function node_access

Determines whether the current user may perform the operation on the node.

Parameters

$op: The operation to be performed on the node. Possible values are:

  • "view"
  • "update"
  • "delete"
  • "create"

$node: The node object on which the operation is to be performed, or node type (e.g. 'forum') for "create" operation.

$account: Optional, a user object representing the user for whom the operation is to be performed. Determines access for a user other than the current user.

Return value

TRUE if the operation may be performed, FALSE otherwise.

Related topics

20 calls to node_access()
book_block_view in modules/book/book.module
Implements hook_block_view().
book_export in modules/book/book.pages.inc
Menu callback; Generates representations of a book page and its children.
book_node_view_link in modules/book/book.module
Adds relevant book links to the node's links.
comment_file_download_access in modules/comment/comment.module
Implements hook_file_download_access().
forum_menu_local_tasks_alter in modules/forum/forum.module
Implements hook_menu_local_tasks_alter().

... See full list

26 string references to 'node_access'
book_block_view in modules/book/book.module
Implements hook_block_view().
book_get_books in modules/book/book.module
Returns an array of all books.
comment_admin_overview in modules/comment/comment.admin.inc
Form builder for the comment overview administration form.
comment_get_recent in modules/comment/comment.module
Find the most recent comments that are available to the current user.
comment_menu in modules/comment/comment.module
Implements hook_menu().

... See full list

File

modules/node/node.module, line 2990

Code

function node_access($op, $node, $account = NULL) {
    $rights =& drupal_static(__FUNCTION__, array());
    if (!$node || !in_array($op, array(
        'view',
        'update',
        'delete',
        'create',
    ), TRUE)) {
        // If there was no node to check against, or the $op was not one of the
        // supported ones, we return access denied.
        return FALSE;
    }
    // If no user object is supplied, the access check is for the current user.
    if (empty($account)) {
        $account = $GLOBALS['user'];
    }
    // $node may be either an object or a node type. Since node types cannot be
    // an integer, use either nid or type as the static cache id.
    $cid = is_object($node) ? $node->nid : $node;
    // If we've already checked access for this node, user and op, return from
    // cache.
    if (isset($rights[$account->uid][$cid][$op])) {
        return $rights[$account->uid][$cid][$op];
    }
    if (user_access('bypass node access', $account)) {
        $rights[$account->uid][$cid][$op] = TRUE;
        return TRUE;
    }
    if (!user_access('access content', $account)) {
        $rights[$account->uid][$cid][$op] = FALSE;
        return FALSE;
    }
    // We grant access to the node if both of the following conditions are met:
    // - No modules say to deny access.
    // - At least one module says to grant access.
    // If no module specified either allow or deny, we fall back to the
    // node_access table.
    $access = module_invoke_all('node_access', $node, $op, $account);
    if (in_array(NODE_ACCESS_DENY, $access, TRUE)) {
        $rights[$account->uid][$cid][$op] = FALSE;
        return FALSE;
    }
    elseif (in_array(NODE_ACCESS_ALLOW, $access, TRUE)) {
        $rights[$account->uid][$cid][$op] = TRUE;
        return TRUE;
    }
    // Check if authors can view their own unpublished nodes.
    if ($op == 'view' && !$node->status && user_access('view own unpublished content', $account) && $account->uid == $node->uid && $account->uid != 0) {
        $rights[$account->uid][$cid][$op] = TRUE;
        return TRUE;
    }
    // If the module did not override the access rights, use those set in the
    // node_access table.
    if ($op != 'create' && $node->nid) {
        if (module_implements('node_grants')) {
            $query = db_select('node_access');
            $query->addExpression('1');
            $query->condition('grant_' . $op, 1, '>=');
            $nids = db_or()->condition('nid', $node->nid);
            if ($node->status) {
                $nids->condition('nid', 0);
            }
            $query->condition($nids);
            $query->range(0, 1);
            $grants = node_add_node_grants_to_query(node_access_grants($op, $account));
            if (count($grants) > 0) {
                $query->condition($grants);
            }
            $result = (bool) $query->execute()
                ->fetchField();
            $rights[$account->uid][$cid][$op] = $result;
            return $result;
        }
        elseif (is_object($node) && $op == 'view' && $node->status) {
            // If no modules implement hook_node_grants(), the default behavior is to
            // allow all users to view published nodes, so reflect that here.
            $rights[$account->uid][$cid][$op] = TRUE;
            return TRUE;
        }
    }
    return FALSE;
}

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