1 <?php

     2 /**

     3  * @file

     4  * Attach custom data fields to Drupal entities.

     5  */

     6 

     7 /**

     8  * Base class for all exceptions thrown by Field API functions.

     9  *

    10  * This class has no functionality of its own other than allowing all

    11  * Field API exceptions to be caught by a single catch block.

    12  */

    13 class FieldException extends Exception {}

    14 

    15 /*

    16  * Load all public Field API functions. Drupal currently has no

    17  * mechanism for auto-loading core APIs, so we have to load them on

    18  * every page request.

    19  */

    20 require_once DRUPAL_ROOT . '/modules/field/field.crud.inc';

    21 require_once DRUPAL_ROOT . '/modules/field/field.default.inc';

    22 require_once DRUPAL_ROOT . '/modules/field/field.info.inc';

    23 require_once DRUPAL_ROOT . '/modules/field/field.multilingual.inc';

    24 require_once DRUPAL_ROOT . '/modules/field/field.attach.inc';

    25 require_once DRUPAL_ROOT . '/modules/field/field.form.inc';

    26 

    27 /**

    28  * @defgroup field Field API

    29  * @{

    30  * Attach custom data fields to Drupal entities.

    31  *

    32  * The Field API allows custom data fields to be attached to Drupal

    33  * entities and takes care of storing, loading, editing, and rendering

    34  * field data. Any entity type (node, user, etc.) can use the Field

    35  * API to make itself "fieldable" and thus allow fields to be attached

    36  * to it. Other modules can provide a user interface for managing custom

    37  * fields via a web browser as well as a wide and flexible variety of

    38  * data type, form element, and display format capabilities.

    39  *

    40  * The Field API defines two primary data structures, Field and

    41  * Instance, and the concept of a Bundle. A Field defines a

    42  * particular type of data that can be attached to entities. A Field

    43  * Instance is a Field attached to a single Bundle. A Bundle is a set

    44  * of fields that are treated as a group by the Field Attach API and

    45  * is related to a single fieldable entity type.

    46  *

    47  * For example, suppose a site administrator wants Article nodes to

    48  * have a subtitle and photo. Using the Field API or Field UI module,

    49  * the administrator creates a field named 'subtitle' of type 'text'

    50  * and a field named 'photo' of type 'image'. The administrator

    51  * (again, via a UI) creates two Field Instances, one attaching the

    52  * field 'subtitle' to the 'node' bundle 'article' and one attaching

    53  * the field 'photo' to the 'node' bundle 'article'. When the node

    54  * system uses the Field Attach API to load all fields for an Article

    55  * node, it passes the node's entity type (which is 'node') and

    56  * content type (which is 'article') as the node's bundle.

    57  * field_attach_load() then loads the 'subtitle' and 'photo' fields

    58  * because they are both attached to the 'node' bundle 'article'.

    59  *

    60  * Field definitions are represented as an array of key/value pairs.

    61  *

    62  * array $field:

    63  * - id (integer, read-only): The primary identifier of the field. It is

    64  *   assigned automatically by field_create_field().

    65  * - field_name (string): The name of the field. Each field name is unique

    66  *   within Field API. When a field is attached to an entity, the field's data

    67  *   is stored in $entity->$field_name. Maximum length is 32 characters.

    68  * - type (string): The type of the field, such as 'text' or 'image'. Field

    69  *   types are defined by modules that implement hook_field_info().

    70  * - entity_types (array): The array of entity types that can hold instances

    71  *   of this field. If empty or not specified, the field can have instances

    72  *   in any entity type.

    73  * - cardinality (integer): The number of values the field can hold. Legal

    74  *   values are any positive integer or FIELD_CARDINALITY_UNLIMITED.

    75  * - translatable (integer): Whether the field is translatable.

    76  * - locked (integer): Whether or not the field is available for editing. If

    77  *   TRUE, users can't change field settings or create new instances of the

    78  *   field in the UI. Defaults to FALSE.

    79  * - module (string, read-only): The name of the module that implements the

    80  *   field type.

    81  * - active (integer, read-only): TRUE if the module that implements the field

    82  *   type is currently enabled, FALSE otherwise.

    83  * - deleted (integer, read-only): TRUE if this field has been deleted, FALSE

    84  *   otherwise. Deleted fields are ignored by the Field Attach API. This

    85  *   property exists because fields can be marked for deletion but only

    86  *   actually destroyed by a separate garbage-collection process.

    87  * - columns (array, read-only): An array of the Field API columns used to

    88  *   store each value of this field. The column list may depend on field

    89  *   settings; it is not constant per field type. Field API column

    90  *   specifications are exactly like Schema API column specifications but,

    91  *   depending on the field storage module in use, the name of the column may

    92  *   not represent an actual column in an SQL database.

    93  * - indexes (array): An array of indexes on data columns, using the same

    94  *   definition format as Schema API index specifications. Only columns that

    95  *   appear in the 'columns' setting are allowed. Note that field types can

    96  *   specify default indexes, which can be modified or added to when

    97  *   creating a field.

    98  * - foreign keys: (optional) An associative array of relations, using the same

    99  *   structure as the 'foreign keys' definition of hook_schema(). Note,

   100  *   however, that the field data is not necessarily stored in SQL. Also, the

   101  *   possible usage is limited, as you cannot specify another field as

   102  *   related, only existing SQL tables, such as filter formats.

   103  * - settings (array): A sub-array of key/value pairs of field-type-specific

   104  *   settings. Each field type module defines and documents its own field

   105  *   settings.

   106  * - storage (array): A sub-array of key/value pairs identifying the storage

   107  *   backend to use for the for the field:

   108  *   - type (string): The storage backend used by the field. Storage backends

   109  *     are defined by modules that implement hook_field_storage_info().

   110  *   - module (string, read-only): The name of the module that implements the

   111  *     storage backend.

   112  *   - active (integer, read-only): TRUE if the module that implements the

   113  *     storage backend is currently enabled, FALSE otherwise.

