
/**
 * Implements hook_theme_suggestions_HOOK().
 */
function field_theme_suggestions_field(array $variables) {
  $suggestions = array();
  $element = $variables['element'];

  $suggestions[] = 'field__' . $element['#field_type'];
  $suggestions[] = 'field__' . $element['#field_name'];
  $suggestions[] = 'field__' . $element['#entity_type'] . '__' . $element['#bundle'];
  $suggestions[] = 'field__' . $element['#entity_type'] . '__' . $element['#field_name'];
  $suggestions[] = 'field__' . $element['#entity_type'] . '__' . $element['#field_name'] . '__' . $element['#bundle'];

  return $suggestions;
}

645
/**
646
 * Prepares variables for field templates.
647
 *
648 649 650 651 652 653 654 655 656
 * Default template: field.html.twig.
 *
 * @param array $variables
 *   An associative array containing:
 *   - element: A render element representing the field.
 *   - attributes: A string containing the attributes for the wrapping div.
 *   - title_attributes: A string containing the attributes for the title.
 *   - content_attributes: A string containing the attributes for the content's
 *     div.
657
 */
658
function template_preprocess_field(&$variables, $hook) {
659 660
  $element = $variables['element'];

661 662 663 664 665 666 667 668 669 670 671
  // There's some overhead in calling check_plain() so only call it if the label
  // variable is being displayed. Otherwise, set it to NULL to avoid PHP
  // warnings if a theme implementation accesses the variable even when it's
  // supposed to be hidden. If a theme implementation needs to print a hidden
  // label, it needs to supply a preprocess function that sets it to the
  // sanitized element title or whatever else is wanted in its place.
  $variables['label_hidden'] = ($element['#label_display'] == 'hidden');
  $variables['label'] = $variables['label_hidden'] ? NULL : check_plain($element['#title']);

  // We want other preprocess functions and the theme implementation to have
  // fast access to the field item render arrays. The item render array keys
672 673 674 675
  // (deltas) should always be numerically indexed starting from 0, and looping
  // on those keys is faster than calling element_children() or looping on all
  // keys within $element, since that requires traversal of all element
  // properties.
676
  $variables['items'] = array();
677 678 679 680
  $delta = 0;
  while (!empty($element[$delta])) {
    $variables['items'][$delta] = $element[$delta];
    $delta++;
681 682 683 684 685
  }

  // Add default CSS classes. Since there can be many fields rendered on a page,
  // save some overhead by calling strtr() directly instead of
  // drupal_html_class().
686
  $variables['entity_type_css'] = strtr($element['#entity_type'], '_', '-');
687 688
  $variables['field_name_css'] = strtr($element['#field_name'], '_', '-');
  $variables['field_type_css'] = strtr($element['#field_type'], '_', '-');
689
  $variables['attributes']['class'] = array(
690
    'field',
691
    'field-' . $variables['entity_type_css'] . '--' . $variables['field_name_css'],
692 693 694
    'field-name-' . $variables['field_name_css'],
    'field-type-' . $variables['field_type_css'],
    'field-label-' . $element['#label_display'],
695
  );
696
  // Add a "clearfix" class to the wrapper since we float the label and the
697
  // field items in field.module.css if the label is inline.
698
  if ($element['#label_display'] == 'inline') {
699
    $variables['attributes']['class'][] = 'clearfix';
700
  }
701

702 703
  static $default_attributes;
  if (!isset($default_attributes)) {
704
    $default_attributes = new Attribute;
705
  }
706 707 708 709 710 711 712
  // The default theme implementation for fields is a function.
  // template_preprocess() (which initializes the attributes, title_attributes,
  // and content_attributes arrays) does not run for theme function
  // implementations. Additionally, Attribute objects for the three variables
  // below only get instantiated for template file implementations, and we need
  // Attribute objects for printing in both theme functions and template files.
  // For best performance, we only instantiate Attribute objects when needed.
713 714 715
  $variables['attributes'] = isset($variables['attributes']) ? new Attribute($variables['attributes']) : clone $default_attributes;
  $variables['title_attributes'] = isset($variables['title_attributes']) ? new Attribute($variables['title_attributes']) : clone($default_attributes);
  $variables['content_attributes'] = isset($variables['content_attributes']) ? new Attribute($variables['content_attributes']) : clone($default_attributes);
716 717 718 719 720 721 722 723

  // Modules (e.g., rdf.module) can add field item attributes (to
  // $item->_attributes) within hook_entity_prepare_view(). Some field
  // formatters move those attributes into some nested formatter-specific
  // element in order have them rendered on the desired HTML element (e.g., on
  // the <a> element of a field item being rendered as a link). Other field
  // formatters leave them within $element['#items'][$delta]['_attributes'] to
  // be rendered on the item wrappers provided by theme_field().
724
  foreach ($variables['items'] as $delta => $item) {
725
    $variables['item_attributes'][$delta] = !empty($element['#items'][$delta]['_attributes']) ? new Attribute($element['#items'][$delta]['_attributes']) : clone($default_attributes);
726 727
  }
}
728

