node.api.php 40.4 KB
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<?php
// $Id$

/**
 * @file
 * Hooks provided by the Node module.
 */

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/**
 * @defgroup node_api_hooks Node API Hooks
 * @{
 * The Node API allows modules to define content types, to modify content
 * types created in the user interface, and to modify content types created by
 * other modules.
 *
 * Each content type is maintained by a primary module, which is either
 * node.module (for content types created in the user interface) or the
 * module that implements hook_node_info() to define the content type.
 *
 * During node operations (create, update, view, delete, etc.), there are
 * several sets of hooks that get invoked to allow modules to modify the base
 * node operation:
 * - Node-type-specific hooks: These hooks are only invoked on the primary
 *   module, using the "base" return component of hook_node_info() as the
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 *   function prefix.  For example, poll.module defines the base for the Poll
 *   content type as "poll", so during creation of a poll node, hook_insert() is
 *   only invoked by calling poll_insert().
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 * - All-module hooks: This set of hooks is invoked on all implementing
 *   modules, to allow other modules to modify what the primary node module is
 *   doing. For example, hook_node_insert() is invoked on all modules when
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 *   creating a poll node.
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 * - Field hooks: Hooks related to the fields attached to the node. These are
 *   invoked from the field operations functions described below, and can be
 *   either field-type-specific or all-module hooks.
 * - Entity hooks: Generic hooks for "entity" operations. These are always
 *   invoked on all modules.
 *
 * Here is a list of the node and entity hooks that are invoked, field
 * operations, and other steps that take place during node operations:
 * - Creating a new node (calling node_save() on a new node):
 *   - field_attach_presave()
 *   - hook_node_presave() (all)
 *   - Node and revision records are written to the database
 *   - hook_insert() (node-type-specific)
 *   - field_attach_insert()
 *   - hook_node_insert() (all)
 *   - hook_entity_insert() (all)
 *   - hook_node_access_records() (all)
 *   - hook_node_access_records_alter() (all)
 * - Updating an existing node (calling node_save() on an existing node):
 *   - field_attach_presave()
 *   - hook_node_presave() (all)
 *   - Node and revision records are written to the database
 *   - hook_update() (node-type-specific)
 *   - field_attach_update()
 *   - hook_node_update() (all)
 *   - hook_entity_update() (all)
 *   - hook_node_access_records() (all)
 *   - hook_node_access_records_alter() (all)
 * - Loading a node (calling node_load(), node_load_multiple(), or
 *   entity_load() with $entity_type of 'node'):
 *   - Node and revision information is read from database.
 *   - hook_load() (node-type-specific)
 *   - field_attach_load_revision() and field_attach_load()
 *   - hook_entity_load() (all)
 *   - hook_node_load() (all)
 * - Viewing a single node (calling node_view() - note that the input to
 *   node_view() is a loaded node, so the Loading steps above are already
 *   done):
 *   - hook_view() (node-type-specific)
 *   - field_attach_prepare_view()
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 *   - hook_entity_prepare_view() (all)
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 *   - field_attach_view()
 *   - hook_node_view() (all)
 * - Viewing multiple nodes (calling node_view_multiple() - note that the input
 *   to node_view_multiple() is a set of loaded nodes, so the Loading steps
 *   above are already done):
 *   - field_attach_prepare_view()
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 *   - hook_entity_prepare_view() (all)
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 *   - hook_view() (node-type-specific)
 *   - field_attach_view()
 *   - hook_node_view() (all)
 *   - hook_node_view_alter() (all)
 * - Deleting a node (calling node_delete() or node_delete_multiple()):
 *   - Node is loaded (see Loading section above)
 *   - Node and revision information is deleted from database
 *   - hook_delete() (node-type-specific)
 *   - hook_node_delete() (all)
 *   - field_attach_delete()
 * - Deleting a node revision (calling node_revision_delete()):
 *   - Node is loaded (see Loading section above)
 *   - Revision information is deleted from database
 *   - hook_node_revision_delete() (all)
 *   - field_attach_delete_revision()
 * - Preparing a node for editing (calling node_form() - note that if it's
 *   an existing node, it will already be loaded; see the Loading section
 *   above):
 *   - hook_prepare() (node-type-specific)
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 *   - hook_node_prepare() (all)
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 *   - hook_form() (node-type-specific)
 *   - field_attach_form()
 * - Validating a node during editing form submit (calling
 *   node_form_validate()):
 *   - hook_validate() (node-type-specific)
 *   - hook_node_validate() (all)
 *   - field_attach_form_validate()
 * - Searching (calling node_search_execute()):
 *   - hook_ranking() (all)
 *   - Query is executed to find matching nodes
 *   - Resulting node is loaded (see Loading section above)
 *   - Resulting node is prepared for viewing (see Viewing a single node above)
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 *   - comment_node_update_index() is called.
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 *   - hook_node_search_result() (all)
 * - Search indexing (calling node_update_index()):
 *   - Node is loaded (see Loading section above)
 *   - Node is prepared for viewing (see Viewing a single node above)
 *   - hook_node_update_index() (all)
 * @}
 */