   114  *   - settings (array): A sub-array of key/value pairs of settings. Each

   115  *     storage backend defines and documents its own settings.

   116  *

   117  * Field instance definitions are represented as an array of key/value pairs.

   118  *

   119  * array $instance:

   120  * - id (integer, read-only): The primary identifier of this field instance.

   121  *   It is assigned automatically by field_create_instance().

   122  * - field_id (integer, read-only): The foreign key of the field attached to

   123  *   the bundle by this instance. It is populated automatically by

   124  *   field_create_instance().

   125  * - field_name (string): The name of the field attached to the bundle by this

   126  *   instance.

   127  * - entity_type (string): The name of the entity type the instance is attached

   128  *   to.

   129  * - bundle (string): The name of the bundle that the field is attached to.

   130  * - label (string): A human-readable label for the field when used with this

   131  *   bundle. For example, the label will be the title of Form API elements

   132  *   for this instance.

   133  * - description (string): A human-readable description for the field when

   134  *   used with this bundle. For example, the description will be the help

   135  *   text of Form API elements for this instance.

   136  * - required (integer): TRUE if a value for this field is required when used

   137  *   with this bundle, FALSE otherwise. Currently, required-ness is only

   138  *   enforced during Form API operations, not by field_attach_load(),

   139  *   field_attach_insert(), or field_attach_update().

   140  * - default_value_function (string): The name of the function, if any, that

   141  *   will provide a default value.

   142  * - default_value (array): If default_value_function is not set, then fixed

   143  *   values can be provided.

   144  * - deleted (integer, read-only): TRUE if this instance has been deleted,

   145  *   FALSE otherwise. Deleted instances are ignored by the Field Attach API.

   146  *   This property exists because instances can be marked for deletion but

   147  *   only actually destroyed by a separate garbage-collection process.

   148  * - settings (array): A sub-array of key/value pairs of field-type-specific

   149  *   instance settings. Each field type module defines and documents its own

   150  *   instance settings.

   151  * - widget (array): A sub-array of key/value pairs identifying the Form API

   152  *   input widget for the field when used by this bundle:

   153  *   - type (string): The type of the widget, such as text_textfield. Widget

   154  *     types are defined by modules that implement hook_field_widget_info().

   155  *   - settings (array): A sub-array of key/value pairs of

   156  *     widget-type-specific settings. Each field widget type module defines

   157  *     and documents its own widget settings.

   158  *   - weight (float): The weight of the widget relative to the other elements

   159  *     in entity edit forms.

   160  *   - module (string, read-only): The name of the module that implements the

   161  *     widget type.

   162  * - display (array): A sub-array of key/value pairs identifying the way field

   163  *   values should be displayed in each of the entity type's view modes, plus

   164  *   the 'default' mode. For each view mode, Field UI lets site administrators

   165  *   define whether they want to use a dedicated set of display options or the

   166  *   'default' options to reduce the number of displays to maintain as they

   167  *   add new fields. For nodes, on a fresh install, only the 'teaser' view

   168  *   mode is configured to use custom display options, all other view modes

   169  *   defined use the 'default' options by default. When programmatically

   170  *   adding field instances on nodes, it is therefore recommended to at least

   171  *   specify display options for 'default' and 'teaser':

   172  *   - default (array): A sub-array of key/value pairs describing the display

   173  *     options to be used when the field is being displayed in view modes

   174  *     that are not configured to use dedicated display options:

   175  *     - label (string): Position of the label. 'inline', 'above' and

   176  *       'hidden' are the values recognized by the default 'field' theme

   177  *       implementation.

   178  *     - type (string): The type of the display formatter, or 'hidden' for

   179  *       no display.

   180  *     - settings (array): A sub-array of key/value pairs of display

   181  *       options specific to the formatter.

   182  *     - weight (float): The weight of the field relative to the other entity

   183  *       components displayed in this view mode.

   184  *     - module (string, read-only): The name of the module which implements

   185  *       the display formatter.

   186  *   - some_mode: A sub-array of key/value pairs describing the display

   187  *     options to be used when the field is being displayed in the 'some_mode'

   188  *     view mode. Those options will only be actually applied at run time if

   189  *     the view mode is not configured to use default settings for this bundle:

   190  *     - ...

   191  *   - other_mode:

   192  *     - ...

   193  *

   194  * The (default) render arrays produced for field instances are documented at

   195  * field_attach_view().

   196  *

   197  * Bundles are represented by two strings, an entity type and a bundle name.

   198  *

   199  * - @link field_types Field Types API @endlink. Defines field types,

   200  *   widget types, and display formatters. Field modules use this API

   201  *   to provide field types like Text and Node Reference along with the

   202  *   associated form elements and display formatters.

   203  *

   204  * - @link field_crud Field CRUD API @endlink. Create, updates, and

   205  *   deletes fields, bundles (a.k.a. "content types"), and instances.

   206  *   Modules use this API, often in hook_install(), to create

   207  *   custom data structures.

   208  *

   209  * - @link field_attach Field Attach API @endlink. Connects entity

   210  *   types to the Field API. Field Attach API functions load, store,

   211  *   generate Form API structures, display, and perform a variety of

   212  *   other functions for field data connected to individual entities.

   213  *   Fieldable entity types like node and user use this API to make

   214  *   themselves fieldable.

   215  *

   216  * - @link field_info Field Info API @endlink. Exposes information

   217  *   about all fields, instances, widgets, and related information

   218  *   defined by or with the Field API.

   219  *

   220  * - @link field_storage Field Storage API @endlink. Provides a

   221  *   pluggable back-end storage system for actual field data. The

   222  *   default implementation, field_sql_storage.module, stores field data

   223  *   in the local SQL database.

   224  *

   225  * - @link field_purge Field API bulk data deletion @endlink. Cleans

   226  *   up after bulk deletion operations such as field_delete_field()

   227  *   and field_delete_instance().

   228  *

   229  * - @link field_language Field language API @endlink. Provides native

   230  *   multilingual support for the Field API.

