Drupal 8.0.0 beta 12. More info: https://www.drupal.org/node/2514176

core/modules/aggregator/src/AggregatorFeedViewsData.php

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+<?php
+
+/**
+ * @file
+ * Contains \Drupal\aggregator\AggregatorFeedViewsData.
+ */
+
+namespace Drupal\aggregator;
+
+use Drupal\views\EntityViewsData;
+
+/**
+ * Provides the views data for the aggregator feed entity type.
+ */
+class AggregatorFeedViewsData extends EntityViewsData {
+
+  /**
+   * {@inheritdoc}
+   */
+  public function getViewsData() {
+    $data = parent::getViewsData();
+
+    $data['aggregator_feed']['table']['join'] = array(
+      'aggregator_item' => array(
+        'left_field' => 'fid',
+        'field' => 'fid',
+      ),
+    );
+
+    $data['aggregator_feed']['fid']['help'] = $this->t('The unique ID of the aggregator feed.');
+    $data['aggregator_feed']['fid']['argument']['id'] = 'aggregator_fid';
+    $data['aggregator_feed']['fid']['argument']['name field'] = 'title';
+    $data['aggregator_feed']['fid']['argument']['numeric'] = TRUE;
+
+    $data['aggregator_feed']['fid']['filter']['id'] = 'numeric';
+
+    $data['aggregator_feed']['title']['help'] = $this->t('The title of the aggregator feed.');
+    $data['aggregator_feed']['title']['field']['default_formatter'] = 'aggregator_title';
+
+    $data['aggregator_feed']['argument']['id'] = 'string';
+
+    $data['aggregator_feed']['url']['help'] = $this->t('The fully-qualified URL of the feed.');
+
+    $data['aggregator_feed']['link']['help'] = $this->t('The link to the source URL of the feed.');
+
+    $data['aggregator_feed']['checked']['help'] = $this->t('The date the feed was last checked for new content.');
+
+    $data['aggregator_feed']['description']['help'] = $this->t('The description of the aggregator feed.');
+    $data['aggregator_feed']['description']['field']['click sortable'] = FALSE;
+
+    $data['aggregator_feed']['modified']['help'] = $this->t('The date of the most recent new content on the feed.');
+
+    return $data;
+  }
+
+}

core/modules/aggregator/src/AggregatorItemViewsData.php

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+<?php
+
+/**
+ * @file
+ * Contains \Drupal\aggregator\AggregatorItemViewsData.
+ */
+
+namespace Drupal\aggregator;
+
+use Drupal\views\EntityViewsData;
+
+/**
+ * Provides the views data for the aggregator item entity type.
+ */
+class AggregatorItemViewsData extends EntityViewsData {
+
+  /**
+   * {@inheritdoc}
+   */
+  public function getViewsData() {
+    $data = parent::getViewsData();
+
+    $data['aggregator_item']['table']['base']['help'] = $this->t('Aggregator items are imported from external RSS and Atom news feeds.');
+
+    $data['aggregator_item']['iid']['help'] = $this->t('The unique ID of the aggregator item.');
+    $data['aggregator_item']['iid']['argument']['id'] = 'aggregator_iid';
+    $data['aggregator_item']['iid']['argument']['name field'] = 'title';
+    $data['aggregator_item']['iid']['argument']['numeric'] = TRUE;
+
+    $data['aggregator_item']['title']['help'] = $this->t('The title of the aggregator item.');
+    $data['aggregator_item']['title']['field']['default_formatter'] = 'aggregator_title';
+
+    $data['aggregator_item']['link']['help'] = $this->t('The link to the original source URL of the item.');
+
+    $data['aggregator_item']['author']['help'] = $this->t('The author of the original imported item.');
+
+    $data['aggregator_item']['author']['field']['default_formatter'] = 'aggregator_xss';
+
+    $data['aggregator_item']['guid']['help'] = $this->t('The guid of the original imported item.');
+
+    $data['aggregator_item']['description']['help'] = $this->t('The actual content of the imported item.');
+    $data['aggregator_item']['description']['field']['default_formatter'] = 'aggregator_xss';
+    $data['aggregator_item']['description']['field']['click sortable'] = FALSE;
+
+    $data['aggregator_item']['timestamp']['help'] = $this->t('The date the original feed item was posted. (With some feeds, this will be the date it was imported.)');
+
+    return $data;
+  }
+
+}

core/modules/aggregator/src/Annotation/AggregatorFetcher.php

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+<?php
+
+/**
+ * @file
+ * Contains \Drupal\aggregator\Annotation\AggregatorFetcher.
+ */
+
+namespace Drupal\aggregator\Annotation;
+
+use Drupal\Component\Annotation\Plugin;
+
+/**
+ * Defines a Plugin annotation object for aggregator fetcher plugins.
+ *
+ * Plugin Namespace: Plugin\aggregator\fetcher
+ *
+ * For a working example, see \Drupal\aggregator\Plugin\aggregator\fetcher\DefaultFetcher
+ *
+ * @see \Drupal\aggregator\Plugin\AggregatorPluginManager
+ * @see \Drupal\aggregator\Plugin\FetcherInterface
+ * @see \Drupal\aggregator\Plugin\AggregatorPluginSettingsBase
+ * @see plugin_api
+ *
+ * @Annotation
+ */
+class AggregatorFetcher extends Plugin {
+
+  /**
+   * The plugin ID.
+   *
+   * @var string
+   */
+  public $id;
+
+  /**
+   * The title of the plugin.
+   *
+   * @var \Drupal\Core\Annotation\Translation
+   *
+   * @ingroup plugin_translatable
+   */
+  public $title;
+
+  /**
+   * The description of the plugin.
+   *
+   * @var \Drupal\Core\Annotation\Translation
+   *
+   * @ingroup plugin_translatable
+   */
+  public $description;
+
+}

core/modules/aggregator/src/Annotation/AggregatorParser.php

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+<?php
+
+/**
+ * @file
+ * Contains \Drupal\aggregator\Annotation\AggregatorParser.
+ */
+
+namespace Drupal\aggregator\Annotation;
+
+use Drupal\Component\Annotation\Plugin;
+
+/**
+ * Defines a Plugin annotation object for aggregator parser plugins.
+ *
+ * Plugin Namespace: Plugin\aggregator\parser
+ *
+ * For a working example, see \Drupal\aggregator\Plugin\aggregator\parser\DefaultParser
+ *
+ * @see \Drupal\aggregator\Plugin\AggregatorPluginManager
+ * @see \Drupal\aggregator\Plugin\ParserInterface
+ * @see \Drupal\aggregator\Plugin\AggregatorPluginSettingsBase
+ * @see plugin_api
+ *
+ * @Annotation
+ */
+class AggregatorParser extends Plugin {
+
+  /**
+   * The plugin ID.
+   *
+   * @var string
+   */
+  public $id;
+
+  /**
+   * The title of the plugin.
+   *
+   * @var \Drupal\Core\Annotation\Translation
+   *
+   * @ingroup plugin_translatable
+   */
+  public $title;
+
+  /**
+   * The description of the plugin.
+   *
+   * @var \Drupal\Core\Annotation\Translation
+   *
+   * @ingroup plugin_translatable
+   */
+  public $description;
+
+}

core/modules/aggregator/src/Annotation/AggregatorProcessor.php

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+<?php
+
+/**
+ * @file
+ * Contains \Drupal\aggregator\Annotation\AggregatorProcessor.
+ */
+
+namespace Drupal\aggregator\Annotation;
+
+use Drupal\Component\Annotation\Plugin;
+
+/**
+ * Defines a Plugin annotation object for aggregator processor plugins.
+ *
+ * Plugin Namespace: Plugin\aggregator\processor
+ *
+ * For a working example, see \Drupal\aggregator\Plugin\aggregator\processor\DefaultProcessor
+ *
+ * @see \Drupal\aggregator\Plugin\AggregatorPluginManager
+ * @see \Drupal\aggregator\Plugin\ProcessorInterface
+ * @see \Drupal\aggregator\Plugin\AggregatorPluginSettingsBase
+ * @see plugin_api
+ *
+ * @Annotation
+ */
+class AggregatorProcessor extends Plugin {
+
+  /**
+   * The plugin ID.
+   *
+   * @var string
+   */
+  public $id;
+
+  /**
+   * The title of the plugin.
+   *
+   * @var \Drupal\Core\Annotation\Translation
+   *
+   * @ingroup plugin_translatable
+   */
+  public $title;
+
+  /**
+   * The description of the plugin.
+   *
+   * @var \Drupal\Core\Annotation\Translation
+   *
+   * @ingroup plugin_translatable
+   */
+  public $description;
+
+}

core/modules/aggregator/src/Controller/AggregatorController.php

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+<?php
+
+/**
+ * @file
+ * Contains \Drupal\aggregator\Controller\AggregatorController.
+ */
+
+namespace Drupal\aggregator\Controller;
+
+use Drupal\Component\Utility\Xss;
+use Drupal\Core\Controller\ControllerBase;
+use Drupal\Core\Datetime\DateFormatter;
+use Drupal\aggregator\FeedInterface;
+use Drupal\Core\Url;
+use Symfony\Component\HttpFoundation\Request;
+use Symfony\Component\HttpFoundation\Response;
+use Symfony\Component\DependencyInjection\ContainerInterface;
+
+/**
+ * Returns responses for aggregator module routes.
+ */
+class AggregatorController extends ControllerBase {
+
+  /**
+   * The date formatter service.
+   *
+   * @var \Drupal\Core\Datetime\DateFormatter
+   */
+  protected $dateFormatter;
+
+  /**
+   * Constructs a \Drupal\aggregator\Controller\AggregatorController object.
+   *
+   * @param \Drupal\Core\Datetime\DateFormatter $date_formatter
+   *    The date formatter service.
+   */
+  public function __construct(DateFormatter $date_formatter) {
+    $this->dateFormatter = $date_formatter;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public static function create(ContainerInterface $container) {
+    return new static(
+      $container->get('date.formatter')
+    );
+  }
+
+  /**
+   * Presents the aggregator feed creation form.
+   *
+   * @return array
+   *   A form array as expected by drupal_render().
+   */
+  public function feedAdd() {
+    $feed = $this->entityManager()->getStorage('aggregator_feed')
+      ->create(array(
+        'refresh' => 3600,
+      ));
+    return $this->entityFormBuilder()->getForm($feed);
+  }
+
+  /**
+   * Builds a listing of aggregator feed items.
+   *
+   * @param \Drupal\aggregator\ItemInterface[] $items
+   *   The items to be listed.
+   * @param array|string $feed_source
+   *   The feed source URL.
+   *
+   * @return array
+   *   The rendered list of items for the feed.
+   */
+  protected function buildPageList(array $items, $feed_source = '') {
+    // Assemble output.
+    $build = array(
+      '#type' => 'container',
+      '#attributes' => array('class' => array('aggregator-wrapper')),
+    );
+    $build['feed_source'] = is_array($feed_source) ? $feed_source : array('#markup' => $feed_source);
+    if ($items) {
+      $build['items'] = $this->entityManager()->getViewBuilder('aggregator_item')
+        ->viewMultiple($items, 'default');
+      $build['pager'] = array('#type' => 'pager');
+    }
+    return $build;
+  }
+
+  /**
+   * Refreshes a feed, then redirects to the overview page.
+   *
+   * @param \Drupal\aggregator\FeedInterface $aggregator_feed
+   *   An object describing the feed to be refreshed.
+   *
+   * @return \Symfony\Component\HttpFoundation\RedirectResponse
+   *   A redirection to the admin overview page.
+   *
+   * @throws \Symfony\Component\HttpKernel\Exception\AccessDeniedHttpException
+   *   If the query token is missing or invalid.
+   */
+  public function feedRefresh(FeedInterface $aggregator_feed) {
+    $message = $aggregator_feed->refreshItems()
+      ? $this->t('There is new syndicated content from %site.', array('%site' => $aggregator_feed->label()))
+      : $this->t('There is no new syndicated content from %site.', array('%site' => $aggregator_feed->label()));
+    drupal_set_message($message);
+    return $this->redirect('aggregator.admin_overview');
+  }
+
+  /**
+   * Displays the aggregator administration page.
+   *
+   * @return array
+   *   A render array as expected by drupal_render().
+   */
+  public function adminOverview() {
+    $entity_manager = $this->entityManager();
+    $feeds = $entity_manager->getStorage('aggregator_feed')
+      ->loadMultiple();
+
+    $header = array($this->t('Title'), $this->t('Items'), $this->t('Last update'), $this->t('Next update'), $this->t('Operations'));
+    $rows = array();
+    /** @var \Drupal\aggregator\FeedInterface[] $feeds */
+    foreach ($feeds as $feed) {
+      $row = array();
+      $row[] = $feed->link();
+      $row[] = $this->formatPlural($entity_manager->getStorage('aggregator_item')->getItemCount($feed), '1 item', '@count items');
+      $last_checked = $feed->getLastCheckedTime();
+      $refresh_rate = $feed->getRefreshRate();
+      $row[] = ($last_checked ? $this->t('@time ago', array('@time' => $this->dateFormatter->formatTimeDiffSince($last_checked))) : $this->t('never'));
+      $row[] = ($last_checked && $refresh_rate ? $this->t('@time left', array('@time' => $this->dateFormatter->formatTimeDiffUntil($last_checked + $refresh_rate))) : $this->t('never'));
+      $links['edit'] = [
+        'title' => $this->t('Edit'),
+        'url' => Url::fromRoute('entity.aggregator_feed.edit_form', ['aggregator_feed' => $feed->id()]),
+      ];
+      $links['delete'] = array(
+        'title' => $this->t('Delete'),
+        'url' => Url::fromRoute('entity.aggregator_feed.delete_form', ['aggregator_feed' => $feed->id()]),
+      );
+      $links['delete_items'] = array(
+        'title' => $this->t('Delete items'),
+        'url' => Url::fromRoute('aggregator.feed_items_delete', ['aggregator_feed' => $feed->id()]),
+      );
+      $links['update'] = array(
+        'title' => $this->t('Update items'),
+        'url' => Url::fromRoute('aggregator.feed_refresh', ['aggregator_feed' => $feed->id()]),
+      );
+      $row[] = array(
+        'data' => array(
+          '#type' => 'operations',
+          '#links' => $links,
+        ),
+      );
+      $rows[] = $row;
+    }
+    $build['feeds'] = array(
+      '#prefix' => '<h3>' . $this->t('Feed overview') . '</h3>',
+      '#type' => 'table',
+      '#header' => $header,
+      '#rows' => $rows,
+      '#empty' => $this->t('No feeds available. <a href="@link">Add feed</a>.', array('@link' => $this->url('aggregator.feed_add'))),
+    );
+
+    return $build;
+  }
+
+  /**
+   * Displays the most recent items gathered from any feed.
+   *
+   * @return string
+   *   The rendered list of items for the feed.
+   */
+  public function pageLast() {
+    $items = $this->entityManager()->getStorage('aggregator_item')->loadAll(20);
+    $build = $this->buildPageList($items);
+    $build['#attached']['feed'][] = array('aggregator/rss', $this->config('system.site')->get('name') . ' ' . $this->t('aggregator'));
+    return $build;
+  }
+
+  /**
+   * Route title callback.
+   *
+   * @param \Drupal\aggregator\FeedInterface $aggregator_feed
+   *   The aggregator feed.
+   *
+   * @return string
+   *   The feed label.
+   */
+  public function feedTitle(FeedInterface $aggregator_feed) {
+    return Xss::filter($aggregator_feed->label());
+  }
+
+}

