Snippets

              

                Copy

                  Download

              
              
/**
* Implements hook_form_alter().
*/
function my_module_form_alter(&$form, FormStateInterface $form_state, $form_id) {
    // Lets modify the registration form.
    if ($form_id == 'user_register_form') {
        // Add a new custom text field.
        $form['new_text_field'] = [
            '#type' => 'textfield',
            '#title' => t('Custom Field'),
            '#description' => t('This is a custom field added via form alter.'),
        ];
    }
}
 
            

              

                Copy

                  Download

              
              
/**
* Implements hook_form_alter() to add a custom submit button.
*/
function my_module_form_alter(&$form, FormStateInterface $form_state, $form_id) {
    if ($form_id == 'user_register_form') {
        // Add a custom submit button.
        $form['actions']['custom_submit'] = [
            '#type' => 'submit',
            '#value' => t('Custom Register'),
            '#attributes' => [
                'class' => ['custom-submit-button'],
            ],
            '#submit' => ['my_module_custom_submit_handler'],
        ];
    }
}

function my_module_custom_submit_handler(&$form, $form_state, $form_id) { 
// Custom submit code.
}
            

              

                Copy

                  Download

              
              
/**
* Implements hook_form_alter() to add custom validation.
*/
function my_module_form_alter(&$form, FormStateInterface $form_state, $form_id) {
    if ($form_id == 'user_register_form') {
        // Add custom validation callback.
        $form['#validate'][] = 'my_module_custom_validate';
    }
}
// Now the validation function should be implemented.
function my_module_custom_validate(&$form, FormStateInterface $form_state, $form_id) {
 // Validation code. 
}
            

              

                Copy

                  Download

              
              
/**
* Provides an example AJAX form.
*/
namespace Drupal\my_module\Form;
use Drupal\Core\Form\FormBase;
use Drupal\Core\Form\FormStateInterface;
use Drupal\Core\Ajax\AjaxResponse;
use Drupal\Core\Ajax\HtmlCommand;

class AjaxExampleForm extends FormBase {
   /**
   * {@inheritdoc}
   */
   public function getFormId(): string {
      return 'ajax_example_form';
   }

   /**
   * {@inheritdoc}
   */
   public function buildForm(array $form, FormStateInterface $form_state): array {
      $form['example_text'] = [
         '#type' => 'textfield',
         '#title' => $this->t('Enter text'),
         '#ajax' => [
            'callback' => '::ajaxCallback',
            'wrapper' => 'result-wrapper',
            'event' => 'keyup',
         ],
      ];
      $form['result'] = [
         '#type' => 'container',
         '#attributes' => ['id' => 'result-wrapper'],
      ];
      return $form;
   }

   /**
   * Ajax callback to update the result container.
   */
   public function ajaxCallback(array &$form, FormStateInterface $form_state): AjaxResponse {
      $response = new AjaxResponse();
      $value = $form_state->getValue('example_text');
      $response->addCommand(new HtmlCommand('#result-wrapper', $this->t('You typed: @value', ['@value' => $value])));
      return $response;
   }

   /**
   * {@inheritdoc} (No submission processing required.)
   */
   public function submitForm(array &$form, FormStateInterface $form_state): void { }
}
 
            

              

                Copy

                  Download

              
              
/**
* Implements hook_entity_view_alter() to add cache contexts.
*/
function my_module_entity_view_alter(array &$build, \Drupal\Core\Entity\EntityInterface $entity, \Drupal\Core\Entity\Display\EntityViewDisplayInterface $display, $view_mode) {
   $build['#cache']['contexts'][] = 'user.permissions';
}
 
            

              

                Copy

                  Download

              
              
namespace Drupal\my_module\Service;
use Drupal\Core\Cache\CacheableMetadata;

class MyDataService {
   public function buildData(): array {
      $build = [
         '#markup' => 'Dynamic data output.',
      ];
      $cache_metadata = new CacheableMetadata();
      $cache_metadata->setCacheContexts(['route', 'user.roles']);
      $cache_metadata->applyTo($build);
      return $build;
   }
}
 
            

              

                Copy

                  Download

              
              
/**
* Basic example of using the Cache API to get and set data.
*/
namespace Drupal\my_module;

use Drupal\Core\Cache\Cache;

$cid = 'my_module:unique_cache_id';
$cache = \Drupal::cache()->get($cid);
if ($cache) {
   $data = $cache->data;
} else {
   $data = 'result of expensive processing';
   \Drupal::cache()->set($cid, $data, Cache::PERMANENT);
}
 
            

              

