PER-10: Added new search index field for image discovery

config/schema/search_api.processor.schema.yml

@@ -0,0 +1,7 @@
+search_api.property_configuration.dgi_image_discovery:
+  type: mapping
+  label: DGI Image Discovery
+  mapping:
+    image_style:
+      type: string
+      label: 'The image style to be used to create image url'

src/Plugin/search_api/processor/DgiImageDiscovery.php

@@ -0,0 +1,128 @@
+<?php
+
+namespace Drupal\dgi_image_discovery\Plugin\search_api\processor;
+
+use Drupal\Core\Entity\EntityTypeManagerInterface;
+use Drupal\Core\Plugin\ContainerFactoryPluginInterface;
+use Drupal\dgi_image_discovery\ImageDiscoveryInterface;
+use Drupal\dgi_image_discovery\Plugin\search_api\processor\Property\DgiImageDiscoveryProperty;
+use Drupal\node\NodeInterface;
+use Drupal\search_api\Datasource\DatasourceInterface;
+use Drupal\search_api\Item\ItemInterface;
+use Drupal\search_api\Processor\ProcessorPluginBase;
+use Symfony\Component\DependencyInjection\ContainerInterface;
+
+/**
+ * Get the styled image url for the islandora node.
+ *
+ * @SearchApiProcessor(
+ *   id = "dgi_image_discovery",
+ *   label = @Translation("DGI Image Discovery"),
+ *   description = @Translation("Get the styled image url for the islandora node."),
+ *   stages = {
+ *     "add_properties" = 0,
+ *   },
+ *   locked = true,
+ *   hidden = true,
+ * )
+ */
+class DgiImageDiscovery extends ProcessorPluginBase implements ContainerFactoryPluginInterface {
+
+  /**
+   * The entity type manager service.
+   *
+   * @var \Drupal\Core\Entity\EntityTypeManagerInterface
+   */
+  protected $entityTypeManager;
+
+  /**
+   * The DGI Image Discovery service.
+   *
+   * @var \Drupal\dgi_image_discovery\ImageDiscoveryInterface
+   */
+  protected $imageDiscovery;
+
+  /**
+   * {@inheritdoc}
+   */
+  public function __construct(
+    array $configuration,
+    $plugin_id,
+    $plugin_definition,
+    ImageDiscoveryInterface $image_discovery,
+    EntityTypeManagerInterface $entity_type_manager
+  ) {
+    parent::__construct($configuration, $plugin_id, $plugin_definition);
+
+    $this->imageDiscovery = $image_discovery;
+    $this->entityTypeManager = $entity_type_manager;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public static function create(ContainerInterface $container, array $configuration, $plugin_id, $plugin_definition) {
+    return new static(
+      $configuration,
+      $plugin_id,
+      $plugin_definition,
+      $container->get('dgi_image_discovery.service'),
+      $container->get('entity_type.manager')
+    );
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function getPropertyDefinitions(DatasourceInterface $datasource = NULL) {
+    $properties = [];
+
+    if (!$datasource) {
+      $definition = [
+        'label' => $this->t('DGI Image Discovery'),
+        'description' => $this->t('Styled Image Url which can then be passed to the image src.'),
+        'type' => 'string',
+        'is_list' => FALSE,
+        'processor_id' => $this->getPluginId(),
+      ];
+      $properties['dgi_image_discovery'] = new DgiImageDiscoveryProperty($definition);
+    }
+
+    return $properties;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function addFieldValues(ItemInterface $item) {
+    $entity = $item->getOriginalObject()->getValue();
+    $value = NULL;
+
+    // Get the image discovery URL.
+    if (!$entity->isNew() && $entity instanceof NodeInterface) {
+      $event = $this->imageDiscovery->getImage($entity);
+      $media = $event->getMedia();
+      if (empty($media)) {
+        return;
+      }
+
+      $media_source = $media->getSource();
+      $file_id = $media_source->getSourceFieldValue($media);
+      $image = $this->entityTypeManager->getStorage('file')->load($file_id);
+      if (empty($image)) {
+        return;
+      }
+
+      $fields = $item->getFields(FALSE);
+      $fields = $this->getFieldsHelper()->filterForPropertyPath($fields, NULL, 'dgi_image_discovery');
+      foreach ($fields as $field) {
+        $config = $field->getConfiguration();
+        $image_style = $config['image_style'];
+        $value = $this->entityTypeManager->getStorage('image_style')->load($image_style)
+          ->buildUrl($image->getFileUri());
+        $field->addValue($value);
+      }
+    }
+  }
+
+}

src/Plugin/search_api/processor/Property/DgiImageDiscoveryProperty.php

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+<?php
+
+namespace Drupal\dgi_image_discovery\Plugin\search_api\processor\Property;
+
+use Drupal\Core\Form\FormStateInterface;
+use Drupal\Core\StringTranslation\StringTranslationTrait;
+use Drupal\search_api\Item\FieldInterface;
+use Drupal\search_api\Processor\ConfigurablePropertyBase;
+
+/**
+ * Defines a "DGI Image Discovery" property.
+ */
+class DgiImageDiscoveryProperty extends ConfigurablePropertyBase {
+
+  use StringTranslationTrait;
+
+  /**
+   * {@inheritdoc}
+   */
+  public function defaultConfiguration() {
+    return [
+      'image_style' => 'solr_grid_thumbnail',
+    ];
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function buildConfigurationForm(FieldInterface $field, array $form, FormStateInterface $form_state) {
+    $configuration = $field->getConfiguration() + $this->defaultConfiguration();
+
+    $form['image_style'] = [
+      '#type' => 'select',
+      '#options' => image_style_options(FALSE),
+      '#title' => $this->t('Image Style'),
+      '#description' => $this->t('Select the image style that should be applied to derive the DGI Image Discovery image url.'),
+      '#default_value' => $configuration['image_style'],
+    ];
+
+    return $form;
+  }
+
+}