core/modules/aggregator/src/Entity/Feed.php

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+<?php
+
+/**
+ * @file
+ * Contains \Drupal\aggregator\Entity\Feed.
+ */
+
+namespace Drupal\aggregator\Entity;
+
+use Drupal\Core\Entity\ContentEntityBase;
+use Drupal\Core\Entity\EntityTypeInterface;
+use Drupal\Core\Field\BaseFieldDefinition;
+use Symfony\Component\DependencyInjection\Container;
+use Drupal\Core\Entity\EntityStorageInterface;
+use Drupal\aggregator\FeedInterface;
+
+/**
+ * Defines the aggregator feed entity class.
+ *
+ * @ContentEntityType(
+ *   id = "aggregator_feed",
+ *   label = @Translation("Aggregator feed"),
+ *   handlers = {
+ *     "storage" = "Drupal\aggregator\FeedStorage",
+ *     "storage_schema" = "Drupal\aggregator\FeedStorageSchema",
+ *     "view_builder" = "Drupal\aggregator\FeedViewBuilder",
+ *     "access" = "Drupal\aggregator\FeedAccessControlHandler",
+ *     "views_data" = "Drupal\aggregator\AggregatorFeedViewsData",
+ *     "form" = {
+ *       "default" = "Drupal\aggregator\FeedForm",
+ *       "delete" = "Drupal\aggregator\Form\FeedDeleteForm",
+ *       "delete_items" = "Drupal\aggregator\Form\FeedItemsDeleteForm",
+ *     }
+ *   },
+ *   links = {
+ *     "canonical" = "/aggregator/sources/{aggregator_feed}",
+ *     "edit-form" = "/aggregator/sources/{aggregator_feed}/configure",
+ *     "delete-form" = "/aggregator/sources/{aggregator_feed}/delete",
+ *   },
+ *   field_ui_base_route = "aggregator.admin_overview",
+ *   base_table = "aggregator_feed",
+ *   render_cache = FALSE,
+ *   entity_keys = {
+ *     "id" = "fid",
+ *     "label" = "title",
+ *     "langcode" = "langcode",
+ *     "uuid" = "uuid",
+ *   }
+ * )
+ */
+class Feed extends ContentEntityBase implements FeedInterface {
+
+  /**
+   * Implements Drupal\Core\Entity\EntityInterface::label().
+   */
+  public function label() {
+    return $this->get('title')->value;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function deleteItems() {
+    \Drupal::service('aggregator.items.importer')->delete($this);
+
+    // Reset feed.
+    $this->setLastCheckedTime(0);
+    $this->setHash('');
+    $this->setEtag('');
+    $this->setLastModified(0);
+    $this->save();
+
+    return $this;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function refreshItems() {
+    $success = \Drupal::service('aggregator.items.importer')->refresh($this);
+
+    // Regardless of successful or not, indicate that it has been checked.
+    $this->setLastCheckedTime(REQUEST_TIME);
+    $this->setQueuedTime(0);
+    $this->save();
+
+    return $success;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public static function preCreate(EntityStorageInterface $storage, array &$values) {
+    $values += array(
+      'link' => '',
+      'description' => '',
+      'image' => '',
+    );
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public static function preDelete(EntityStorageInterface $storage, array $entities) {
+    foreach ($entities as $entity) {
+      // Notify processors to delete stored items.
+      \Drupal::service('aggregator.items.importer')->delete($entity);
+    }
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public static function postDelete(EntityStorageInterface $storage, array $entities) {
+    parent::postDelete($storage, $entities);
+    if (\Drupal::moduleHandler()->moduleExists('block')) {
+      // Make sure there are no active blocks for these feeds.
+      $ids = \Drupal::entityQuery('block')
+        ->condition('plugin', 'aggregator_feed_block')
+        ->condition('settings.feed', array_keys($entities))
+        ->execute();
+      if ($ids) {
+        $block_storage = \Drupal::entityManager()->getStorage('block');
+        $block_storage->delete($block_storage->loadMultiple($ids));
+      }
+    }
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public static function baseFieldDefinitions(EntityTypeInterface $entity_type) {
+    $fields['fid'] = BaseFieldDefinition::create('integer')
+      ->setLabel(t('Feed ID'))
+      ->setDescription(t('The ID of the aggregator feed.'))
+      ->setReadOnly(TRUE)
+      ->setSetting('unsigned', TRUE);
+
+    $fields['uuid'] = BaseFieldDefinition::create('uuid')
+      ->setLabel(t('UUID'))
+      ->setDescription(t('The aggregator feed UUID.'))
+      ->setReadOnly(TRUE);
+
+    $fields['title'] = BaseFieldDefinition::create('string')
+      ->setLabel(t('Title'))
+      ->setDescription(t('The name of the feed (or the name of the website providing the feed).'))
+      ->setRequired(TRUE)
+      ->setSetting('max_length', 255)
+      ->setDisplayOptions('form', array(
+        'type' => 'string_textfield',
+        'weight' => -5,
+      ))
+      ->setDisplayConfigurable('form', TRUE)
+      ->addConstraint('FeedTitle', []);
+
+    $fields['langcode'] = BaseFieldDefinition::create('language')
+      ->setLabel(t('Language code'))
+      ->setDescription(t('The feed language code.'))
+      ->setDisplayOptions('view', array(
+        'type' => 'hidden',
+      ))
+      ->setDisplayOptions('form', array(
+        'type' => 'language_select',
+        'weight' => 2,
+      ));
+
+    $fields['url'] = BaseFieldDefinition::create('uri')
+      ->setLabel(t('URL'))
+      ->setDescription(t('The fully-qualified URL of the feed.'))
+      ->setRequired(TRUE)
+      ->setDisplayOptions('form', array(
+        'type' => 'uri',
+        'weight' => -3,
+      ))
+      ->setDisplayConfigurable('form', TRUE)
+      ->addConstraint('FeedUrl', []);
+
+    $intervals = array(900, 1800, 3600, 7200, 10800, 21600, 32400, 43200, 64800, 86400, 172800, 259200, 604800, 1209600, 2419200);
+    $period = array_map(array(\Drupal::service('date.formatter'), 'formatInterval'), array_combine($intervals, $intervals));
+    $period[AGGREGATOR_CLEAR_NEVER] = t('Never');
+
+    $fields['refresh'] = BaseFieldDefinition::create('list_integer')
+      ->setLabel(t('Update interval'))
+      ->setDescription(t('The length of time between feed updates. Requires a correctly configured cron maintenance task.'))
+      ->setSetting('unsigned', TRUE)
+      ->setRequired(TRUE)
+      ->setSetting('allowed_values', $period)
+      ->setDisplayOptions('form', array(
+        'type' => 'options_select',
+        'weight' => -2,
+      ))
+      ->setDisplayConfigurable('form', TRUE);
+
+    $fields['checked'] = BaseFieldDefinition::create('timestamp')
+      ->setLabel(t('Checked'))
+      ->setDescription(t('Last time feed was checked for new items, as Unix timestamp.'))
+      ->setDefaultValue(0)
+      ->setDisplayOptions('view', array(
+        'label' => 'inline',
+        'type' => 'timestamp_ago',
+        'weight' => 1,
+      ))
+      ->setDisplayConfigurable('view', TRUE);
+
+    $fields['queued'] = BaseFieldDefinition::create('timestamp')
+      ->setLabel(t('Queued'))
+      ->setDescription(t('Time when this feed was queued for refresh, 0 if not queued.'))
+      ->setDefaultValue(0);
+
+    $fields['link'] = BaseFieldDefinition::create('uri')
+      ->setLabel(t('URL'))
+      ->setDescription(t('The link of the feed.'))
+      ->setDisplayOptions('view', array(
+        'label' => 'inline',
+        'weight' => 4,
+      ))
+      ->setDisplayConfigurable('view', TRUE);
+
+    $fields['description'] = BaseFieldDefinition::create('string_long')
+      ->setLabel(t('Description'))
+      ->setDescription(t("The parent website's description that comes from the !description element in the feed.", array('!description' => '<description>')));
+
+    $fields['image'] = BaseFieldDefinition::create('uri')
+      ->setLabel(t('Image'))
+      ->setDescription(t('An image representing the feed.'));
+
+    $fields['hash'] = BaseFieldDefinition::create('string')
+      ->setLabel(t('Hash'))
+      ->setSetting('is_ascii', TRUE)
+      ->setDescription(t('Calculated hash of the feed data, used for validating cache.'));
+
+    $fields['etag'] = BaseFieldDefinition::create('string')
+      ->setLabel(t('Etag'))
+      ->setDescription(t('Entity tag HTTP response header, used for validating cache.'));
+
+    // This is updated by the fetcher and not when the feed is saved, therefore
+    // it's a timestamp and not a changed field.
+    $fields['modified'] = BaseFieldDefinition::create('timestamp')
+      ->setLabel(t('Modified'))
+      ->setDescription(t('When the feed was last modified, as a Unix timestamp.'));
+
+    return $fields;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function getUrl() {
+    return $this->get('url')->value;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function getRefreshRate() {
+    return $this->get('refresh')->value;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function getLastCheckedTime() {
+    return $this->get('checked')->value;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function getQueuedTime() {
+    return $this->get('queued')->value;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function getWebsiteUrl() {
+    return $this->get('link')->value;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function getDescription() {
+    return $this->get('description')->value;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function getImage() {
+    return $this->get('image')->value;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function getHash() {
+    return $this->get('hash')->value;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function getEtag() {
+    return $this->get('etag')->value;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function getLastModified() {
+    return $this->get('modified')->value;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function setTitle($title) {
+    $this->set('title', $title);
+    return $this;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function setUrl($url) {
+    $this->set('url', $url);
+    return $this;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function setRefreshRate($refresh) {
+    $this->set('refresh', $refresh);
+    return $this;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function setLastCheckedTime($checked) {
+    $this->set('checked', $checked);
+    return $this;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function setQueuedTime($queued) {
+    $this->set('queued', $queued);
+    return $this;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function setWebsiteUrl($link) {
+    $this->set('link', $link);
+    return $this;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function setDescription($description) {
+    $this->set('description', $description);
+    return $this;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function setImage($image) {
+    $this->set('image', $image);
+    return $this;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function setHash($hash) {
+    $this->set('hash', $hash);
+    return $this;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function setEtag($etag) {
+    $this->set('etag', $etag);
+    return $this;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function setLastModified($modified) {
+    $this->set('modified', $modified);
+    return $this;
+  }
+
+}

core/modules/aggregator/src/Entity/Item.php

@@ -0,0 +1,246 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\aggregator\Entity\Item.
+ */
+
+namespace Drupal\aggregator\Entity;
+
+use Drupal\Core\Cache\Cache;
+use Drupal\Core\Entity\ContentEntityBase;
+use Drupal\Core\Entity\EntityStorageInterface;
+use Drupal\aggregator\ItemInterface;
+use Drupal\Core\Entity\EntityTypeInterface;
+use Drupal\Core\Field\BaseFieldDefinition;
+use Drupal\Core\Url;
+
+/**
+ * Defines the aggregator item entity class.
+ *
+ * @ContentEntityType(
+ *   id = "aggregator_item",
+ *   label = @Translation("Aggregator feed item"),
+ *   handlers = {
+ *     "storage" = "Drupal\aggregator\ItemStorage",
+ *     "storage_schema" = "Drupal\aggregator\ItemStorageSchema",
+ *     "view_builder" = "Drupal\aggregator\ItemViewBuilder",
+ *     "access" = "Drupal\aggregator\FeedAccessControlHandler",
+ *     "views_data" = "Drupal\aggregator\AggregatorItemViewsData"
+ *   },
+ *   uri_callback = "Drupal\aggregator\Entity\Item::buildUri",
+ *   base_table = "aggregator_item",
+ *   render_cache = FALSE,
+ *   list_cache_tags = { "aggregator_feed_list" },
+ *   entity_keys = {
+ *     "id" = "iid",
+ *     "label" = "title",
+ *     "langcode" = "langcode",
+ *   }
+ * )
+ */
+class Item extends ContentEntityBase implements ItemInterface {
+
+  /**
+   * Implements Drupal\Core\Entity\EntityInterface::label().
+   */
+  public function label() {
+    return $this->get('title')->value;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public static function baseFieldDefinitions(EntityTypeInterface $entity_type) {
+    $fields['iid'] = BaseFieldDefinition::create('integer')
+      ->setLabel(t('Aggregator item ID'))
+      ->setDescription(t('The ID of the feed item.'))
+      ->setReadOnly(TRUE)
+      ->setSetting('unsigned', TRUE);
+
+    $fields['fid'] = BaseFieldDefinition::create('entity_reference')
+      ->setLabel(t('Source feed'))
+      ->setDescription(t('The aggregator feed entity associated with this item.'))
+      ->setSetting('target_type', 'aggregator_feed')
+      ->setDisplayOptions('view', array(
+        'label' => 'hidden',
+        'type' => 'entity_reference_label',
+        'weight' => 0,
+      ))
+      ->setDisplayConfigurable('form', TRUE);
+
+    $fields['title'] = BaseFieldDefinition::create('string')
+      ->setLabel(t('Title'))
+      ->setDescription(t('The title of the feed item.'));
+
+    $fields['langcode'] = BaseFieldDefinition::create('language')
+      ->setLabel(t('Language code'))
+      ->setDescription(t('The feed item language code.'));
+
+    $fields['link'] = BaseFieldDefinition::create('uri')
+      ->setLabel(t('Link'))
+      ->setDescription(t('The link of the feed item.'))
+      ->setDisplayOptions('view', array(
+        'type' => 'hidden',
+      ))
+      ->setDisplayConfigurable('view', TRUE);
+
+    $fields['author'] = BaseFieldDefinition::create('string')
+      ->setLabel(t('Author'))
+      ->setDescription(t('The author of the feed item.'))
+      ->setDisplayOptions('view', array(
+        'label' => 'hidden',
+        'weight' => 3,
+      ))
+      ->setDisplayConfigurable('view', TRUE);
+
+    $fields['description'] = BaseFieldDefinition::create('string_long')
+      ->setLabel(t('Description'))
+      ->setDescription(t('The body of the feed item.'));
+
+    $fields['timestamp'] = BaseFieldDefinition::create('created')
+      ->setLabel(t('Posted on'))
+      ->setDescription(t('Posted date of the feed item, as a Unix timestamp.'))
+      ->setDisplayOptions('view', array(
+        'label' => 'hidden',
+        'type' => 'timestamp_ago',
+        'weight' => 1,
+      ))
+      ->setDisplayConfigurable('view', TRUE);
+
+    // @todo Convert to a real UUID field in
+    //   https://www.drupal.org/node/2149851.
+    $fields['guid'] = BaseFieldDefinition::create('string_long')
+      ->setLabel(t('GUID'))
+      ->setDescription(t('Unique identifier for the feed item.'));
+
+    return $fields;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function getFeedId() {
+    return $this->get('fid')->target_id;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function setFeedId($fid) {
+    return $this->set('fid', $fid);
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function getTitle() {
+    return $this->get('title')->value;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function setTitle($title) {
+    return $this->set('title', $title);
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function getLink() {
+    return $this->get('link')->value;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function setLink($link) {
+    return $this->set('link', $link);
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function getAuthor() {
+    return $this->get('author')->value;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function setAuthor($author) {
+    return $this->set('author', $author);
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function getDescription() {
+    return $this->get('description')->value;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function setDescription($description) {
+    return $this->set('description', $description);
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function getPostedTime() {
+    return $this->get('timestamp')->value;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function setPostedTime($timestamp) {
+    return $this->set('timestamp', $timestamp);
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function getGuid() {
+    return $this->get('guid')->value;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function setGuid($guid) {
+    return $this->set('guid', $guid);
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function postSave(EntityStorageInterface $storage, $update = TRUE) {
+    parent::postSave($storage, $update);
+
+    // Entity::postSave() calls Entity::invalidateTagsOnSave(), which only
+    // handles the regular cases. The Item entity has one special case: a newly
+    // created Item is *also* associated with a Feed, so we must invalidate the
+    // associated Feed's cache tag.
+    Cache::invalidateTags($this->getCacheTags());
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function getCacheTags() {
+    return Feed::load($this->getFeedId())->getCacheTags();
+  }
+
+
+  /**
+   * Entity URI callback.
+   */
+  public static function buildUri(ItemInterface $item) {
+    return Url::fromUri($item->getLink());
+  }
+
+}

core/modules/aggregator/src/FeedAccessControlHandler.php

@@ -0,0 +1,44 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\aggregator\FeedAccessControlHandler.
+ */
+
+namespace Drupal\aggregator;
+
+use Drupal\Core\Access\AccessResult;
+use Drupal\Core\Entity\EntityAccessControlHandler;
+use Drupal\Core\Entity\EntityInterface;
+use Drupal\Core\Session\AccountInterface;
+
+/**
+ * Defines an access control handler for the feed entity.
+ *
+ * @see \Drupal\aggregator\Entity\Feed
+ */
+class FeedAccessControlHandler extends EntityAccessControlHandler {
+
+  /**
+   * {@inheritdoc}
+   */
+  protected function checkAccess(EntityInterface $entity, $operation, $langcode, AccountInterface $account) {
+    switch ($operation) {
+      case 'view':
+        return AccessResult::allowedIfHasPermission($account, 'access news feeds');
+        break;
+
+      default:
+        return AccessResult::allowedIfHasPermission($account, 'administer news feeds');
+        break;
+    }
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  protected function checkCreateAccess(AccountInterface $account, array $context, $entity_bundle = NULL) {
+    return AccessResult::allowedIfHasPermission($account, 'administer news feeds');
+  }
+
+}

core/modules/aggregator/src/FeedForm.php

@@ -0,0 +1,36 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\aggregator\FeedForm.
+ */
+
+namespace Drupal\aggregator;
+
+use Drupal\Core\Entity\ContentEntityForm;
+use Drupal\Core\Form\FormStateInterface;
+use Drupal\Core\Url;
+
+/**
+ * Form controller for the aggregator feed edit forms.
+ */
+class FeedForm extends ContentEntityForm {
+
+  /**
+   * {@inheritdoc}
+   */
+  public function save(array $form, FormStateInterface $form_state) {
+    $feed = $this->entity;
+    $insert = (bool) $feed->id();
+    $feed->save();
+    if ($insert) {
+      drupal_set_message($this->t('The feed %feed has been updated.', array('%feed' => $feed->label())));
+      $form_state->setRedirectUrl($feed->urlInfo('canonical'));
+    }
+    else {
+      $this->logger('aggregator')->notice('Feed %feed added.', array('%feed' => $feed->label(), 'link' => $this->l($this->t('View'), new Url('aggregator.admin_overview'))));
+      drupal_set_message($this->t('The feed %feed has been added.', array('%feed' => $feed->label())));
+    }
+  }
+
+}

core/modules/aggregator/src/FeedInterface.php

@@ -0,0 +1,244 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\aggregator\FeedInterface.
+ */
+
+namespace Drupal\aggregator;
+
+use Drupal\Core\Entity\ContentEntityInterface;
+
+/**
+ * Provides an interface defining an aggregator feed entity.
+ */
+interface FeedInterface extends ContentEntityInterface {
+
+  /**
+   * Sets the title of the feed.
+   *
+   * @param string $title
+   *   The short title of the feed.
+   *
+   * @return \Drupal\aggregator\FeedInterface
+   *   The class instance that this method is called on.
+   */
+  public function setTitle($title);
+
+  /**
+   * Returns the url to the feed.
+   *
+   * @return string
+   *   The url to the feed.
+   */
+  public function getUrl();
+
+  /**
+   * Sets the url to the feed.
+   *
+   * @param string $url
+   *   A string containing the url of the feed.
+   *
+   * @return \Drupal\aggregator\FeedInterface
+   *   The class instance that this method is called on.
+   */
+  public function setUrl($url);
+
+  /**
+   * Returns the refresh rate of the feed in seconds.
+   *
+   * @return int
+   *   The refresh rate of the feed in seconds.
+   */
+  public function getRefreshRate();
+
+  /**
+   * Sets the refresh rate of the feed in seconds.
+   *
+   * @param int $refresh
+   *   The refresh rate of the feed in seconds.
+   *
+   * @return \Drupal\aggregator\FeedInterface
+   *   The class instance that this method is called on.
+   */
+  public function setRefreshRate($refresh);
+
+  /**
+   * Returns the last time where the feed was checked for new items.
+   *
+   * @return int
+   *   The timestamp when new items were last checked for.
+   */
+  public function getLastCheckedTime();
+
+  /**
+   * Sets the time when this feed was queued for refresh, 0 if not queued.
+   *
+   * @param int $checked
+   *   The timestamp of the last refresh.
+   *
+   * @return \Drupal\aggregator\FeedInterface
+   *   The class instance that this method is called on.
+   */
+  public function setLastCheckedTime($checked);
+
+  /**
+   * Returns the time when this feed was queued for refresh, 0 if not queued.
+   *
+   * @return int
+   *   The timestamp of the last refresh.
+   */
+  public function getQueuedTime();
+
+  /**
+   * Sets the time when this feed was queued for refresh, 0 if not queued.
+   *
+   * @param int $queued
+   *   The timestamp of the last refresh.
+   *
+   * @return \Drupal\aggregator\FeedInterface
+   *   The class instance that this method is called on.
+   */
+  public function setQueuedTime($queued);
+
+  /**
+   * Returns the parent website of the feed.
+   *
+   * @return string
+   *   The parent website of the feed.
+   */
+  public function getWebsiteUrl();
+
+  /**
+   * Sets the parent website of the feed.
+   *
+   * @param string $link
+   *   A string containing the parent website of the feed.
+   *
+   * @return \Drupal\aggregator\FeedInterface
+   *   The class instance that this method is called on.
+   */
+  public function setWebsiteUrl($link);
+
+  /**
+   * Returns the description of the feed.
+   *
+   * @return string
+   *   The description of the feed.
+   */
+  public function getDescription();
+
+  /**
+   * Sets the description of the feed.
+   *
+   * @param string $description
+   *   The description of the feed.
+   *
+   * @return \Drupal\aggregator\FeedInterface
+   *   The class instance that this method is called on.
+   */
+  public function setDescription($description);
+
+  /**
+   * Returns the primary image attached to the feed.
+   *
+   * @return string
+   *   The URL of the primary image attached to the feed.
+   */
+  public function getImage();
+
+  /**
+   * Sets the primary image attached to the feed.
+   *
+   * @param string $image
+   *   An image URL.
+   *
+   * @return \Drupal\aggregator\FeedInterface
+   *   The class instance that this method is called on.
+   */
+  public function setImage($image);
+
+  /**
+   * Returns the calculated hash of the feed data, used for validating cache.
+   *
+   * @return string
+   *   The calculated hash of the feed data.
+   */
+  public function getHash();
+
+  /**
+   * Sets the calculated hash of the feed data, used for validating cache.
+   *
+   * @param string $hash
+   *   A string containing the calculated hash of the feed. Must contain
+   *   US ASCII characters only.
+   *
+   * @return \Drupal\aggregator\FeedInterface
+   *   The class instance that this method is called on.
+   */
+  public function setHash($hash);
+
+  /**
+   * Returns the entity tag HTTP response header, used for validating cache.
+   *
+   * @return string
+   *   The entity tag HTTP response header.
+   */
+  public function getEtag();
+
+  /**
+   * Sets the entity tag HTTP response header, used for validating cache.
+   *
+   * @param string $etag
+   *   A string containing the entity tag HTTP response header.
+   *
+   * @return \Drupal\aggregator\FeedInterface
+   *   The class instance that this method is called on.
+   */
+  public function setEtag($etag);
+
+  /**
+   * Return when the feed was modified last time.
+   *
+   * @return int
+   *   The timestamp of the last time the feed was modified.
+   */
+  public function getLastModified();
+
+  /**
+   * Sets the last modification of the feed.
+   *
+   * @param int $modified
+   *   The timestamp when the feed was modified.
+   *
+   * @return \Drupal\aggregator\FeedInterface
+   *   The class instance that this method is called on.
+   */
+  public function setLastModified($modified);
+
+  /**
+   * Deletes all items from a feed.
+   *
+   * This will also reset the last checked and modified time of the feed and
+   * save it.
+   *
+   * @return \Drupal\aggregator\FeedInterface
+   *   The class instance that this method is called on.
+   *
+   * @see \Drupal\aggregator\ItemsImporterInterface::delete()
+   */
+  public function deleteItems();
+
+  /**
+   * Updates the feed items by triggering the import process.
+   *
+   * This will also update the last checked time of the feed and save it.
+   *
+   * @return bool
+   *   TRUE if there is new content for the feed FALSE otherwise.
+   *
+   * @see \Drupal\aggregator\ItemsImporterInterface::refresh()
+   */
+  public function refreshItems();
+
+}

