1 system.api.php hook_library_info()

Registers JavaScript/CSS libraries associated with a module.

Modules implementing this return an array of arrays. The key to each sub-array is the machine readable name of the library. Each library may contain the following items:

  • 'title': The human readable name of the library.
  • 'website': The URL of the library's web site.
  • 'version': A string specifying the version of the library; intentionally not a float because a version like "1.2.3" is not a valid float. Use PHP's version_compare() to compare different versions.
  • 'js': An array of JavaScript elements; each element's key is used as $data argument, each element's value is used as $options array for backdrop_add_js(). To add library-specific (not module-specific) JavaScript settings, the key may be skipped, the value must specify 'type' => 'setting', and the actual settings must be contained in a 'data' element of the value.
  • 'css': Like 'js', an array of CSS elements passed to backdrop_add_css().
  • 'dependencies': An array of libraries that are required for a library. Each element is an array listing the module and name of another library. Note that all dependencies for each dependent library will also be added when this library is added.

Registered information for a library should contain re-usable data only. Module- or implementation-specific data and integration logic should be added separately.

Return value

An array defining libraries associated with a module.:

See also




Related topics


core/modules/system/system.api.php, line 338
Hooks provided by Backdrop core and the System module.


function hook_library_info() {
  // Library One.
  $libraries['library-1'] = array(
    'title' => 'Library One',
    'website' => 'http://example.com/library-1',
    'version' => '1.2',
    'js' => array(
      backdrop_get_path('module', 'my_module') . '/library-1.js' => array(),
    'css' => array(
      backdrop_get_path('module', 'my_module') . '/library-2.css' => array(
        'type' => 'file',
        'media' => 'screen',
  // Library Two.
  $libraries['library-2'] = array(
    'title' => 'Library Two',
    'website' => 'http://example.com/library-2',
    'version' => '3.1-beta1',
    'js' => array(
      // JavaScript settings may use the 'data' key.
        'type' => 'setting',
        'data' => array('library2' => TRUE),
    'dependencies' => array(
      // Require jQuery UI core by System module.
      array('system', 'ui'),
      // Require our other library.
      array('my_module', 'library-1'),
      // Require another library.
      array('other_module', 'library-3'),
  return $libraries;