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/**
 * @addtogroup hooks
 * @{
 */

/**
 * Inform the node access system what permissions the user has.
 *
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 * This hook is for implementation by node access modules. In this hook,
 * the module grants a user different "grant IDs" within one or more
 * "realms". In hook_node_access_records(), the realms and grant IDs are
 * associated with permission to view, edit, and delete individual nodes.
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 *
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 * The realms and grant IDs can be arbitrarily defined by your node access
 * module; it is common to use role IDs as grant IDs, but that is not
 * required. Your module could instead maintain its own list of users, where
 * each list has an ID. In that case, the return value of this hook would be
 * an array of the list IDs that this user is a member of.
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 *
 * A node access module may implement as many realms as necessary to
 * properly define the access privileges for the nodes.
 *
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 * @param $account
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 *   The user object whose grants are requested.
 * @param $op
 *   The node operation to be performed, such as "view", "update", or "delete".
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 *
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 * @return
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 *   An array whose keys are "realms" of grants, and whose values are arrays of
 *   the grant IDs within this realm that this user is being granted.
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 *
 * For a detailed example, see node_access_example.module.
 *
 * @ingroup node_access
 */
function hook_node_grants($account, $op) {
  if (user_access('access private content', $account)) {
    $grants['example'] = array(1);
  }
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  $grants['example_owner'] = array($account->uid);
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  return $grants;
}

/**
 * Set permissions for a node to be written to the database.
 *
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 * When a node is saved, a module implementing hook_node_access_records() will
 * be asked if it is interested in the access permissions for a node. If it is
 * interested, it must respond with an array of permissions arrays for that
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 * node.
 *
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 * Note that the grant values in the return value from your hook must be
 * integers and not boolean TRUE and FALSE.
 *
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 * Each permissions item in the array is an array with the following elements:
 * - 'realm': The name of a realm that the module has defined in
 *   hook_node_grants().
 * - 'gid': A 'grant ID' from hook_node_grants().
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 * - 'grant_view': If set to 1 a user that has been identified as a member
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 *   of this gid within this realm can view this node.
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 * - 'grant_update': If set to 1 a user that has been identified as a member
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 *   of this gid within this realm can edit this node.
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 * - 'grant_delete': If set to 1 a user that has been identified as a member
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 *   of this gid within this realm can delete this node.
 * - 'priority': If multiple modules seek to set permissions on a node, the
 *   realms that have the highest priority will win out, and realms with a lower
 *   priority will not be written. If there is any doubt, it is best to
 *   leave this 0.
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 *
 * @ingroup node_access
 */
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function hook_node_access_records($node) {
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  if (node_access_example_disabling()) {
    return;
  }

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  // We only care about the node if it has been marked private. If not, it is
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  // treated just like any other node and we completely ignore it.
  if ($node->private) {
    $grants = array();
    $grants[] = array(
      'realm' => 'example',
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      'gid' => 1,
      'grant_view' => 1,
      'grant_update' => 0,
      'grant_delete' => 0,
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      'priority' => 0,
    );

    // For the example_author array, the GID is equivalent to a UID, which
    // means there are many many groups of just 1 user.
    $grants[] = array(
      'realm' => 'example_author',
      'gid' => $node->uid,
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      'grant_view' => 1,
      'grant_update' => 1,
      'grant_delete' => 1,
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      'priority' => 0,
    );
    return $grants;
  }
}

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/**
 * Alter permissions for a node before it is written to the database.
 *
 * Node access modules establish rules for user access to content. Node access
 * records are stored in the {node_access} table and define which permissions
 * are required to access a node. This hook is invoked after node access modules
 * returned their requirements via hook_node_access_records(); doing so allows
 * modules to modify the $grants array by reference before it is stored, so
 * custom or advanced business logic can be applied.
 *
 * @see hook_node_access_records()
 *
 * Upon viewing, editing or deleting a node, hook_node_grants() builds a
 * permissions array that is compared against the stored access records. The
 * user must have one or more matching permissions in order to complete the
 * requested operation.
 *
 * @see hook_node_grants()
 * @see hook_node_grants_alter()
 *
 * @param &$grants
 *   The $grants array returned by hook_node_access_records().
 * @param $node
 *   The node for which the grants were acquired.
 *
 * The preferred use of this hook is in a module that bridges multiple node
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 * access modules with a configurable behavior, as shown in the example with the
 * 'is_preview' field.
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 *
 * @ingroup node_access
 */
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function hook_node_access_records_alter(&$grants, $node) {
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  // Our module allows editors to mark specific articles with the 'is_preview'
  // field. If the node being saved has a TRUE value for that field, then only
  // our grants are retained, and other grants are removed. Doing so ensures
  // that our rules are enforced no matter what priority other grants are given.
  if ($node->is_preview) {
    // Our module grants are set in $grants['example'].
    $temp = $grants['example'];
    // Now remove all module grants but our own.
    $grants = array('example' => $temp);
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  }
}

