Drupal PHP Cross Reference Content Management Systems

Source: /modules/field/field.attach.inc - 1369 lines - 54400 bytes - Summary - Text - Print

   1  <?php
   2  
   3  /**
   4   * @file
   5   * Field attach API, allowing entities (nodes, users, ...) to be 'fieldable'.
   6   */
   7  
   8  /**
   9   * Exception thrown by field_attach_validate() on field validation errors.
  10   */
  11  class FieldValidationException extends FieldException {
  12    var $errors;
  13  
  14   /**
  15    * Constructor for FieldValidationException.
  16    *
  17    * @param $errors
  18    *   An array of field validation errors, keyed by field name and
  19    *   delta that contains two keys:
  20    *   - 'error': A machine-readable error code string, prefixed by
  21    *     the field module name. A field widget may use this code to decide
  22    *     how to report the error.
  23    *   - 'message': A human-readable error message such as to be
  24    *     passed to form_error() for the appropriate form element.
  25    */
  26    function __construct($errors) {
  27      $this->errors = $errors;
  28      parent::__construct(t('Field validation errors'));
  29    }
  30  }
  31  
  32  /**
  33   * @defgroup field_storage Field Storage API
  34   * @{
  35   * Implement a storage engine for Field API data.
  36   *
  37   * The Field Attach API uses the Field Storage API to perform all "database
  38   * access". Each Field Storage API hook function defines a primitive database
  39   * operation such as read, write, or delete. The default field storage module,
  40   * field_sql_storage.module, uses the local SQL database to implement these
  41   * operations, but alternative field storage backends can choose to represent
  42   * the data in SQL differently or use a completely different storage mechanism
  43   * such as a cloud-based database.
  44   *
  45   * Each field defines which storage backend it uses. The Drupal system variable
  46   * 'field_storage_default' identifies the storage backend used by default.
  47   *
  48   * See @link field Field API @endlink for information about the other parts of
  49   * the Field API.
  50   */
  51  
  52  /**
  53   * Argument for an update operation.
  54   *
  55   * This is used in hook_field_storage_write when updating an
  56   * existing entity.
  57   */
  58  define('FIELD_STORAGE_UPDATE', 'update');
  59  
  60  /**
  61   * Argument for an insert operation.
  62   *
  63   * This is used in hook_field_storage_write when inserting a new entity.
  64   */
  65  define('FIELD_STORAGE_INSERT', 'insert');
  66  
  67  /**
  68   * @} End of "defgroup field_storage".
  69   */
  70  
  71  /**
  72   * @defgroup field_attach Field Attach API
  73   * @{
  74   * Operate on Field API data attached to Drupal entities.
  75   *
  76   * Field Attach API functions load, store, display, generate Field API
  77   * structures, and perform a variety of other functions for field data attached
  78   * to individual entities.
  79   *
  80   * Field Attach API functions generally take $entity_type and $entity arguments
  81   * along with additional function-specific arguments. $entity_type is the type
  82   * of the fieldable entity, such as 'node' or 'user', and $entity is the entity
  83   * itself.
  84   *
  85   * hook_entity_info() is the central place for entity types to define if and
  86   * how Field API should operate on their entity objects. Notably, the
  87   * 'fieldable' property needs to be set to TRUE.
  88   *
  89   * The Field Attach API uses the concept of bundles: the set of fields for a
  90   * given entity is defined on a per-bundle basis. The collection of bundles for
  91   * an entity type is defined its hook_entity_info() implementation. For
  92   * instance, node_entity_info() exposes each node type as its own bundle. This
  93   * means that the set of fields of a node is determined by the node type. The
  94   * Field API reads the bundle name for a given entity from a particular
  95   * property of the entity object, and hook_entity_info() defines which property
  96   * to use. For instance, node_entity_info() specifies:
  97   * @code $info['entity keys']['bundle'] = 'type'@endcode
  98   * This indicates that for a particular node object, the bundle name can be
  99   * found in $node->type. This property can be omitted if the entity type only
 100   * exposes a single bundle (all entities of this type have the same collection
 101   * of fields). This is the case for the 'user' entity type.
 102   *
 103   * Most Field Attach API functions define a corresponding hook function that
 104   * allows any module to act on Field Attach operations for any entity after the
 105   * operation is complete, and access or modify all the field, form, or display
 106   * data for that entity and operation. For example, field_attach_view() invokes
 107   * hook_field_attach_view_alter(). These all-module hooks are distinct from
 108   * those of the Field Types API, such as hook_field_load(), that are only
 109   * invoked for the module that defines a specific field type.
 110   *
 111   * field_attach_load(), field_attach_insert(), and field_attach_update() also
 112   * define pre-operation hooks, e.g. hook_field_attach_pre_load(). These hooks
 113   * run before the corresponding Field Storage API and Field Type API
 114   * operations. They allow modules to define additional storage locations (e.g.
 115   * denormalizing, mirroring) for field data on a per-field basis. They also
 116   * allow modules to take over field storage completely by instructing other
 117   * implementations of the same hook and the Field Storage API itself not to
 118   * operate on specified fields.
 119   *
 120   * The pre-operation hooks do not make the Field Storage API irrelevant. The
 121   * Field Storage API is essentially the "fallback mechanism" for any fields
 122   * that aren't being intercepted explicitly by pre-operation hooks.
 123   *
 124   * @link field_language Field Language API @endlink provides information about
 125   * the structure of field objects.
 126   *
 127   * See @link field Field API @endlink for information about the other parts of
 128   * the Field API.
 129   */
 130  
 131  /**
 132   * Invoke a field hook.
 133   *
 134   * @param $op
 135   *   Possible operations include:
 136   *   - form
 137   *   - validate
 138   *   - presave
 139   *   - insert
 140   *   - update
 141   *   - delete
 142   *   - delete revision
 143   *   - view
 144   *   - prepare translation
 145   * @param $entity_type
 146   *   The type of $entity; e.g. 'node' or 'user'.
 147   * @param $entity
 148   *   The fully formed $entity_type entity.
 149   * @param $a
 150   *   - The $form in the 'form' operation.
 151   *   - The value of $view_mode in the 'view' operation.
 152   *   - Otherwise NULL.
 153   * @param $b
 154   *   - The $form_state in the 'submit' operation.
 155   *   - Otherwise NULL.
 156   * @param $options
 157   *   An associative array of additional options, with the following keys:
 158   *  - 'field_name': The name of the field whose operation should be
 159   *    invoked. By default, the operation is invoked on all the fields
 160   *    in the entity's bundle. NOTE: This option is not compatible with
 161   *    the 'deleted' option; the 'field_id' option should be used
 162   *    instead.
 163   *  - 'field_id': The id of the field whose operation should be
 164   *    invoked. By default, the operation is invoked on all the fields
 165   *    in the entity's' bundles.
 166   *  - 'default': A boolean value, specifying which implementation of
 167   *    the operation should be invoked.
 168   *    - if FALSE (default), the field types implementation of the operation
 169   *      will be invoked (hook_field_[op])
 170   *    - If TRUE, the default field implementation of the field operation
 171   *      will be invoked (field_default_[op])
 172   *    Internal use only. Do not explicitely set to TRUE, but use
 173   *    _field_invoke_default() instead.