core/modules/aggregator/src/FeedStorage.php

@@ -0,0 +1,30 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\aggregator\FeedStorage.
+ */
+
+namespace Drupal\aggregator;
+
+use Drupal\Core\Entity\Sql\SqlContentEntityStorage;
+
+/**
+ * Controller class for aggregator's feeds.
+ *
+ * This extends the Drupal\Core\Entity\Sql\SqlContentEntityStorage class, adding
+ * required special handling for feed entities.
+ */
+class FeedStorage extends SqlContentEntityStorage implements FeedStorageInterface {
+
+  /**
+   * {@inheritdoc}
+   */
+  public function getFeedIdsToRefresh() {
+    return $this->database->query('SELECT fid FROM {aggregator_feed} WHERE queued = 0 AND checked + refresh < :time AND refresh <> :never', array(
+      ':time' => REQUEST_TIME,
+      ':never' => AGGREGATOR_CLEAR_NEVER,
+    ))->fetchCol();
+  }
+
+}

core/modules/aggregator/src/FeedStorageInterface.php

@@ -0,0 +1,26 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\aggregator\FeedStorageInterface.
+ */
+
+namespace Drupal\aggregator;
+
+use Drupal\aggregator\FeedInterface;
+use Drupal\Core\Entity\EntityStorageInterface;
+
+/**
+ * Defines an interface for aggregator feed entity storage classes.
+ */
+interface FeedStorageInterface extends EntityStorageInterface {
+
+  /**
+   * Returns the fids of feeds that need to be refreshed.
+   *
+   * @return array
+   *   A list of feed ids to be refreshed.
+   */
+  public function getFeedIdsToRefresh();
+
+}

core/modules/aggregator/src/FeedStorageSchema.php

@@ -0,0 +1,44 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\aggregator\FeedStorageSchema.
+ */
+
+namespace Drupal\aggregator;
+
+use Drupal\Core\Entity\Sql\SqlContentEntityStorageSchema;
+use Drupal\Core\Field\FieldStorageDefinitionInterface;
+
+/**
+ * Defines the feed schema handler.
+ */
+class FeedStorageSchema extends SqlContentEntityStorageSchema {
+
+  /**
+   * {@inheritdoc}
+   */
+  protected function getSharedTableFieldSchema(FieldStorageDefinitionInterface $storage_definition, $table_name, array $column_mapping) {
+    $schema = parent::getSharedTableFieldSchema($storage_definition, $table_name, $column_mapping);
+    $field_name = $storage_definition->getName();
+
+    if ($table_name == 'aggregator_feed') {
+      switch ($field_name) {
+        case 'url':
+          $this->addSharedTableFieldIndex($storage_definition, $schema, TRUE, 255);
+          break;
+
+        case 'queued':
+          $this->addSharedTableFieldIndex($storage_definition, $schema, TRUE);
+          break;
+
+        case 'title':
+          $this->addSharedTableFieldIndex($storage_definition, $schema, TRUE);
+          break;
+      }
+    }
+
+    return $schema;
+  }
+
+}

core/modules/aggregator/src/FeedViewBuilder.php

@@ -0,0 +1,139 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\aggregator\FeedViewBuilder.
+ */
+
+namespace Drupal\aggregator;
+
+use Drupal\Core\Entity\EntityManagerInterface;
+use Drupal\Core\Entity\EntityTypeInterface;
+use Drupal\Core\Entity\EntityViewBuilder;
+use Drupal\Core\Config\Config;
+use Drupal\Core\Language\LanguageManagerInterface;
+use Drupal\Core\Url;
+use Symfony\Component\DependencyInjection\ContainerInterface;
+
+/**
+ * Render controller for aggregator feed items.
+ */
+class FeedViewBuilder extends EntityViewBuilder {
+
+  /**
+   * Constructs a new FeedViewBuilder.
+   *
+   * @param \Drupal\Core\Entity\EntityTypeInterface $entity_type
+   *   The entity type definition.
+   * @param \Drupal\Core\Entity\EntityManagerInterface $entity_manager
+   *   The entity manager service.
+   * @param \Drupal\Core\Language\LanguageManagerInterface $language_manager
+   *   The language manager.
+   * @param \Drupal\Core\Config\Config $config
+   *   The 'aggregator.settings' config.
+   */
+  public function __construct(EntityTypeInterface $entity_type, EntityManagerInterface $entity_manager, LanguageManagerInterface $language_manager, Config $config) {
+    parent::__construct($entity_type, $entity_manager, $language_manager);
+    $this->config = $config;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public static function createInstance(ContainerInterface $container, EntityTypeInterface $entity_type) {
+    return new static(
+      $entity_type,
+      $container->get('entity.manager'),
+      $container->get('language_manager'),
+      $container->get('config.factory')->get('aggregator.settings')
+    );
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function buildComponents(array &$build, array $entities, array $displays, $view_mode, $langcode = NULL) {
+    parent::buildComponents($build, $entities, $displays, $view_mode, $langcode);
+
+    foreach ($entities as $id => $entity) {
+      $bundle = $entity->bundle();
+      $display = $displays[$bundle];
+
+      if ($display->getComponent('items')) {
+        // When in summary view mode, respect the list_max setting.
+        $limit = $view_mode == 'summary' ? $this->config->get('source.list_max') : 20;
+        // Retrieve the items attached to this feed.
+        $items = $this->entityManager
+          ->getStorage('aggregator_item')
+          ->loadByFeed($entity->id(), $limit);
+
+        $build[$id]['items'] = $this->entityManager
+          ->getViewBuilder('aggregator_item')
+          ->viewMultiple($items, $view_mode, $langcode);
+
+        if ($view_mode == 'full') {
+          // Also add the pager.
+          $build[$id]['pager'] = array('#type' => 'pager');
+        }
+      }
+
+      if ($display->getComponent('description')) {
+        $build[$id]['description'] = array(
+          '#markup' => aggregator_filter_xss($entity->getDescription()),
+          '#prefix' => '<div class="feed-description">',
+          '#suffix' => '</div>',
+        );
+      }
+
+      if ($display->getComponent('image')) {
+        $image_link = array();
+        // Render the image as link if it is available.
+        $image = $entity->getImage();
+        $label = $entity->label();
+        $link_href = $entity->getWebsiteUrl();
+        if ($image && $label && $link_href) {
+          $link_title = array(
+            '#theme' => 'image',
+            '#uri' => $image,
+            '#alt' => $label,
+          );
+          $image_link = array(
+            '#type' => 'link',
+            '#title' => $link_title,
+            '#url' => Url::fromUri($link_href),
+            '#options' => array(
+              'attributes' => array('class' => array('feed-image')),
+            ),
+          );
+        }
+        $build[$id]['image'] = $image_link;
+      }
+
+      if ($display->getComponent('feed_icon')) {
+        $build[$id]['feed_icon'] = array(
+          '#theme' => 'feed_icon',
+          '#url' => $entity->getUrl(),
+          '#title' => t('!title feed', array('!title' => $entity->label())),
+        );
+      }
+
+      if ($display->getComponent('more_link')) {
+        $title_stripped = strip_tags($entity->label());
+        $build[$id]['more_link'] = array(
+          '#type' => 'link',
+          '#title' => t('More<span class="visually-hidden"> posts about @title</span>', array(
+            '@title' => $title_stripped,
+          )),
+          '#url' => Url::fromRoute('entity.aggregator_feed.canonical', ['aggregator_feed' => $entity->id()]),
+          '#options' => array(
+            'attributes' => array(
+              'title' => $title_stripped,
+            ),
+          ),
+        );
+      }
+
+    }
+  }
+
+}

core/modules/aggregator/src/Form/FeedDeleteForm.php

@@ -0,0 +1,41 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\aggregator\Form\FeedDeleteForm.
+ */
+
+namespace Drupal\aggregator\Form;
+
+use Drupal\Core\Entity\ContentEntityDeleteForm;
+use Drupal\Core\Url;
+
+/**
+ * Provides a form for deleting a feed.
+ */
+class FeedDeleteForm extends ContentEntityDeleteForm {
+
+  /**
+   * {@inheritdoc}
+   */
+  public function getCancelUrl() {
+    return new Url('aggregator.admin_overview');
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  protected function getRedirectUrl() {
+    return $this->getCancelUrl();
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  protected function getDeletionMessage() {
+    return $this->t('The feed %label has been deleted.', array(
+      '%label' => $this->entity->label(),
+    ));
+  }
+
+}

core/modules/aggregator/src/Form/FeedItemsDeleteForm.php

@@ -0,0 +1,49 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\aggregator\Form\FeedItemsDeleteForm.
+ */
+
+namespace Drupal\aggregator\Form;
+
+use Drupal\Core\Entity\ContentEntityConfirmFormBase;
+use Drupal\Core\Form\FormStateInterface;
+use Drupal\Core\Url;
+
+/**
+ * Provides a deletion confirmation form for items that belong to a feed.
+ */
+class FeedItemsDeleteForm extends ContentEntityConfirmFormBase {
+
+  /**
+   * {@inheritdoc}
+   */
+  public function getQuestion() {
+    return $this->t('Are you sure you want to delete all items from the feed %feed?', array('%feed' => $this->entity->label()));
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function getCancelUrl() {
+    return new Url('aggregator.admin_overview');
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function getConfirmText() {
+    return $this->t('Delete items');
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function submitForm(array &$form, FormStateInterface $form_state) {
+    $this->entity->deleteItems();
+
+    $form_state->setRedirectUrl($this->getCancelUrl());
+  }
+
+}

core/modules/aggregator/src/Form/OpmlFeedAdd.php

@@ -0,0 +1,214 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\aggregator\Form\OpmlFeedAdd.
+ */
+
+namespace Drupal\aggregator\Form;
+
+use Drupal\aggregator\FeedStorageInterface;
+use Drupal\Component\Utility\UrlHelper;
+use Drupal\Core\Form\FormBase;
+use Drupal\Core\Form\FormStateInterface;
+use Symfony\Component\DependencyInjection\ContainerInterface;
+use GuzzleHttp\Exception\RequestException;
+use GuzzleHttp\ClientInterface;
+
+/**
+ * Imports feeds from OPML.
+ */
+class OpmlFeedAdd extends FormBase {
+
+  /**
+   * The feed storage.
+   *
+   * @var \Drupal\aggregator\FeedStorageInterface
+   */
+  protected $feedStorage;
+
+  /**
+   * The HTTP client to fetch the feed data with.
+   *
+   * @var \GuzzleHttp\ClientInterface
+   */
+  protected $httpClient;
+
+  /**
+   * Constructs a database object.
+   *
+   * @param \Drupal\aggregator\FeedStorageInterface $feed_storage
+   *   The feed storage.
+   * @param \GuzzleHttp\ClientInterface $http_client
+   *   The Guzzle HTTP client.
+   */
+  public function __construct(FeedStorageInterface $feed_storage, ClientInterface $http_client) {
+    $this->feedStorage = $feed_storage;
+    $this->httpClient = $http_client;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public static function create(ContainerInterface $container) {
+    return new static(
+      $container->get('entity.manager')->getStorage('aggregator_feed'),
+      $container->get('http_client')
+    );
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function getFormId() {
+    return 'aggregator_opml_add';
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function buildForm(array $form, FormStateInterface $form_state) {
+    $intervals = array(900, 1800, 3600, 7200, 10800, 21600, 32400, 43200, 64800, 86400, 172800, 259200, 604800, 1209600, 2419200);
+    $period = array_map(array(\Drupal::service('date.formatter'), 'formatInterval'), array_combine($intervals, $intervals));
+
+    $form['upload'] = array(
+      '#type' => 'file',
+      '#title' => $this->t('OPML File'),
+      '#description' => $this->t('Upload an OPML file containing a list of feeds to be imported.'),
+    );
+    $form['remote'] = array(
+      '#type' => 'url',
+      '#title' => $this->t('OPML Remote URL'),
+      '#maxlength' => 1024,
+      '#description' => $this->t('Enter the URL of an OPML file. This file will be downloaded and processed only once on submission of the form.'),
+    );
+    $form['refresh'] = array(
+      '#type' => 'select',
+      '#title' => $this->t('Update interval'),
+      '#default_value' => 3600,
+      '#options' => $period,
+      '#description' => $this->t('The length of time between feed updates. Requires a correctly configured <a href="@cron">cron maintenance task</a>.', array('@cron' => $this->url('system.status'))),
+    );
+
+    $form['actions'] = array('#type' => 'actions');
+    $form['actions']['submit'] = array(
+      '#type' => 'submit',
+      '#value' => $this->t('Import'),
+    );
+
+    return $form;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function validateForm(array &$form, FormStateInterface $form_state) {
+    // If both fields are empty or filled, cancel.
+    $file_upload = $this->getRequest()->files->get('files[upload]', NULL, TRUE);
+    if ($form_state->isValueEmpty('remote') == empty($file_upload)) {
+      $form_state->setErrorByName('remote', $this->t('<em>Either</em> upload a file or enter a URL.'));
+    }
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function submitForm(array &$form, FormStateInterface $form_state) {
+    $validators = array('file_validate_extensions' => array('opml xml'));
+    if ($file = file_save_upload('upload', $validators, FALSE, 0)) {
+      $data = file_get_contents($file->getFileUri());
+    }
+    else {
+      // @todo Move this to a fetcher implementation.
+      try {
+        $response = $this->httpClient->get($form_state->getValue('remote'));
+        $data = $response->getBody(TRUE);
+      }
+      catch (RequestException $e) {
+        $this->logger('aggregator')->warning('Failed to download OPML file due to "%error".', array('%error' => $e->getMessage()));
+        drupal_set_message($this->t('Failed to download OPML file due to "%error".', array('%error' => $e->getMessage())));
+        return;
+      }
+    }
+
+    $feeds = $this->parseOpml($data);
+    if (empty($feeds)) {
+      drupal_set_message($this->t('No new feed has been added.'));
+      return;
+    }
+
+    // @todo Move this functionality to a processor.
+    foreach ($feeds as $feed) {
+      // Ensure URL is valid.
+      if (!UrlHelper::isValid($feed['url'], TRUE)) {
+        drupal_set_message($this->t('The URL %url is invalid.', array('%url' => $feed['url'])), 'warning');
+        continue;
+      }
+
+      // Check for duplicate titles or URLs.
+      $query = $this->feedStorage->getQuery();
+      $condition = $query->orConditionGroup()
+        ->condition('title', $feed['title'])
+        ->condition('url', $feed['url']);
+      $ids = $query
+        ->condition($condition)
+        ->execute();
+      $result = $this->feedStorage->loadMultiple($ids);
+      foreach ($result as $old) {
+        if (strcasecmp($old->label(), $feed['title']) == 0) {
+          drupal_set_message($this->t('A feed named %title already exists.', array('%title' => $old->label())), 'warning');
+          continue 2;
+        }
+        if (strcasecmp($old->getUrl(), $feed['url']) == 0) {
+          drupal_set_message($this->t('A feed with the URL %url already exists.', array('%url' => $old->getUrl())), 'warning');
+          continue 2;
+        }
+      }
+
+      $new_feed = $this->feedStorage->create(array(
+        'title' => $feed['title'],
+        'url' => $feed['url'],
+        'refresh' => $form_state->getValue('refresh'),
+      ));
+      $new_feed->save();
+    }
+
+    $form_state->setRedirect('aggregator.admin_overview');
+  }
+
+  /**
+   * Parses an OPML file.
+   *
+   * Feeds are recognized as <outline> elements with the attributes "text" and
+   * "xmlurl" set.
+   *
+   * @param string $opml
+   *   The complete contents of an OPML document.
+   *
+   * @return array
+   *   An array of feeds, each an associative array with a "title" and a "url"
+   *   element, or NULL if the OPML document failed to be parsed. An empty array
+   *   will be returned if the document is valid but contains no feeds, as some
+   *   OPML documents do.
+   *
+   * @todo Move this to a parser in https://www.drupal.org/node/1963540.
+   */
+  protected function parseOpml($opml) {
+    $feeds = array();
+    $xml_parser = drupal_xml_parser_create($opml);
+    if (xml_parse_into_struct($xml_parser, $opml, $values)) {
+      foreach ($values as $entry) {
+        if ($entry['tag'] == 'OUTLINE' && isset($entry['attributes'])) {
+          $item = $entry['attributes'];
+          if (!empty($item['XMLURL']) && !empty($item['TEXT'])) {
+            $feeds[] = array('title' => $item['TEXT'], 'url' => $item['XMLURL']);
+          }
+        }
+      }
+    }
+    xml_parser_free($xml_parser);
+
+    return $feeds;
+  }
+
+}

