headless_cms-1.0.3/modules/headless_cms_notify_nats/src/Plugin/HeadlessNotifyTransport/HeadlessNotifyNatsTransport.php

<?php

declare(strict_types=1);

namespace Drupal\headless_cms_notify_nats\Plugin\HeadlessNotifyTransport;

use Drupal\Core\Form\FormStateInterface;
use Drupal\Core\StringTranslation\TranslatableMarkup;
use Drupal\headless_cms_notify\Attribute\HeadlessNotifyTransport;
use Drupal\headless_cms_notify\NotifyMessage\HeadlessNotifyMessageInterface;
use Drupal\headless_cms_notify\Plugin\HeadlessNotifyTransport\HeadlessNotifyTransportBase;
use Drupal\headless_cms_notify\Plugin\HeadlessNotifyTransportPluginFormInterface;
use Drupal\headless_cms_notify_nats\Event\HeadlessNotifyNatsBeforeSendEvent;
use Drupal\nats\NatsClientManagerInterface;
use Symfony\Component\DependencyInjection\ContainerInterface;
use Symfony\Contracts\EventDispatcher\EventDispatcherInterface;

/**
 * A transport that sends messages via NATS.
 */
#[HeadlessNotifyTransport(
  id: 'nats',
  label: new TranslatableMarkup('NATS'),
)]
class HeadlessNotifyNatsTransport extends HeadlessNotifyTransportBase implements HeadlessNotifyTransportPluginFormInterface {

  public function __construct(
    protected readonly NatsClientManagerInterface $natsClientManager,
    protected readonly EventDispatcherInterface $eventDispatcher,
    array $configuration,
    $plugin_id,
    $plugin_definition,
  ) {
    parent::__construct($configuration, $plugin_id, $plugin_definition);
  }

  /**
   * {@inheritdoc}
   */
  public static function create(ContainerInterface $container, array $configuration, $plugin_id, $plugin_definition) {
    return new static(
      $container->get(NatsClientManagerInterface::class),
      $container->get('event_dispatcher'),
      $configuration,
      $plugin_id,
      $plugin_definition,
    );
  }

  /**
   * {@inheritdoc}
   */
  public function defaultConfiguration() {
    return [
      'nats_client' => '',
      'topic_prefix' => '',
    ];
  }

  /**
   * {@inheritdoc}
   */
  public function buildConfigurationForm(array $form, FormStateInterface $form_state) {
    $form = [];

    $options = [];
    foreach ($this->natsClientManager->getAvailableClients() as $key) {
      $options[$key] = $key;
    }

    $form['nats_client'] = [
      '#type' => 'select',
      '#title' => $this->t('NATS Client'),
      '#description' => $this->t('The NATS client to use for sending messages.'),
      '#default_value' => $this->configuration['nats_client'],
      '#required' => TRUE,
      '#options' => $options,
    ];

    $form['topic_prefix'] = [
      '#type' => 'textfield',
      '#title' => $this->t('Topic Prefix'),
      '#description' => $this->t('The topic prefix to use. Every message sent via NATS is prefixed with this topic. Must not have a trailing dot.'),
      '#default_value' => $this->configuration['topic_prefix'],
      '#required' => TRUE,
    ];

    return $form;
  }

  /**
   * {@inheritdoc}
   */
  public function validateConfigurationForm(array &$form, FormStateInterface $form_state) {
    $topicPrefix = $form_state->getValue('topic_prefix');

    // Make sure the topic prefix only contains letters, numbers, dashes
    // and dots, but does not end with a dot.
    if (!preg_match('/^[a-zA-Z0-9\_\-\.]+[a-zA-Z0-9]+$/', $topicPrefix)) {
      $form_state->setErrorByName('topic_prefix', $this->t('The topic prefix must only contain letters, numbers, dashes and dots. See here: https://docs.nats.io/nats-concepts/subjects#characters-allowed-and-recommended-for-subject-names'));
    }
  }

  /**
   * {@inheritdoc}
   */
  public function submitConfigurationForm(array &$form, FormStateInterface $form_state) {
    $this->configuration['nats_client'] = $form_state->getValue('nats_client');
    $this->configuration['topic_prefix'] = $form_state->getValue('topic_prefix');
  }

  /**
   * {@inheritdoc}
   */
  public function send(HeadlessNotifyMessageInterface $message): void {
    $client = $this->natsClientManager->get($this->configuration['nats_client']);

    $topic = vsprintf('%s.%s', [
      $this->configuration['topic_prefix'],
      $message->getType(),
    ]);

    // Allow modification of topic via event.
    $event = new HeadlessNotifyNatsBeforeSendEvent($topic, $message);
    $this->eventDispatcher->dispatch($event, HeadlessNotifyNatsBeforeSendEvent::EVENT_NAME);

    $client->publish($event->topic, $message->toJson());
  }

}