 174   *  - 'deleted': If TRUE, the function will operate on deleted fields
 175   *    as well as non-deleted fields. If unset or FALSE, only
 176   *    non-deleted fields are operated on.
 177   *  - 'language': A language code or an array of language codes keyed by field
 178   *    name. It will be used to narrow down to a single value the available
 179   *    languages to act on.
 180   */
 181  function _field_invoke($op, $entity_type, $entity, &$a = NULL, &$b = NULL, $options = array()) {
 182    // Merge default options.
 183    $default_options = array(
 184      'default' => FALSE,
 185      'deleted' => FALSE,
 186      'language' => NULL,
 187    );
 188    $options += $default_options;
 189  
 190    // Determine the list of instances to iterate on.
 191    list(, , $bundle) = entity_extract_ids($entity_type, $entity);
 192    $instances = _field_invoke_get_instances($entity_type, $bundle, $options);
 193  
 194    // Iterate through the instances and collect results.
 195    $return = array();
 196    foreach ($instances as $instance) {
 197      // field_info_field() is not available for deleted fields, so use
 198      // field_info_field_by_id().
 199      $field = field_info_field_by_id($instance['field_id']);
 200      $field_name = $field['field_name'];
 201      $function = $options['default'] ? 'field_default_' . $op : $field['module'] . '_field_' . $op;
 202      if (function_exists($function)) {
 203        // Determine the list of languages to iterate on.
 204        $available_languages = field_available_languages($entity_type, $field);
 205        $languages = _field_language_suggestion($available_languages, $options['language'], $field_name);
 206  
 207        foreach ($languages as $langcode) {
 208          $items = isset($entity->{$field_name}[$langcode]) ? $entity->{$field_name}[$langcode] : array();
 209          $result = $function($entity_type, $entity, $field, $instance, $langcode, $items, $a, $b);
 210          if (isset($result)) {
 211            // For hooks with array results, we merge results together.
 212            // For hooks with scalar results, we collect results in an array.
 213            if (is_array($result)) {
 214              $return = array_merge($return, $result);
 215            }
 216            else {
 217              $return[] = $result;
 218            }
 219          }
 220  
 221          // Populate $items back in the field values, but avoid replacing missing
 222          // fields with an empty array (those are not equivalent on update).
 223          if ($items !== array() || isset($entity->{$field_name}[$langcode])) {
 224            $entity->{$field_name}[$langcode] = $items;
 225          }
 226        }
 227      }
 228    }
 229  
 230    return $return;
 231  }
 232  
 233  /**
 234   * Invoke a field hook across fields on multiple entities.
 235   *
 236   * @param $op
 237   *   Possible operations include:
 238   *   - load
 239   *   - prepare_view
 240   *   For all other operations, use _field_invoke() / field_invoke_default()
 241   *   instead.
 242   * @param $entity_type
 243   *   The type of $entity; e.g. 'node' or 'user'.
 244   * @param $entities
 245   *   An array of entities, keyed by entity id.
 246   * @param $a
 247   *   - The $age parameter in the 'load' operation.
 248   *   - Otherwise NULL.
 249   * @param $b
 250   *   Currently always NULL.
 251   * @param $options
 252   *   An associative array of additional options, with the following keys:
 253   *  - 'field_name': The name of the field whose operation should be
 254   *    invoked. By default, the operation is invoked on all the fields
 255   *    in the entity's bundle. NOTE: This option is not compatible with
 256   *    the 'deleted' option; the 'field_id' option should be used instead.
 257   *  - 'field_id': The id of the field whose operation should be
 258   *    invoked. By default, the operation is invoked on all the fields
 259   *    in the entity's' bundles.
 260   *  - 'default': A boolean value, specifying which implementation of
 261   *    the operation should be invoked.
 262   *    - if FALSE (default), the field types implementation of the operation
 263   *      will be invoked (hook_field_[op])
 264   *    - If TRUE, the default field implementation of the field operation
 265   *      will be invoked (field_default_[op])
 266   *    Internal use only. Do not explicitely set to TRUE, but use
 267   *    _field_invoke_multiple_default() instead.
 268   *  - 'deleted': If TRUE, the function will operate on deleted fields
 269   *    as well as non-deleted fields. If unset or FALSE, only
 270   *    non-deleted fields are operated on.
 271   *  - 'language': A language code or an array of arrays of language codes keyed
 272   *    by entity id and field name. It will be used to narrow down to a single
 273   *    value the available languages to act on.
 274   *
 275   * @return
 276   *   An array of returned values keyed by entity id.
 277   */
 278  function _field_invoke_multiple($op, $entity_type, $entities, &$a = NULL, &$b = NULL, $options = array()) {
 279    // Merge default options.
 280    $default_options = array(
 281      'default' => FALSE,
 282      'deleted' => FALSE,
 283      'language' => NULL,
 284    );
 285    $options += $default_options;
 286    $field_info = field_info_field_by_ids();
 287  
 288    $fields = array();
 289    $grouped_instances = array();
 290    $grouped_entities = array();
 291    $grouped_items = array();
 292    $return = array();
 293  
 294    // Go through the entities and collect the fields on which the hook should be
 295    // invoked.
 296    //
 297    // We group fields by id, not by name, because this function can operate on
 298    // deleted fields which may have non-unique names. However, entities can only
 299    // contain data for a single field for each name, even if that field
 300    // is deleted, so we reference field data via the
 301    // $entity->$field_name property.
 302    foreach ($entities as $entity) {
 303      // Determine the list of instances to iterate on.
 304      list($id, $vid, $bundle) = entity_extract_ids($entity_type, $entity);
 305      $instances = _field_invoke_get_instances($entity_type, $bundle, $options);
 306  
 307      foreach ($instances as $instance) {
 308        $field_id = $instance['field_id'];
 309        $field_name = $instance['field_name'];
 310        $field = $field_info[$field_id];
 311        $function = $options['default'] ? 'field_default_' . $op : $field['module'] . '_field_' . $op;
 312        if (function_exists($function)) {
 313          // Add the field to the list of fields to invoke the hook on.
 314          if (!isset($fields[$field_id])) {
 315            $fields[$field_id] = $field;
 316          }
 317          // Extract the field values into a separate variable, easily accessed
 318          // by hook implementations.
 319          // Unless a language suggestion is provided we iterate on all the
 320          // available languages.
 321          $available_languages = field_available_languages($entity_type, $field);
 322          $language = !empty($options['language'][$id]) ? $options['language'][$id] : $options['language'];
 323          $languages = _field_language_suggestion($available_languages, $language, $field_name);
 324          foreach ($languages as $langcode) {
 325            $grouped_items[$field_id][$langcode][$id] = isset($entity->{$field_name}[$langcode]) ? $entity->{$field_name}[$langcode] : array();
 326            // Group the instances and entities corresponding to the current
 327            // field.
 328            $grouped_instances[$field_id][$langcode][$id] = $instance;
 329            $grouped_entities[$field_id][$langcode][$id] = $entities[$id];
 330          }
 331        }
 332      }
 333      // Initialize the return value for each entity.
 334      $return[$id] = array();
 335    }
 336  
 337    // For each field, invoke the field hook and collect results.