core/modules/aggregator/src/Form/SettingsForm.php

@@ -0,0 +1,230 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\aggregator\Form\SettingsForm.
+ */
+
+namespace Drupal\aggregator\Form;
+
+use Drupal\aggregator\Plugin\AggregatorPluginManager;
+use Drupal\Component\Utility\SafeMarkup;
+use Drupal\Core\Config\ConfigFactoryInterface;
+use Drupal\Core\Form\FormStateInterface;
+use Drupal\Core\Plugin\PluginFormInterface;
+use Drupal\Core\StringTranslation\TranslationInterface;
+use Drupal\Core\Form\ConfigFormBase;
+use Symfony\Component\DependencyInjection\ContainerInterface;
+
+/**
+ * Configures aggregator settings for this site.
+ */
+class SettingsForm extends ConfigFormBase {
+
+  /**
+   * The aggregator plugin managers.
+   *
+   * @var \Drupal\aggregator\Plugin\AggregatorPluginManager[]
+   */
+  protected $managers = array();
+
+  /**
+   * The instantiated plugin instances that have configuration forms.
+   *
+   * @var \Drupal\Core\Plugin\PluginFormInterface[]
+   */
+  protected $configurableInstances = array();
+
+  /**
+   * The aggregator plugin definitions.
+   *
+   * @var array
+   */
+  protected $definitions = array(
+    'fetcher' => array(),
+    'parser' => array(),
+    'processor' => array(),
+  );
+
+  /**
+   * Constructs a \Drupal\aggregator\SettingsForm object.
+   *
+   * @param \Drupal\Core\Config\ConfigFactoryInterface $config_factory
+   *   The factory for configuration objects.
+   * @param \Drupal\aggregator\Plugin\AggregatorPluginManager $fetcher_manager
+   *   The aggregator fetcher plugin manager.
+   * @param \Drupal\aggregator\Plugin\AggregatorPluginManager $parser_manager
+   *   The aggregator parser plugin manager.
+   * @param \Drupal\aggregator\Plugin\AggregatorPluginManager $processor_manager
+   *   The aggregator processor plugin manager.
+   * @param \Drupal\Core\StringTranslation\TranslationInterface $string_translation
+   *   The string translation manager.
+   */
+  public function __construct(ConfigFactoryInterface $config_factory, AggregatorPluginManager $fetcher_manager, AggregatorPluginManager $parser_manager, AggregatorPluginManager $processor_manager, TranslationInterface $string_translation) {
+    parent::__construct($config_factory);
+    $this->stringTranslation = $string_translation;
+    $this->managers = array(
+      'fetcher' => $fetcher_manager,
+      'parser' => $parser_manager,
+      'processor' => $processor_manager,
+    );
+    // Get all available fetcher, parser and processor definitions.
+    foreach (array('fetcher', 'parser', 'processor') as $type) {
+      foreach ($this->managers[$type]->getDefinitions() as $id => $definition) {
+        $this->definitions[$type][$id] = SafeMarkup::format('@title <span class="description">@description</span>', array('@title' => $definition['title'], '@description' => $definition['description']));
+      }
+    }
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public static function create(ContainerInterface $container) {
+    return new static(
+      $container->get('config.factory'),
+      $container->get('plugin.manager.aggregator.fetcher'),
+      $container->get('plugin.manager.aggregator.parser'),
+      $container->get('plugin.manager.aggregator.processor'),
+      $container->get('string_translation')
+    );
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function getFormId() {
+    return 'aggregator_admin_form';
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  protected function getEditableConfigNames() {
+    return ['aggregator.settings'];
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function buildForm(array $form, FormStateInterface $form_state) {
+    $config = $this->config('aggregator.settings');
+
+    // Global aggregator settings.
+    $form['aggregator_allowed_html_tags'] = array(
+      '#type' => 'textfield',
+      '#title' => $this->t('Allowed HTML tags'),
+      '#size' => 80,
+      '#maxlength' => 255,
+      '#default_value' => $config->get('items.allowed_html'),
+      '#description' => $this->t('A space-separated list of HTML tags allowed in the content of feed items. Disallowed tags are stripped from the content.'),
+    );
+
+    // Only show basic configuration if there are actually options.
+    $basic_conf = array();
+    if (count($this->definitions['fetcher']) > 1) {
+      $basic_conf['aggregator_fetcher'] = array(
+        '#type' => 'radios',
+        '#title' => $this->t('Fetcher'),
+        '#description' => $this->t('Fetchers download data from an external source. Choose a fetcher suitable for the external source you would like to download from.'),
+        '#options' => $this->definitions['fetcher'],
+        '#default_value' => $config->get('fetcher'),
+      );
+    }
+    if (count($this->definitions['parser']) > 1) {
+      $basic_conf['aggregator_parser'] = array(
+        '#type' => 'radios',
+        '#title' => $this->t('Parser'),
+        '#description' => $this->t('Parsers transform downloaded data into standard structures. Choose a parser suitable for the type of feeds you would like to aggregate.'),
+        '#options' => $this->definitions['parser'],
+        '#default_value' => $config->get('parser'),
+      );
+    }
+    if (count($this->definitions['processor']) > 1) {
+      $basic_conf['aggregator_processors'] = array(
+        '#type' => 'checkboxes',
+        '#title' => $this->t('Processors'),
+        '#description' => $this->t('Processors act on parsed feed data, for example they store feed items. Choose the processors suitable for your task.'),
+        '#options' => $this->definitions['processor'],
+        '#default_value' => $config->get('processors'),
+      );
+    }
+    if (count($basic_conf)) {
+      $form['basic_conf'] = array(
+        '#type' => 'details',
+        '#title' => $this->t('Basic configuration'),
+        '#description' => $this->t('For most aggregation tasks, the default settings are fine.'),
+        '#open' => TRUE,
+      );
+      $form['basic_conf'] += $basic_conf;
+    }
+
+    // Call buildConfigurationForm() on the active fetcher and parser.
+    foreach (array('fetcher', 'parser') as $type) {
+      $active = $config->get($type);
+      if (array_key_exists($active, $this->definitions[$type])) {
+        $instance = $this->managers[$type]->createInstance($active);
+        if ($instance instanceof PluginFormInterface) {
+          $form = $instance->buildConfigurationForm($form, $form_state);
+          // Store the instance for validate and submit handlers.
+          // Keying by ID would bring conflicts, because two instances of a
+          // different type could have the same ID.
+          $this->configurableInstances[] = $instance;
+        }
+      }
+    }
+
+    // Implementing processor plugins will expect an array at $form['processors'].
+    $form['processors'] = array();
+    // Call buildConfigurationForm() for each active processor.
+    foreach ($this->definitions['processor'] as $id => $definition) {
+      if (in_array($id, $config->get('processors'))) {
+        $instance = $this->managers['processor']->createInstance($id);
+        if ($instance instanceof PluginFormInterface) {
+          $form = $instance->buildConfigurationForm($form, $form_state);
+          // Store the instance for validate and submit handlers.
+          // Keying by ID would bring conflicts, because two instances of a
+          // different type could have the same ID.
+          $this->configurableInstances[] = $instance;
+        }
+      }
+    }
+
+    return parent::buildForm($form, $form_state);
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function validateForm(array &$form, FormStateInterface $form_state) {
+    parent::validateForm($form, $form_state);
+    // Let active plugins validate their settings.
+    foreach ($this->configurableInstances as $instance) {
+      $instance->validateConfigurationForm($form, $form_state);
+    }
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function submitForm(array &$form, FormStateInterface $form_state) {
+    parent::submitForm($form, $form_state);
+    $config = $this->config('aggregator.settings');
+    // Let active plugins save their settings.
+    foreach ($this->configurableInstances as $instance) {
+      $instance->submitConfigurationForm($form, $form_state);
+    }
+
+    $config->set('items.allowed_html', $form_state->getValue('aggregator_allowed_html_tags'));
+    if ($form_state->hasValue('aggregator_fetcher')) {
+      $config->set('fetcher', $form_state->getValue('aggregator_fetcher'));
+    }
+    if ($form_state->hasValue('aggregator_parser')) {
+      $config->set('parser', $form_state->getValue('aggregator_parser'));
+    }
+    if ($form_state->hasValue('aggregator_processors')) {
+      $config->set('processors', array_filter($form_state->getValue('aggregator_processors')));
+    }
+    $config->save();
+  }
+
+}

core/modules/aggregator/src/ItemInterface.php

@@ -0,0 +1,149 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\aggregator\ItemInterface.
+ */
+
+namespace Drupal\aggregator;
+
+use Drupal\Core\Entity\ContentEntityInterface;
+
+/**
+ * Provides an interface defining an aggregator item entity.
+ */
+interface ItemInterface extends ContentEntityInterface {
+
+  /**
+   * Returns the feed id of aggregator item.
+   *
+   * @return int
+   *   The feed id.
+   */
+  public function getFeedId();
+
+  /**
+   * Sets the feed id of aggregator item.
+   *
+   * @param int $fid
+   *   The feed id.
+   *
+   * @return \Drupal\aggregator\ItemInterface
+   *   The called feed item entity.
+   */
+  public function setFeedId($fid);
+
+  /**
+   * Returns the title of the feed item.
+   *
+   * @return string
+   *   The title of the feed item.
+   */
+  public function getTitle();
+
+  /**
+   * Sets the title of the feed item.
+   *
+   * @param string $title
+   *   The title of the feed item.
+   *
+   * @return \Drupal\aggregator\ItemInterface
+   *   The called feed item entity.
+   */
+  public function setTitle($title);
+
+  /**
+   * Returns the link to the feed item.
+   *
+   * @return string
+   *   The link to the feed item.
+   */
+  public function getLink();
+
+  /**
+   * Sets the link to the feed item.
+   *
+   * @param string $link
+   *   The link to the feed item.
+   *
+   * @return \Drupal\aggregator\ItemInterface
+   *   The called feed item entity.
+   */
+  public function setLink($link);
+
+  /**
+   * Returns the author of the feed item.
+   *
+   * @return string
+   *   The author of the feed item.
+   */
+  public function getAuthor();
+
+  /**
+   * Sets the author of the feed item.
+   *
+   * @param string $author
+   *   The author name of the feed item.
+   *
+   * @return \Drupal\aggregator\ItemInterface
+   *   The called feed item entity.
+   */
+  public function setAuthor($author);
+
+  /**
+   * Returns the body of the feed item.
+   *
+   * @return string
+   *   The body of the feed item.
+   */
+  public function getDescription();
+
+  /**
+   * Sets the body of the feed item.
+   *
+   * @param string $description
+   *   The body of the feed item.
+   *
+   * @return \Drupal\aggregator\ItemInterface
+   *   The called feed item entity.
+   */
+  public function setDescription($description);
+
+  /**
+   * Returns the posted date of the feed item, as a Unix timestamp.
+   *
+   * @return int
+   *   The posted date of the feed item, as a Unix timestamp.
+   */
+  public function getPostedTime();
+
+  /**
+   * Sets the posted date of the feed item, as a Unix timestamp.
+   *
+   * @param int $timestamp
+   *   The posted date of the feed item, as a Unix timestamp.
+   *
+   * @return \Drupal\aggregator\ItemInterface
+   *   The called feed item entity.
+   */
+  public function setPostedTime($timestamp);
+
+  /**
+   * Returns the unique identifier for the feed item.
+   *
+   * @return string
+   *   The unique identifier for the feed item.
+   */
+  public function getGuid();
+
+  /**
+   * Sets the unique identifier for the feed item.
+   *
+   * @param string $guid
+   *   The unique identifier for the feed item.
+   *
+   * @return \Drupal\aggregator\ItemInterface
+   *   The called feed item entity.
+   */
+  public function setGuid($guid);
+}

core/modules/aggregator/src/ItemStorage.php

@@ -0,0 +1,70 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\aggregator\ItemStorage.
+ */
+
+namespace Drupal\aggregator;
+
+use Drupal\Core\Entity\Query\QueryInterface;
+use Drupal\Core\Entity\Sql\SqlContentEntityStorage;
+
+/**
+ * Controller class for aggregators items.
+ *
+ * This extends the Drupal\Core\Entity\Sql\SqlContentEntityStorage class, adding
+ * required special handling for feed item entities.
+ */
+class ItemStorage extends SqlContentEntityStorage implements ItemStorageInterface {
+
+  /**
+   * {@inheritdoc}
+   */
+  public function getItemCount(FeedInterface $feed) {
+    $query = \Drupal::entityQuery('aggregator_item')
+      ->condition('fid', $feed->id())
+      ->count();
+
+    return $query->execute();
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function loadAll($limit = NULL) {
+    $query = \Drupal::entityQuery('aggregator_item');
+    return $this->executeFeedItemQuery($query, $limit);
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function loadByFeed($fid, $limit = NULL) {
+    $query = \Drupal::entityQuery('aggregator_item')
+      ->condition('fid', $fid);
+    return $this->executeFeedItemQuery($query, $limit);
+  }
+
+  /**
+   * Helper method to execute an item query.
+   *
+   * @param \Drupal\Core\Entity\Query\QueryInterface $query
+   *   The query to execute.
+   * @param int $limit
+   *   (optional) The number of items to return.
+   *
+   * @return \Drupal\aggregator\ItemInterface[]
+   *   An array of the feed items.
+   */
+  protected function executeFeedItemQuery(QueryInterface $query, $limit) {
+    $query->sort('timestamp', 'DESC')
+      ->sort('iid', 'DESC');
+    if (!empty($limit)) {
+      $query->pager($limit);
+    }
+
+    return $this->loadMultiple($query->execute());
+  }
+
+}

core/modules/aggregator/src/ItemStorageInterface.php

@@ -0,0 +1,53 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\aggregator\ItemStorageInterface.
+ */
+
+namespace Drupal\aggregator;
+
+use Drupal\aggregator\Entity\Item;
+use Drupal\Core\Entity\EntityStorageInterface;
+
+/**
+ * Defines an interface for aggregator item entity storage classes.
+ */
+interface ItemStorageInterface extends EntityStorageInterface {
+
+  /**
+   * Returns the count of the items in a feed.
+   *
+   * @param \Drupal\aggregator\FeedInterface $feed
+   *   The feed entity.
+   *
+   * @return int
+   *   The count of items associated with a feed.
+   */
+  public function getItemCount(FeedInterface $feed);
+
+  /**
+   * Loads feed items from all feeds.
+   *
+   * @param int $limit
+   *   (optional) The number of items to return. Defaults to unlimited.
+   *
+   * @return \Drupal\aggregator\ItemInterface[]
+   *   An array of the feed items.
+   */
+  public function loadAll($limit = NULL);
+
+  /**
+   * Loads feed items filtered by a feed.
+   *
+   * @param int $fid
+   *   The feed ID to filter by.
+   * @param int $limit
+   *   (optional) The number of items to return. Defaults to unlimited.
+   *
+   * @return \Drupal\aggregator\ItemInterface[]
+   *   An array of the feed items.
+   */
+  public function loadByFeed($fid, $limit = NULL);
+
+}

core/modules/aggregator/src/ItemStorageSchema.php

@@ -0,0 +1,41 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\aggregator\ItemStorageSchema.
+ */
+
+namespace Drupal\aggregator;
+
+use Drupal\Core\Entity\ContentEntityTypeInterface;
+use Drupal\Core\Entity\Sql\SqlContentEntityStorageSchema;
+use Drupal\Core\Field\FieldStorageDefinitionInterface;
+
+/**
+ * Defines the item schema handler.
+ */
+class ItemStorageSchema extends SqlContentEntityStorageSchema {
+
+  /**
+   * {@inheritdoc}
+   */
+  protected function getSharedTableFieldSchema(FieldStorageDefinitionInterface $storage_definition, $table_name, array $column_mapping) {
+    $schema = parent::getSharedTableFieldSchema($storage_definition, $table_name, $column_mapping);
+    $field_name = $storage_definition->getName();
+
+    if ($table_name == 'aggregator_item') {
+      switch ($field_name) {
+        case 'timestamp':
+          $this->addSharedTableFieldIndex($storage_definition, $schema, TRUE);
+          break;
+
+        case 'fid':
+          $this->addSharedTableFieldForeignKey($storage_definition, $schema, 'aggregator_feed', 'fid');
+          break;
+      }
+    }
+
+    return $schema;
+  }
+
+}

core/modules/aggregator/src/ItemViewBuilder.php

@@ -0,0 +1,37 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\aggregator\ItemViewBuilder.
+ */
+
+namespace Drupal\aggregator;
+
+use Drupal\Core\Entity\EntityViewBuilder;
+
+/**
+ * Render controller for aggregator feed items.
+ */
+class ItemViewBuilder extends EntityViewBuilder {
+
+  /**
+   * {@inheritdoc}
+   */
+  public function buildComponents(array &$build, array $entities, array $displays, $view_mode, $langcode = NULL) {
+    parent::buildComponents($build, $entities, $displays, $view_mode, $langcode);
+
+    foreach ($entities as $id => $entity) {
+      $bundle = $entity->bundle();
+      $display = $displays[$bundle];
+
+      if ($display->getComponent('description')) {
+        $build[$id]['description'] = array(
+          '#markup' => aggregator_filter_xss($entity->getDescription()),
+          '#prefix' => '<div class="item-description">',
+          '#suffix' => '</div>',
+        );
+      }
+    }
+  }
+
+}

core/modules/aggregator/src/ItemsImporter.php

@@ -0,0 +1,158 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\aggregator\ItemsImporter.
+ */
+
+namespace Drupal\aggregator;
+
+use Drupal\aggregator\Plugin\AggregatorPluginManager;
+use Drupal\Component\Plugin\Exception\PluginException;
+use Drupal\Core\Config\ConfigFactoryInterface;
+use Psr\Log\LoggerInterface;
+
+/**
+ * Defines an importer of aggregator items.
+ */
+class ItemsImporter implements ItemsImporterInterface {
+
+  /**
+   * The aggregator fetcher manager.
+   *
+   * @var \Drupal\aggregator\Plugin\AggregatorPluginManager
+   */
+  protected $fetcherManager;
+
+  /**
+   * The aggregator processor manager.
+   *
+   * @var \Drupal\aggregator\Plugin\AggregatorPluginManager
+   */
+  protected $processorManager;
+
+  /**
+   * The aggregator parser manager.
+   *
+   * @var \Drupal\aggregator\Plugin\AggregatorPluginManager
+   */
+  protected $parserManager;
+
+  /**
+   * The aggregator.settings config object.
+   *
+   * @var \Drupal\Core\Config\Config
+   */
+  protected $config;
+
+  /**
+   * A logger instance.
+   *
+   * @var \Psr\Log\LoggerInterface
+   */
+  protected $logger;
+
+  /**
+   * Constructs an Importer object.
+   *
+   * @param \Drupal\Core\Config\ConfigFactoryInterface $config_factory
+   *   The factory for configuration objects.
+   * @param \Drupal\aggregator\Plugin\AggregatorPluginManager $fetcher_manager
+   *   The aggregator fetcher plugin manager.
+   * @param \Drupal\aggregator\Plugin\AggregatorPluginManager $parser_manager
+   *   The aggregator parser plugin manager.
+   * @param \Drupal\aggregator\Plugin\AggregatorPluginManager $processor_manager
+   *   The aggregator processor plugin manager.
+   * @param \Psr\Log\LoggerInterface $logger
+   *   A logger instance.
+   */
+  public function __construct(ConfigFactoryInterface $config_factory, AggregatorPluginManager $fetcher_manager, AggregatorPluginManager $parser_manager, AggregatorPluginManager $processor_manager, LoggerInterface $logger) {
+    $this->fetcherManager = $fetcher_manager;
+    $this->processorManager = $processor_manager;
+    $this->parserManager = $parser_manager;
+    $this->config = $config_factory->get('aggregator.settings');
+    $this->logger = $logger;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function delete(FeedInterface $feed) {
+    foreach ($this->processorManager->getDefinitions() as $id => $definition) {
+      $this->processorManager->createInstance($id)->delete($feed);
+    }
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function refresh(FeedInterface $feed) {
+    // Store feed URL to track changes.
+    $feed_url = $feed->getUrl();
+
+    // Fetch the feed.
+    try {
+      $success = $this->fetcherManager->createInstance($this->config->get('fetcher'))->fetch($feed);
+    }
+    catch (PluginException $e) {
+      $success = FALSE;
+      watchdog_exception('aggregator', $e);
+    }
+
+    // Store instances in an array so we dont have to instantiate new objects.
+    $processor_instances = array();
+    foreach ($this->config->get('processors') as $processor) {
+      try {
+        $processor_instances[$processor] = $this->processorManager->createInstance($processor);
+      }
+      catch (PluginException $e) {
+        watchdog_exception('aggregator', $e);
+      }
+    }
+
+    // We store the hash of feed data in the database. When refreshing a
+    // feed we compare stored hash and new hash calculated from downloaded
+    // data. If both are equal we say that feed is not updated.
+    $hash = hash('sha256', $feed->source_string);
+    $has_new_content = $success && ($feed->getHash() != $hash);
+
+    if ($has_new_content) {
+      // Parse the feed.
+      try {
+        if ($this->parserManager->createInstance($this->config->get('parser'))->parse($feed)) {
+          if (!$feed->getWebsiteUrl()) {
+            $feed->setWebsiteUrl($feed->getUrl());
+          }
+          $feed->setHash($hash);
+          // Update feed with parsed data.
+          $feed->save();
+
+          // Log if feed URL has changed.
+          if ($feed->getUrl() != $feed_url) {
+            $this->logger->notice('Updated URL for feed %title to %url.', array('%title' => $feed->label(), '%url' => $feed->getUrl()));
+          }
+
+          $this->logger->notice('There is new syndicated content from %site.', array('%site' => $feed->label()));
+
+          // If there are items on the feed, let enabled processors process them.
+          if (!empty($feed->items)) {
+            foreach ($processor_instances as $instance) {
+              $instance->process($feed);
+            }
+          }
+        }
+      }
+      catch (PluginException $e) {
+        watchdog_exception('aggregator', $e);
+      }
+    }
+
+    // Processing is done, call postProcess on enabled processors.
+    foreach ($processor_instances as $instance) {
+      $instance->postProcess($feed);
+    }
+
+    return $has_new_content;
+  }
+
+}