   231  */

   232 

   233 /**

   234  * Value for field API indicating a field accepts an unlimited number of values.

   235  */

   236 define('FIELD_CARDINALITY_UNLIMITED', -1);

   237 

   238 /**

   239  * Value for field API indicating a widget doesn't accept default values.

   240  *

   241  * @see hook_field_widget_info()

   242  */

   243 define('FIELD_BEHAVIOR_NONE', 0x0001);

   244 

   245 /**

   246  * Value for field API concerning widget default and multiple value settings.

   247  *

   248  * @see hook_field_widget_info()

   249  *

   250  * When used in a widget default context, indicates the widget accepts default

   251  * values. When used in a multiple value context for a widget that allows the

   252  * input of one single field value, indicates that the widget will be repeated

   253  * for each value input.

   254  */

   255 define('FIELD_BEHAVIOR_DEFAULT', 0x0002);

   256 

   257 /**

   258  * Value for field API indicating a widget can receive several field values.

   259  *

   260  * @see hook_field_widget_info()

   261  */

   262 define('FIELD_BEHAVIOR_CUSTOM', 0x0004);

   263 

   264 /**

   265  * Age argument for loading the most recent version of an entity's

   266  * field data with field_attach_load().

   267  */

   268 define('FIELD_LOAD_CURRENT', 'FIELD_LOAD_CURRENT');

   269 

   270 /**

   271  * Age argument for loading the version of an entity's field data

   272  * specified in the entity with field_attach_load().

   273  */

   274 define('FIELD_LOAD_REVISION', 'FIELD_LOAD_REVISION');

   275 

   276 /**

   277  * Exception class thrown by hook_field_update_forbid().

   278  */

   279 class FieldUpdateForbiddenException extends FieldException {}

   280 

   281 /**

   282  * Implements hook_help().

   283  */

   284 function field_help($path, $arg) {

   285   switch ($path) {

   286     case 'admin/help#field':

   287       $output = '';

   288       $output .= '<h3>' . t('About') . '</h3>';

   289       $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>';

   290       $output .= '<h3>' . t('Uses') . '</h3>';

   291       $output .= '<dl>';

   292       $output .= '<dt>' . t('Enabling field types') . '</dt>';

   293       $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')));

   294 

   295       // Make a list of all widget and field modules currently enabled, in

   296       // order by displayed module name (module names are not translated).

   297       $items = array();

   298       $info = system_get_info('module');

   299       $modules = array_merge(module_implements('field_info'), module_implements('field_widget_info'));

   300       $modules = array_unique($modules);

   301       sort($modules);

   302       foreach ($modules as $module) {

   303         $display = $info[$module]['name'];

   304         if (module_hook($module, 'help')) {

   305           $items['items'][] = l($display, 'admin/help/' . $module);

   306         }

   307         else {

   308           $items['items'][] = $display;

   309         }

   310       }

   311       $output .= theme('item_list', $items) . '</dd>';

   312       $output .= '<dt>' . t('Managing field data storage') . '</dt>';

   313       $output .= '<dd>' . t('Developers of field modules can either use the default <a href="@sql-store">Field SQL storage module</a> to store data for their fields, or a contributed or custom module developed using the <a href="@storage-api">field storage API</a>.', array('@storage-api' => 'http://api.drupal.org/api/group/field_storage/7', '@sql-store' => url('admin/help/field_sql_storage'))) . '</dd>';

   314       $output .= '</dl>';

   315       return $output;

   316   }

   317 }

   318 

   319 /**

   320  * Implements hook_permission().

   321  */

   322 function field_permission() {

   323   return array(

   324     'administer fields' => array(

   325       'title' => t('Administer fields'),

   326       'description' => t('Additional permissions are required based on what the fields are attached to (for example, <a href="@url">administer content types</a> to manage fields attached to content).', array(

   327         '@url' => '#module-node',

   328       )),

   329       'restrict access' => TRUE,

   330     ),

   331   );

   332 }

   333 

   334 /**

   335  * Implements hook_theme().

   336  */

   337 function field_theme() {

   338   return array(

   339     'field' => array(

   340       'render element' => 'element',

   341     ),

   342     'field_multiple_value_form' => array(

   343       'render element' => 'element',

   344     ),

   345   );

   346 }

   347 

   348 /**

   349  * Implements hook_cron().

   350  */

   351 function field_cron() {

   352   // Refresh the 'active' status of fields.

   353   field_sync_field_status();

   354 

   355   // Do a pass of purging on deleted Field API data, if any exists.

   356   $limit = variable_get('field_purge_batch_size', 10);

   357   field_purge_batch($limit);

   358 }

   359 

   360 /**

   361  * Implements hook_system_info_alter().

   362  *

   363  * Goes through a list of all modules that provide a field type, and makes them

   364  * required if there are any active fields of that type.

   365  */

   366 function field_system_info_alter(&$info, $file, $type) {

   367   if ($type == 'module' && module_hook($file->name, 'field_info')) {

   368     $fields = field_read_fields(array('module' => $file->name), array('include_deleted' => TRUE));

   369     if ($fields) {

   370       $info['required'] = TRUE;

   371 

   372       // Provide an explanation message (only mention pending deletions if there

   373       // remains no actual, non-deleted fields)

   374       $non_deleted = FALSE;

   375       foreach ($fields as $field) {

   376         if (empty($field['deleted'])) {

   377           $non_deleted = TRUE;

   378           break;

   379         }

   380       }

   381       if ($non_deleted) {

   382         if (module_exists('field_ui')) {

   383           $explanation = t('Field type(s) in use - see <a href="@fields-page">Field list</a>', array('@fields-page' => url('admin/reports/fields')));

   384         }

   385         else {

   386           $explanation = t('Fields type(s) in use');

   387         }

   388       }

   389       else {

   390         $explanation = t('Fields pending deletion');

   391       }

   392       $info['explanation'] = $explanation;

   393     }

   394   }

   395 }

   396 

   397 /**

   398  * Implements hook_flush_caches().