 338    foreach ($fields as $field_id => $field) {
 339      $field_name = $field['field_name'];
 340      $function = $options['default'] ? 'field_default_' . $op : $field['module'] . '_field_' . $op;
 341      // Iterate over all the field translations.
 342      foreach ($grouped_items[$field_id] as $langcode => &$items) {
 343        $entities = $grouped_entities[$field_id][$langcode];
 344        $instances = $grouped_instances[$field_id][$langcode];
 345        $results = $function($entity_type, $entities, $field, $instances, $langcode, $items, $a, $b);
 346        if (isset($results)) {
 347          // Collect results by entity.
 348          // For hooks with array results, we merge results together.
 349          // For hooks with scalar results, we collect results in an array.
 350          foreach ($results as $id => $result) {
 351            if (is_array($result)) {
 352              $return[$id] = array_merge($return[$id], $result);
 353            }
 354            else {
 355              $return[$id][] = $result;
 356            }
 357          }
 358        }
 359      }
 360  
 361      // Populate field values back in the entities, but avoid replacing missing
 362      // fields with an empty array (those are not equivalent on update).
 363      foreach ($grouped_entities[$field_id] as $langcode => $entities) {
 364        foreach ($entities as $id => $entity) {
 365          if ($grouped_items[$field_id][$langcode][$id] !== array() || isset($entity->{$field_name}[$langcode])) {
 366            $entity->{$field_name}[$langcode] = $grouped_items[$field_id][$langcode][$id];
 367          }
 368        }
 369      }
 370    }
 371  
 372    return $return;
 373  }
 374  
 375  /**
 376   * Invoke field.module's version of a field hook.
 377   *
 378   * This function invokes the field_default_[op]() function.
 379   * Use _field_invoke() to invoke the field type implementation,
 380   * hook_field_[op]().
 381   *
 382   * @see _field_invoke()
 383   */
 384  function _field_invoke_default($op, $entity_type, $entity, &$a = NULL, &$b = NULL, $options = array()) {
 385    $options['default'] = TRUE;
 386    return _field_invoke($op, $entity_type, $entity, $a, $b, $options);
 387  }
 388  
 389  /**
 390   * Invoke field.module's version of a field hook on multiple entities.
 391   *
 392   * This function invokes the field_default_[op]() function.
 393   * Use _field_invoke_multiple() to invoke the field type implementation,
 394   * hook_field_[op]().
 395   *
 396   * @see _field_invoke_multiple()
 397   */
 398  function _field_invoke_multiple_default($op, $entity_type, $entities, &$a = NULL, &$b = NULL, $options = array()) {
 399    $options['default'] = TRUE;
 400    return _field_invoke_multiple($op, $entity_type, $entities, $a, $b, $options);
 401  }
 402  
 403  /**
 404   * Helper for _field_invoke(): retrieves a list of instances to operate on.
 405   *
 406   * @param $entity_type
 407   *   The entity type.
 408   * @param $bundle
 409   *   The bundle name.
 410   * @param $options
 411   *   An associative array of options, as provided to _field_invoke(). Only the
 412   *   following keys are considered :
 413   *   - deleted
 414   *   - field_name
 415   *   - field_id
 416   *   See _field_invoke() for details.
 417   *
 418   * @return
 419   *   The array of selected instance definitions.
 420   */
 421  function _field_invoke_get_instances($entity_type, $bundle, $options) {
 422    if ($options['deleted']) {
 423      // Deleted fields are not included in field_info_instances(), and need to
 424      // be fetched from the database with field_read_instances().
 425      $params = array('entity_type' => $entity_type, 'bundle' => $bundle);
 426      if (isset($options['field_id'])) {
 427        // Single-field mode by field id: field_read_instances() does the filtering.
 428        // Single-field mode by field name is not compatible with the 'deleted'
 429        // option.
 430        $params['field_id'] = $options['field_id'];
 431      }
 432      $instances = field_read_instances($params, array('include_deleted' => TRUE));
 433    }
 434    elseif (isset($options['field_name'])) {
 435      // Single-field mode by field name: field_info_instance() does the
 436      // filtering.
 437      $instances = array(field_info_instance($entity_type, $options['field_name'], $bundle));
 438    }
 439    else {
 440      $instances = field_info_instances($entity_type, $bundle);
 441      if (isset($options['field_id'])) {
 442        // Single-field mode by field id: we need to loop on each instance to
 443        // find the right one.
 444        foreach ($instances as $instance) {
 445          if ($instance['field_id'] == $options['field_id']) {
 446            $instances = array($instance);
 447            break;
 448          }
 449        }
 450      }
 451    }
 452  
 453    return $instances;
 454  }
 455  
 456  /**
 457   * Add form elements for all fields for an entity to a form structure.
 458   *
 459   * The form elements for the entity's fields are added by reference as direct
 460   * children in the $form parameter. This parameter can be a full form structure
 461   * (most common case for entity edit forms), or a sub-element of a larger form.
 462   *
 463   * By default, submitted field values appear at the top-level of
 464   * $form_state['values']. A different location within $form_state['values'] can
 465   * be specified by setting the '#parents' property on the incoming $form
 466   * parameter. Because of name clashes, two instances of the same field cannot
 467   * appear within the same $form element, or within the same '#parents' space.
 468   *
 469   * For each call to field_attach_form(), field values are processed by calling
 470   * field_attach_form_validate() and field_attach_submit() on the same $form
 471   * element.
 472   *
 473   * Sample resulting structure in $form:
 474   * @code
 475   *   '#parents' => The location of field values in $form_state['values'],
 476   *   '#entity_type' => The name of the entity type,
 477   *   '#bundle' => The name of the bundle,
 478   *   // One sub-array per field appearing in the entity, keyed by field name.
 479   *   // The structure of the array differs slightly depending on whether the
 480   *   // widget is 'single-value' (provides the input for one field value,
 481   *   // most common case), and will therefore be repeated as many times as
 482   *   // needed, or 'multiple-values' (one single widget allows the input of
 483   *   // several values, e.g checkboxes, select box...).
 484   *   // The sub-array is nested into a $langcode key where $langcode has the
 485   *   // same value of the $langcode parameter above.
 486   *   // The '#language' key holds the same value of $langcode and it is used
 487   *   // to access the field sub-array when $langcode is unknown.
 488   *   'field_foo' => array(
 489   *     '#tree' => TRUE,
 490   *     '#field_name' => The name of the field,
 491   *     '#language' => $langcode,
 492   *     $langcode => array(
 493   *       '#field_name' => The name of the field,
 494   *       '#language' => $langcode,
 495   *       '#field_parents' => The 'parents' space for the field in the form,
 496   *          equal to the #parents property of the $form parameter received by
 497   *          field_attach_form(),
 498   *       '#required' => Whether or not the field is required,
 499   *       '#title' => The label of the field instance,
 500   *       '#description' => The description text for the field instance,
 501   *
 502   *       // Only for 'single' widgets:
 503   *       '#theme' => 'field_multiple_value_form',
 504   *       '#cardinality' => The field cardinality,
 505   *       // One sub-array per copy of the widget, keyed by delta.