                Copy

                  Download

              
              
namespace Drupal\my_module\Plugin\Block;
use Drupal\Core\Block\BlockBase;

/**
* Provides a 'Hello World' block.
* 
* @Block(
* id = "hello_world_block",
* admin_label = @Translation("Hello World Block")
* )
*/
class HelloWorldBlock extends BlockBase {
   public function build(): array {
      return [
         '#markup' => $this->t('Hello, world!'),
      ];
   }
}
 
            

              

                Copy

                  Download

              
              
/**
* Implements hook_form_alter().
*/
function my_module_form_alter(&$form, FormStateInterface $form_state, $form_id) {
    // Check if the form ID matches.
    if ($form_id == 'user_register_form') {
        // Change form title.
        $form['#title'] = t('Custom User Registration');

        // Modify form attributes.
        $form['#attributes']['class'][] = 'custom-form-class';
        $form['#attributes']['id'] = 'custom_form_id';
    }
}
 
            

              

                Copy

                  Download

              
              
/**
* Provides a 'CachedContentBlock' block.
* @Block annotation is assumed to be defined in the plugin YAML.
*/
use Drupal\Core\Block\BlockBase;

class CachedContentBlock extends BlockBase {
   /**
   * {@inheritdoc}
   */
   public function build(): array {
      $build = [
         '#markup' => $this->t('This content is cached.'),
         '#cache' => [
            'contexts' => ['url.path'],
            'tags' => ['my_module_block'],
            'max-age' => 600,
         ],
      ];
      return $build;
   }
}
 
            

              

                Copy

                  Download

              
              
/**
* Lists the configurable fields for a bundle.
*/
drush field:info node article;
 
            

              

                Copy

                  Download

              
              
/**
* Displays the directory path for modules, themes or other items.
*/
drush drupal:directory modules/contrib;
// Alias: dr:dir
// Output: /var/www/html/modules/contrib
 
            

              

                Copy

                  Download

              
              
/**
* Displays a summary of the status of the Drupal and Drush environment.
*/
drush core:status;

 
            

              

                Copy

                  Download

              
              
/**
* Displays the Drupal site requirements report.
*/
drush core:requirements
 
            

              

                Copy

                  Download

              
              
/**
* Check for updates in translations.
*/
drush locale:check;
            

              

                Copy

                  Download

              
              
/**
* Clears the status of translation updates.
*/
drush locale:clear-status;
 
            

              

                Copy

                  Download

              
              
namespace Drupal\my_module\Plugin\Block;
use Drupal\Core\Block\BlockBase;
use Drupal\Core\Form\FormStateInterface;
/**
* Provides a configurable block.
*
* @Block(
* id = "configurable_block",
* admin_label = @Translation("Configurable Block")
* )
*/

class ConfigurableBlock extends BlockBase {
   /**
    * {@inheritdoc}
    */
   public function build(): array {
      $config = $this->getConfiguration();
      return [
         '#markup' => $this->t('Configurable value: @value', ['@value' => $config['block_value'] ?? 'Default']),
      ];
   }

   /**
    * {@inheritdoc}
    */
   public function blockForm(array $form, FormStateInterface $form_state): array {
      $form = parent::blockForm($form, $form_state);
      $config = $this->getConfiguration();
      $form['block_value'] = [
         '#type' => 'textfield',
         '#title' => $this->t('Block Value'),
         '#default_value' => $config['block_value'] ?? '',
      ];
      return $form;
   }

   /**
    * {@inheritdoc}
    */
   public function blockSubmit(array &$form, FormStateInterface $form_state): void {
      $this->setConfigurationValue('block_value', $form_state->getValue('block_value'));
   }
}
 
            

              

                Copy

                  Download

              
              
/**
* Create a new user with a password.
*/
drush user:create username --mail=user@example.com --password=password;
 
            

              

                Copy

                  Download

              
              
/**
* Creates a new field for an entity bundle.
*/
drush field:create node article field_tags taxonomy_term;
 
            

              

                Copy

                  Download

              
              
/**
* Defines a custom Ajax command.
*/
namespace Drupal\my_module\Ajax;
use Drupal\Core\Ajax\CommandInterface;

class CustomCommand implements CommandInterface {
   /**
   * The message to display.
   */
   protected string $message;

   /**
   * Constructs a CustomCommand object.
   */
   public function __construct(string $message) {
      $this->$message = $message;
   }

   /**
   * {@inheritdoc}
   */
   public function render(): array {
      return [
         'command' => 'customCommand',
         'message' => $this->$message,
      ];
   }
}
 
            

              

                Copy

                  Download

              
              