   399  */

   400 function field_flush_caches() {

   401   // Refresh the 'active' status of fields.

   402   field_sync_field_status();

   403 

   404   // Request a flush of our cache table.

   405   return array('cache_field');

   406 }

   407 

   408 /**

   409  * Implements hook_modules_enabled().

   410  */

   411 function field_modules_enabled($modules) {

   412   // Refresh the 'active' status of fields.

   413   field_sync_field_status();

   414 }

   415 

   416 /**

   417  * Implements hook_modules_disabled().

   418  */

   419 function field_modules_disabled($modules) {

   420   // Refresh the 'active' status of fields.

   421   field_sync_field_status();

   422 }

   423 

   424 /**

   425  * Refreshes the 'active' and 'storage_active' columns for fields.

   426  */

   427 function field_sync_field_status() {

   428   // Refresh the 'active' and 'storage_active' columns according to the current

   429   // set of enabled modules.

   430   $modules = module_list();

   431   foreach ($modules as $module_name) {

   432     field_associate_fields($module_name);

   433   }

   434   db_update('field_config')

   435     ->fields(array('active' => 0))

   436     ->condition('module', $modules, 'NOT IN')

   437     ->execute();

   438   db_update('field_config')

   439     ->fields(array('storage_active' => 0))

   440     ->condition('storage_module', $modules, 'NOT IN')

   441     ->execute();

   442 }

   443 

   444 /**

   445  * Allows a module to update the database for fields and columns it controls.

   446  *

   447  * @param $module

   448  *   The name of the module to update on.

   449  */

   450 function field_associate_fields($module) {

   451   // Associate field types.

   452   $field_types = (array) module_invoke($module, 'field_info');

   453   if ($field_types) {

   454     db_update('field_config')

   455       ->fields(array('module' => $module, 'active' => 1))

   456       ->condition('type', array_keys($field_types))

   457       ->execute();

   458   }

   459   // Associate storage backends.

   460   $storage_types = (array) module_invoke($module, 'field_storage_info');

   461   if ($storage_types) {

   462     db_update('field_config')

   463       ->fields(array('storage_module' => $module, 'storage_active' => 1))

   464       ->condition('storage_type', array_keys($storage_types))

   465       ->execute();

   466   }

   467 }

   468 

   469 /**

   470  * Helper function to get the default value for a field on an entity.

   471  *

   472  * @param $entity_type

   473  *   The type of $entity; e.g., 'node' or 'user'.

   474  * @param $entity

   475  *   The entity for the operation.

   476  * @param $field

   477  *   The field structure.

   478  * @param $instance

   479  *   The instance structure.

   480  * @param $langcode

   481  *   The field language to fill-in with the default value.

   482  */

   483 function field_get_default_value($entity_type, $entity, $field, $instance, $langcode = NULL) {

   484   $items = array();

   485   if (!empty($instance['default_value_function'])) {

   486     $function = $instance['default_value_function'];

   487     if (function_exists($function)) {

   488       $items = $function($entity_type, $entity, $field, $instance, $langcode);

   489     }

   490   }

   491   elseif (!empty($instance['default_value'])) {

   492     $items = $instance['default_value'];

   493   }

   494   return $items;

   495 }

   496 

   497 /**

   498  * Helper function to filter out empty field values.

   499  *

   500  * @param $field

   501  *   The field definition.

   502  * @param $items

   503  *   The field values to filter.

   504  *

   505  * @return

   506  *   The array of items without empty field values. The function also renumbers

   507  *   the array keys to ensure sequential deltas.

   508  */

   509 function _field_filter_items($field, $items) {

   510   $function = $field['module'] . '_field_is_empty';

   511   foreach ((array) $items as $delta => $item) {

   512     // Explicitly break if the function is undefined.

   513     if ($function($item, $field)) {

   514       unset($items[$delta]);

   515     }

   516   }

   517   return array_values($items);

   518 }

   519 

   520 /**

   521  * Helper function to sort items in a field according to

   522  * user drag-n-drop reordering.

   523  */

   524 function _field_sort_items($field, $items) {

   525   if (($field['cardinality'] > 1 || $field['cardinality'] == FIELD_CARDINALITY_UNLIMITED) && isset($items[0]['_weight'])) {

   526     usort($items, '_field_sort_items_helper');

   527     foreach ($items as $delta => $item) {

   528       if (is_array($items[$delta])) {

   529         unset($items[$delta]['_weight']);

   530       }

   531     }

   532   }

   533   return $items;

   534 }

   535 

   536 /**

   537  * Sort function for items order.

   538  * (copied form element_sort(), which acts on #weight keys)

   539  */

   540 function _field_sort_items_helper($a, $b) {

   541   $a_weight = (is_array($a) ? $a['_weight'] : 0);

   542   $b_weight = (is_array($b) ? $b['_weight'] : 0);

   543   return $a_weight - $b_weight;

   544 }

   545 

   546 /**

   547  * Same as above, using ['_weight']['#value']

   548  */

   549 function _field_sort_items_value_helper($a, $b) {

   550   $a_weight = (is_array($a) && isset($a['_weight']['#value']) ? $a['_weight']['#value'] : 0);

   551   $b_weight = (is_array($b) && isset($b['_weight']['#value']) ? $b['_weight']['#value'] : 0);

   552   return $a_weight - $b_weight;

   553 }

   554 

   555 /**

   556  * Gets or sets administratively defined bundle settings.

   557  *

   558  * @param string $entity_type

   559  *   The type of $entity; e.g., 'node' or 'user'.

   560  * @param string $bundle

   561  *   The bundle name.

   562  * @param array|null $settings

   563  *   (optional) The settings to store, an associative array with the following

   564  *   elements:

   565  *   - view_modes: An associative array keyed by view mode, with the following

   566  *     key/value pairs:

   567  *     - custom_settings: Boolean specifying whether the view mode uses a

   568  *       dedicated set of display options (TRUE), or the 'default' options

   569  *       (FALSE). Defaults to FALSE.