 506   *       0 => array(
 507   *         '#entity_type' => The name of the entity type,
 508   *         '#bundle' => The name of the bundle,
 509   *         '#field_name' => The name of the field,
 510   *         '#field_parents' => The 'parents' space for the field in the form,
 511   *            equal to the #parents property of the $form parameter received by
 512   *            field_attach_form(),
 513   *         '#title' => The title to be displayed by the widget,
 514   *         '#default_value' => The field value for delta 0,
 515   *         '#required' => Whether the widget should be marked required,
 516   *         '#delta' => 0,
 517   *         '#columns' => The array of field columns,
 518   *         // The remaining elements in the sub-array depend on the widget.
 519   *         '#type' => The type of the widget,
 520   *         ...
 521   *       ),
 522   *       1 => array(
 523   *         ...
 524   *       ),
 525   *
 526   *       // Only for multiple widgets:
 527   *       '#entity_type' => The name of the entity type,
 528   *       '#bundle' => $instance['bundle'],
 529   *       '#columns'  => array_keys($field['columns']),
 530   *       // The remaining elements in the sub-array depend on the widget.
 531   *       '#type' => The type of the widget,
 532   *       ...
 533   *     ),
 534   *     ...
 535   *   ),
 536   * )
 537   * @endcode
 538   *
 539   * Additionally, some processing data is placed in $form_state, and can be
 540   * accessed by field_form_get_state() and field_form_set_state().
 541   *
 542   * @param $entity_type
 543   *   The type of $entity; e.g. 'node' or 'user'.
 544   * @param $entity
 545   *   The entity for which to load form elements, used to initialize
 546   *   default form values.
 547   * @param $form
 548   *   The form structure to fill in. This can be a full form structure, or a
 549   *   sub-element of a larger form. The #parents property can be set to control
 550   *   the location of submitted field values within $form_state['values']. If
 551   *   not specified, $form['#parents'] is set to an empty array, placing field
 552   *   values at the top-level of $form_state['values'].
 553   * @param $form_state
 554   *   An associative array containing the current state of the form.
 555   * @param $langcode
 556   *   The language the field values are going to be entered, if no language
 557   *   is provided the default site language will be used.
 558   *
 559   * @see field_form_get_state()
 560   * @see field_form_set_state()
 561   */
 562  function field_attach_form($entity_type, $entity, &$form, &$form_state, $langcode = NULL) {
 563    // Set #parents to 'top-level' by default.
 564    $form += array('#parents' => array());
 565  
 566    // If no language is provided use the default site language.
 567    $options = array('language' => field_valid_language($langcode));
 568    $form += (array) _field_invoke_default('form', $entity_type, $entity, $form, $form_state, $options);
 569  
 570    // Add custom weight handling.
 571    list($id, $vid, $bundle) = entity_extract_ids($entity_type, $entity);
 572    $form['#pre_render'][] = '_field_extra_fields_pre_render';
 573    $form['#entity_type'] = $entity_type;
 574    $form['#bundle'] = $bundle;
 575  
 576    // Let other modules make changes to the form.
 577    // Avoid module_invoke_all() to let parameters be taken by reference.
 578    foreach (module_implements('field_attach_form') as $module) {
 579      $function = $module . '_field_attach_form';
 580      $function($entity_type, $entity, $form, $form_state, $langcode);
 581    }
 582  }
 583  
 584  /**
 585   * Loads fields for the current revisions of a group of entities.
 586   *
 587   * Loads all fields for each entity object in a group of a single entity type.
 588   * The loaded field values are added directly to the entity objects.
 589   *
 590   * field_attach_load() is automatically called by the default entity controller
 591   * class, and thus, in most cases, doesn't need to be explicitly called by the
 592   * entity type module.
 593   *
 594   * @param $entity_type
 595   *   The type of $entity; e.g., 'node' or 'user'.
 596   * @param $entities
 597   *   An array of entities for which to load fields, keyed by entity ID.
 598   *   Each entity needs to have its 'bundle', 'id' and (if applicable)
 599   *   'revision' keys filled in. The function adds the loaded field data
 600   *   directly in the entity objects of the $entities array.
 601   * @param $age
 602   *   FIELD_LOAD_CURRENT to load the most recent revision for all
 603   *   fields, or FIELD_LOAD_REVISION to load the version indicated by
 604   *   each entity. Defaults to FIELD_LOAD_CURRENT; use
 605   *   field_attach_load_revision() instead of passing FIELD_LOAD_REVISION.
 606   * @param $options
 607   *   An associative array of additional options, with the following keys:
 608   *   - 'field_id': The field ID that should be loaded, instead of
 609   *     loading all fields, for each entity. Note that returned entities
 610   *     may contain data for other fields, for example if they are read
 611   *     from a cache.
 612   *   - 'deleted': If TRUE, the function will operate on deleted fields
 613   *     as well as non-deleted fields. If unset or FALSE, only
 614   *     non-deleted fields are operated on.
 615   */
 616  function field_attach_load($entity_type, $entities, $age = FIELD_LOAD_CURRENT, $options = array()) {
 617    $field_info = field_info_field_by_ids();
 618    $load_current = $age == FIELD_LOAD_CURRENT;
 619  
 620    // Merge default options.
 621    $default_options = array(
 622      'deleted' => FALSE,
 623    );
 624    $options += $default_options;
 625  
 626    $info = entity_get_info($entity_type);
 627    // Only the most current revision of non-deleted fields for cacheable entity
 628    // types can be cached.
 629    $cache_read = $load_current && $info['field cache'] && empty($options['deleted']);
 630    // In addition, do not write to the cache when loading a single field.
 631    $cache_write = $cache_read && !isset($options['field_id']);
 632  
 633    if (empty($entities)) {
 634      return;
 635    }
 636  
 637    // Assume all entities will need to be queried. Entities found in the cache
 638    // will be removed from the list.
 639    $queried_entities = $entities;
 640  
 641    // Fetch available entities from cache, if applicable.
 642    if ($cache_read) {
 643      // Build the list of cache entries to retrieve.
 644      $cids = array();
 645      foreach ($entities as $id => $entity) {
 646        $cids[] = "field:$entity_type:$id";
 647      }
 648      $cache = cache_get_multiple($cids, 'cache_field');
 649      // Put the cached field values back into the entities and remove them from
 650      // the list of entities to query.
 651      foreach ($entities as $id => $entity) {
 652        $cid = "field:$entity_type:$id";
 653        if (isset($cache[$cid])) {
 654          unset($queried_entities[$id]);
 655          foreach ($cache[$cid]->data as $field_name => $values) {
 656            $entity->$field_name = $values;
 657          }
 658        }
 659      }
 660    }
 661  
 662    // Fetch other entities from their storage location.
 663    if ($queried_entities) {
 664      // The invoke order is:
 665      // - hook_field_storage_pre_load()
 666      // - storage backend's hook_field_storage_load()
 667      // - field-type module's hook_field_load()
 668      // - hook_field_attach_load()
 669  
 670      // Invoke hook_field_storage_pre_load(): let any module load field
 671      // data before the storage engine, accumulating along the way.