core/modules/aggregator/src/ItemsImporterInterface.php

@@ -0,0 +1,37 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\aggregator\ItemsImporterInterface.
+ */
+
+namespace Drupal\aggregator;
+
+/**
+ * Provides an interface defining an aggregator items importer.
+ */
+interface ItemsImporterInterface {
+
+  /**
+   * Updates the feed items by triggering the import process.
+   *
+   * This process can be slow and lengthy because it relies on network
+   * operations. Calling it on performance critical paths should be avoided.
+   *
+   * @param \Drupal\aggregator\FeedInterface $feed
+   *   The feed which items should be refreshed.
+   *
+   * @return bool
+   *   TRUE if there is new content for the feed FALSE otherwise.
+   */
+  public function refresh(FeedInterface $feed);
+
+  /**
+   * Deletes all imported items from a feed.
+   *
+   * @param \Drupal\aggregator\FeedInterface $feed
+   *   The feed that associated items should be deleted from.
+   */
+  public function delete(FeedInterface $feed);
+
+}

core/modules/aggregator/src/Plugin/AggregatorPluginManager.php

@@ -0,0 +1,57 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\aggregator\Plugin\AggregatorPluginManager.
+ */
+
+namespace Drupal\aggregator\Plugin;
+
+use Drupal\Core\Cache\CacheBackendInterface;
+use Drupal\Core\Extension\ModuleHandlerInterface;
+use Drupal\Core\Plugin\DefaultPluginManager;
+
+/**
+ * Manages aggregator plugins.
+ *
+ * @see \Drupal\aggregator\Annotation\AggregatorParser
+ * @see \Drupal\aggregator\Annotation\AggregatorFetcher
+ * @see \Drupal\aggregator\Annotation\AggregatorProcessor
+ * @see \Drupal\aggregator\Plugin\AggregatorPluginSettingsBase
+ * @see \Drupal\aggregator\Plugin\FetcherInterface
+ * @see \Drupal\aggregator\Plugin\ProcessorInterface
+ * @see \Drupal\aggregator\Plugin\ParserInterface
+ * @see plugin_api
+ */
+class AggregatorPluginManager extends DefaultPluginManager {
+
+  /**
+   * Constructs a AggregatorPluginManager object.
+   *
+   * @param string $type
+   *   The plugin type, for example fetcher.
+   * @param \Traversable $namespaces
+   *   An object that implements \Traversable which contains the root paths
+   *   keyed by the corresponding namespace to look for plugin implementations.
+   * @param \Drupal\Core\Cache\CacheBackendInterface $cache_backend
+   *   Cache backend instance to use.
+   * @param \Drupal\Core\Extension\ModuleHandlerInterface $module_handler
+   *   The module handler.
+   */
+  public function __construct($type, \Traversable $namespaces, CacheBackendInterface $cache_backend, ModuleHandlerInterface $module_handler) {
+    $type_annotations = array(
+      'fetcher' => 'Drupal\aggregator\Annotation\AggregatorFetcher',
+      'parser' => 'Drupal\aggregator\Annotation\AggregatorParser',
+      'processor' => 'Drupal\aggregator\Annotation\AggregatorProcessor',
+    );
+    $plugin_interfaces = array(
+      'fetcher' => 'Drupal\aggregator\Plugin\FetcherInterface',
+      'parser' => 'Drupal\aggregator\Plugin\ParserInterface',
+      'processor' => 'Drupal\aggregator\Plugin\ProcessorInterface',
+    );
+
+    parent::__construct("Plugin/aggregator/$type", $namespaces, $module_handler, $plugin_interfaces[$type], $type_annotations[$type]);
+    $this->setCacheBackend($cache_backend, 'aggregator_' . $type . '_plugins');
+  }
+
+}

core/modules/aggregator/src/Plugin/AggregatorPluginSettingsBase.php

@@ -0,0 +1,49 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\aggregator\Plugin\AggregatorPluginSettingsBase.
+ */
+
+namespace Drupal\aggregator\Plugin;
+
+use Drupal\Component\Plugin\ConfigurablePluginInterface;
+use Drupal\Core\Form\FormStateInterface;
+use Drupal\Core\Plugin\PluginBase;
+use Drupal\Core\Plugin\PluginFormInterface;
+
+/**
+ * Base class for aggregator plugins that implement settings forms.
+ *
+ * @see \Drupal\aggregator\Annotation\AggregatorParser
+ * @see \Drupal\aggregator\Annotation\AggregatorFetcher
+ * @see \Drupal\aggregator\Annotation\AggregatorProcessor
+ * @see \Drupal\aggregator\Plugin\AggregatorPluginManager
+ * @see \Drupal\aggregator\Plugin\FetcherInterface
+ * @see \Drupal\aggregator\Plugin\ProcessorInterface
+ * @see \Drupal\aggregator\Plugin\ParserInterface
+ * @see plugin_api
+ */
+abstract class AggregatorPluginSettingsBase extends PluginBase implements PluginFormInterface, ConfigurablePluginInterface {
+
+  /**
+   * {@inheritdoc}
+   */
+  public function defaultConfiguration() {
+    return array();
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function validateConfigurationForm(array &$form, FormStateInterface $form_state) {
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function calculateDependencies() {
+    return array();
+  }
+
+}

core/modules/aggregator/src/Plugin/Block/AggregatorFeedBlock.php

@@ -0,0 +1,196 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\aggregator\Plugin\Block\AggregatorFeedBlock.
+ */
+
+namespace Drupal\aggregator\Plugin\Block;
+
+use Drupal\aggregator\FeedStorageInterface;
+use Drupal\aggregator\ItemStorageInterface;
+use Drupal\Core\Access\AccessResult;
+use Drupal\Core\Block\BlockBase;
+use Drupal\Core\Cache\Cache;
+use Drupal\Core\Entity\Query\QueryInterface;
+use Drupal\Core\Form\FormStateInterface;
+use Drupal\Core\Plugin\ContainerFactoryPluginInterface;
+use Drupal\Core\Session\AccountInterface;
+use Symfony\Component\DependencyInjection\ContainerInterface;
+
+/**
+ * Provides an 'Aggregator feed' block with the latest items from the feed.
+ *
+ * @Block(
+ *   id = "aggregator_feed_block",
+ *   admin_label = @Translation("Aggregator feed"),
+ *   category = @Translation("Lists (Views)")
+ * )
+ */
+class AggregatorFeedBlock extends BlockBase implements ContainerFactoryPluginInterface {
+
+  /**
+   * The entity storage for feeds.
+   *
+   * @var \Drupal\aggregator\FeedStorageInterface
+   */
+  protected $feedStorage;
+
+  /**
+   * The entity storage for items.
+   *
+   * @var \Drupal\aggregator\ItemStorageInterface
+   */
+  protected $itemStorage;
+
+  /**
+   * The entity query object for feed items.
+   *
+   * @var \Drupal\Core\Entity\Query\QueryInterface
+   */
+  protected $itemQuery;
+
+  /**
+   * Constructs an AggregatorFeedBlock object.
+   *
+   * @param array $configuration
+   *   A configuration array containing information about the plugin instance.
+   * @param string $plugin_id
+   *   The plugin_id for the plugin instance.
+   * @param mixed $plugin_definition
+   *   The plugin implementation definition.
+   * @param \Drupal\aggregator\FeedStorageInterface $feed_storage
+   *   The entity storage for feeds.
+   * @param \Drupal\aggregator\ItemStorageInterface $item_storage
+   *   The entity storage for feed items.
+   * @param \Drupal\Core\Entity\Query\QueryInterface $item_query
+   *   The entity query object for feed items.
+   */
+  public function __construct(array $configuration, $plugin_id, $plugin_definition, FeedStorageInterface $feed_storage, ItemStorageInterface $item_storage, QueryInterface $item_query) {
+    parent::__construct($configuration, $plugin_id, $plugin_definition);
+    $this->feedStorage = $feed_storage;
+    $this->itemStorage = $item_storage;
+    $this->itemQuery = $item_query;
+  }
+
+
+  /**
+   * {@inheritdoc}
+   */
+  public static function create(ContainerInterface $container, array $configuration, $plugin_id, $plugin_definition) {
+    return new static(
+      $configuration,
+      $plugin_id,
+      $plugin_definition,
+      $container->get('entity.manager')->getStorage('aggregator_feed'),
+      $container->get('entity.manager')->getStorage('aggregator_item'),
+      $container->get('entity.query')->get('aggregator_item')
+    );
+  }
+
+
+  /**
+   * {@inheritdoc}
+   */
+  public function defaultConfiguration() {
+    // By default, the block will contain 10 feed items.
+    return array(
+      'block_count' => 10,
+      'feed' => NULL,
+    );
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  protected function blockAccess(AccountInterface $account) {
+    // Only grant access to users with the 'access news feeds' permission.
+    return AccessResult::allowedIfHasPermission($account, 'access news feeds');
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function blockForm($form, FormStateInterface $form_state) {
+    $feeds = $this->feedStorage->loadMultiple();
+    $options = array();
+    foreach ($feeds as $feed) {
+      $options[$feed->id()] = $feed->label();
+    }
+    $form['feed'] = array(
+      '#type' => 'select',
+      '#title' => $this->t('Select the feed that should be displayed'),
+      '#default_value' => $this->configuration['feed'],
+      '#options' => $options,
+    );
+    $range = range(2, 20);
+    $form['block_count'] = array(
+      '#type' => 'select',
+      '#title' => $this->t('Number of news items in block'),
+      '#default_value' => $this->configuration['block_count'],
+      '#options' => array_combine($range, $range),
+    );
+    return $form;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function blockSubmit($form, FormStateInterface $form_state) {
+    $this->configuration['block_count'] = $form_state->getValue('block_count');
+    $this->configuration['feed'] = $form_state->getValue('feed');
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function build() {
+    // Load the selected feed.
+    if ($feed = $this->feedStorage->load($this->configuration['feed'])) {
+      $result = $this->itemQuery
+        ->condition('fid', $feed->id())
+        ->range(0, $this->configuration['block_count'])
+        ->sort('timestamp', 'DESC')
+        ->sort('iid', 'DESC')
+        ->execute();
+
+      $items = $this->itemStorage->loadMultiple($result);
+
+      $more_link = array(
+        '#type' => 'more_link',
+        '#url' => $feed->urlInfo(),
+        '#attributes' => array('title' => $this->t("View this feed's recent news.")),
+      );
+      $read_more = drupal_render($more_link);
+      $rendered_items = array();
+      foreach ($items as $item) {
+        $aggregator_block_item = array(
+          '#type' => 'link',
+          '#url' => $item->urlInfo(),
+          '#title' => $item->label(),
+        );
+        $rendered_items[] = drupal_render($aggregator_block_item);
+      }
+      // Only display the block if there are items to show.
+      if (count($rendered_items) > 0) {
+        $item_list = array(
+          '#theme' => 'item_list',
+          '#items' => $rendered_items,
+        );
+        return array(
+          '#children' => drupal_render($item_list) . $read_more,
+        );
+      }
+    }
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function getCacheTags() {
+    $cache_tags = parent::getCacheTags();
+    $feed = $this->feedStorage->load($this->configuration['feed']);
+    return Cache::mergeTags($cache_tags, $feed->getCacheTags());
+  }
+
+}

core/modules/aggregator/src/Plugin/FetcherInterface.php

@@ -0,0 +1,42 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\aggregator\Plugin\FetcherInterface.
+ */
+
+namespace Drupal\aggregator\Plugin;
+
+use Drupal\aggregator\FeedInterface;
+
+/**
+ * Defines an interface for aggregator fetcher implementations.
+ *
+ * A fetcher downloads feed data to a Drupal site. The fetcher is called at the
+ * first of the three aggregation stages: first, data is downloaded by the
+ * active fetcher; second, it is converted to a common format by the active
+ * parser; and finally, it is passed to all active processors, which manipulate
+ * or store the data.
+ *
+ * @see \Drupal\aggregator\Annotation\AggregatorFetcher
+ * @see \Drupal\aggregator\Plugin\AggregatorPluginSettingsBase
+ * @see \Drupal\aggregator\Plugin\AggregatorPluginManager
+ * @see plugin_api
+ */
+interface FetcherInterface {
+
+  /**
+   * Downloads feed data.
+   *
+   * @param \Drupal\aggregator\FeedInterface $feed
+   *   A feed object representing the resource to be downloaded.
+   *   $feed->getUrl() contains the link to the feed.
+   *   Download the data at the URL and expose it
+   *   to other modules by attaching it to $feed->source_string.
+   *
+   * @return bool
+   *   TRUE if fetching was successful, FALSE otherwise.
+   */
+  public function fetch(FeedInterface $feed);
+
+}

core/modules/aggregator/src/Plugin/Field/FieldFormatter/AggregatorTitleFormatter.php

@@ -0,0 +1,90 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\aggregator\Plugin\Field\FieldFormatter\AggregatorTitleFormatter.
+ */
+
+namespace Drupal\aggregator\Plugin\Field\FieldFormatter;
+
+use Drupal\Core\Field\FieldDefinitionInterface;
+use Drupal\Core\Field\FieldItemListInterface;
+use Drupal\Core\Field\FormatterBase;
+use Drupal\Core\Form\FormStateInterface;
+use Drupal\Core\Url;
+
+/**
+ * Plugin implementation of the 'aggregator_title' formatter.
+ *
+ * @FieldFormatter(
+ *   id = "aggregator_title",
+ *   label = @Translation("Aggregator title"),
+ *   description = @Translation("Formats an aggregator item or feed title with an optional link."),
+ *   field_types = {
+ *     "string"
+ *   }
+ * )
+ */
+class AggregatorTitleFormatter extends FormatterBase {
+  /**
+   * {@inheritdoc}
+   */
+  public static function defaultSettings() {
+    $options = parent::defaultSettings();
+
+    $options['display_as_link'] = TRUE;
+    return $options;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function settingsForm(array $form, FormStateInterface $form_state) {
+    $form = parent::settingsForm($form, $form_state);
+
+    $form['display_as_link'] = [
+      '#type' => 'checkbox',
+      '#title' => $this->t('Link to URL'),
+      '#default_value' => $this->getSetting('display_as_link'),
+    ];
+
+    return $form;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function viewElements(FieldItemListInterface $items) {
+    $elements = [];
+
+    if ($items->getEntity()->getEntityTypeId() == 'aggregator_feed') {
+      $url_string = $items->getEntity()->getUrl();
+    }
+    else {
+      $url_string = $items->getEntity()->getLink();
+    }
+
+    foreach ($items as $delta => $item) {
+        if ($this->getSetting('display_as_link') && $url_string) {
+          $elements[$delta] = [
+            '#type' => 'link',
+            '#title' => $item->value,
+            '#url' => Url::fromUri($url_string),
+          ];
+        }
+        else {
+          $elements[$delta] = ['#markup' => $item->value];
+        }
+      }
+
+    return $elements;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public static function isApplicable(FieldDefinitionInterface $field_definition) {
+    return (($field_definition->getTargetEntityTypeId() === 'aggregator_item' || $field_definition->getTargetEntityTypeId() === 'aggregator_feed') && $field_definition->getName() === 'title');
+  }
+
+}

core/modules/aggregator/src/Plugin/Field/FieldFormatter/AggregatorXSSFormatter.php