   570  *   - extra_fields: An associative array containing the form and display

   571  *     settings for extra fields (also known as pseudo-fields):

   572  *     - form: An associative array whose keys are the names of extra fields,

   573  *       and whose values are associative arrays with the following elements:

   574  *       - weight: The weight of the extra field, determining its position on an

   575  *         entity form.

   576  *     - display: An associative array whose keys are the names of extra fields,

   577  *       and whose values are associative arrays keyed by the name of view

   578  *       modes. This array must include an item for the 'default' view mode.

   579  *       Each view mode sub-array contains the following elements:

   580  *       - weight: The weight of the extra field, determining its position when

   581  *         an entity is viewed.

   582  *       - visible: TRUE if the extra field is visible, FALSE otherwise.

   583  *

   584  * @return array|null

   585  *   If no $settings are passed, the current settings are returned.

   586  */

   587 function field_bundle_settings($entity_type, $bundle, $settings = NULL) {

   588   if (isset($settings)) {

   589     variable_set('field_bundle_settings_' . $entity_type . '__' . $bundle, $settings);

   590     field_info_cache_clear();

   591   }

   592   else {

   593     $settings = variable_get('field_bundle_settings_' . $entity_type . '__' . $bundle, array());

   594     $settings += array(

   595       'view_modes' => array(),

   596       'extra_fields' => array(),

   597     );

   598     $settings['extra_fields'] += array(

   599       'form' => array(),

   600       'display' => array(),

   601     );

   602 

   603     return $settings;

   604   }

   605 }

   606 

   607 /**

   608  * Returns view mode settings in a given bundle.

   609  *

   610  * @param $entity_type

   611  *   The type of entity; e.g. 'node' or 'user'.

   612  * @param $bundle

   613  *   The bundle name to return view mode settings for.

   614  *

   615  * @return

   616  *   An array keyed by view mode, with the following key/value pairs:

   617  *   - custom_settings: Boolean specifying whether the view mode uses a

   618  *     dedicated set of display options (TRUE), or the 'default' options

   619  *     (FALSE). Defaults to FALSE.

   620  */

   621 function field_view_mode_settings($entity_type, $bundle) {

   622   $cache = &drupal_static(__FUNCTION__, array());

   623 

   624   if (!isset($cache[$entity_type][$bundle])) {

   625     $bundle_settings = field_bundle_settings($entity_type, $bundle);

   626     $settings = $bundle_settings['view_modes'];

   627     // Include view modes for which nothing has been stored yet, but whose

   628     // definition in hook_entity_info() specify they should use custom settings

   629     // by default.

   630     $entity_info = entity_get_info($entity_type);

   631     foreach ($entity_info['view modes'] as $view_mode => $view_mode_info) {

   632       if (!isset($settings[$view_mode]['custom_settings']) && $view_mode_info['custom settings']) {

   633         $settings[$view_mode]['custom_settings'] = TRUE;

   634       }

   635     }

   636     $cache[$entity_type][$bundle] = $settings;

   637   }

   638 

   639   return $cache[$entity_type][$bundle];

   640 }

   641 

   642 /**

   643  * Returns the display settings to use for an instance in a given view mode.

   644  *

   645  * @param $instance

   646  *   The field instance being displayed.

   647  * @param $view_mode

   648  *   The view mode.

   649  * @param $entity

   650  *   The entity being displayed.

   651  *

   652  * @return

   653  *   The display settings to be used when displaying the field values.

   654  */

   655 function field_get_display($instance, $view_mode, $entity) {

   656   // Check whether the view mode uses custom display settings or the 'default'

   657   // mode.

   658   $view_mode_settings = field_view_mode_settings($instance['entity_type'], $instance['bundle']);

   659   $actual_mode = (!empty($view_mode_settings[$view_mode]['custom_settings']) ? $view_mode : 'default');

   660   $display = $instance['display'][$actual_mode];

   661 

   662   // Let modules alter the display settings.

   663   $context = array(

   664     'entity_type' => $instance['entity_type'],

   665     'field' => field_info_field($instance['field_name']),

   666     'instance' => $instance,

   667     'entity' => $entity,

   668     'view_mode' => $view_mode,

   669   );

   670   drupal_alter(array('field_display', 'field_display_' . $instance['entity_type']), $display, $context);

   671 

   672   return $display;

   673 }

   674 

   675 /**

   676  * Returns the display settings to use for pseudo-fields in a given view mode.

   677  *

   678  * @param $entity_type

   679  *   The type of $entity; e.g., 'node' or 'user'.

   680  * @param $bundle

   681  *   The bundle name.

   682  * @param $view_mode

   683  *   The view mode.

   684  *

   685  * @return

   686  *   The display settings to be used when viewing the bundle's pseudo-fields.

   687  */

   688 function field_extra_fields_get_display($entity_type, $bundle, $view_mode) {

   689   // Check whether the view mode uses custom display settings or the 'default'

   690   // mode.

   691   $view_mode_settings = field_view_mode_settings($entity_type, $bundle);

   692   $actual_mode = (!empty($view_mode_settings[$view_mode]['custom_settings'])) ? $view_mode : 'default';

   693   $extra_fields = field_info_extra_fields($entity_type, $bundle, 'display');

   694 

   695   $displays = array();

   696   foreach ($extra_fields as $name => $value) {

   697     $displays[$name] = $extra_fields[$name]['display'][$actual_mode];

   698   }

   699 

   700   // Let modules alter the display settings.

   701   $context = array(

   702     'entity_type' => $entity_type,

   703     'bundle' => $bundle,

   704     'view_mode' => $view_mode,

   705   );

   706   drupal_alter('field_extra_fields_display', $displays, $context);

   707 

   708   return $displays;

   709 }

   710 

   711 /**

   712  * Pre-render callback to adjust weights and visibility of non-field elements.