 672      $skip_fields = array();
 673      foreach (module_implements('field_storage_pre_load') as $module) {
 674        $function = $module . '_field_storage_pre_load';
 675        $function($entity_type, $queried_entities, $age, $skip_fields, $options);
 676      }
 677  
 678      $instances = array();
 679  
 680      // Collect the storage backends used by the remaining fields in the entities.
 681      $storages = array();
 682      foreach ($queried_entities as $entity) {
 683        list($id, $vid, $bundle) = entity_extract_ids($entity_type, $entity);
 684        $instances = _field_invoke_get_instances($entity_type, $bundle, $options);
 685  
 686        foreach ($instances as $instance) {
 687          $field_name = $instance['field_name'];
 688          $field_id = $instance['field_id'];
 689          // Make sure all fields are present at least as empty arrays.
 690          if (!isset($queried_entities[$id]->{$field_name})) {
 691            $queried_entities[$id]->{$field_name} = array();
 692          }
 693          // Collect the storage backend if the field has not been loaded yet.
 694          if (!isset($skip_fields[$field_id])) {
 695            $field = $field_info[$field_id];
 696            $storages[$field['storage']['type']][$field_id][] = $load_current ? $id : $vid;
 697          }
 698        }
 699      }
 700  
 701      // Invoke hook_field_storage_load() on the relevant storage backends.
 702      foreach ($storages as $storage => $fields) {
 703        $storage_info = field_info_storage_types($storage);
 704        module_invoke($storage_info['module'], 'field_storage_load', $entity_type, $queried_entities, $age, $fields, $options);
 705      }
 706  
 707      // Invoke field-type module's hook_field_load().
 708      $null = NULL;
 709      _field_invoke_multiple('load', $entity_type, $queried_entities, $age, $null, $options);
 710  
 711      // Invoke hook_field_attach_load(): let other modules act on loading the
 712      // entitiy.
 713      module_invoke_all('field_attach_load', $entity_type, $queried_entities, $age, $options);
 714  
 715      // Build cache data.
 716      if ($cache_write) {
 717        foreach ($queried_entities as $id => $entity) {
 718          $data = array();
 719          list($id, $vid, $bundle) = entity_extract_ids($entity_type, $entity);
 720          $instances = field_info_instances($entity_type, $bundle);
 721          foreach ($instances as $instance) {
 722            $data[$instance['field_name']] = $queried_entities[$id]->{$instance['field_name']};
 723          }
 724          $cid = "field:$entity_type:$id";
 725          cache_set($cid, $data, 'cache_field');
 726        }
 727      }
 728    }
 729  }
 730  
 731  /**
 732   * Load all fields for previous versions of a group of entities.
 733   *
 734   * Loading different versions of the same entities is not supported, and should
 735   * be done by separate calls to the function.
 736   *
 737   * field_attach_load_revision() is automatically called by the default entity
 738   * controller class, and thus, in most cases, doesn't need to be explicitly
 739   * called by the entity type module.
 740   *
 741   * @param $entity_type
 742   *   The type of $entity; e.g. 'node' or 'user'.
 743   * @param $entities
 744   *   An array of entities for which to load fields, keyed by entity ID. Each
 745   *   entity needs to have its 'bundle', 'id' and (if applicable) 'revision'
 746   *   keys filled. The function adds the loaded field data directly in the
 747   *   entity objects of the $entities array.
 748   * @param $options
 749   *   An associative array of additional options. See field_attach_load() for
 750   *   details.
 751   */
 752  function field_attach_load_revision($entity_type, $entities, $options = array()) {
 753    return field_attach_load($entity_type, $entities, FIELD_LOAD_REVISION, $options);
 754  }
 755  
 756  /**
 757   * Perform field validation against the field data in an entity.
 758   *
 759   * This function does not perform field widget validation on form
 760   * submissions. It is intended to be called during API save
 761   * operations. Use field_attach_form_validate() to validate form
 762   * submissions.
 763   *
 764   * @param $entity_type
 765   *   The type of $entity; e.g. 'node' or 'user'.
 766   * @param $entity
 767   *   The entity with fields to validate.
 768   * @throws FieldValidationException
 769   *   If validation errors are found, a FieldValidationException is thrown. The
 770   *   'errors' property contains the array of errors, keyed by field name,
 771   *   language and delta.
 772   */
 773  function field_attach_validate($entity_type, $entity) {
 774    $errors = array();
 775    // Check generic, field-type-agnostic errors first.
 776    _field_invoke_default('validate', $entity_type, $entity, $errors);
 777    // Check field-type specific errors.
 778    _field_invoke('validate', $entity_type, $entity, $errors);
 779  
 780    // Let other modules validate the entity.
 781    // Avoid module_invoke_all() to let $errors be taken by reference.
 782    foreach (module_implements('field_attach_validate') as $module) {
 783      $function = $module . '_field_attach_validate';
 784      $function($entity_type, $entity, $errors);
 785    }
 786  
 787    if ($errors) {
 788      throw new FieldValidationException($errors);
 789    }
 790  }
 791  
 792  /**
 793   * Perform field validation against form-submitted field values.
 794   *
 795   * There are two levels of validation for fields in forms: widget
 796   * validation, and field validation.
 797   * - Widget validation steps are specific to a given widget's own form
 798   *   structure and UI metaphors. They are executed through FAPI's
 799   *   #element_validate property during normal form validation.
 800   * - Field validation steps are common to a given field type, independently of
 801   *   the specific widget being used in a given form. They are defined in the
 802   *   field type's implementation of hook_field_validate().
 803   *
 804   * This function performs field validation in the context of a form
 805   * submission. It converts field validation errors into form errors
 806   * on the correct form elements. Fieldable entity types should call
 807   * this function during their own form validation function.
 808   *
 809   * @param $entity_type
 810   *   The type of $entity; e.g. 'node' or 'user'.
 811   * @param $entity
 812   *   The entity being submitted. The 'bundle', 'id' and (if applicable)
 813   *   'revision' keys should be present. The actual field values will be read
 814   *   from $form_state['values'].
 815   * @param $form
 816   *   The form structure where field elements are attached to. This might be a
 817   *   full form structure, or a sub-element of a larger form.
 818   * @param $form_state
 819   *   An associative array containing the current state of the form.
 820   */
 821  function field_attach_form_validate($entity_type, $entity, $form, &$form_state) {
 822    // Extract field values from submitted values.
 823    _field_invoke_default('extract_form_values', $entity_type, $entity, $form, $form_state);
 824  
 825    // Perform field_level validation.
 826    try {
 827      field_attach_validate($entity_type, $entity);
 828    }
 829    catch (FieldValidationException $e) {
 830      // Pass field-level validation errors back to widgets for accurate error
 831      // flagging.
 832      foreach ($e->errors as $field_name => $field_errors) {
 833        foreach ($field_errors as $langcode => $errors) {
 834          $field_state = field_form_get_state($form['#parents'], $field_name, $langcode, $form_state);
 835          $field_state['errors'] = $errors;
 836          field_form_set_state($form['#parents'], $field_name, $langcode, $form_state, $field_state);
 837        }
 838      }
 839      _field_invoke_default('form_errors', $entity_type, $entity, $form, $form_state);
 840    }
 841  }
 842  
 843  /**
 844   * Perform necessary operations on field data submitted by a form.