@@ -0,0 +1,44 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\aggregator\Plugin\Field\FieldFormatter\AggregatorXSSFormatter.
+ */
+
+namespace Drupal\aggregator\Plugin\Field\FieldFormatter;
+
+use Drupal\Core\Field\FieldDefinitionInterface;
+use Drupal\Core\Field\FieldItemListInterface;
+use Drupal\Core\Field\FormatterBase;
+use Drupal\Core\Form\FormStateInterface;
+
+/**
+ * Plugin implementation of the 'aggregator_xss' formatter.
+ *
+ * @FieldFormatter(
+ *   id = "aggregator_xss",
+ *   label = @Translation("Aggregator XSS"),
+ *   description = @Translation("Filter output for aggregator items"),
+ *   field_types = {
+ *     "string",
+ *     "string_long",
+ *   }
+ * )
+ */
+class AggregatorXSSFormatter extends FormatterBase {
+
+  /**
+   * {@inheritdoc}
+   */
+  public function viewElements(FieldItemListInterface $items) {
+    $elements = [];
+
+    foreach ($items as $delta => $item) {
+      $elements[$delta] = [
+        '#type' => 'markup',
+        '#markup' => aggregator_filter_xss($item->value),
+      ];
+    }
+    return $elements;
+  }
+}

core/modules/aggregator/src/Plugin/ParserInterface.php

@@ -0,0 +1,57 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\aggregator\Plugin\ParserInterface.
+ */
+
+namespace Drupal\aggregator\Plugin;
+
+use Drupal\aggregator\FeedInterface;
+
+/**
+ * Defines an interface for aggregator parser implementations.
+ *
+ * A parser converts feed item data to a common format. The parser is called
+ * at the second of the three aggregation stages: first, data is downloaded
+ * by the active fetcher; second, it is converted to a common format by the
+ * active parser; and finally, it is passed to all active processors which
+ * manipulate or store the data.
+ *
+ * @see \Drupal\aggregator\Annotation\AggregatorParser
+ * @see \Drupal\aggregator\Plugin\AggregatorPluginSettingsBase
+ * @see \Drupal\aggregator\Plugin\AggregatorPluginManager
+ * @see plugin_api
+ */
+interface ParserInterface {
+
+  /**
+   * Parses feed data.
+   *
+   * @param \Drupal\aggregator\FeedInterface $feed
+   *   An object describing the resource to be parsed.
+   *   $feed->source_string->value contains the raw feed data. Parse the data
+   *   and add the following properties to the $feed object:
+   *   - description: The human-readable description of the feed.
+   *   - link: A full URL that directly relates to the feed.
+   *   - image: An image URL used to display an image of the feed.
+   *   - etag: An entity tag from the HTTP header used for cache validation to
+   *     determine if the content has been changed.
+   *   - modified: The UNIX timestamp when the feed was last modified.
+   *   - items: An array of feed items. The common format for a single feed item
+   *     is an associative array containing:
+   *     - title: The human-readable title of the feed item.
+   *     - description: The full body text of the item or a summary.
+   *     - timestamp: The UNIX timestamp when the feed item was last published.
+   *     - author: The author of the feed item.
+   *     - guid: The global unique identifier (GUID) string that uniquely
+   *       identifies the item. If not available, the link is used to identify
+   *       the item.
+   *     - link: A full URL to the individual feed item.
+   *
+   * @return bool
+   *   TRUE if parsing was successful, FALSE otherwise.
+   */
+  public function parse(FeedInterface $feed);
+
+}

core/modules/aggregator/src/Plugin/ProcessorInterface.php

@@ -0,0 +1,64 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\aggregator\Plugin\ProcessorInterface.
+ */
+
+namespace Drupal\aggregator\Plugin;
+
+use Drupal\aggregator\FeedInterface;
+
+/**
+ * Defines an interface for aggregator processor implementations.
+ *
+ * A processor acts on parsed feed data. Active processors are called at the
+ * third and last of the aggregation stages: first, data is downloaded by the
+ * active fetcher; second, it is converted to a common format by the active
+ * parser; and finally, it is passed to all active processors that manipulate or
+ * store the data.
+ *
+ * @see \Drupal\aggregator\Annotation\AggregatorProcessor
+ * @see \Drupal\aggregator\Plugin\AggregatorPluginSettingsBase
+ * @see \Drupal\aggregator\Plugin\AggregatorPluginManager
+ * @see plugin_api
+ */
+interface ProcessorInterface {
+
+  /**
+   * Processes feed data.
+   *
+   * @param \Drupal\aggregator\FeedInterface $feed
+   *   A feed object representing the resource to be processed.
+   *   $feed->items contains an array of feed items downloaded and parsed at the
+   *   parsing stage. See \Drupal\aggregator\Plugin\FetcherInterface::parse()
+   *   for the basic format of a single item in the $feed->items array.
+   *   For the exact format refer to the particular parser in use.
+   */
+  public function process(FeedInterface $feed);
+
+  /**
+   * Refreshes feed information.
+   *
+   * Called after the processing of the feed is completed by all selected
+   * processors.
+   *
+   * @param \Drupal\aggregator\FeedInterface $feed
+   *   Object describing feed.
+   *
+   * @see aggregator_refresh()
+   */
+  public function postProcess(FeedInterface $feed);
+
+  /**
+   * Deletes stored feed data.
+   *
+   * Called by aggregator if either a feed is deleted or a user clicks on
+   * "delete items".
+   *
+   * @param \Drupal\aggregator\FeedInterface $feed
+   *   The $feed object whose items are being deleted.
+   */
+  public function delete(FeedInterface $feed);
+
+}

core/modules/aggregator/src/Plugin/QueueWorker/AggregatorRefresh.php

@@ -0,0 +1,33 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\aggregator\Plugin\QueueWorker\AggregatorRefresh.
+ */
+
+namespace Drupal\aggregator\Plugin\QueueWorker;
+
+use Drupal\aggregator\FeedInterface;
+use Drupal\Core\Queue\QueueWorkerBase;
+
+/**
+ * Updates a feed's items.
+ *
+ * @QueueWorker(
+ *   id = "aggregator_feeds",
+ *   title = @Translation("Aggregator refresh"),
+ *   cron = {"time" = 60}
+ * )
+ */
+class AggregatorRefresh extends QueueWorkerBase {
+
+  /**
+   * {@inheritdoc}
+   */
+  public function processItem($data) {
+    if ($data instanceof FeedInterface) {
+      $data->refreshItems();
+    }
+  }
+
+}

core/modules/aggregator/src/Plugin/Validation/Constraint/FeedTitleConstraint.php

@@ -0,0 +1,31 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\aggregator\Plugin\Validation\Constraint\FeedTitleConstraint.
+ */
+
+namespace Drupal\aggregator\Plugin\Validation\Constraint;
+
+use Symfony\Component\Validator\Constraint;
+
+/**
+ * Supports validating feed titles.
+ *
+ * @Constraint(
+ *   id = "FeedTitle",
+ *   label = @Translation("Feed title", context = "Validation")
+ * )
+ */
+class FeedTitleConstraint extends Constraint {
+
+  public $message = 'A feed named %value already exists. Enter a unique title.';
+
+  /**
+   * {@inheritdoc}
+   */
+  public function validatedBy() {
+    return '\Drupal\Core\Validation\Plugin\Validation\Constraint\UniqueFieldValueValidator';
+  }
+
+}

core/modules/aggregator/src/Plugin/Validation/Constraint/FeedUrlConstraint.php

@@ -0,0 +1,31 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\aggregator\Plugin\Validation\Constraint\FeedUrlConstraint.
+ */
+
+namespace Drupal\aggregator\Plugin\Validation\Constraint;
+
+use Symfony\Component\Validator\Constraint;
+
+/**
+ * Supports validating feed URLs.
+ *
+ * @Constraint(
+ *   id = "FeedUrl",
+ *   label = @Translation("Feed URL", context = "Validation")
+ * )
+ */
+class FeedUrlConstraint extends Constraint {
+
+  public $message = 'A feed with this URL %value already exists. Enter a unique URL.';
+
+  /**
+   * {@inheritdoc}
+   */
+  public function validatedBy() {
+    return '\Drupal\Core\Validation\Plugin\Validation\Constraint\UniqueFieldValueValidator';
+  }
+
+}

core/modules/aggregator/src/Plugin/aggregator/fetcher/DefaultFetcher.php

@@ -0,0 +1,110 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\aggregator\Plugin\aggregator\fetcher\DefaultFetcher.
+ */
+
+namespace Drupal\aggregator\Plugin\aggregator\fetcher;
+
+use Drupal\aggregator\Plugin\FetcherInterface;
+use Drupal\aggregator\FeedInterface;
+use Drupal\Component\Datetime\DateTimePlus;
+use Drupal\Core\Plugin\ContainerFactoryPluginInterface;
+use GuzzleHttp\ClientInterface;
+use GuzzleHttp\Exception\RequestException;
+use Psr\Log\LoggerInterface;
+use Symfony\Component\DependencyInjection\ContainerInterface;
+
+/**
+ * Defines a default fetcher implementation.
+ *
+ * Uses the http_client service to download the feed.
+ *
+ * @AggregatorFetcher(
+ *   id = "aggregator",
+ *   title = @Translation("Default fetcher"),
+ *   description = @Translation("Downloads data from a URL using Drupal's HTTP request handler.")
+ * )
+ */
+class DefaultFetcher implements FetcherInterface, ContainerFactoryPluginInterface {
+
+  /**
+   * The HTTP client to fetch the feed data with.
+   *
+   * @var \GuzzleHttp\ClientInterface
+   */
+  protected $httpClient;
+
+  /**
+   * A logger instance.
+   *
+   * @var \Psr\Log\LoggerInterface
+   */
+  protected $logger;
+
+  /**
+   * Constructs a DefaultFetcher object.
+   *
+   * @param \GuzzleHttp\ClientInterface $http_client
+   *   A Guzzle client object.
+   * @param \Psr\Log\LoggerInterface $logger
+   *   A logger instance.
+   */
+  public function __construct(ClientInterface $http_client, LoggerInterface $logger) {
+    $this->httpClient = $http_client;
+    $this->logger = $logger;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public static function create(ContainerInterface $container, array $configuration, $plugin_id, $plugin_definition) {
+    return new static(
+      $container->get('http_client'),
+      $container->get('logger.factory')->get('aggregator')
+    );
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function fetch(FeedInterface $feed) {
+    $request = $this->httpClient->createRequest('GET', $feed->getUrl());
+    $feed->source_string = FALSE;
+
+    // Generate conditional GET headers.
+    if ($feed->getEtag()) {
+      $request->addHeader('If-None-Match', $feed->getEtag());
+    }
+    if ($feed->getLastModified()) {
+      $request->addHeader('If-Modified-Since', gmdate(DateTimePlus::RFC7231, $feed->getLastModified()));
+    }
+
+    try {
+      $response = $this->httpClient->send($request);
+
+      // In case of a 304 Not Modified, there is no new content, so return
+      // FALSE.
+      if ($response->getStatusCode() == 304) {
+        return FALSE;
+      }
+
+      $feed->source_string = (string) $response->getBody();
+      $feed->setEtag($response->getHeader('ETag'));
+      $feed->setLastModified(strtotime($response->getHeader('Last-Modified')));
+      $feed->http_headers = $response->getHeaders();
+
+      // Update the feed URL in case of a 301 redirect.
+      if ($response->getEffectiveUrl() != $feed->getUrl()) {
+        $feed->setUrl($response->getEffectiveUrl());
+      }
+      return TRUE;
+    }
+    catch (RequestException $e) {
+      $this->logger->warning('The feed from %site seems to be broken because of error "%error".', array('%site' => $feed->label(), '%error' => $e->getMessage()));
+      drupal_set_message(t('The feed from %site seems to be broken because of error "%error".', array('%site' => $feed->label(), '%error' => $e->getMessage())), 'warning');
+      return FALSE;
+    }
+  }
+}

core/modules/aggregator/src/Plugin/aggregator/parser/DefaultParser.php

@@ -0,0 +1,74 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\aggregator\Plugin\aggregator\parser\DefaultParser.
+ */
+
+namespace Drupal\aggregator\Plugin\aggregator\parser;
+
+use Drupal\aggregator\Plugin\ParserInterface;
+use Drupal\aggregator\FeedInterface;
+use Zend\Feed\Reader\Reader;
+use Zend\Feed\Reader\Exception\ExceptionInterface;
+
+/**
+ * Defines a default parser implementation.
+ *
+ * Parses RSS, Atom and RDF feeds.
+ *
+ * @AggregatorParser(
+ *   id = "aggregator",
+ *   title = @Translation("Default parser"),
+ *   description = @Translation("Default parser for RSS, Atom and RDF feeds.")
+ * )
+ */
+class DefaultParser implements ParserInterface {
+
+  /**
+   * {@inheritdoc}
+   */
+  public function parse(FeedInterface $feed) {
+    // Set our bridge extension manager to Zend Feed.
+    Reader::setExtensionManager(\Drupal::service('feed.bridge.reader'));
+    try {
+      $channel = Reader::importString($feed->source_string);
+    }
+    catch (ExceptionInterface $e) {
+      watchdog_exception('aggregator', $e);
+      drupal_set_message(t('The feed from %site seems to be broken because of error "%error".', array('%site' => $feed->label(), '%error' => $e->getMessage())), 'error');
+
+      return FALSE;
+    }
+
+    $feed->setWebsiteUrl($channel->getLink());
+    $feed->setDescription($channel->getDescription());
+    if ($image = $channel->getImage()) {
+      $feed->setImage($image['uri']);
+    }
+    // Initialize items array.
+    $feed->items = array();
+    foreach ($channel as $item) {
+      // Reset the parsed item.
+      $parsed_item = array();
+      // Move the values to an array as expected by processors.
+      $parsed_item['title'] = $item->getTitle();
+      $parsed_item['guid'] = $item->getId();
+      $parsed_item['link'] = $item->getLink();
+      $parsed_item['description'] = $item->getDescription();
+      $parsed_item['author'] = '';
+      if ($author = $item->getAuthor()) {
+        $parsed_item['author'] = $author['name'];
+      }
+      $parsed_item['timestamp'] = '';
+      if ($date = $item->getDateModified()) {
+        $parsed_item['timestamp'] = $date->getTimestamp();
+      }
+      // Store on $feed object. This is where processors will look for parsed items.
+      $feed->items[] = $parsed_item;
+    }
+
+    return TRUE;
+  }
+
+}

core/modules/aggregator/src/Plugin/aggregator/processor/DefaultProcessor.php

@@ -0,0 +1,294 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\aggregator\Plugin\aggregator\processor\DefaultProcessor.
+ */
+
+namespace Drupal\aggregator\Plugin\aggregator\processor;
+
+use Drupal\aggregator\ItemStorageInterface;
+use Drupal\aggregator\Plugin\AggregatorPluginSettingsBase;
+use Drupal\aggregator\Plugin\ProcessorInterface;
+use Drupal\aggregator\FeedInterface;
+use Drupal\Component\Utility\Unicode;
+use Drupal\Core\Database\Database;
+use Drupal\Core\Config\ConfigFactoryInterface;
+use Drupal\Core\Datetime\DateFormatter;
+use Drupal\Core\Entity\Query\QueryInterface;
+use Drupal\Core\Form\ConfigFormBaseTrait;
+use Drupal\Core\Form\FormStateInterface;
+use Drupal\Core\Plugin\ContainerFactoryPluginInterface;
+use Drupal\Core\Routing\UrlGeneratorTrait;
+use Symfony\Component\DependencyInjection\ContainerInterface;
+
+/**
+ * Defines a default processor implementation.
+ *
+ * Creates lightweight records from feed items.
+ *
+ * @AggregatorProcessor(
+ *   id = "aggregator",
+ *   title = @Translation("Default processor"),
+ *   description = @Translation("Creates lightweight records from feed items.")
+ * )
+ */
+class DefaultProcessor extends AggregatorPluginSettingsBase implements ProcessorInterface, ContainerFactoryPluginInterface {
+  use ConfigFormBaseTrait;
+  use UrlGeneratorTrait;
+
+  /**
+   * Contains the configuration object factory.
+   *
+   * @var \Drupal\Core\Config\ConfigFactoryInterface
+   */
+  protected $configFactory;
+
+  /**
+   * The entity query object for feed items.
+   *
+   * @var \Drupal\Core\Entity\Query\QueryInterface
+   */
+  protected $itemQuery;
+
+  /**
+   * The entity storage for items.
+   *
+   * @var \Drupal\aggregator\ItemStorageInterface
+   */
+  protected $itemStorage;
+
+  /**
+   * The date formatter service.
+   *
+   * @var \Drupal\Core\Datetime\DateFormatter
+   */
+  protected $dateFormatter;
+
+  /**
+   * Constructs a DefaultProcessor object.
+   *
+   * @param array $configuration
+   *   A configuration array containing information about the plugin instance.
+   * @param string $plugin_id
+   *   The plugin_id for the plugin instance.
+   * @param mixed $plugin_definition
+   *   The plugin implementation definition.
+   * @param \Drupal\Core\Config\ConfigFactoryInterface $config
+   *   The configuration factory object.
+   * @param \Drupal\Core\Entity\Query\QueryInterface $item_query
+   *   The entity query object for feed items.
+   * @param \Drupal\aggregator\ItemStorageInterface $item_storage
+   *   The entity storage for feed items.
+   * @param \Drupal\Core\Datetime\DateFormatter $date_formatter
+   *   The date formatter service.
+   */
+  public function __construct(array $configuration, $plugin_id, $plugin_definition, ConfigFactoryInterface $config, QueryInterface $item_query, ItemStorageInterface $item_storage, DateFormatter $date_formatter) {
+    $this->configFactory = $config;
+    $this->itemStorage = $item_storage;
+    $this->itemQuery = $item_query;
+    $this->dateFormatter = $date_formatter;
+    // @todo Refactor aggregator plugins to ConfigEntity so merging
+    //   the configuration here is not needed.
+    parent::__construct($configuration + $this->getConfiguration(), $plugin_id, $plugin_definition);
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public static function create(ContainerInterface $container, array $configuration, $plugin_id, $plugin_definition) {
+    return new static(
+      $configuration,
+      $plugin_id,
+      $plugin_definition,
+      $container->get('config.factory'),
+      $container->get('entity.query')->get('aggregator_item'),
+      $container->get('entity.manager')->getStorage('aggregator_item'),
+      $container->get('date.formatter')
+    );
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  protected function getEditableConfigNames() {
+    return ['aggregator.settings'];
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function buildConfigurationForm(array $form, FormStateInterface $form_state) {
+    $config = $this->config('aggregator.settings');
+    $processors = $config->get('processors');
+    $info = $this->getPluginDefinition();
+    $counts = array(3, 5, 10, 15, 20, 25);
+    $items = array_map(function ($count) {
+      return $this->formatPlural($count, '1 item', '@count items');
+    }, array_combine($counts, $counts));
+    $intervals = array(3600, 10800, 21600, 32400, 43200, 86400, 172800, 259200, 604800, 1209600, 2419200, 4838400, 9676800);
+    $period = array_map(array($this->dateFormatter, 'formatInterval'), array_combine($intervals, $intervals));
+    $period[AGGREGATOR_CLEAR_NEVER] = t('Never');
+
+    $form['processors'][$info['id']] = array();
+    // Only wrap into details if there is a basic configuration.
+    if (isset($form['basic_conf'])) {
+      $form['processors'][$info['id']] = array(
+        '#type' => 'details',
+        '#title' => t('Default processor settings'),
+        '#description' => $info['description'],
+        '#open' => in_array($info['id'], $processors),
+      );
+    }
+
+    $form['processors'][$info['id']]['aggregator_summary_items'] = array(
+      '#type' => 'select',
+      '#title' => t('Number of items shown in listing pages'),
+      '#default_value' => $config->get('source.list_max'),
+      '#empty_value' => 0,
+      '#options' => $items,
+    );
+
+    $form['processors'][$info['id']]['aggregator_clear'] = array(
+      '#type' => 'select',
+      '#title' => t('Discard items older than'),
+      '#default_value' => $config->get('items.expire'),
+      '#options' => $period,
+      '#description' => t('Requires a correctly configured <a href="@cron">cron maintenance task</a>.', array('@cron' => $this->url('system.status'))),
+    );
+
+    $lengths = array(0, 200, 400, 600, 800, 1000, 1200, 1400, 1600, 1800, 2000);
+    $options = array_map(function($length) {
+      return ($length == 0) ? t('Unlimited') : $this->formatPlural($length, '1 character', '@count characters');
+    }, array_combine($lengths, $lengths));
+
+    $form['processors'][$info['id']]['aggregator_teaser_length'] = array(
+      '#type' => 'select',
+      '#title' => t('Length of trimmed description'),
+      '#default_value' => $config->get('items.teaser_length'),
+      '#options' => $options,
+      '#description' => t('The maximum number of characters used in the trimmed version of content.'),
+    );
+    return $form;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function submitConfigurationForm(array &$form, FormStateInterface $form_state) {
+    $this->configuration['items']['expire'] = $form_state->getValue('aggregator_clear');
+    $this->configuration['items']['teaser_length'] = $form_state->getValue('aggregator_teaser_length');
+    $this->configuration['source']['list_max'] = $form_state->getValue('aggregator_summary_items');
+    // @todo Refactor aggregator plugins to ConfigEntity so this is not needed.
+    $this->setConfiguration($this->configuration);
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function process(FeedInterface $feed) {
+    if (!is_array($feed->items)) {
+      return;
+    }
+    foreach ($feed->items as $item) {
+      // @todo: The default entity view builder always returns an empty
+      //   array, which is ignored in aggregator_save_item() currently. Should
+      //   probably be fixed.
+      if (empty($item['title'])) {
+        continue;
+      }
+
+      // Save this item. Try to avoid duplicate entries as much as possible. If
+      // we find a duplicate entry, we resolve it and pass along its ID is such
+      // that we can update it if needed.
+      if (!empty($item['guid'])) {
+        $values = array('fid' => $feed->id(), 'guid' => $item['guid']);
+      }
+      elseif ($item['link'] && $item['link'] != $feed->link && $item['link'] != $feed->url) {
+        $values = array('fid' => $feed->id(), 'link' => $item['link']);
+      }
+      else {
+        $values = array('fid' => $feed->id(), 'title' => $item['title']);
+      }
+
+      // Try to load an existing entry.
+      if ($entry = entity_load_multiple_by_properties('aggregator_item', $values)) {
+        $entry = reset($entry);
+      }
+      else {
+        $entry = entity_create('aggregator_item', array('langcode' => $feed->language()->getId()));
+      }
+      if ($item['timestamp']) {
+        $entry->setPostedTime($item['timestamp']);
+      }
+
+      // Make sure the item title and author fit in the 255 varchar column.
+      $entry->setTitle(Unicode::truncate($item['title'], 255, TRUE, TRUE));
+      $entry->setAuthor(Unicode::truncate($item['author'], 255, TRUE, TRUE));
+
+      $entry->setFeedId($feed->id());
+      $entry->setLink($item['link']);
+      $entry->setGuid($item['guid']);
+
+      $description = '';
+      if (!empty($item['description'])) {
+        $description = $item['description'];
+      }
+      $entry->setDescription($description);
+
+      $entry->save();
+    }
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function delete(FeedInterface $feed) {
+    if ($items = $this->itemStorage->loadByFeed($feed->id())) {
+      $this->itemStorage->delete($items);
+    }
+    // @todo This should be moved out to caller with a different message maybe.
+    drupal_set_message(t('The news items from %site have been deleted.', array('%site' => $feed->label())));
+  }
+
+  /**
+   * Implements \Drupal\aggregator\Plugin\ProcessorInterface::postProcess().
+   *
+   * Expires items from a feed depending on expiration settings.
+   */
+  public function postProcess(FeedInterface $feed) {
+    $aggregator_clear = $this->configuration['items']['expire'];
+
+    if ($aggregator_clear != AGGREGATOR_CLEAR_NEVER) {
+      // Delete all items that are older than flush item timer.
+      $age = REQUEST_TIME - $aggregator_clear;
+      $result = $this->itemQuery
+        ->condition('fid', $feed->id())
+        ->condition('timestamp', $age, '<')
+        ->execute();
+      if ($result) {
+        $entities = $this->itemStorage->loadMultiple($result);
+        $this->itemStorage->delete($entities);
+      }
+    }
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function getConfiguration() {
+    return $this->configFactory->get('aggregator.settings')->get();
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function setConfiguration(array $configuration) {
+    $config = $this->config('aggregator.settings');
+    foreach ($configuration as $key => $value) {
+      $config->set($key, $value);
+    }
+    $config->save();
+  }
+
+}