/**
* Retrieve data from a custom cache bin or generate and store it.
*/
$cid = 'my_module:custom_item';
$cache_bin = \Drupal::service('cache.my_module_bin');
if ($item = $cache_bin->get($cid))) {
   $data = $item->data;
} else {
   $data = 'Expensive data calculation';
   $cache_bin->set($cid, $data, Cache::PERMANENT);
}
 
            

              

                Copy

                  Download

              
              
namespace Drupal\my_module\Cache\Context;

use Drupal\Core\Cache\Context\CacheContextInterface;
use Drupal\Core\Cache\CacheableMetadata;
/**
* Provides a custom cache context based on the current hour.
*
* @CacheContext(
* id = "my_custom_time",
* label = @Translation("Custom Time Cache Context")
* )
*/

class MyCustomTimeCacheContext implements CacheContextInterface {
   public function getContext(): string {
      return date('H');
   }

   public function getCacheableMetadata(): CacheableMetadata {
      return new CacheableMetadata();
   }
}
 
            

              

                Copy

                  Download

              
              
/**
* Service class for caching data using dependency injection.
*/

use Drupal\Core\Cache\CacheBackendInterface;

class MyCacheService {
   /**
   * The cache backend service.
   */
   protected CacheBackendInterface $cacheBackend;

   /**
   * Constructs a MyCacheService object.
   */
   public function __construct(CacheBackendInterface $cache_backend) {
      $this->$cacheBackend = $cache_backend;
   }

   public function getData(string $cid): ?string {
      $cache = $this->$cacheBackend->get($cid);
      return $cache ? $cache->data : NULL;
   }

   public function setData(string $cid, string $data, int $expire = CacheBackendInterface::CACHE_PERMANENT): void {
      $this->$cacheBackend->set($cid, $data, $expire);
   }
}
 
            

              

                Copy

                  Download

              
              
/**
* Deletes a record from a custom table.
*/
function my_module_delete_data() {
    \Drupal::database()->delete('custom_table')
        ->condition('id', 10, '=')
        ->execute();
}
 
            

              

                Copy

                  Download

              
              
/**
* Creates an archive dump that includes code, files and database.
*/
drush archive:dump --destination=/path/to/archive.tar.gz --overwrite --exclude-code-paths=web/sites/default/settings.php
// Alias: N/A
// Output: Archive created at /path/to/archive.tar.gz
 
            

              

                Copy

                  Download

              
              
/**
* Load More Form using AJAX.
*/
namespace Drupal\my_module\Form;

use Drupal\Core\Form\FormBase;
use Drupal\Core\Form\FormStateInterface;
use Drupal\Core\Ajax\AjaxResponse;
use Drupal\Core\Ajax\AppendCommand;

class LoadMoreForm extends FormBase {

   /**
   * {@inheritdoc}
   */
   public function getFormId(): string {
      return 'load_more_form';
   }

   /**
   * {@inheritdoc}
   */
   public function buildForm(array $form, FormStateInterface $form_state): array {
      $items = $form_state->get('items') ?? ['Item 1', 'Item 2', 'Item 3'];
      $form_state->set('items', $items);

      $form['items_container'] = [
         '#type' => 'container',
         '#attributes' => ['id' => 'items-container'],
      ];

      foreach ($items as $item) {
         $form['items_container'][] = [
            '#markup' => '<p>' . $item . '</p>',
         ];
      }

      $form['load_more'] = [
         '#type' => 'submit',
         '#value' => $this->t('Load more'),
         '#ajax' => [
            'callback' => '::loadMoreAjaxCallback',
            'wrapper' => 'items-container',
            'effect' => 'fade',
         ],
      ];

      return $form;
   }

   /**
   * AJAX callback to append new items.
   */
   public function loadMoreAjaxCallback(array &$form, FormStateInterface $form_state): AjaxResponse {
      $response = new AjaxResponse();
      $items = $form_state->get('items') ?? [];

      $count = count($items) + 1;
      $new_items = [
         ['#markup' => '<p>Item ' . $count . '</p>'],
         ['#markup' => '<p>Item ' . ($count + 1) . '</p>'],
      ];

      $items[] = 'Item ' . $count;
      $items[] = 'Item ' . ($count + 1);
      $form_state->set('items', $items);
      $response->addCommand(new AppendCommand('#items-container', $new_items));

      return $response;
   }

   /**
   * {@inheritdoc} (No normal submit processing required.)
   */
   public function submitForm(array &$form, FormStateInterface $form_state): void {}
}
 
            

              

                Copy

                  Download

              
              
/**
* Export translations to a .po file.
*/
drush locale:export fr --file=translations.fr.po;
 
            

              

                Copy

                  Download

              
              
/**
* Generates code base for different elements (modules, plugins, etc.).
*/
drush generate;
 
            

              

                Copy

                  Download

              
              
/**
* Shows whether the maintenance mode is activated or not.
*/
drush maint:get;
Alias: N/A
Output: Maintenance mode is OFF.
 