 845   *
 846   * Currently, this accounts for drag-and-drop reordering of
 847   * field values, and filtering of empty values.
 848   *
 849   * @param $entity_type
 850   *   The type of $entity; e.g. 'node' or 'user'.
 851   * @param $entity
 852   *   The entity being submitted. The 'bundle', 'id' and (if applicable)
 853   *   'revision' keys should be present. The actual field values will be read
 854   *   from $form_state['values'].
 855   * @param $form
 856   *   The form structure where field elements are attached to. This might be a
 857   *   full form structure, or a sub-element of a larger form.
 858   * @param $form_state
 859   *   An associative array containing the current state of the form.
 860   */
 861  function field_attach_submit($entity_type, $entity, $form, &$form_state) {
 862    // Extract field values from submitted values.
 863    _field_invoke_default('extract_form_values', $entity_type, $entity, $form, $form_state);
 864  
 865    _field_invoke_default('submit', $entity_type, $entity, $form, $form_state);
 866  
 867    // Let other modules act on submitting the entity.
 868    // Avoid module_invoke_all() to let $form_state be taken by reference.
 869    foreach (module_implements('field_attach_submit') as $module) {
 870      $function = $module . '_field_attach_submit';
 871      $function($entity_type, $entity, $form, $form_state);
 872    }
 873  }
 874  
 875  /**
 876   * Perform necessary operations just before fields data get saved.
 877   *
 878   * We take no specific action here, we just give other
 879   * modules the opportunity to act.
 880   *
 881   * @param $entity_type
 882   *   The type of $entity; e.g. 'node' or 'user'.
 883   * @param $entity
 884   *   The entity with fields to process.
 885   */
 886  function field_attach_presave($entity_type, $entity) {
 887    _field_invoke('presave', $entity_type, $entity);
 888  
 889    // Let other modules act on presaving the entity.
 890    module_invoke_all('field_attach_presave', $entity_type, $entity);
 891  }
 892  
 893  /**
 894   * Save field data for a new entity.
 895   *
 896   * The passed-in entity must already contain its id and (if applicable)
 897   * revision id attributes.
 898   * Default values (if any) will be saved for fields not present in the
 899   * $entity.
 900   *
 901   * @param $entity_type
 902   *   The type of $entity; e.g. 'node' or 'user'.
 903   * @param $entity
 904   *   The entity with fields to save.
 905   * @return
 906   *   Default values (if any) will be added to the $entity parameter for fields
 907   *   it leaves unspecified.
 908   */
 909  function field_attach_insert($entity_type, $entity) {
 910    _field_invoke_default('insert', $entity_type, $entity);
 911    _field_invoke('insert', $entity_type, $entity);
 912  
 913    list($id, $vid, $bundle) = entity_extract_ids($entity_type, $entity);
 914  
 915    // Let any module insert field data before the storage engine, accumulating
 916    // saved fields along the way.
 917    $skip_fields = array();
 918    foreach (module_implements('field_storage_pre_insert') as $module) {
 919      $function = $module . '_field_storage_pre_insert';
 920      $function($entity_type, $entity, $skip_fields);
 921    }
 922  
 923    // Collect the storage backends used by the remaining fields in the entities.
 924    $storages = array();
 925    foreach (field_info_instances($entity_type, $bundle) as $instance) {
 926      $field = field_info_field_by_id($instance['field_id']);
 927      $field_id = $field['id'];
 928      $field_name = $field['field_name'];
 929      if (!empty($entity->$field_name)) {
 930        // Collect the storage backend if the field has not been written yet.
 931        if (!isset($skip_fields[$field_id])) {
 932          $storages[$field['storage']['type']][$field_id] = $field_id;
 933        }
 934      }
 935    }
 936  
 937    // Field storage backends save any remaining unsaved fields.
 938    foreach ($storages as $storage => $fields) {
 939      $storage_info = field_info_storage_types($storage);
 940      module_invoke($storage_info['module'], 'field_storage_write', $entity_type, $entity, FIELD_STORAGE_INSERT, $fields);
 941    }
 942  
 943    // Let other modules act on inserting the entity.
 944    module_invoke_all('field_attach_insert', $entity_type, $entity);
 945  
 946    $entity_info = entity_get_info($entity_type);
 947  }
 948  
 949  /**
 950   * Save field data for an existing entity.
 951   *
 952   * @param $entity_type
 953   *   The type of $entity; e.g. 'node' or 'user'.
 954   * @param $entity
 955   *   The entity with fields to save.
 956   */
 957  function field_attach_update($entity_type, $entity) {
 958    _field_invoke('update', $entity_type, $entity);
 959  
 960    list($id, $vid, $bundle) = entity_extract_ids($entity_type, $entity);
 961  
 962    // Let any module update field data before the storage engine, accumulating
 963    // saved fields along the way.
 964    $skip_fields = array();
 965    foreach (module_implements('field_storage_pre_update') as $module) {
 966      $function = $module . '_field_storage_pre_update';
 967      $function($entity_type, $entity, $skip_fields);
 968    }
 969  
 970    // Collect the storage backends used by the remaining fields in the entities.
 971    $storages = array();
 972    foreach (field_info_instances($entity_type, $bundle) as $instance) {
 973      $field = field_info_field_by_id($instance['field_id']);
 974      $field_id = $field['id'];
 975      $field_name = $field['field_name'];
 976      // Leave the field untouched if $entity comes with no $field_name property,
 977      // but empty the field if it comes as a NULL value or an empty array.
 978      // Function property_exists() is slower, so we catch the more frequent
 979      // cases where it's an empty array with the faster isset().
 980      if (isset($entity->$field_name) || property_exists($entity, $field_name)) {
 981        // Collect the storage backend if the field has not been written yet.
 982        if (!isset($skip_fields[$field_id])) {
 983          $storages[$field['storage']['type']][$field_id] = $field_id;
 984        }
 985      }
 986    }
 987  
 988    // Field storage backends save any remaining unsaved fields.
 989    foreach ($storages as $storage => $fields) {
 990      $storage_info = field_info_storage_types($storage);
 991      module_invoke($storage_info['module'], 'field_storage_write', $entity_type, $entity, FIELD_STORAGE_UPDATE, $fields);
 992    }
 993  
 994    // Let other modules act on updating the entity.
 995    module_invoke_all('field_attach_update', $entity_type, $entity);
 996  
 997    $entity_info = entity_get_info($entity_type);
 998    if ($entity_info['field cache']) {
 999      cache_clear_all("field:$entity_type:$id", 'cache_field');
1000    }
1001  }
1002  
1003  /**
1004   * Delete field data for an existing entity. This deletes all
1005   * revisions of field data for the entity.
1006   *
1007   * @param $entity_type
1008   *   The type of $entity; e.g. 'node' or 'user'.
1009   * @param $entity
1010   *   The entity whose field data to delete.
1011   */
1012  function field_attach_delete($entity_type, $entity) {
1013    _field_invoke('delete', $entity_type, $entity);
1014  
1015    list($id, $vid, $bundle) = entity_extract_ids($entity_type, $entity);
1016  
1017    // Collect the storage backends used by the fields in the entities.