   713  */

   714 function _field_extra_fields_pre_render($elements) {

   715   $entity_type = $elements['#entity_type'];

   716   $bundle = $elements['#bundle'];

   717 

   718   if (isset($elements['#type']) && $elements['#type'] == 'form') {

   719     $extra_fields = field_info_extra_fields($entity_type, $bundle, 'form');

   720     foreach ($extra_fields as $name => $settings) {

   721       if (isset($elements[$name])) {

   722         $elements[$name]['#weight'] = $settings['weight'];

   723       }

   724     }

   725   }

   726   elseif (isset($elements['#view_mode'])) {

   727     $view_mode = $elements['#view_mode'];

   728     $extra_fields = field_extra_fields_get_display($entity_type, $bundle, $view_mode);

   729     foreach ($extra_fields as $name => $settings) {

   730       if (isset($elements[$name])) {

   731         $elements[$name]['#weight'] = $settings['weight'];

   732         // Visibility: make sure we do not accidentally show a hidden element.

   733         $elements[$name]['#access'] = isset($elements[$name]['#access']) ? ($elements[$name]['#access'] && $settings['visible']) : $settings['visible'];

   734       }

   735     }

   736   }

   737 

   738   return $elements;

   739 }

   740 

   741 /**

   742  * Clear the field info and field data caches.

   743  */

   744 function field_cache_clear() {

   745   cache_clear_all('*', 'cache_field', TRUE);

   746   field_info_cache_clear();

   747 }

   748 

   749 /**

   750  * Like filter_xss_admin(), but with a shorter list of allowed tags.

   751  *

   752  * Used for items entered by administrators, like field descriptions,

   753  * allowed values, where some (mainly inline) mark-up may be desired

   754  * (so check_plain() is not acceptable).

   755  */

   756 function field_filter_xss($string) {

   757   return filter_xss($string, _field_filter_xss_allowed_tags());

   758 }

   759 

   760 /**

   761  * List of tags allowed by field_filter_xss().

   762  */

   763 function _field_filter_xss_allowed_tags() {

   764   return array('a', 'b', 'big',  'code', 'del', 'em', 'i', 'ins',  'pre', 'q', 'small', 'span', 'strong', 'sub', 'sup', 'tt', 'ol', 'ul', 'li', 'p', 'br', 'img');

   765 }

   766 

   767 /**

   768  * Human-readable list of allowed tags, for display in help texts.

   769  */

   770 function _field_filter_xss_display_allowed_tags() {

   771   return '<' . implode('> <', _field_filter_xss_allowed_tags()) . '>';

   772 }

   773 

   774 /**

   775  * Returns a renderable array for a single field value.

   776  *

   777  * @param $entity_type

   778  *   The type of $entity; e.g., 'node' or 'user'.

   779  * @param $entity

   780  *   The entity containing the field to display. Must at least contain the id

   781  *   key and the field data to display.

   782  * @param $field_name

   783  *   The name of the field to display.

   784  * @param $item

   785  *   The field value to display, as found in

   786  *   $entity->field_name[$langcode][$delta].

   787  * @param $display

   788  *   Can be either the name of a view mode, or an array of display settings.

   789  *   See field_view_field() for more information.

   790  * @param $langcode

   791  *   (Optional) The language of the value in $item. If not provided, the

   792  *   current language will be assumed.

   793  * @return

   794  *   A renderable array for the field value.

   795  */

   796 function field_view_value($entity_type, $entity, $field_name, $item, $display = array(), $langcode = NULL) {

   797   $output = array();

   798 

   799   if ($field = field_info_field($field_name)) {

   800     // Determine the langcode that will be used by language fallback.

   801     $langcode = field_language($entity_type, $entity, $field_name, $langcode);

   802 

   803     // Push the item as the single value for the field, and defer to

   804     // field_view_field() to build the render array for the whole field.

   805     $clone = clone $entity;

   806     $clone->{$field_name}[$langcode] = array($item);

   807     $elements = field_view_field($entity_type, $clone, $field_name, $display, $langcode);

   808 

   809     // Extract the part of the render array we need.

   810     $output = isset($elements[0]) ? $elements[0] : array();

   811     if (isset($elements['#access'])) {

   812       $output['#access'] = $elements['#access'];

   813     }

   814   }

   815 

   816   return $output;

   817 }

   818 

   819 /**

   820  * Returns a renderable array for the value of a single field in an entity.

   821  *

   822  * The resulting output is a fully themed field with label and multiple values.

   823  *

   824  * This function can be used by third-party modules that need to output an

   825  * isolated field.

   826  * - Do not use inside node (or any other entity) templates; use

   827  *   render($content[FIELD_NAME]) instead.

   828  * - Do not use to display all fields in an entity; use

   829  *   field_attach_prepare_view() and field_attach_view() instead.

   830  * - The field_view_value() function can be used to output a single formatted

   831  *   field value, without label or wrapping field markup.

   832  *

   833  * The function takes care of invoking the prepare_view steps. It also respects

   834  * field access permissions.

   835  *

   836  * @param $entity_type

   837  *   The type of $entity; e.g., 'node' or 'user'.

   838  * @param $entity

   839  *   The entity containing the field to display. Must at least contain the id

   840  *   key and the field data to display.

   841  * @param $field_name

   842  *   The name of the field to display.

   843  * @param $display

   844  *   Can be either:

   845  *   - The name of a view mode. The field will be displayed according to the

   846  *     display settings specified for this view mode in the $instance

   847  *     definition for the field in the entity's bundle.

   848  *     If no display settings are found for the view mode, the settings for

   849  *     the 'default' view mode will be used.

   850  *   - An array of display settings, as found in the 'display' entry of

   851  *     $instance definitions. The following key/value pairs are allowed:

   852  *     - label: (string) Position of the label. The default 'field' theme

   853  *       implementation supports the values 'inline', 'above' and 'hidden'.

   854  *       Defaults to 'above'.

   855  *     - type: (string) The formatter to use. Defaults to the

   856  *       'default_formatter' for the field type, specified in

   857  *       hook_field_info(). The default formatter will also be used if the

   858  *       requested formatter is not available.