            

              

                Copy

                  Download

              
              
/**
* Import translations from a .po file.
*/
drush locale:import fr translations.fr.po;
 
            

              

                Copy

                  Download

              
              
/**
* Inserts a record into a custom table.
*/
function my_module_insert_data() {
    \Drupal::database()->insert('custom_table')
        ->fields([
            'name' => 'Sample Name',
            'status' => 1,
        ])
        ->execute();
}
 
            

              

                Copy

                  Download

              
              
/**
* Enable a specific module.
*/
drush en module_name -y;
 
/**
* Uninstall a specific module.
*/
drush pm:uninstall module_name -y;
 
            

              

                Copy

                  Download

              
              
/**
* Invalidate cache entries tagged with 'my_module_tag'.
*/
\Drupal::cache()->invalidateTags(['my_module_tag']);
 
            

              

                Copy

                  Download

              
              
/**
* Displays a complete list of Drush commands.
*/
drush list;
 
            

              

                Copy

                  Download

              
              
/**
*  Lists the base fields of an entity.
*/
drush field:base-info node;
// Alias: N/A
// Example output:
// ------------------------------- ---------- ------------------ ------------- 
// Field name Required Field type Cardinality 
// ------------------------------- ---------- ------------------ ------------- 
// nid integer 1 
// uuid uuid 1 
// vid integer 1 
// langcode language 1 
// type ✔ entity_reference 1 
// revision_timestamp created 1 
// revision_uid entity_reference 1 
// revision_log string_long 1 
// status boolean 1 
// uid entity_reference 1 
// title ✔ string 1 
// created created 1 
// changed changed 1 
// promote boolean 1 
// sticky boolean 1 
// default_langcode boolean 1 
// revision_default boolean 1 
// revision_translation_affected boolean 1 
// metatag metatag_computed -1 
// path path 1 
// menu_link entity_reference 1 
// content_translation_source language 1 
// content_translation_outdated boolean 1 
// ------------------------------- ---------- ------------------ ------------- 
 
            

              

                Copy

                  Download

              
              
/**
* Implements hook_form_alter() to modify existing form fields.
*/
function my_module_form_alter(&$form, FormStateInterface $form_state, $form_id) {
    if ($form_id == 'user_register_form') {
        if (isset($form['mail'])) {
            // Change the title of the 'mail' field.
            $form['mail']['#title'] = t('Custom Email Address');
            // Change the value of the 'mail' field.
            $form['mail']['#value'] = test@example.com;
        }
    }
}
 
            

              

                Copy

                  Download

              
              
namespace Drupal\my_module\Controller;
use Drupal\Core\Controller\ControllerBase;
use Drupal\Core\Ajax\CacheableJsonResponse;
use Drupal\Core\Cache\CacheableMetadata;
use Symfony\Component\DependencyInjection\ContainerInterface;
 
/**
* Returns a JSON response with overridden cache metadata.
*/
class OverrideCacheController extends ControllerBase {
   /**
    * {@inheritdoc}
    */
   public static function create(ContainerInterface $container) {
      return new static();
   }

   public function overrideCache(): CacheableJsonResponse {
      $data = [
         'content' => $this->t('Response with overridden cache metadata.'),
      ];
      $response = new CacheableJsonResponse($data);
      $cache_metadata = new CacheableMetadata();
      $cache_metadata->setCacheTags(['override_tag']);
      $cache_metadata->setCacheContexts(['user.uid']);
      $cache_metadata->setCacheMaxAge(0); // Non-cacheable
      $response->addCacheableDependency($cache_metadata);
      return $response;
   }
}
 
            

              

                Copy

                  Download

              
              
/**
* Creates an overwrite of a base field for a bundle.
*/
drush field:base-override-create node article field_example;
 
            

              

                Copy

                  Download

              
              
/**
* Executes post-deployment commands.
*/
drush deploy;
 
            

              

                Copy

                  Download

              
              
/**
* Removes a field from a bundle.
*/
drush field:delete node article field_tags;
 
            

              

                Copy

                  Download

              
              
/**
* Removes content entities from a given bundle.
*/
drush entity:delete node --bundle=article;
 
            

              

                Copy

                  Download

              
              