1018    $storages = array();
1019    foreach (field_info_instances($entity_type, $bundle) as $instance) {
1020      $field = field_info_field_by_id($instance['field_id']);
1021      $field_id = $field['id'];
1022      $storages[$field['storage']['type']][$field_id] = $field_id;
1023    }
1024  
1025    // Field storage backends delete their data.
1026    foreach ($storages as $storage => $fields) {
1027      $storage_info = field_info_storage_types($storage);
1028      module_invoke($storage_info['module'], 'field_storage_delete', $entity_type, $entity, $fields);
1029    }
1030  
1031    // Let other modules act on deleting the entity.
1032    module_invoke_all('field_attach_delete', $entity_type, $entity);
1033  
1034    $entity_info = entity_get_info($entity_type);
1035    if ($entity_info['field cache']) {
1036      cache_clear_all("field:$entity_type:$id", 'cache_field');
1037    }
1038  }
1039  
1040  /**
1041   * Delete field data for a single revision of an existing entity. The
1042   * passed entity must have a revision id attribute.
1043   *
1044   * @param $entity_type
1045   *   The type of $entity; e.g. 'node' or 'user'.
1046   * @param $entity
1047   *   The entity with fields to save.
1048   */
1049  function field_attach_delete_revision($entity_type, $entity) {
1050    _field_invoke('delete_revision', $entity_type, $entity);
1051  
1052    list($id, $vid, $bundle) = entity_extract_ids($entity_type, $entity);
1053  
1054    // Collect the storage backends used by the fields in the entities.
1055    $storages = array();
1056    foreach (field_info_instances($entity_type, $bundle) as $instance) {
1057      $field = field_info_field_by_id($instance['field_id']);
1058      $field_id = $field['id'];
1059      $storages[$field['storage']['type']][$field_id] = $field_id;
1060    }
1061  
1062    // Field storage backends delete their data.
1063    foreach ($storages as $storage => $fields) {
1064      $storage_info = field_info_storage_types($storage);
1065      module_invoke($storage_info['module'], 'field_storage_delete_revision', $entity_type, $entity, $fields);
1066    }
1067  
1068    // Let other modules act on deleting the revision.
1069    module_invoke_all('field_attach_delete_revision', $entity_type, $entity);
1070  }
1071  
1072  /**
1073   * Prepare field data prior to display.
1074   *
1075   * This function lets field types and formatters load additional data
1076   * needed for display that is not automatically loaded during
1077   * field_attach_load(). It accepts an array of entities to allow query
1078   * optimisation when displaying lists of entities.
1079   *
1080   * field_attach_prepare_view() and field_attach_view() are two halves
1081   * of the same operation. It is safe to call
1082   * field_attach_prepare_view() multiple times on the same entity
1083   * before calling field_attach_view() on it, but calling any Field
1084   * API operation on an entity between passing that entity to these two
1085   * functions may yield incorrect results.
1086   *
1087   * @param $entity_type
1088   *   The type of $entities; e.g. 'node' or 'user'.
1089   * @param $entities
1090   *   An array of entities, keyed by entity id.
1091   * @param $view_mode
1092   *   View mode, e.g. 'full', 'teaser'...
1093   * @param $langcode
1094   *   (Optional) The language the field values are to be shown in. If no language
1095   *   is provided the current language is used.
1096   */
1097  function field_attach_prepare_view($entity_type, $entities, $view_mode, $langcode = NULL) {
1098    $options = array('language' => array());
1099  
1100    // To ensure hooks are only run once per entity, only process items without
1101    // the _field_view_prepared flag.
1102    // @todo: resolve this more generally for both entity and field level hooks.
1103    $prepare = array();
1104    foreach ($entities as $id => $entity) {
1105      if (empty($entity->_field_view_prepared)) {
1106        // Add this entity to the items to be prepared.
1107        $prepare[$id] = $entity;
1108  
1109        // Determine the actual language to display for each field, given the
1110        // languages available in the field data.
1111        $options['language'][$id] = field_language($entity_type, $entity, NULL, $langcode);
1112  
1113        // Mark this item as prepared.
1114        $entity->_field_view_prepared = TRUE;
1115      }
1116    }
1117  
1118    $null = NULL;
1119    // First let the field types do their preparation.
1120    _field_invoke_multiple('prepare_view', $entity_type, $prepare, $null, $null, $options);
1121    // Then let the formatters do their own specific massaging.
1122    // field_default_prepare_view() takes care of dispatching to the correct
1123    // formatters according to the display settings for the view mode.
1124    _field_invoke_multiple_default('prepare_view', $entity_type, $prepare, $view_mode, $null, $options);
1125  }
1126  
1127  /**
1128   * Returns a renderable array for the fields on an entity.
1129   *
1130   * Each field is displayed according to the display options specified in the
1131   * $instance definition for the given $view_mode.
1132   *
1133   * field_attach_prepare_view() and field_attach_view() are two halves
1134   * of the same operation. It is safe to call
1135   * field_attach_prepare_view() multiple times on the same entity
1136   * before calling field_attach_view() on it, but calling any Field
1137   * API operation on an entity between passing that entity to these two
1138   * functions may yield incorrect results.
1139   *
1140   * Sample structure:
1141   * @code
1142   * array(
1143   *   'field_foo' => array(
1144   *     '#theme' => 'field',
1145   *     '#title' => the label of the field instance,
1146   *     '#label_display' => the label display mode,
1147   *     '#object' => the fieldable entity being displayed,
1148   *     '#entity_type' => the type of the entity being displayed,
1149   *     '#language' => the language of the field values being displayed,
1150   *     '#view_mode' => the view mode,
1151   *     '#field_name' => the name of the field,
1152   *     '#field_type' => the type of the field,
1153   *     '#formatter' => the name of the formatter,
1154   *     '#items' => the field values being displayed,
1155   *     // The element's children are the formatted values returned by
1156   *     // hook_field_formatter_view().
1157   *   ),
1158   * );
1159   * @endcode
1160   *
1161   * @param $entity_type
1162   *   The type of $entity; e.g. 'node' or 'user'.
1163   * @param $entity
1164   *   The entity with fields to render.
1165   * @param $view_mode
1166   *   View mode, e.g. 'full', 'teaser'...
1167   * @param $langcode
1168   *   The language the field values are to be shown in. If no language is
1169   *   provided the current language is used.
1170   * @return
1171   *   A renderable array for the field values.
1172   */
1173  function field_attach_view($entity_type, $entity, $view_mode, $langcode = NULL) {
1174    // Determine the actual language to display for each field, given the
1175    // languages available in the field data.
1176    $display_language = field_language($entity_type, $entity, NULL, $langcode);
1177    $options = array('language' => $display_language);
1178  
1179    // Invoke field_default_view().
1180    $null = NULL;
1181    $output = _field_invoke_default('view', $entity_type, $entity, $view_mode, $null, $options);
1182  
1183    // Add custom weight handling.
1184    list($id, $vid, $bundle) = entity_extract_ids($entity_type, $entity);
1185    $output['#pre_render'][] = '_field_extra_fields_pre_render';
1186    $output['#entity_type'] = $entity_type;
1187    $output['#bundle'] = $bundle;
1188  
1189    // Let other modules alter the renderable array.