/**
 * Alter user access rules when trying to view, edit or delete a node.
 *
 * Node access modules establish rules for user access to content.
 * hook_node_grants() defines permissions for a user to view, edit or
 * delete nodes by building a $grants array that indicates the permissions
 * assigned to the user by each node access module. This hook is called to allow
 * modules to modify the $grants array by reference, so the interaction of
 * multiple node access modules can be altered or advanced business logic can be
 * applied.
 *
 * @see hook_node_grants()
 *
 * The resulting grants are then checked against the records stored in the
 * {node_access} table to determine if the operation may be completed.
 *
 * @see hook_node_access_records()
 * @see hook_node_access_records_alter()
 *
 * @param &$grants
 *   The $grants array returned by hook_node_grants().
 * @param $account
 *   The user account requesting access to content.
 * @param $op
 *   The operation being performed, 'view', 'update' or 'delete'.
 *
 * Developers may use this hook to either add additional grants to a user
 * or to remove existing grants. These rules are typically based on either the
 * permissions assigned to a user role, or specific attributes of a user
 * account.
 *
 * @ingroup node_access
 */
function hook_node_grants_alter(&$grants, $account, $op) {
  // Our sample module never allows certain roles to edit or delete
  // content. Since some other node access modules might allow this
  // permission, we expressly remove it by returning an empty $grants
  // array for roles specified in our variable setting.

  // Get our list of banned roles.
  $restricted = variable_get('example_restricted_roles', array());
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  if ($op != 'view' && !empty($restricted)) {
    // Now check the roles for this account against the restrictions.
    foreach ($restricted as $role_id) {
      if (isset($user->roles[$role_id])) {
        $grants = array();
      }
    }
  }
}

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/**
 * Add mass node operations.
 *
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 * This hook enables modules to inject custom operations into the mass
 * operations dropdown found at admin/content, by associating a callback
 * function with the operation, which is called when the form is submitted. The
 * callback function receives one initial argument, which is an array of the
 * checked nodes.
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 *
 * @return
 *   An array of operations. Each operation is an associative array that may
 *   contain the following key-value pairs:
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 *   - 'label': Required. The label for the operation, displayed in the dropdown
 *     menu.
 *   - 'callback': Required. The function to call for the operation.
 *   - 'callback arguments': Optional. An array of additional arguments to pass
 *     to the callback function.
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 */
function hook_node_operations() {
  $operations = array(
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    'publish' => array(
      'label' => t('Publish selected content'),
      'callback' => 'node_mass_update',
      'callback arguments' => array('updates' => array('status' => NODE_PUBLISHED)),
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    ),
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    'unpublish' => array(
      'label' => t('Unpublish selected content'),
      'callback' => 'node_mass_update',
      'callback arguments' => array('updates' => array('status' => NODE_NOT_PUBLISHED)),
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    ),
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    'promote' => array(
      'label' => t('Promote selected content to front page'),
      'callback' => 'node_mass_update',
      'callback arguments' => array('updates' => array('status' => NODE_PUBLISHED, 'promote' => NODE_PROMOTED)),
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    ),
    'demote' => array(
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      'label' => t('Demote selected content from front page'),
      'callback' => 'node_mass_update',
      'callback arguments' => array('updates' => array('promote' => NODE_NOT_PROMOTED)),
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    ),
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    'sticky' => array(
      'label' => t('Make selected content sticky'),
      'callback' => 'node_mass_update',
      'callback arguments' => array('updates' => array('status' => NODE_PUBLISHED, 'sticky' => NODE_STICKY)),
    ),
    'unsticky' => array(
      'label' => t('Make selected content not sticky'),
      'callback' => 'node_mass_update',
      'callback arguments' => array('updates' => array('sticky' => NODE_NOT_STICKY)),
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    ),
    'delete' => array(
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      'label' => t('Delete selected content'),
      'callback' => NULL,
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    ),
  );
  return $operations;
}

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/**
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 * Respond to node deletion.
 *
 * This hook is invoked from node_delete_multiple() after the node has been
 * removed from the node table in the database, after the type-specific
 * hook_delete() has been invoked, and before field_attach_delete() is called.
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 *
 * @param $node
 *   The node that is being deleted.
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 *
 * @ingroup node_api_hooks
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 */
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function hook_node_delete($node) {
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  db_delete('mytable')
    ->condition('nid', $node->nid)
    ->execute();
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}

/**
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 * Respond to deletion of a node revision.
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 *
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 * This hook is invoked from node_revision_delete() after the revision has been
 * removed from the node_revision table, and before
 * field_attach_delete_revision() is called.
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 *
 * @param $node
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 *   The node revision (node object) that is being deleted.
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 *
 * @ingroup node_api_hooks
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 */
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function hook_node_revision_delete($node) {
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  db_delete('upload')->condition('vid', $node->vid)->execute();
  if (!is_array($node->files)) {
    return;
  }
  foreach ($node->files as $file) {
    file_delete($file);
  }
}

/**
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 * Respond to creation of a new node.
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 *
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 * This hook is invoked from node_save() after the node is inserted into the
 * node table in the database, after the type-specific hook_insert() is invoked,
 * and after field_attach_insert() is called.
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 *
 * @param $node
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 *   The node that is being created.
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 *
 * @ingroup node_api_hooks
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 */
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function hook_node_insert($node) {
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  db_insert('mytable')
    ->fields(array(
      'nid' => $node->nid,
      'extra' => $node->extra,
    ))
    ->execute();
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}

