useful_drupal

A general list and cheatsheet of useful Drupal programming structures and "gotchas."

Querying

Get all query parameters

\Drupal::request()->query->all()

Get single query parameter

\Drupal::request()->query->get('paramKey')

Entities

Users

Load User By Id

\Drupal\user\Entity\User::load(**$id**)

Create User

\Drupal\user\Entity\User::create()

Get Current User AccountInterface

\Drupal::currentUser()

Get user by custom field

 $user_lookup = \Drupal::entityQuery('user')
      ->condition('field_user_first_name', 'Foo');
    $user_nids = $user_lookup->execute();

Check if user is authenticated or annonymous

\Drupal::currentUser()->isAutheticated() \Drupal::currentUser()->isAnnonymous()

Get Full User object

$current_user_entity = User::load(\Drupal::currentUser()->id());

Nodes

Load a node

\Drupal::entityTypeManager()->getStorage('node')->load($nid);

Get Current Node

\Drupal::routeMatch()->getParameter('node');

Get Node By Field

$nodes = \Drupal::entityTypeManager()
  ->getStorage('node')
  ->loadByProperties(array('field_machine_name' => $field_machine_name));

Get All Entity References (returns array)

$referenced_entities = $node->get('field_entity_ref')
  ->referencedEntities();

Get Referenced Object (Node, as an example)

$referencedEntity = $association
  ->get('field_entity_ref')
  ->first()
  ->get('entity')
  ->getTarget()
  ->getValue();

Delete All Nodes By Type

$ drush genc 0 —kill –types=article 

Paragraphs

Load Paragraph

\Drupal::entityManager()->getStorage('paragraph')->load($pid)

Create multiple new paragraphs

$multiParagraph1 = Paragraph::create([
  'type' => 'paragraph_machine_name',
  'field_machine_name' => 'Field value',
]);
$multiParagraph2 = Paragraph::create([
  'type' => 'paragraph_machine_name',
  'field_machine_name' => 'Field value',
]);
$multiParagraph1->save();
$multiParagraph2->save();

Add multiple Paragraphs to an entity ref field

$node->paragraph_entity_ref_field[] = [
  'target_id' => $multiParagraph1->id(),
  'target_revision_id' => $multiParagraph1->getRevisionId(),
];

$node->paragraph_entity_ref_field[] = [
  'target_id' => $multiParagraph2->id(),
  'target_revision_id' => $multiParagraph2->getRevisionId(),
];

Blocks

Create block programmatically

use Drupal\Core\Block\BlockBase;

class BlockClassName extends BlockBase {
    public function build() {
        // Code here...

        return array(
            '#type' => 'type',
            '#markup' => 'markup'
        );
    }
}

Redirects

return $this->redirect('<front>');

Events

Kernel Events

KernelEvents::CONTROLLER; // The CONTROLLER event occurs once a controller was found for handling a request.
KernelEvents::EXCEPTION; // The EXCEPTION event occurs when an uncaught exception appears.
KernelEvents::FINISH_REQUEST; //The FINISH_REQUEST event occurs when a response was generated for a request.
KernelEvents::REQUEST; // The REQUEST event occurs at the very beginning of request dispatching.
KernelEvents::RESPONSE; // The RESPONSE event occurs once a response was created for replying to a request.
KernelEvents::TERMINATE; // The TERMINATE event occurs once a response was sent.
KernelEvents::VIEW; // The VIEW event occurs when the return value of a controller is not a Response instance.

Queues

Run a queue from drush.

Accepts 1 argument, queue_name, and 1 option, --time-limit (in seconds)

drush -l environment queue-run queue_name --time-limit=seconds

Example:

drush -l local queue-run update_users --time-limit=600

Config

Run 'install' config on an already-installed module

$ drush cim -y --partial --source=modules/_custom/my_module/config/install/

alternatively,

Navigate to the devel tab on the admin site, then click the 'Execute PHP' tab.

$config_installer = \Drupal::service('config.installer');
$config_installer->installDefaultConfig('module', 'mymodule_name');

Gotchas

View Templates

All views templates can be overridden with a variety of names, using the view, the display ID of the view, the display type of the view, or some combination thereof.

For each view, there will be a minimum of two templates used. The first is used for all views: views-view.html.twig.

The second template is determined by the style selected for the view. Note that certain aspects of the view can also change which style is used; for example, arguments which provide a summary view might change the style to one of the special summary styles.

The default style for all views is views-view-unformatted.html.twig.

Many styles will then farm out the actual display of each row to a row style; the default row style is views-view-fields.html.twig.

Here is an example of all the templates that will be tried in the following case:

View, named foobar. Style: unformatted. Row style: Fields. Display: Page.

views-view--foobar--page.html.twig
views-view--page.html.twig
views-view--foobar.html.twig
views-view.html.twig
views-view-unformatted--foobar--page.html.twig
views-view-unformatted--page.html.twig
views-view-unformatted--foobar.html.twig
views-view-unformatted.html.twig
views-view-fields--foobar--page.html.twig
views-view-fields--page.html.twig
views-view-fields--foobar.html.twig
views-view-fields.html.twig

Important! When adding a new template to your theme, be sure to flush the theme registry cache!

More Information

https://api.drupal.org/api/drupal/core%21modules%21views%21views.theme.inc/group/views_templates/8.2.x

Return Values

getValue() returns an array. ->value returns field value.

Entity Field Names

$entity->get('field_name')->getValue(); is synonymous with $entity->field_name->getValue();.

Check Page Status Code

$status = \Drupal::requestStack()->getCurrentRequest()->attributes->get('exception');
if ($status && $status->getStatusCode() == 404){
  //...
}