1190    $context = array(
1191      'entity_type' => $entity_type,
1192      'entity' => $entity,
1193      'view_mode' => $view_mode,
1194      'display' => $view_mode,
1195      'language' => $langcode,
1196    );
1197    drupal_alter('field_attach_view', $output, $context);
1198  
1199    // Reset the _field_view_prepared flag set in field_attach_prepare_view(),
1200    // in case the same entity is displayed with different settings later in
1201    // the request.
1202    unset($entity->_field_view_prepared);
1203  
1204    return $output;
1205  }
1206  
1207  /**
1208   * Populate the template variables with the field values available for rendering.
1209   *
1210   * The $variables array will be populated with all the field instance values
1211   * associated with the given entity type, keyed by field name; in case of
1212   * translatable fields the language currently chosen for display will be
1213   * selected.
1214   *
1215   * @param $entity_type
1216   *   The type of $entity; e.g. 'node' or 'user'.
1217   * @param $entity
1218   *   The entity with fields to render.
1219   * @param $element
1220   *   The structured array containing the values ready for rendering.
1221   * @param $variables
1222   *   The variables array is passed by reference and will be populated with field
1223   *   values.
1224   */
1225  function field_attach_preprocess($entity_type, $entity, $element, &$variables) {
1226    list(, , $bundle) = entity_extract_ids($entity_type, $entity);
1227  
1228    foreach (field_info_instances($entity_type, $bundle) as $instance) {
1229      $field_name = $instance['field_name'];
1230      if (isset($element[$field_name]['#language'])) {
1231        $langcode = $element[$field_name]['#language'];
1232        $variables[$field_name] = isset($entity->{$field_name}[$langcode]) ? $entity->{$field_name}[$langcode] : NULL;
1233      }
1234    }
1235  
1236    // Let other modules make changes to the $variables array.
1237    $context = array(
1238      'entity_type' => $entity_type,
1239      'entity' => $entity,
1240      'element' => $element,
1241    );
1242    drupal_alter('field_attach_preprocess', $variables, $context);
1243  }
1244  
1245  /**
1246   * Prepares an entity for translation.
1247   *
1248   * This function is used to fill-in the form default values for Field API fields
1249   * while performing entity translation. By default it copies all the source
1250   * values in the given source language to the new entity and assigns them the
1251   * target language.
1252   *
1253   * This is used as part of the 'per entity' translation pattern, which is
1254   * implemented only for nodes by translation.module. Other entity types may be
1255   * supported through contributed modules.
1256   *
1257   * @param $entity_type
1258   *   The type of $entity; e.g. 'node' or 'user'.
1259   * @param $entity
1260   *   The entity to be prepared for translation.
1261   * @param $langcode
1262   *   The language the entity has to be translated in.
1263   * @param $source_entity
1264   *   The source entity holding the field values to be translated.
1265   * @param $source_langcode
1266   *   The source language from which translate.
1267   */
1268  function field_attach_prepare_translation($entity_type, $entity, $langcode, $source_entity, $source_langcode) {
1269    $options = array('language' => $langcode);
1270    // Copy source field values into the entity to be prepared.
1271    _field_invoke_default('prepare_translation', $entity_type, $entity, $source_entity, $source_langcode, $options);
1272    // Let field types handle their own advanced translation pattern if needed.
1273    _field_invoke('prepare_translation', $entity_type, $entity, $source_entity, $source_langcode, $options);
1274    // Let other modules alter the entity translation.
1275    $context = array(
1276      'entity_type' => $entity_type,
1277      'langcode' => $langcode,
1278      'source_entity' => $source_entity,
1279      'source_langcode' => $source_langcode,
1280    );
1281    drupal_alter('field_attach_prepare_translation', $entity, $context);
1282  }
1283  
1284  /**
1285   * Notify field.module that a new bundle was created.
1286   *
1287   * The default SQL-based storage doesn't need to do anything about it, but
1288   * others might.
1289   *
1290   * @param $entity_type
1291   *   The entity type to which the bundle is bound.
1292   * @param $bundle
1293   *   The name of the newly created bundle.
1294   */
1295  function field_attach_create_bundle($entity_type, $bundle) {
1296    // Clear the cache.
1297    field_cache_clear();
1298  
1299    // Let other modules act on creating the bundle.
1300    module_invoke_all('field_attach_create_bundle', $entity_type, $bundle);
1301  }
1302  
1303  /**
1304   * Notify field.module that a bundle was renamed.
1305   *
1306   * @param $entity_type
1307   *   The entity type to which the bundle is bound.
1308   * @param $bundle_old
1309   *   The previous name of the bundle.
1310   * @param $bundle_new
1311   *   The new name of the bundle.
1312   */
1313  function field_attach_rename_bundle($entity_type, $bundle_old, $bundle_new) {
1314    db_update('field_config_instance')
1315      ->fields(array('bundle' => $bundle_new))
1316      ->condition('entity_type', $entity_type)
1317      ->condition('bundle', $bundle_old)
1318      ->execute();
1319  
1320    // Clear the cache.
1321    field_cache_clear();
1322  
1323    // Update bundle settings.
1324    $settings = variable_get('field_bundle_settings_' . $entity_type . '__' . $bundle_old, array());
1325    variable_set('field_bundle_settings_' . $entity_type . '__' . $bundle_new, $settings);
1326    variable_del('field_bundle_settings_' . $entity_type . '__' . $bundle_old);
1327  
1328    // Let other modules act on renaming the bundle.
1329    module_invoke_all('field_attach_rename_bundle', $entity_type, $bundle_old, $bundle_new);
1330  }
1331  
1332  /**
1333   * Notify field.module the a bundle was deleted.
1334   *
1335   * This deletes the data for the field instances as well as the field instances
1336   * themselves. This function actually just marks the data and field instances
1337   * and deleted, leaving the garbage collection for a separate process, because
1338   * it is not always possible to delete this much data in a single page request
1339   * (particularly since for some field types, the deletion is more than just a
1340   * simple DELETE query).
1341   *
1342   * @param $entity_type
1343   *   The entity type to which the bundle is bound.
1344   * @param $bundle
1345   *   The bundle to delete.
1346   */
1347  function field_attach_delete_bundle($entity_type, $bundle) {
1348    // First, delete the instances themselves. field_read_instances() must be
1349    // used here since field_info_instances() does not return instances for
1350    // disabled entity types or bundles.
1351    $instances = field_read_instances(array('entity_type' => $entity_type, 'bundle' => $bundle), array('include_inactive' => 1));
1352    foreach ($instances as $instance) {
1353      field_delete_instance($instance);
1354    }
1355  
1356    // Clear the cache.
1357    field_cache_clear();
1358  
1359    // Clear bundle display settings.
1360    variable_del('field_bundle_settings_' . $entity_type . '__' . $bundle);
1361  
1362    // Let other modules act on deleting the bundle.
1363    module_invoke_all('field_attach_delete_bundle', $entity_type, $bundle, $instances);
1364  }
1365  
1366  
1367  /**
1368   * @} End of "defgroup field_attach".
1369   */

title

Description

title

Description

title

Description

title

title

Body