GraphQL: Added liveblogPosts to NodeLiveblog

src/Plugin/GraphQL/Fields/LiveblogPosts.php

@@ -0,0 +1,72 @@
+<?php
+namespace Drupal\liveblog\Plugin\GraphQL\Fields;
+
+use Drupal\Core\DependencyInjection\DependencySerializationTrait;
+use Drupal\Core\Entity\EntityTypeManagerInterface;
+use Drupal\Core\Plugin\ContainerFactoryPluginInterface;
+use Drupal\graphql\Annotation\GraphQLField;
+use Drupal\graphql\Plugin\GraphQL\Fields\FieldPluginBase;
+use Drupal\node\Entity\Node;
+use Symfony\Component\DependencyInjection\ContainerInterface;
+use Youshido\GraphQL\Execution\ResolveInfo;
+
+/**
+ * Class LiveblogPosts
+ *
+ * @GraphQLField(
+ *   id = "liveblog_posts",
+ *   type = "LiveblogPost",
+ *   name = "liveblogPosts",
+ *   nullable = true,
+ *   multi = true,
+ *   parents = {"NodeLiveblog"}
+ * )
+ */
+class LiveblogPosts extends FieldPluginBase implements ContainerFactoryPluginInterface {
+  use DependencySerializationTrait;
+
+  /**
+   * The entity type manager.
+   *
+   * @var \Drupal\Core\Entity\EntityTypeManagerInterface
+   */
+  protected $entityTypeManager;
+
+  /**
+   * {@inheritdoc}
+   */
+  public function __construct(array $configuration, $pluginId, $pluginDefinition, EntityTypeManagerInterface $entityTypeManager) {
+    $this->entityTypeManager = $entityTypeManager;
+    parent::__construct($configuration, $pluginId, $pluginDefinition);
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public static function create(ContainerInterface $container, array $configuration, $pluginId, $pluginDefinition) {
+    return new static(
+      $configuration,
+      $pluginId,
+      $pluginDefinition,
+      $container->get('entity_type.manager')
+    );
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  protected function resolveValues($value, array $args, ResolveInfo $info) {
+    if ($value instanceof Node && $value->bundle() == 'liveblog') {
+      $storage = $this->entityTypeManager->getStorage('liveblog_post');
+
+      $liveblog_posts = $storage->loadByProperties([
+        'liveblog' => $value->id(),
+      ]);
+
+      foreach ($liveblog_posts as $post) {
+        yield $post;
+      }
+    }
+  }
+
+}