> For the complete documentation index, see [llms.txt](https://drupal.bermaki.com/drupal-documentation-and-guides/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://drupal.bermaki.com/drupal-documentation-and-guides/backend/hooks.md).

# Hooks

In Drupal, hooks are the main way to interact with the Drupal core.

In Drupal, hooks are the main way to interact with the Drupal core. Hooks are functions that are called at specific times in the Drupal core. For example, when a node is saved, a hook is called. When a user logs in, a hook is called. When a page is loaded, a hook is called. There are many hooks that are called in Drupal and they are all documented in the [Drupal API](https://api.drupal.org/api/drupal/core%21core.api.php/group/hooks/9.1.x).

Hooks are called from the `module_name.module` file or from the `THEME_NAME.theme` file. The `module_name.module` file is where you put all the code that is related to the module. The `THEME_NAME.theme` file is where you put all the code that is related to the theme.

### Templates - hooks that interact with templates

#### Create template suggestions

```php
function THEMENAME_theme_suggestions_page_alter(array &$suggestions, array $variables){
 $suggestions[] = 'page__roads';  //page--roads.html.twig
}
```

#### Add current path as css class

```php
$current_path = \Drupal::service('path.current')->getPath();
$path_alias = \Drupal::service('path_alias.manager')->getAliasByPath($current_path);
$path_alias = ltrim($path_alias, '/');
$variables['attributes']['class'][] = 'path-' . \Drupal\Component\Utility\Html::cleanCssIdentifier($path_alias);
```

#### Get current language

```php
$parameters = \Drupal::routeMatch()->getParameters()->all();
$variables['language'] = \Drupal::languageManager()->getCurrentLanguage();
$variables['language'] = \Drupal::languageManager()->getCurrentLanguage()->getId();
```

#### Get base path

```php
$variables['base_path'] = base_path();
```