$build = [
   '#markup' => 'Hello, world!',
   '#cache' => [
      'contexts' => ['user.roles'],
   ],
];
return $build;
 
            

              

                Copy

                  Download

              
              
/**
* Render array with Cache API metadata.
*/
$form = [];
$form['content'] = [
   '#markup' => 'Hello World',
   '#cache' => [
      'contexts' => ['user.permissions'],
      'tags' => ['node_list'],
      'max-age' => 3600,
   ],
];
return $form;
 
            

              

                Copy

                  Download

              
              
namespace Drupal\my_module\Controller;
use Drupal\Core\Controller\ControllerBase;
use Drupal\Core\Cache\CacheableMetadata;
use Drupal\Core\Ajax\CacheableJsonResponse;

class MyController extends ControllerBase {
   /**
    * Returns a cacheable JSON response with custom metadata.
    */
   public function jsonContent(): CacheableResponseInterface {
      $data = [
         'message' => $this->t('Hello, cacheable JSON response!'),
      ];
      $cache_metadata = new CacheableMetadata();
      $cache_metadata->setCacheTags(['my_module_tag']);
      $cache_metadata->setCacheContexts(['url.path', 'user.roles']);
      $cache_metadata->setCacheMaxAge(3600);

      $response = new \Drupal\Core\Ajax\CacheableJsonResponse($data);
      $response->addCacheableDependency($cache_metadata);

      return $response;
   }
}
 
            

              

                Copy

                  Download

              
              
/**
* Saves a configuration value directly.
*/
drush config:set system.site name "New Site Name";
 
            

              

                Copy

                  Download

              
              
/**
* Fetches data from a custom table.
*/
function my_module_get_data() {
    $query = \Drupal::database()->select('custom_table', 'ct');
    $query->fields('ct', ['id', 'name', 'status']);

    $result = $query->execute()->fetchAll();

    return $result;
}
 
            

              

                Copy

                  Download

              
              
/**
* Updates data in a custom table.
*/
function my_module_update_data() {
    \Drupal::database()->update('custom_table')
        ->fields([
            'status' => 0,
        ])
        ->condition('id', 5, '=')
        ->execute();
}
 
            

              

                Copy

                  Download

              
              
/**
* Updates the translations installed on the system.
*/
drush locale:update;
            

              

                Copy

                  Download

              
              
/**
* Implements hook_form_alter() to add conditional states.
*/
function my_module_form_alter($form, FormStateInterface $form_state, $form_id) {
    if ($form_id == 'custom_form_id') {
        // Add a checkbox to control the visibility of another field.
        $form['show_additional_info'] = [
            '#type' => 'checkbox',
            '#title' => t('Show additional information'),
        ];

        // Add a textfield that will only be shown when the checkbox is checked.
        $form['additional_info'] = [
            '#type' => 'textfield',
            '#title' => t('Additional Information'),
            '#states' => [
                'visible' => [
                    ':input[name="show_additional_info"]' => [
                        'checked' => TRUE,
                    ],
                ],
            ],
        ];
    }
}
 
            

              

                Copy

                  Download

              
              
/**
* Implements hook_form_alter() to add AJAX functionality.
*/
function my_module_form_alter($form, FormStateInterface $form_state, $form_id) {
    if ($form_id == 'custom_form_id') {
        // Add a select element with AJAX properties.
        $form['select_field'] = [
            '#type' => 'select',
            '#title' => t('Choose an option'),
            '#options' => [
                'option_1' => 'Option 1',
                'option_2' => 'Option 2',
            ],
            '#ajax' => [
                'callback' => 'my_module_ajax_callback',
                'wrapper' => 'ajax-wrapper',
            ],
        ];

        // Add a container to be updated via AJAX.
        $form['ajax_container'] = [
            '#type' => 'container',
            '#attributes' => [
                'id' => 'ajax-wrapper',
            ],
        '#markup' => t('Select an option to update this content.'),
        ];
    }
}
 
/**
* AJAX callback function.
*/
function my_module_ajax_callback(array $form, FormStateInterface $form_state) {
    // Update the content of the AJAX container based on the selected value.
    $selected_value = $form_state->getValue('select_field');
    if ($selected_value == 'option_1') {
        $form['ajax_container']['#markup'] = t('You selected Option 1.');
    } else if ($selected_value == 'option_2') {
        $form['ajax_container']['#markup'] = t('You selected Option 2.');
    }

    // Return the updated container.
    return $form['ajax_container'];
}
 
            

              

                Copy

                  Download

              
              
/**
* Displays documentation on a specific Drush topic.
*/
drush core:topic;