core/modules/aggregator/src/Plugin/views/argument/Fid.php

@@ -0,0 +1,68 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\aggregator\Plugin\views\argument\Fid.
+ */
+
+namespace Drupal\aggregator\Plugin\views\argument;
+
+use Drupal\Core\Entity\EntityManagerInterface;
+use Drupal\views\Plugin\views\argument\NumericArgument;
+use Drupal\Component\Utility\SafeMarkup;
+use Symfony\Component\DependencyInjection\ContainerInterface;
+
+/**
+ * Argument handler to accept an aggregator feed id.
+ *
+ * @ingroup views_argument_handlers
+ *
+ * @ViewsArgument("aggregator_fid")
+ */
+class Fid extends NumericArgument {
+
+  /**
+   * The entity manager service.
+   *
+   * @var \Drupal\Core\Entity\EntityManagerInterface
+   */
+  protected $entityManager;
+
+  /**
+   * Constructs a Drupal\Component\Plugin\PluginBase object.
+   *
+   * @param array $configuration
+   *   A configuration array containing information about the plugin instance.
+   * @param string $plugin_id
+   *   The plugin_id for the plugin instance.
+   * @param mixed $plugin_definition
+   *   The plugin implementation definition.
+   * @param \Drupal\Core\Entity\EntityManagerInterface $entity_manager
+   *   The entity manager.
+   */
+  public function __construct(array $configuration, $plugin_id, $plugin_definition, EntityManagerInterface $entity_manager) {
+    parent::__construct($configuration, $plugin_id, $plugin_definition);
+    $this->entityManager = $entity_manager;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public static function create(ContainerInterface $container, array $configuration, $plugin_id, $plugin_definition) {
+    return new static($configuration, $plugin_id, $plugin_definition, $container->get('entity.manager'));
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function titleQuery() {
+    $titles = array();
+
+    $feeds = $this->entityManager->getStorage('aggregator_feed')->loadMultiple($this->value);
+    foreach ($feeds as $feed) {
+      $titles[] = SafeMarkup::checkPlain($feed->label());
+    }
+    return $titles;
+  }
+
+}

core/modules/aggregator/src/Plugin/views/argument/Iid.php

@@ -0,0 +1,68 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\aggregator\Plugin\views\argument\Iid.
+ */
+
+namespace Drupal\aggregator\Plugin\views\argument;
+
+use Drupal\Core\Entity\EntityManagerInterface;
+use Drupal\views\Plugin\views\argument\NumericArgument;
+use Drupal\Component\Utility\SafeMarkup;
+use Symfony\Component\DependencyInjection\ContainerInterface;
+
+/**
+ * Argument handler to accept an aggregator item id.
+ *
+ * @ingroup views_argument_handlers
+ *
+ * @ViewsArgument("aggregator_iid")
+ */
+class Iid extends NumericArgument {
+
+  /**
+   * The entity manager service.
+   *
+   * @var \Drupal\Core\Entity\EntityManagerInterface
+   */
+  protected $entityManager;
+
+  /**
+   * Constructs a Drupal\Component\Plugin\PluginBase object.
+   *
+   * @param array $configuration
+   *   A configuration array containing information about the plugin instance.
+   * @param string $plugin_id
+   *   The plugin_id for the plugin instance.
+   * @param mixed $plugin_definition
+   *   The plugin implementation definition.
+   * @param \Drupal\Core\Entity\EntityManagerInterface $entity_manager
+   *   The entity manager.
+   */
+  public function __construct(array $configuration, $plugin_id, $plugin_definition, EntityManagerInterface $entity_manager) {
+    parent::__construct($configuration, $plugin_id, $plugin_definition);
+    $this->entityManager = $entity_manager;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public static function create(ContainerInterface $container, array $configuration, $plugin_id, $plugin_definition) {
+    return new static($configuration, $plugin_id, $plugin_definition, $container->get('entity.manager'));
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function titleQuery() {
+    $titles = array();
+
+    $items = $this->entityManager->getStorage('aggregator_item')->loadMultiple($this->value);
+    foreach ($items as $feed) {
+      $titles[] = SafeMarkup::checkPlain($feed->label());
+    }
+    return $titles;
+  }
+
+}

core/modules/aggregator/src/Plugin/views/row/Rss.php

@@ -0,0 +1,85 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\aggregator\Plugin\views\row\Rss.
+ */
+
+namespace Drupal\aggregator\Plugin\views\row;
+
+use Drupal\views\Plugin\views\row\RssPluginBase;
+
+/**
+ * Defines a row plugin which loads an aggregator item and renders as RSS.
+ *
+ * @ViewsRow(
+ *   id = "aggregator_rss",
+ *   theme = "views_view_row_rss",
+ *   title = @Translation("Aggregator item"),
+ *   help = @Translation("Display the aggregator item using the data from the original source."),
+ *   base = {"aggregator_item"},
+ *   display_types = {"feed"}
+ * )
+ */
+class Rss extends RssPluginBase {
+
+  /**
+   * The table the aggregator item is using for storage.
+   *
+   * @var string
+   */
+  public $base_table = 'aggregator_item';
+
+  /**
+   * The actual field which is used to identify a aggregator item.
+   *
+   * @var string
+   */
+  public $base_field = 'iid';
+
+  /**
+   * {@inheritdoc}
+   */
+  protected $entityTypeId = 'aggregator_item';
+
+  /**
+   * {@inheritdoc}
+   */
+  public function render($row) {
+    $entity = $row->_entity;
+
+    $item = new \stdClass();
+    foreach ($entity as $name => $field) {
+      // views_view_row_rss takes care about the escaping.
+      $item->{$name} = $field->value;
+    }
+
+    $item->elements = array(
+      array(
+        'key' => 'pubDate',
+        // views_view_row_rss takes care about the escaping.
+        'value' => gmdate('r', $entity->timestamp->value),
+      ),
+      array(
+        'key' => 'dc:creator',
+        // views_view_row_rss takes care about the escaping.
+        'value' => $entity->author->value,
+      ),
+      array(
+        'key' => 'guid',
+        // views_view_row_rss takes care about the escaping.
+        'value' => $entity->guid->value,
+        'attributes' => array('isPermaLink' => 'false'),
+      ),
+    );
+
+    $build = array(
+      '#theme' => $this->themeFunctions(),
+      '#view' => $this->view,
+      '#options' => $this->options,
+      '#row' => $item,
+    );
+    return $build;
+  }
+
+}

core/modules/aggregator/src/Tests/AddFeedTest.php

@@ -0,0 +1,75 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\aggregator\Tests\AddFeedTest.
+ */
+
+namespace Drupal\aggregator\Tests;
+
+/**
+ * Add feed test.
+ *
+ * @group aggregator
+ */
+class AddFeedTest extends AggregatorTestBase {
+  /**
+   * Creates and ensures that a feed is unique, checks source, and deletes feed.
+   */
+  public function testAddFeed() {
+    $feed = $this->createFeed();
+    $feed->refreshItems();
+
+    // Check feed data.
+    $this->assertUrl(\Drupal::url('aggregator.feed_add', [], ['absolute' => TRUE]), [], 'Directed to correct url.');
+    $this->assertTrue($this->uniqueFeed($feed->label(), $feed->getUrl()), 'The feed is unique.');
+
+    // Check feed source.
+    $this->drupalGet('aggregator/sources/' . $feed->id());
+    $this->assertResponse(200, 'Feed source exists.');
+    $this->assertText($feed->label(), 'Page title');
+    $this->assertRaw($feed->getWebsiteUrl());
+
+    // Try to add a duplicate.
+    $edit = [
+      'title[0][value]' => $feed->label(),
+      'url[0][value]' => $feed->getUrl(),
+      'refresh' => '900',
+    ];
+    $this->drupalPostForm('aggregator/sources/add', $edit, t('Save'));
+    $this->assertRaw(t('A feed named %feed already exists. Enter a unique title.', array('%feed' => $feed->label())));
+    $this->assertRaw(t('A feed with this URL %url already exists. Enter a unique URL.', array('%url' => $feed->getUrl())));
+
+    // Delete feed.
+    $this->deleteFeed($feed);
+  }
+
+  /**
+   * Tests feeds with very long URLs.
+   */
+  public function testAddLongFeed() {
+    // Create a feed with a URL of > 255 characters.
+    $long_url = "https://www.google.com/search?ix=heb&sourceid=chrome&ie=UTF-8&q=angie+byron#sclient=psy-ab&hl=en&safe=off&source=hp&q=angie+byron&pbx=1&oq=angie+byron&aq=f&aqi=&aql=&gs_sm=3&gs_upl=0l0l0l10534l0l0l0l0l0l0l0l0ll0l0&bav=on.2,or.r_gc.r_pw.r_cp.,cf.osb&fp=a70b6b1f0abe28d8&biw=1629&bih=889&ix=heb";
+    $feed = $this->createFeed($long_url);
+    $feed->refreshItems();
+
+    // Create a second feed of > 255 characters, where the only difference is
+    // after the 255th character.
+    $long_url_2 = "https://www.google.com/search?ix=heb&sourceid=chrome&ie=UTF-8&q=angie+byron#sclient=psy-ab&hl=en&safe=off&source=hp&q=angie+byron&pbx=1&oq=angie+byron&aq=f&aqi=&aql=&gs_sm=3&gs_upl=0l0l0l10534l0l0l0l0l0l0l0l0ll0l0&bav=on.2,or.r_gc.r_pw.r_cp.,cf.osb&fp=a70b6b1f0abe28d8&biw=1629&bih=889";
+    $feed_2 = $this->createFeed($long_url_2);
+    $feed->refreshItems();
+
+    // Check feed data.
+    $this->assertTrue($this->uniqueFeed($feed->label(), $feed->getUrl()), 'The first long URL feed is unique.');
+    $this->assertTrue($this->uniqueFeed($feed_2->label(), $feed_2->getUrl()), 'The second long URL feed is unique.');
+
+    // Check feed source.
+    $this->drupalGet('aggregator/sources/' . $feed->id());
+    $this->assertResponse(200, 'Long URL feed source exists.');
+    $this->assertText($feed->label(), 'Page title');
+
+    // Delete feeds.
+    $this->deleteFeed($feed);
+    $this->deleteFeed($feed_2);
+  }
+}

core/modules/aggregator/src/Tests/AggregatorAdminTest.php

@@ -0,0 +1,88 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\aggregator\Tests\AggregatorAdminTest.
+ */
+
+namespace Drupal\aggregator\Tests;
+
+/**
+ * Tests aggregator admin pages.
+ *
+ * @group aggregator
+ */
+class AggregatorAdminTest extends AggregatorTestBase {
+
+  /**
+   * Tests the settings form to ensure the correct default values are used.
+   */
+  public function testSettingsPage() {
+    $this->drupalGet('admin/config');
+    $this->clickLink('Feed aggregator');
+    $this->clickLink('Settings');
+    // Make sure that test plugins are present.
+    $this->assertText('Test fetcher');
+    $this->assertText('Test parser');
+    $this->assertText('Test processor');
+
+    // Set new values and enable test plugins.
+    $edit = array(
+      'aggregator_allowed_html_tags' => '<a>',
+      'aggregator_summary_items' => 10,
+      'aggregator_clear' => 3600,
+      'aggregator_teaser_length' => 200,
+      'aggregator_fetcher' => 'aggregator_test_fetcher',
+      'aggregator_parser' => 'aggregator_test_parser',
+      'aggregator_processors[aggregator_test_processor]' => 'aggregator_test_processor',
+    );
+    $this->drupalPostForm('admin/config/services/aggregator/settings', $edit, t('Save configuration'));
+    $this->assertText(t('The configuration options have been saved.'));
+
+    foreach ($edit as $name => $value) {
+      $this->assertFieldByName($name, $value, format_string('"@name" has correct default value.', array('@name' => $name)));
+    }
+
+    // Check for our test processor settings form.
+    $this->assertText(t('Dummy length setting'));
+    // Change its value to ensure that settingsSubmit is called.
+    $edit = array(
+      'dummy_length' => 100,
+    );
+    $this->drupalPostForm('admin/config/services/aggregator/settings', $edit, t('Save configuration'));
+    $this->assertText(t('The configuration options have been saved.'));
+    $this->assertFieldByName('dummy_length', 100, '"dummy_length" has correct default value.');
+
+    // Make sure settings form is still accessible even after uninstalling a module
+    // that provides the selected plugins.
+    $this->container->get('module_installer')->uninstall(array('aggregator_test'));
+    $this->resetAll();
+    $this->drupalGet('admin/config/services/aggregator/settings');
+    $this->assertResponse(200);
+  }
+
+  /**
+   * Tests the overview page.
+   */
+  function testOverviewPage() {
+    $feed = $this->createFeed($this->getRSS091Sample());
+    $this->drupalGet('admin/config/services/aggregator');
+
+    $result = $this->xpath('//table/tbody/tr');
+    // Check if the amount of feeds in the overview matches the amount created.
+    $this->assertEqual(1, count($result), 'Created feed is found in the overview');
+    // Check if the fields in the table match with what's expected.
+    $this->assertEqual($feed->label(), (string) $result[0]->td[0]->a);
+    $count = $this->container->get('entity.manager')->getStorage('aggregator_item')->getItemCount($feed);
+    $this->assertEqual(\Drupal::translation()->formatPlural($count, '1 item', '@count items'), (string) $result[0]->td[1]);
+
+    // Update the items of the first feed.
+    $feed->refreshItems();
+    $this->drupalGet('admin/config/services/aggregator');
+    $result = $this->xpath('//table/tbody/tr');
+    // Check if the fields in the table match with what's expected.
+    $this->assertEqual($feed->label(), (string) $result[0]->td[0]->a);
+    $count = $this->container->get('entity.manager')->getStorage('aggregator_item')->getItemCount($feed);
+    $this->assertEqual(\Drupal::translation()->formatPlural($count, '1 item', '@count items'), (string) $result[0]->td[1]);
+  }
+}

core/modules/aggregator/src/Tests/AggregatorCronTest.php

@@ -0,0 +1,49 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\aggregator\Tests\AggregatorCronTest.
+ */
+
+namespace Drupal\aggregator\Tests;
+
+/**
+ * Update feeds on cron.
+ *
+ * @group aggregator
+ */
+class AggregatorCronTest extends AggregatorTestBase {
+  /**
+   * Adds feeds and updates them via cron process.
+   */
+  public function testCron() {
+    // Create feed and test basic updating on cron.
+    $this->createSampleNodes();
+    $feed = $this->createFeed();
+    $this->cronRun();
+    $this->assertEqual(5, db_query('SELECT COUNT(*) FROM {aggregator_item} WHERE fid = :fid', array(':fid' => $feed->id()))->fetchField());
+    $this->deleteFeedItems($feed);
+    $this->assertEqual(0, db_query('SELECT COUNT(*) FROM {aggregator_item} WHERE fid = :fid', array(':fid' => $feed->id()))->fetchField());
+    $this->cronRun();
+    $this->assertEqual(5, db_query('SELECT COUNT(*) FROM {aggregator_item} WHERE fid = :fid', array(':fid' => $feed->id()))->fetchField());
+
+    // Test feed locking when queued for update.
+    $this->deleteFeedItems($feed);
+    db_update('aggregator_feed')
+      ->condition('fid', $feed->id())
+      ->fields(array(
+        'queued' => REQUEST_TIME,
+      ))
+      ->execute();
+    $this->cronRun();
+    $this->assertEqual(0, db_query('SELECT COUNT(*) FROM {aggregator_item} WHERE fid = :fid', array(':fid' => $feed->id()))->fetchField());
+    db_update('aggregator_feed')
+      ->condition('fid', $feed->id())
+      ->fields(array(
+        'queued' => 0,
+      ))
+      ->execute();
+    $this->cronRun();
+    $this->assertEqual(5, db_query('SELECT COUNT(*) FROM {aggregator_item} WHERE fid = :fid', array(':fid' => $feed->id()))->fetchField());
+  }
+}