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/**
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 * Act on nodes being loaded from the database.
 *
 * This hook is invoked during node loading, which is handled by entity_load(),
 * via classes NodeController and DrupalDefaultEntityController. After the node
 * information is read from the database or the entity cache, hook_load() is
 * invoked on the node's content type module, then field_attach_node_revision()
 * or field_attach_load() is called, then hook_entity_load() is invoked on all
 * implementing modules, and finally hook_node_load() is invoked on all
 * implementing modules.
 *
 * This hook should only be used to add information that is not in the node or
 * node revisions table, not to replace information that is in these tables
 * (which could interfere with the entity cache). For performance reasons,
 * information for all available nodes should be loaded in a single query where
 * possible.
 *
 * The $types parameter allows for your module to have an early return (for
 * efficiency) if your module only supports certain node types. However, if your
 * module defines a content type, you can use hook_load() to respond to loading
 * of just that content type.
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 *
 * @param $nodes
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 *   An array of the nodes being loaded, keyed by nid.
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 * @param $types
 *   An array containing the types of the nodes.
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 *
 * For a detailed usage example, see nodeapi_example.module.
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 *
 * @ingroup node_api_hooks
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 */
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function hook_node_load($nodes, $types) {
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  $result = db_query('SELECT nid, foo FROM {mytable} WHERE nid IN(:nids)', array(':nids' => array_keys($nodes)));
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  foreach ($result as $record) {
    $nodes[$record->nid]->foo = $record->foo;
  }
}

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/**
 * Control access to a node.
 *
 * Modules may implement this hook if they want to have a say in whether or not
 * a given user has access to perform a given operation on a node.
 *
 * The administrative account (user ID #1) always passes any access check,
 * so this hook is not called in that case. Users with the "bypass node access"
 * permission may always view and edit content through the administrative
 * interface.
 *
 * Note that not all modules will want to influence access on all
 * node types. If your module does not want to actively grant or
 * block access, return NODE_ACCESS_IGNORE or simply return nothing.
 * Blindly returning FALSE will break other node access modules.
 *
 * @link http://api.drupal.org/api/group/node_access/7 More on the node access system @endlink
 * @ingroup node_access
 * @param $node
 *   The node on which the operation is to be performed, or, if it does
 *   not yet exist, the type of node to be created.
 * @param $op
 *   The operation to be performed. Possible values:
 *   - "create"
 *   - "delete"
 *   - "update"
 *   - "view"
 * @param $account
 *   A user object representing the user for whom the operation is to be
 *   performed.
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 *
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 * @return
 *   NODE_ACCESS_ALLOW if the operation is to be allowed;
 *   NODE_ACCESS_DENY if the operation is to be denied;
 *   NODE_ACCESSS_IGNORE to not affect this operation at all.
 */
function hook_node_access($node, $op, $account) {
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  $type = is_string($node) ? $node : $node->type;
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  if (in_array($type, node_permissions_get_configured_types())) {
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    if ($op == 'create' && user_access('create ' . $type . ' content', $account)) {
      return NODE_ACCESS_ALLOW;
    }

    if ($op == 'update') {
      if (user_access('edit any ' . $type . ' content', $account) || (user_access('edit own ' . $type . ' content', $account) && ($account->uid == $node->uid))) {
        return NODE_ACCESS_ALLOW;
      }
    }

    if ($op == 'delete') {
      if (user_access('delete any ' . $type . ' content', $account) || (user_access('delete own ' . $type . ' content', $account) && ($account->uid == $node->uid))) {
        return NODE_ACCESS_ALLOW;
      }
    }
  }

  // Returning nothing from this function would have the same effect.
  return NODE_ACCESS_IGNORE;
}


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/**
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 * Act on a node object about to be shown on the add/edit form.
 *
 * This hook is invoked from node_object_prepare() after the type-specific
 * hook_prepare() is invoked.
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 *
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 * @param $node
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 *   The node that is about to be shown on the add/edit form.
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 *
 * @ingroup node_api_hooks
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 */
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function hook_node_prepare($node) {
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  if (!isset($node->comment)) {
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    $node->comment = variable_get("comment_$node->type", COMMENT_NODE_OPEN);
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  }
}

/**
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 * Act on a node being displayed as a search result.
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 *
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 * This hook is invoked from node_search_execute(), after node_load()
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 * and node_view() have been called.
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 *
 * @param $node
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 *   The node being displayed in a search result.
 *
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 * @return
 *   Extra information to be displayed with search result.
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 *
 * @ingroup node_api_hooks
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 */
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function hook_node_search_result($node) {
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  $comments = db_query('SELECT comment_count FROM {node_comment_statistics} WHERE nid = :nid', array('nid' => $node->nid))->fetchField();
  return format_plural($comments, '1 comment', '@count comments');
}