   859  *     - settings: (array) Settings specific to the formatter. Defaults to the

   860  *       formatter's default settings, specified in

   861  *       hook_field_formatter_info().

   862  *     - weight: (float) The weight to assign to the renderable element.

   863  *       Defaults to 0.

   864  * @param $langcode

   865  *   (Optional) The language the field values are to be shown in. The site's

   866  *   current language fallback logic will be applied no values are available

   867  *   for the language. If no language is provided the current language will be

   868  *   used.

   869  * @return

   870  *   A renderable array for the field value.

   871  *

   872  * @see field_view_value()

   873  */

   874 function field_view_field($entity_type, $entity, $field_name, $display = array(), $langcode = NULL) {

   875   $output = array();

   876 

   877   if ($field = field_info_field($field_name)) {

   878     if (is_array($display)) {

   879       // When using custom display settings, fill in default values.

   880       $cache = _field_info_field_cache();

   881       $display = $cache->prepareInstanceDisplay($display, $field["type"]);

   882     }

   883 

   884     // Hook invocations are done through the _field_invoke() functions in

   885     // 'single field' mode, to reuse the language fallback logic.

   886     // Determine the actual language to display for the field, given the

   887     // languages available in the field data.

   888     $display_language = field_language($entity_type, $entity, $field_name, $langcode);

   889     $options = array('field_name' => $field_name, 'language' => $display_language);

   890     $null = NULL;

   891 

   892     // Invoke prepare_view steps if needed.

   893     if (empty($entity->_field_view_prepared)) {

   894       list($id) = entity_extract_ids($entity_type, $entity);

   895 

   896       // First let the field types do their preparation.

   897       _field_invoke_multiple('prepare_view', $entity_type, array($id => $entity), $display, $null, $options);

   898       // Then let the formatters do their own specific massaging.

   899       _field_invoke_multiple_default('prepare_view', $entity_type, array($id => $entity), $display, $null, $options);

   900     }

   901 

   902     // Build the renderable array.

   903     $result = _field_invoke_default('view', $entity_type, $entity, $display, $null, $options);

   904 

   905     // Invoke hook_field_attach_view_alter() to let other modules alter the

   906     // renderable array, as in a full field_attach_view() execution.

   907     $context = array(

   908       'entity_type' => $entity_type,

   909       'entity' => $entity,

   910       'view_mode' => '_custom',

   911       'display' => $display,

   912       'language' => $langcode,

   913     );

   914     drupal_alter('field_attach_view', $result, $context);

   915 

   916     if (isset($result[$field_name])) {

   917       $output = $result[$field_name];

   918     }

   919   }

   920 

   921   return $output;

   922 }

   923 

   924 /**

   925  * Returns the field items in the language they currently would be displayed.

   926  *

   927  * @param $entity_type

   928  *   The type of $entity; e.g., 'node' or 'user'.

   929  * @param $entity

   930  *   The entity containing the data to be displayed.

   931  * @param $field_name

   932  *   The field to be displayed.

   933  * @param $langcode

   934  *   (optional) The language code $entity->{$field_name} has to be displayed in.

   935  *   Defaults to the current language.

   936  *

   937  * @return

   938  *   An array of field items keyed by delta if available, FALSE otherwise.

   939  */

   940 function field_get_items($entity_type, $entity, $field_name, $langcode = NULL) {

   941   $langcode = field_language($entity_type, $entity, $field_name, $langcode);

   942   return isset($entity->{$field_name}[$langcode]) ? $entity->{$field_name}[$langcode] : FALSE;

   943 }

   944 

   945 /**

   946  * Determine whether a field has any data.

   947  *

   948  * @param $field

   949  *   A field structure.

   950  * @return

   951  *   TRUE if the field has data for any entity; FALSE otherwise.

   952  */

   953 function field_has_data($field) {

   954   $query = new EntityFieldQuery();

   955   $query = $query->fieldCondition($field)

   956     ->range(0, 1)

   957     ->count()

   958     // Neutralize the 'entity_field_access' query tag added by

   959     // field_sql_storage_field_storage_query(). The result cannot depend on the

   960     // access grants of the current user.

   961     ->addTag('DANGEROUS_ACCESS_CHECK_OPT_OUT');

   962 

   963   return (bool) $query

   964     ->execute() || (bool) $query

   965     ->age(FIELD_LOAD_REVISION)

   966     ->execute();

   967 }

   968 

   969 /**

   970  * Determine whether the user has access to a given field.

   971  *

   972  * This function does not determine whether access is granted to the entity

   973  * itself, only the specific field. Callers are responsible for ensuring that

   974  * entity access is also respected. For example, when checking field access for

   975  * nodes, check node_access() before checking field_access(), and when checking

   976  * field access for entities using the Entity API contributed module,

   977  * check entity_access() before checking field_access().

   978  *

   979  * @param $op

   980  *   The operation to be performed. Possible values:

   981  *   - 'edit'

   982  *   - 'view'

   983  * @param $field

   984  *   The full field structure array for the field on which the operation is to

   985  *   be performed. See field_info_field().

   986  * @param $entity_type

   987  *   The type of $entity; e.g., 'node' or 'user'.

   988  * @param $entity

   989  *   (optional) The entity for the operation.

   990  * @param $account

   991  *   (optional) The account to check, if not given use currently logged in user.

   992  *

   993  * @return

   994  *   TRUE if the operation is allowed;

   995  *   FALSE if the operation is denied.

   996  */

   997 function field_access($op, $field, $entity_type, $entity = NULL, $account = NULL) {

   998   global $user;

   999 

  1000   if (!isset($account)) {

  1001     $account = $user;

  1002   }

  1003 

  1004   foreach (module_implements('field_access') as $module) {

  1005     $function = $module . '_field_access';

  1006     $access = $function($op, $field, $entity_type, $entity, $account);

  1007     if ($access === FALSE) {

  1008       return FALSE;

  1009     }

  1010   }

  1011   return TRUE;

  1012 }

  1013 

  1014 /**

  1015  * Helper function to extract the bundle name of from a bundle object.