729
/**
730
 * @} End of "defgroup field".
731
 */
732 733

/**
734
 * Returns HTML for a field.
735 736 737 738 739 740 741 742 743 744 745 746 747 748
 *
 * This is the default theme implementation to display the value of a field.
 * Theme developers who are comfortable with overriding theme functions may do
 * so in order to customize this markup. This function can be overridden with
 * varying levels of specificity. For example, for a field named 'body'
 * displayed on the 'article' content type, any of the following functions will
 * override this default implementation. The first of these functions that
 * exists is used:
 * - THEMENAME_field__body__article()
 * - THEMENAME_field__article()
 * - THEMENAME_field__body()
 * - THEMENAME_field()
 *
 * Theme developers who prefer to customize templates instead of overriding
749 750
 * functions may copy the "field.html.twig" from the "modules/field/theme"
 * folder of the Drupal installation to somewhere within the theme's folder and
751
 * customize it, just like customizing other Drupal templates such as
752
 * page.html.twig or node.html.twig. However, it takes longer for the server to
753 754
 * process templates than to call a function, so for websites with many fields
 * displayed on a page, this can result in a noticeable slowdown of the website.
755
 * For these websites, developers are discouraged from placing a field.html.twig
756 757 758 759
 * file into the theme's folder, but may customize templates for specific
 * fields. For example, for a field named 'body' displayed on the 'article'
 * content type, any of the following templates will override this default
 * implementation. The first of these templates that exists is used:
760 761 762 763
 * - field--body--article.html.twig
 * - field--article.html.twig
 * - field--body.html.twig
 * - field.html.twig
764
 * So, if the body field on the article content type needs customization, a
765
 * field--body--article.html.twig file can be added within the theme's folder.
766
 * Because it's a template, it will result in slightly more time needed to
767 768
 * display that field, but it will not impact other fields, and therefore, is
 * unlikely to cause a noticeable change in website performance. A very rough
769 770 771 772 773 774
 * guideline is that if a page is being displayed with more than 100 fields and
 * they are all themed with a template instead of a function, it can add up to
 * 5% to the time it takes to display that page. This is a guideline only and
 * the exact performance impact depends on the server configuration and the
 * details of the website.
 *
775 776
 * @param $variables
 *   An associative array containing:
777 778
 *   - label_hidden: A boolean indicating whether to show or hide the field
 *     label.
779 780
 *   - title_attributes: A string containing the attributes for the title.
 *   - label: The label for the field.
781
 *   - content_attributes: A string containing the attributes for the content's
782 783 784 785 786 787
 *     div.
 *   - items: An array of field items.
 *   - item_attributes: An array of attributes for each item.
 *   - classes: A string containing the classes for the wrapping div.
 *   - attributes: A string containing the attributes for the wrapping div.
 *
788
 * @see template_preprocess_field()
789
 * @see field.html.twig
790 791 792 793 794 795 796 797
 *
 * @ingroup themeable
 */
function theme_field($variables) {
  $output = '';

  // Render the label, if it's not hidden.
  if (!$variables['label_hidden']) {
798
    $output .= '<div class="field-label"' . $variables['title_attributes'] . '>' . $variables['label'] . '</div>';
799 800 801 802 803 804 805 806 807 808 809
  }

  // Render the items.
  $output .= '<div class="field-items"' . $variables['content_attributes'] . '>';
  foreach ($variables['items'] as $delta => $item) {
    $classes = 'field-item ' . ($delta % 2 ? 'odd' : 'even');
    $output .= '<div class="' . $classes . '"' . $variables['item_attributes'][$delta] . '>' . drupal_render($item) . '</div>';
  }
  $output .= '</div>';

  // Render the top-level DIV.
810
  $output = '<div' . $variables['attributes'] . '>' . $output . '</div>';
811 812 813

  return $output;
}
814 815 816 817 818 819 820 821

/**
 * Assembles a partial entity structure with initial IDs.
 *
 * @param stdClass $ids
 *   An object with the properties entity_type (required), entity_id (required),
 *   revision_id (optional) and bundle (optional).
 *
822
 * @return \Drupal\Core\Entity\EntityInterface
823 824 825 826 827
 *   An entity, initialized with the provided IDs.
 */
function _field_create_entity_from_ids($ids) {
  $id_properties = array();
  $info = entity_get_info($ids->entity_type);
828 829 830
  if (isset($info['entity_keys']['id'])) {
    $id_properties[$info['entity_keys']['id']] = $ids->entity_id;
  }
831 832
  if (!empty($info['entity_keys']['revision']) && isset($ids->revision_id)) {
    $id_properties[$info['entity_keys']['revision']] = $ids->revision_id;
833
  }
834 835
  if (!empty($info['entity_keys']['bundle']) && isset($ids->bundle)) {
    $id_properties[$info['entity_keys']['bundle']] = $ids->bundle;
836 837
  }
  return entity_create($ids->entity_type, $id_properties);
838 839
}

840 841 842 843 844 845 846 847 848 849 850 851 852
/**
 * Implements hook_hook_info().
 */
function field_hook_info() {
  $hooks['field_views_data'] = array(
    'group' => 'views',
  );
  $hooks['field_views_data_alter'] = array(
    'group' => 'views',
  );

  return $hooks;
}