/**
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 * Act on a node being inserted or updated.
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 *
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 * This hook is invoked from node_save() before the node is saved to the
 * database.
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 *
 * @param $node
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 *   The node that is being inserted or updated.
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 *
 * @ingroup node_api_hooks
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 */
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function hook_node_presave($node) {
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  if ($node->nid && $node->moderate) {
    // Reset votes when node is updated:
    $node->score = 0;
    $node->users = '';
    $node->votes = 0;
  }
}

/**
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 * Respond to updates to a node.
 *
 * This hook is invoked from node_save() after the node is updated in the node
 * table in the database, after the type-specific hook_update() is invoked, and
 * after field_attach_update() is called.
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 *
 * @param $node
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 *   The node that is being updated.
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 *
 * @ingroup node_api_hooks
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 */
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function hook_node_update($node) {
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  db_update('mytable')
    ->fields(array('extra' => $node->extra))
    ->condition('nid', $node->nid)
    ->execute();
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}

/**
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 * Act on a node being indexed for searching.
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 *
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 * This hook is invoked during search indexing, after node_load(), and after
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 * the result of node_view() is added as $node->rendered to the node object.
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 *
 * @param $node
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 *   The node being indexed.
 *
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 * @return
 *   Array of additional information to be indexed.
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 *
 * @ingroup node_api_hooks
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 */
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function hook_node_update_index($node) {
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  $text = '';
  $comments = db_query('SELECT subject, comment, format FROM {comment} WHERE nid = :nid AND status = :status', array(':nid' => $node->nid, ':status' => COMMENT_PUBLISHED));
  foreach ($comments as $comment) {
632
    $text .= '<h2>' . check_plain($comment->subject) . '</h2>' . check_markup($comment->comment, $comment->format, '', TRUE);
633 634 635 636 637
  }
  return $text;
}

/**
638 639 640 641 642 643
 * Perform node validation before a node is created or updated.
 *
 * This hook is invoked from node_validate(), after a user has has finished
 * editing the node and is previewing or submitting it. It is invoked at the
 * end of all the standard validation steps, and after the type-specific
 * hook_validate() is invoked.
644
 *
645 646 647 648 649 650
 * To indicate a validation error, use form_set_error().
 *
 * Note: Changes made to the $node object within your hook implementation will
 * have no effect.  The preferred method to change a node's content is to use
 * hook_node_presave() instead. If it is really necessary to change
 * the node at the validate stage, you can use form_set_value().
651 652
 *
 * @param $node
653
 *   The node being validated.
654
 * @param $form
655
 *   The form being used to edit the node.
656 657
 *
 * @ingroup node_api_hooks
658
 */
659
function hook_node_validate($node, $form) {
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  if (isset($node->end) && isset($node->start)) {
    if ($node->start > $node->end) {
      form_set_error('time', t('An event may not end before it starts.'));
    }
  }
}

/**
668
 * Act on a node that is being assembled before rendering.
669
 *
670 671 672 673
 * The module may add elements to $node->content prior to rendering. This hook
 * will be called after hook_view(). The structure of $node->content is a
 * renderable array as expected by drupal_render().
 *
674
 * When $view_mode is 'rss', modules can also add extra RSS elements and
675 676
 * namespaces to $node->rss_elements and $node->rss_namespaces respectively for
 * the RSS item generated for this node.
677
 * For details on how this is used, see node_feed().
678 679 680 681
 *
 * @see taxonomy_node_view()
 * @see upload_node_view()
 * @see comment_node_view()
682 683
 *
 * @param $node
684
 *   The node that is being assembled for rendering.
685 686
 * @param $view_mode
 *   The $view_mode parameter from node_view().
687 688
 *
 * @ingroup node_api_hooks
689
 */
690
function hook_node_view($node, $view_mode) {
691
  $node->content['my_additional_field'] = array(
692
    '#markup' => $additional_field,
693
    '#weight' => 10,
694
    '#theme' => 'mymodule_my_additional_field',
695
  );
696 697
}

698
/**
699
 * Alter the results of node_view().
700
 *
701 702 703
 * This hook is called after the content has been assembled in a structured
 * array and may be used for doing processing which requires that the complete
 * node content structure has been built.
704 705
 *
 * If the module wishes to act on the rendered HTML of the node rather than the
706 707
 * structured content array, it may use this hook to add a #post_render
 * callback.  Alternatively, it could also implement hook_preprocess_node(). See
708 709
 * drupal_render() and theme() documentation respectively for details.
 *
710 711 712
 * @param $build
 *   A renderable array representing the node content.
 *
713
 * @see node_view()
714 715
 *
 * @ingroup node_api_hooks
716
 */
717
function hook_node_view_alter(&$build) {
718
  if ($build['#view_mode'] == 'full' && isset($build['an_additional_field'])) {
719
    // Change its weight.
720
    $build['an_additional_field']['#weight'] = -10;
721
  }
722 723

  // Add a #post_render callback to act on the rendered HTML of the node.
724
  $build['#post_render'][] = 'my_module_node_post_render';
725 726
}