  1016  *

  1017  * @param $entity_type

  1018  *   The type of $entity; e.g., 'node' or 'user'.

  1019  * @param $bundle

  1020  *   The bundle object (or string if bundles for this entity type do not exist

  1021  *   as standalone objects).

  1022  * @return

  1023  *   The bundle name.

  1024  */

  1025 function field_extract_bundle($entity_type, $bundle) {

  1026   if (is_string($bundle)) {

  1027     return $bundle;

  1028   }

  1029 

  1030   $info = entity_get_info($entity_type);

  1031   if (is_object($bundle) && isset($info['bundle keys']['bundle']) && isset($bundle->{$info['bundle keys']['bundle']})) {

  1032     return $bundle->{$info['bundle keys']['bundle']};

  1033   }

  1034 }

  1035 

  1036 /**

  1037  * Theme preprocess function for theme_field() and field.tpl.php.

  1038  *

  1039  * @see theme_field()

  1040  * @see field.tpl.php

  1041  */

  1042 function template_preprocess_field(&$variables, $hook) {

  1043   $element = $variables['element'];

  1044 

  1045   // There's some overhead in calling check_plain() so only call it if the label

  1046   // variable is being displayed. Otherwise, set it to NULL to avoid PHP

  1047   // warnings if a theme implementation accesses the variable even when it's

  1048   // supposed to be hidden. If a theme implementation needs to print a hidden

  1049   // label, it needs to supply a preprocess function that sets it to the

  1050   // sanitized element title or whatever else is wanted in its place.

  1051   $variables['label_hidden'] = ($element['#label_display'] == 'hidden');

  1052   $variables['label'] = $variables['label_hidden'] ? NULL : check_plain($element['#title']);

  1053 

  1054   // We want other preprocess functions and the theme implementation to have

  1055   // fast access to the field item render arrays. The item render array keys

  1056   // (deltas) should always be a subset of the keys in #items, and looping on

  1057   // those keys is faster than calling element_children() or looping on all keys

  1058   // within $element, since that requires traversal of all element properties.

  1059   $variables['items'] = array();

  1060   foreach ($element['#items'] as $delta => $item) {

  1061     if (!empty($element[$delta])) {

  1062       $variables['items'][$delta] = $element[$delta];

  1063     }

  1064   }

  1065 

  1066   // Add default CSS classes. Since there can be many fields rendered on a page,

  1067   // save some overhead by calling strtr() directly instead of

  1068   // drupal_html_class().

  1069   $variables['field_name_css'] = strtr($element['#field_name'], '_', '-');

  1070   $variables['field_type_css'] = strtr($element['#field_type'], '_', '-');

  1071   $variables['classes_array'] = array(

  1072     'field',

  1073     'field-name-' . $variables['field_name_css'],

  1074     'field-type-' . $variables['field_type_css'],

  1075     'field-label-' . $element['#label_display'],

  1076   );

  1077   // Add a "clearfix" class to the wrapper since we float the label and the

  1078   // field items in field.css if the label is inline.

  1079   if ($element['#label_display'] == 'inline') {

  1080     $variables['classes_array'][] = 'clearfix';

  1081   }

  1082 

  1083   // Add specific suggestions that can override the default implementation.

  1084   $variables['theme_hook_suggestions'] = array(

  1085     'field__' . $element['#field_type'],

  1086     'field__' . $element['#field_name'],

  1087     'field__' . $element['#bundle'],

  1088     'field__' . $element['#field_name'] . '__' . $element['#bundle'],

  1089   );

  1090 }

  1091 

  1092 /**

  1093  * Theme process function for theme_field() and field.tpl.php.

  1094  *

  1095  * @see theme_field()

  1096  * @see field.tpl.php

  1097  */

  1098 function template_process_field(&$variables, $hook) {

  1099   // The default theme implementation is a function, so template_process() does

  1100   // not automatically run, so we need to flatten the classes and attributes

  1101   // here. For best performance, only call drupal_attributes() when needed, and

  1102   // note that template_preprocess_field() does not initialize the

  1103   // *_attributes_array variables.

  1104   $variables['classes'] = implode(' ', $variables['classes_array']);

  1105   $variables['attributes'] = empty($variables['attributes_array']) ? '' : drupal_attributes($variables['attributes_array']);

  1106   $variables['title_attributes'] = empty($variables['title_attributes_array']) ? '' : drupal_attributes($variables['title_attributes_array']);

  1107   $variables['content_attributes'] = empty($variables['content_attributes_array']) ? '' : drupal_attributes($variables['content_attributes_array']);

  1108   foreach ($variables['items'] as $delta => $item) {

  1109     $variables['item_attributes'][$delta] = empty($variables['item_attributes_array'][$delta]) ? '' : drupal_attributes($variables['item_attributes_array'][$delta]);

  1110   }

  1111 }

  1112 /**

  1113  * @} End of "defgroup field".

  1114  */

  1115 

  1116 /**

  1117  * Returns HTML for a field.

  1118  *

  1119  * This is the default theme implementation to display the value of a field.

  1120  * Theme developers who are comfortable with overriding theme functions may do

  1121  * so in order to customize this markup. This function can be overridden with

  1122  * varying levels of specificity. For example, for a field named 'body'

  1123  * displayed on the 'article' content type, any of the following functions will

  1124  * override this default implementation. The first of these functions that

  1125  * exists is used:

  1126  * - THEMENAME_field__body__article()

  1127  * - THEMENAME_field__article()

  1128  * - THEMENAME_field__body()

  1129  * - THEMENAME_field()

  1130  *

  1131  * Theme developers who prefer to customize templates instead of overriding

  1132  * functions may copy the "field.tpl.php" from the "modules/field/theme" folder

  1133  * of the Drupal installation to somewhere within the theme's folder and

  1134  * customize it, just like customizing other Drupal templates such as

  1135  * page.tpl.php or node.tpl.php. However, it takes longer for the server to

  1136  * process templates than to call a function, so for websites with many fields