727
/**
728
 * Define module-provided node types.
729
 *
730 731 732 733
 * This hook allows a module to define one or more of its own node types. For
 * example, the blog module uses it to define a blog node-type named "Blog
 * entry." The name and attributes of each desired node type are specified in
 * an array returned by the hook.
734
 *
735 736 737 738 739 740
 * Only module-provided node types should be defined through this hook. User-
 * provided (or 'custom') node types should be defined only in the 'node_type'
 * database table, and should be maintained by using the node_type_save() and
 * node_type_delete() functions.
 *
 * @return
741 742 743 744
 *   An array of information defining the module's node types. The array
 *   contains a sub-array for each node type, with the machine-readable type
 *   name as the key. Each sub-array has up to 10 attributes. Possible
 *   attributes:
745
 *   - "name": the human-readable name of the node type. Required.
746 747 748
 *   - "base": the base string used to construct callbacks corresponding to
 *      this node type.
 *      (i.e. if base is defined as example_foo, then example_foo_insert will
749
 *      be called when inserting a node of that type). This string is usually
750
 *      the name of the module, but not always. Required.
751
 *   - "description": a brief description of the node type. Required.
752 753
 *   - "help": help information shown to the user when creating a node of
 *      this type.. Optional (defaults to '').
754 755 756 757
 *   - "has_title": boolean indicating whether or not this node type has a title
 *      field. Optional (defaults to TRUE).
 *   - "title_label": the label for the title field of this content type.
 *      Optional (defaults to 'Title').
758
 *   - "locked": boolean indicating whether the administrator can change the
759 760
 *      machine name of this type. FALSE = changeable (not locked),
 *      TRUE = unchangeable (locked). Optional (defaults to TRUE).
761 762 763
 *
 * The machine-readable name of a node type should contain only letters,
 * numbers, and underscores. Underscores will be converted into hyphens for the
764
 * purpose of constructing URLs.
765 766 767 768 769 770
 *
 * All attributes of a node type that are defined through this hook (except for
 * 'locked') can be edited by a site administrator. This includes the
 * machine-readable name of a node type, if 'locked' is set to FALSE.
 *
 * For a detailed usage example, see node_example.module.
771 772
 *
 * @ingroup node_api_hooks
773 774 775
 */
function hook_node_info() {
  return array(
776 777 778 779
    'blog' => array(
      'name' => t('Blog entry'),
      'base' => 'blog',
      'description' => t('Use for multi-user blogs. Every user gets a personal blog.'),
780 781 782 783
    )
  );
}

784 785 786 787 788 789 790 791 792 793 794 795 796 797 798 799 800 801 802 803 804 805 806 807 808 809 810 811 812 813 814 815 816 817 818 819 820
/**
 * Provide additional methods of scoring for core search results for nodes.
 *
 * A node's search score is used to rank it among other nodes matched by the
 * search, with the highest-ranked nodes appearing first in the search listing.
 *
 * For example, a module allowing users to vote on content could expose an
 * option to allow search results' rankings to be influenced by the average
 * voting score of a node.
 *
 * All scoring mechanisms are provided as options to site administrators, and
 * may be tweaked based on individual sites or disabled altogether if they do
 * not make sense. Individual scoring mechanisms, if enabled, are assigned a
 * weight from 1 to 10. The weight represents the factor of magnification of
 * the ranking mechanism, with higher-weighted ranking mechanisms having more
 * influence. In order for the weight system to work, each scoring mechanism
 * must return a value between 0 and 1 for every node. That value is then
 * multiplied by the administrator-assigned weight for the ranking mechanism,
 * and then the weighted scores from all ranking mechanisms are added, which
 * brings about the same result as a weighted average.
 *
 * @return
 *   An associative array of ranking data. The keys should be strings,
 *   corresponding to the internal name of the ranking mechanism, such as
 *   'recent', or 'comments'. The values should be arrays themselves, with the
 *   following keys available:
 *   - "title": the human readable name of the ranking mechanism. Required.
 *   - "join": part of a query string to join to any additional necessary
 *     table. This is not necessary if the table required is already joined to
 *     by the base query, such as for the {node} table. Other tables should use
 *     the full table name as an alias to avoid naming collisions. Optional.
 *   - "score": part of a query string to calculate the score for the ranking
 *     mechanism based on values in the database. This does not need to be
 *     wrapped in parentheses, as it will be done automatically; it also does
 *     not need to take the weighted system into account, as it will be done
 *     automatically. It does, however, need to calculate a decimal between
 *     0 and 1; be careful not to cast the entire score to an integer by
821
 *     inadvertently introducing a variable argument. Required.
822 823
 *   - "arguments": if any arguments are required for the score, they can be
 *     specified in an array here.
824 825
 *
 * @ingroup node_api_hooks
826 827 828 829 830 831 832 833 834 835 836 837 838 839 840 841 842 843 844 845 846
 */
function hook_ranking() {
  // If voting is disabled, we can avoid returning the array, no hard feelings.
  if (variable_get('vote_node_enabled', TRUE)) {
    return array(
      'vote_average' => array(
        'title' => t('Average vote'),
        // Note that we use i.sid, the search index's search item id, rather than
        // n.nid.
        'join' => 'LEFT JOIN {vote_node_data} vote_node_data ON vote_node_data.nid = i.sid',
        // The highest possible score should be 1, and the lowest possible score,
        // always 0, should be 0.
        'score' => 'vote_node_data.average / CAST(%f AS DECIMAL)',
        // Pass in the highest possible voting score as a decimal argument.
        'arguments' => array(variable_get('vote_score_max', 5)),
      ),
    );
  }
}


847
/**
848
 * Respond to node type creation.
849
 *
850 851
 * This hook is invoked from node_type_save() after the node type is added
 * to the database.
852 853
 *
 * @param $info
854
 *   The node type object that is being created.
855 856 857 858
 */
function hook_node_type_insert($info) {
}

859
/**
860
 * Respond to node type updates.
861
 *
862 863
 * This hook is invoked from node_type_save() after the node type is updated
 * in the database.
864 865
 *
 * @param $info
866
 *   The node type object that is being updated.
867
 */
868 869 870 871 872
function hook_node_type_update($info) {
  if (!empty($info->old_type) && $info->old_type != $info->type) {
    $setting = variable_get('comment_' . $info->old_type, COMMENT_NODE_OPEN);
    variable_del('comment_' . $info->old_type);
    variable_set('comment_' . $info->type, $setting);
873 874 875
  }
}

876
/**
877
 * Respond to node type deletion.
878
 *
879 880
 * This hook is invoked from node_type_delete() after the node type is removed
 * from the database.
881 882
 *
 * @param $info
883
 *   The node type object that is being deleted.
884 885 886 887 888
 */
function hook_node_type_delete($info) {
  variable_del('comment_' . $info->type);
}

889 890 891
/**
 * Respond to node deletion.
 *
892 893
 * This hook is invoked only on the module that defines the node's content type
 * (use hook_node_delete() to respond to all node deletions).
894
 *
895 896 897
 * This hook is invoked from node_delete_multiple() after the node has been
 * removed from the node table in the database, before hook_node_delete() is
 * invoked, and before field_attach_delete() is called.
898
 *
899 900
 * @param $node
 *   The node that is being deleted.
901 902
 *
 * @ingroup node_api_hooks
903
 */
904
function hook_delete($node) {
905 906 907
  db_delete('mytable')
    ->condition('nid', $nid->nid)
    ->execute();
908 909 910
}

/**
911
 * Act on a node object about to be shown on the add/edit form.
912
 *
913 914
 * This hook is invoked only on the module that defines the node's content type
 * (use hook_node_prepare() to act on all node preparations).
915
 *
916 917 918 919 920
 * This hook is invoked from node_object_prepare() before the general
 * hook_node_prepare() is invoked.
 *
 * @param $node
 *   The node that is about to be shown on the add/edit form.
921 922
 *
 * @ingroup node_api_hooks
923
 */
924
function hook_prepare($node) {
925 926 927
  if ($file = file_check_upload($field_name)) {
    $file = file_save_upload($field_name, _image_filename($file->filename, NULL, TRUE));
    if ($file) {
928
      if (!image_get_info($file->uri)) {
929 930 931 932 933 934 935
        form_set_error($field_name, t('Uploaded file is not a valid image'));
        return;
      }
    }
    else {
      return;
    }
936
    $node->images['_original'] = $file->uri;
937
    _image_build_derivatives($node, TRUE);
938 939 940 941 942 943 944 945 946 947 948
    $node->new_file = TRUE;
  }
}

/**
 * Display a node editing form.
 *
 * This hook, implemented by node modules, is called to retrieve the form
 * that is displayed when one attempts to "create/edit" an item. This form is
 * displayed at the URI http://www.example.com/?q=node/<add|edit>/nodetype.
 *
949
 * @param $node
950 951 952 953 954 955 956 957 958 959 960 961 962
 *   The node being added or edited.
 * @param $form_state
 *   The form state array. Changes made to this variable will have no effect.
 * @return
 *   An array containing the form elements to be displayed in the node
 *   edit form.
 *
 * The submit and preview buttons, taxonomy controls, and administrative
 * accoutrements are displayed automatically by node.module. This hook
 * needs to return the node title, the body text area, and fields
 * specific to the node type.
 *
 * For a detailed usage example, see node_example.module.
963 964
 *
 * @ingroup node_api_hooks
965
 */
966
function hook_form($node, $form_state) {
967
  $type = node_type_get_type($node);
968 969 970 971 972 973 974 975 976 977 978 979 980 981 982 983

  $form['field1'] = array(
    '#type' => 'textfield',
    '#title' => t('Custom field'),
    '#default_value' => $node->field1,
    '#maxlength' => 127,
  );
  $form['selectbox'] = array(
    '#type' => 'select',
    '#title' => t('Select box'),
    '#default_value' => $node->selectbox,
    '#options' => array(
      1 => 'Option A',
      2 => 'Option B',
      3 => 'Option C',
    ),
984
    '#description' => t('Choose an option.'),
985 986 987 988 989 990
  );

  return $form;
}

/**
991
 * Respond to creation of a new node.
992
 *
993 994
 * This hook is invoked only on the module that defines the node's content type
 * (use hook_node_insert() to act on all node insertions).
995
 *
996 997 998
 * This hook is invoked from node_save() after the node is inserted into the
 * node table in the database, before field_attach_insert() is called, and
 * before hook_node_insert() is invoked.
999
 *
1000 1001
 * @param $node
 *   The node that is being created.
1002 1003
 *
 * @ingroup node_api_hooks
1004
 */
1005
function hook_insert($node) {
1006 1007 1008 1009 1010 1011
  db_insert('mytable')
    ->fields(array(
      'nid' => $node->nid,
      'extra' => $node->extra,
    ))
    ->execute();
1012 1013 1014
}

/**
1015
 * Act on nodes being loaded from the database.
1016
 *
1017 1018 1019 1020 1021 1022 1023 1024 1025 1026 1027 1028 1029 1030 1031 1032
 * This hook is invoked only on the module that defines the node's content type
 * (use hook_node_load() to respond to all node loads).
 *
 * This hook is invoked during node loading, which is handled by entity_load(),
 * via classes NodeController and DrupalDefaultEntityController. After the node
 * information is read from the database or the entity cache, hook_load() is
 * invoked on the node's content type module, then field_attach_node_revision()
 * or field_attach_load() is called, then hook_entity_load() is invoked on all
 * implementing modules, and finally hook_node_load() is invoked on all
 * implementing modules.
 *
 * This hook should only be used to add information that is not in the node or
 * node revisions table, not to replace information that is in these tables
 * (which could interfere with the entity cache). For performance reasons,
 * information for all available nodes should be loaded in a single query where
 * possible.
1033
 *
1034
 * @param $nodes
1035
 *   An array of the nodes being loaded, keyed by nid.
1036 1037
 *
 * For a detailed usage example, see node_example.module.
1038 1039
 *
 * @ingroup node_api_hooks
1040
 */
1041
function hook_load($nodes) {
1042
  $result = db_query('SELECT nid, foo FROM {mytable} WHERE nid IN (:nids)', array(':nids' => array_keys($nodes)));
1043 1044 1045
  foreach ($result as $record) {
    $nodes[$record->nid]->foo = $record->foo;
  }
1046 1047 1048
}

/**
1049
 * Respond to updates to a node.
1050
 *
1051 1052
 * This hook is invoked only on the module that defines the node's content type
 * (use hook_node_update() to act on all node updates).
1053
 *
1054 1055 1056
 * This hook is invoked from node_save() after the node is updated in the
 * node table in the database, before field_attach_update() is called, and
 * before hook_node_update() is invoked.
1057
 *
1058 1059
 * @param $node
 *   The node that is being updated.
1060 1061
 *
 * @ingroup node_api_hooks
1062
 */
1063
function hook_update($node) {
1064 1065 1066 1067
  db_update('mytable')
    ->fields(array('extra' => $node->extra))
    ->condition('nid', $node->nid)
    ->execute();
1068 1069 1070
}

/**
1071
 * Perform node validation before a node is created or updated.
1072
 *
1073 1074
 * This hook is invoked only on the module that defines the node's content type
 * (use hook_node_validate() to act on all node validations).
1075
 *
1076
 * This hook is invoked from node_validate(), after a user has finished
1077 1078 1079
 * editing the node and is previewing or submitting it. It is invoked at the end
 * of all the standard validation steps, and before hook_node_validate() is
 * invoked.
1080
 *
1081
 * To indicate a validation error, use form_set_error().
1082
 *
1083 1084
 * Note: Changes made to the $node object within your hook implementation will
 * have no effect.  The preferred method to change a node's content is to use
1085
 * hook_node_presave() instead.
1086
 *
1087 1088 1089 1090
 * @param $node
 *   The node being validated.
 * @param $form
 *   The form being used to edit the node.
1091 1092
 *
 * @ingroup node_api_hooks
1093
 */
1094
function hook_validate($node, &$form) {
1095 1096 1097 1098 1099 1100 1101 1102 1103 1104 1105 1106 1107 1108 1109
  if (isset($node->end) && isset($node->start)) {
    if ($node->start > $node->end) {
      form_set_error('time', t('An event may not end before it starts.'));
    }
  }
}

/**
 * Display a node.
 *
 * This is a hook used by node modules. It allows a module to define a
 * custom method of displaying its nodes, usually by displaying extra
 * information particular to that node type.
 *
 * @param $node
1110
 *   The node to be displayed, as returned by node_load().
1111 1112
 * @param $view_mode
 *   View mode, e.g. 'full', 'teaser', ...
1113 1114 1115
 * @return
 *   $node. The passed $node parameter should be modified as necessary and
 *   returned so it can be properly presented. Nodes are prepared for display
1116 1117
 *   by assembling a structured array, formatted as in the Form API, in
 *   $node->content. As with Form API arrays, the #weight property can be
1118
 *   used to control the relative positions of added elements. After this
1119
 *   hook is invoked, node_view() calls field_attach_view() to add field
1120
 *   views to $node->content, and then invokes hook_node_view() and
1121
 *   hook_node_view_alter(), so if you want to affect the final
1122 1123
 *   view of the node, you might consider implementing one of these hooks
 *   instead.
1124 1125