core/modules/aggregator/src/Tests/AggregatorRenderingTest.php

@@ -0,0 +1,148 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\aggregator\Tests\AggregatorRenderingTest.
+ */
+
+namespace Drupal\aggregator\Tests;
+
+use Drupal\Component\Utility\SafeMarkup;
+
+/**
+ * Tests display of aggregator items on the page.
+ *
+ * @group aggregator
+ */
+class AggregatorRenderingTest extends AggregatorTestBase {
+
+  /**
+   * Modules to install.
+   *
+   * @var array
+   */
+  public static $modules = array('block', 'test_page_test');
+
+  /**
+   * Adds a feed block to the page and checks its links.
+   */
+  public function testBlockLinks() {
+    // Create feed.
+    $this->createSampleNodes();
+    $feed = $this->createFeed();
+    $this->updateFeedItems($feed, $this->getDefaultFeedItemCount());
+
+    // Need admin user to be able to access block admin.
+    $admin_user = $this->drupalCreateUser(array(
+      'administer blocks',
+      'access administration pages',
+      'administer news feeds',
+      'access news feeds',
+    ));
+    $this->drupalLogin($admin_user);
+
+    $block = $this->drupalPlaceBlock("aggregator_feed_block", array('label' => 'feed-' . $feed->label()));
+
+    // Configure the feed that should be displayed.
+    $block->getPlugin()->setConfigurationValue('feed', $feed->id());
+    $block->getPlugin()->setConfigurationValue('block_count', 2);
+    $block->save();
+
+    // Confirm that the block is now being displayed on pages.
+    $this->drupalGet('test-page');
+    $this->assertText($block->label(), 'Feed block is displayed on the page.');
+
+    // Confirm items appear as links.
+    $items = $this->container->get('entity.manager')->getStorage('aggregator_item')->loadByFeed($feed->id(), 1);
+    $links = $this->xpath('//a[@href = :href]', array(':href' => reset($items)->getLink()));
+    $this->assert(isset($links[0]), 'Item link found.');
+
+    // Find the expected read_more link.
+    $href = $feed->url();
+    $links = $this->xpath('//a[@href = :href]', array(':href' => $href));
+    $this->assert(isset($links[0]), format_string('Link to href %href found.', array('%href' => $href)));
+    $cache_tags_header = $this->drupalGetHeader('X-Drupal-Cache-Tags');
+    $cache_tags = explode(' ', $cache_tags_header);
+    $this->assertTrue(in_array('aggregator_feed:' . $feed->id(), $cache_tags));
+
+    // Visit that page.
+    $this->drupalGet($feed->urlInfo()->getInternalPath());
+    $correct_titles = $this->xpath('//h1[normalize-space(text())=:title]', array(':title' => $feed->label()));
+    $this->assertFalse(empty($correct_titles), 'Aggregator feed page is available and has the correct title.');
+    $cache_tags = explode(' ', $this->drupalGetHeader('X-Drupal-Cache-Tags'));
+    $this->assertTrue(in_array('aggregator_feed:' . $feed->id(), $cache_tags));
+    $this->assertTrue(in_array('aggregator_feed_view', $cache_tags));
+    $this->assertTrue(in_array('aggregator_item_view', $cache_tags));
+
+    // Set the number of news items to 0 to test that the block does not show
+    // up.
+    $block->getPlugin()->setConfigurationValue('block_count', 0);
+    $block->save();
+    // Check that the block is no longer displayed.
+    $this->drupalGet('test-page');
+    $this->assertNoText($block->label(), 'Feed block is not displayed on the page when number of items is set to 0.');
+  }
+
+  /**
+   * Creates a feed and checks that feed's page.
+   */
+  public function testFeedPage() {
+    // Increase the number of items published in the rss.xml feed so we have
+    // enough articles to test paging.
+    $view = entity_load('view', 'frontpage');
+    $display = &$view->getDisplay('feed_1');
+    $display['display_options']['pager']['options']['items_per_page'] = 30;
+    $view->save();
+
+    // Create a feed with 30 items.
+    $this->createSampleNodes(30);
+    $feed = $this->createFeed();
+    $this->updateFeedItems($feed, 30);
+
+    // Check for presence of an aggregator pager.
+    $this->drupalGet('aggregator');
+    $elements = $this->xpath("//ul[contains(@class, :class)]", array(':class' => 'pager__items'));
+    $this->assertTrue(!empty($elements), 'Individual source page contains a pager.');
+
+    // Check for sources page title.
+    $this->drupalGet('aggregator/sources');
+    $titles = $this->xpath('//h1[normalize-space(text())=:title]', array(':title' => 'Sources'));
+    $this->assertTrue(!empty($titles), 'Source page contains correct title.');
+
+    // Find the expected read_more link on the sources page.
+    $href = $feed->url();
+    $links = $this->xpath('//a[@href = :href]', array(':href' => $href));
+    $this->assertTrue(isset($links[0]), SafeMarkup::format('Link to href %href found.', array('%href' => $href)));
+    $cache_tags_header = $this->drupalGetHeader('X-Drupal-Cache-Tags');
+    $cache_tags = explode(' ', $cache_tags_header);
+    $this->assertTrue(in_array('aggregator_feed:' . $feed->id(), $cache_tags));
+
+    // Check the rss aggregator page as anonymous user.
+    $this->drupalLogout();
+    $this->drupalGet('aggregator/rss');
+    $this->assertResponse(403);
+
+    // Check the rss aggregator page as admin.
+    $this->drupalLogin($this->adminUser);
+    $this->drupalGet('aggregator/rss');
+    $this->assertResponse(200);
+    $this->assertEqual($this->drupalGetHeader('Content-type'), 'application/rss+xml; charset=utf-8');
+
+    // Check the opml aggregator page.
+    $this->drupalGet('aggregator/opml');
+    $outline = $this->xpath('//outline[1]');
+    $this->assertEqual($outline[0]['type'], 'rss', 'The correct type attribute is used for rss OPML.');
+    $this->assertEqual($outline[0]['text'], $feed->label(), 'The correct text attribute is used for rss OPML.');
+    $this->assertEqual($outline[0]['xmlurl'], $feed->getUrl(), 'The correct xmlUrl attribute is used for rss OPML.');
+
+    // Check for the presence of a pager.
+    $this->drupalGet('aggregator/sources/' . $feed->id());
+    $elements = $this->xpath("//ul[contains(@class, :class)]", array(':class' => 'pager__items'));
+    $this->assertTrue(!empty($elements), 'Individual source page contains a pager.');
+    $cache_tags = explode(' ', $this->drupalGetHeader('X-Drupal-Cache-Tags'));
+    $this->assertTrue(in_array('aggregator_feed:' . $feed->id(), $cache_tags));
+    $this->assertTrue(in_array('aggregator_feed_view', $cache_tags));
+    $this->assertTrue(in_array('aggregator_item_view', $cache_tags));
+  }
+
+}

core/modules/aggregator/src/Tests/AggregatorTestBase.php

@@ -0,0 +1,376 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\aggregator\Tests\AggregatorTestBase.
+ */
+
+namespace Drupal\aggregator\Tests;
+
+use Drupal\aggregator\Entity\Feed;
+use Drupal\simpletest\WebTestBase;
+use Drupal\aggregator\FeedInterface;
+
+/**
+ * Defines a base class for testing the Aggregator module.
+ */
+abstract class AggregatorTestBase extends WebTestBase {
+
+  /**
+   * A user with permission to administer feeds and create content.
+   *
+   * @var \Drupal\user\Entity\User
+   */
+  protected $adminUser;
+
+  /**
+   * Modules to install.
+   *
+   * @var array
+   */
+  public static $modules = array('node', 'aggregator', 'aggregator_test', 'views');
+
+  /**
+   * {@inheritdoc}
+   */
+  protected function setUp() {
+    parent::setUp();
+
+    // Create an Article node type.
+    if ($this->profile != 'standard') {
+      $this->drupalCreateContentType(array('type' => 'article', 'name' => 'Article'));
+    }
+
+    $this->adminUser = $this->drupalCreateUser(array('access administration pages', 'administer news feeds', 'access news feeds', 'create article content'));
+    $this->drupalLogin($this->adminUser);
+  }
+
+  /**
+   * Creates an aggregator feed.
+   *
+   * This method simulates the form submission on path aggregator/sources/add.
+   *
+   * @param string $feed_url
+   *   (optional) If given, feed will be created with this URL, otherwise
+   *   /rss.xml will be used. Defaults to NULL.
+   * @param array $edit
+   *   Array with additional form fields.
+   *
+   * @return \Drupal\aggregator\FeedInterface
+   *   Full feed object if possible.
+   *
+   * @see getFeedEditArray()
+   */
+  public function createFeed($feed_url = NULL, array $edit = array()) {
+    $edit = $this->getFeedEditArray($feed_url, $edit);
+    $this->drupalPostForm('aggregator/sources/add', $edit, t('Save'));
+    $this->assertRaw(t('The feed %name has been added.', array('%name' => $edit['title[0][value]'])), format_string('The feed !name has been added.', array('!name' => $edit['title[0][value]'])));
+
+    $fid = db_query("SELECT fid FROM {aggregator_feed} WHERE title = :title AND url = :url", array(':title' => $edit['title[0][value]'], ':url' => $edit['url[0][value]']))->fetchField();
+    $this->assertTrue(!empty($fid), 'The feed found in database.');
+    return Feed::load($fid);
+  }
+
+  /**
+   * Deletes an aggregator feed.
+   *
+   * @param \Drupal\aggregator\FeedInterface $feed
+   *   Feed object representing the feed.
+   */
+  public function deleteFeed(FeedInterface $feed) {
+    $this->drupalPostForm('aggregator/sources/' . $feed->id() . '/delete', array(), t('Delete'));
+    $this->assertRaw(t('The feed %title has been deleted.', array('%title' => $feed->label())), 'Feed deleted successfully.');
+  }
+
+  /**
+   * Returns a randomly generated feed edit array.
+   *
+   * @param string $feed_url
+   *   (optional) If given, feed will be created with this URL, otherwise
+   *   /rss.xml will be used. Defaults to NULL.
+   * @param array $edit
+   *   Array with additional form fields.
+   *
+   * @return array
+   *   A feed array.
+   */
+  public function getFeedEditArray($feed_url = NULL, array $edit = array()) {
+    $feed_name = $this->randomMachineName(10);
+    if (!$feed_url) {
+      $feed_url = \Drupal::url('view.frontpage.feed_1', array(), array(
+        'query' => array('feed' => $feed_name),
+        'absolute' => TRUE,
+      ));
+    }
+    $edit += array(
+      'title[0][value]' => $feed_name,
+      'url[0][value]' => $feed_url,
+      'refresh' => '900',
+    );
+    return $edit;
+  }
+
+  /**
+   * Returns a randomly generated feed edit object.
+   *
+   * @param string $feed_url
+   *   (optional) If given, feed will be created with this URL, otherwise
+   *   /rss.xml will be used. Defaults to NULL.
+   * @param array $values
+   *   (optional) Default values to initialize object properties with.
+   *
+   * @return \Drupal\aggregator\FeedInterface
+   *   A feed object.
+   */
+  public function getFeedEditObject($feed_url = NULL, array $values = array()) {
+    $feed_name = $this->randomMachineName(10);
+    if (!$feed_url) {
+      $feed_url = \Drupal::url('view.frontpage.feed_1', array(
+        'query' => array('feed' => $feed_name),
+        'absolute' => TRUE,
+      ));
+    }
+    $values += array(
+      'title' => $feed_name,
+      'url' => $feed_url,
+      'refresh' => '900',
+    );
+    return entity_create('aggregator_feed', $values);
+  }
+
+  /**
+   * Returns the count of the randomly created feed array.
+   *
+   * @return int
+   *   Number of feed items on default feed created by createFeed().
+   */
+  public function getDefaultFeedItemCount() {
+    // Our tests are based off of rss.xml, so let's find out how many elements should be related.
+    $feed_count = db_query_range('SELECT COUNT(DISTINCT nid) FROM {node_field_data} n WHERE n.promote = 1 AND n.status = 1', 0, $this->config('system.rss')->get('items.limit'))->fetchField();
+    return $feed_count > 10 ? 10 : $feed_count;
+  }
+
+  /**
+   * Updates the feed items.
+   *
+   * This method simulates a click to
+   * admin/config/services/aggregator/update/$fid.
+   *
+   * @param \Drupal\aggregator\FeedInterface $feed
+   *   Feed object representing the feed.
+   * @param int|null $expected_count
+   *   Expected number of feed items. If omitted no check will happen.
+   */
+  public function updateFeedItems(FeedInterface $feed, $expected_count = NULL) {
+    // First, let's ensure we can get to the rss xml.
+    $this->drupalGet($feed->getUrl());
+    $this->assertResponse(200, format_string('!url is reachable.', array('!url' => $feed->getUrl())));
+
+    // Attempt to access the update link directly without an access token.
+    $this->drupalGet('admin/config/services/aggregator/update/' . $feed->id());
+    $this->assertResponse(403);
+
+    // Refresh the feed (simulated link click).
+    $this->drupalGet('admin/config/services/aggregator');
+    $this->clickLink('Update items');
+
+    // Ensure we have the right number of items.
+    $result = db_query('SELECT iid FROM {aggregator_item} WHERE fid = :fid', array(':fid' => $feed->id()));
+    $feed->items = array();
+    foreach ($result as $item) {
+      $feed->items[] = $item->iid;
+    }
+
+    if ($expected_count !== NULL) {
+      $feed->item_count = count($feed->items);
+      $this->assertEqual($expected_count, $feed->item_count, format_string('Total items in feed equal to the total items in database (!val1 != !val2)', array('!val1' => $expected_count, '!val2' => $feed->item_count)));
+    }
+  }
+
+  /**
+   * Confirms an item removal from a feed.
+   *
+   * @param \Drupal\aggregator\FeedInterface $feed
+   *   Feed object representing the feed.
+   */
+  public function deleteFeedItems(FeedInterface $feed) {
+    $this->drupalPostForm('admin/config/services/aggregator/delete/' . $feed->id(), array(), t('Delete items'));
+    $this->assertRaw(t('The news items from %title have been deleted.', array('%title' => $feed->label())), 'Feed items deleted.');
+  }
+
+  /**
+   * Adds and deletes feed items and ensure that the count is zero.
+   *
+   * @param \Drupal\aggregator\FeedInterface $feed
+   *   Feed object representing the feed.
+   * @param int $expected_count
+   *   Expected number of feed items.
+   */
+  public function updateAndDelete(FeedInterface $feed, $expected_count) {
+    $this->updateFeedItems($feed, $expected_count);
+    $count = db_query('SELECT COUNT(*) FROM {aggregator_item} WHERE fid = :fid', array(':fid' => $feed->id()))->fetchField();
+    $this->assertTrue($count);
+    $this->deleteFeedItems($feed);
+    $count = db_query('SELECT COUNT(*) FROM {aggregator_item} WHERE fid = :fid', array(':fid' => $feed->id()))->fetchField();
+    $this->assertTrue($count == 0);
+  }
+
+  /**
+   * Checks whether the feed name and URL are unique.
+   *
+   * @param string $feed_name
+   *   String containing the feed name to check.
+   * @param string $feed_url
+   *   String containing the feed url to check.
+   *
+   * @return bool
+   *   TRUE if feed is unique.
+   */
+  public function uniqueFeed($feed_name, $feed_url) {
+    $result = db_query("SELECT COUNT(*) FROM {aggregator_feed} WHERE title = :title AND url = :url", array(':title' => $feed_name, ':url' => $feed_url))->fetchField();
+    return (1 == $result);
+  }
+
+  /**
+   * Creates a valid OPML file from an array of feeds.
+   *
+   * @param array $feeds
+   *   An array of feeds.
+   *
+   * @return string
+   *   Path to valid OPML file.
+   */
+  public function getValidOpml(array $feeds) {
+    // Properly escape URLs so that XML parsers don't choke on them.
+    foreach ($feeds as &$feed) {
+      $feed['url[0][value]'] = htmlspecialchars($feed['url[0][value]']);
+    }
+    /**
+     * Does not have an XML declaration, must pass the parser.
+     */
+    $opml = <<<EOF
+<opml version="1.0">
+  <head></head>
+  <body>
+    <!-- First feed to be imported. -->
+    <outline text="{$feeds[0]['title[0][value]']}" xmlurl="{$feeds[0]['url[0][value]']}" />
+
+    <!-- Second feed. Test string delimitation and attribute order. -->
+    <outline xmlurl='{$feeds[1]['url[0][value]']}' text='{$feeds[1]['title[0][value]']}'/>
+
+    <!-- Test for duplicate URL and title. -->
+    <outline xmlurl="{$feeds[0]['url[0][value]']}" text="Duplicate URL"/>
+    <outline xmlurl="http://duplicate.title" text="{$feeds[1]['title[0][value]']}"/>
+
+    <!-- Test that feeds are only added with required attributes. -->
+    <outline text="{$feeds[2]['title[0][value]']}" />
+    <outline xmlurl="{$feeds[2]['url[0][value]']}" />
+  </body>
+</opml>
+EOF;
+
+    $path = 'public://valid-opml.xml';
+    return file_unmanaged_save_data($opml, $path);
+  }
+
+  /**
+   * Creates an invalid OPML file.
+   *
+   * @return string
+   *   Path to invalid OPML file.
+   */
+  public function getInvalidOpml() {
+    $opml = <<<EOF
+<opml>
+  <invalid>
+</opml>
+EOF;
+
+    $path = 'public://invalid-opml.xml';
+    return file_unmanaged_save_data($opml, $path);
+  }
+
+  /**
+   * Creates a valid but empty OPML file.
+   *
+   * @return string
+   *   Path to empty OPML file.
+   */
+  public function getEmptyOpml() {
+    $opml = <<<EOF
+<?xml version="1.0" encoding="utf-8"?>
+<opml version="1.0">
+  <head></head>
+  <body>
+    <outline text="Sample text" />
+    <outline text="Sample text" url="Sample URL" />
+  </body>
+</opml>
+EOF;
+
+    $path = 'public://empty-opml.xml';
+    return file_unmanaged_save_data($opml, $path);
+  }
+
+  /**
+   * Returns a example RSS091 feed.
+   *
+   * @return string
+   *   Path to the feed.
+   */
+  public function getRSS091Sample() {
+    return $GLOBALS['base_url'] . '/' . drupal_get_path('module', 'aggregator') . '/tests/modules/aggregator_test/aggregator_test_rss091.xml';
+  }
+
+  /**
+   * Returns a example Atom feed.
+   *
+   * @return string
+   *   Path to the feed.
+   */
+  public function getAtomSample() {
+    // The content of this sample ATOM feed is based directly off of the
+    // example provided in RFC 4287.
+    return $GLOBALS['base_url'] . '/' . drupal_get_path('module', 'aggregator') . '/tests/modules/aggregator_test/aggregator_test_atom.xml';
+  }
+
+  /**
+   * Returns a example feed.
+   *
+   * @return string
+   *   Path to the feed.
+   */
+  public function getHtmlEntitiesSample() {
+    return $GLOBALS['base_url'] . '/' . drupal_get_path('module', 'aggregator') . '/tests/modules/aggregator_test/aggregator_test_title_entities.xml';
+  }
+
+  /**
+   * Creates sample article nodes.
+   *
+   * @param int $count
+   *   (optional) The number of nodes to generate. Defaults to five.
+   */
+  public function createSampleNodes($count = 5) {
+    // Post $count article nodes.
+    for ($i = 0; $i < $count; $i++) {
+      $edit = array();
+      $edit['title[0][value]'] = $this->randomMachineName();
+      $edit['body[0][value]'] = $this->randomMachineName();
+      $this->drupalPostForm('node/add/article', $edit, t('Save'));
+    }
+  }
+
+  /**
+   * Enable the plugins coming with aggregator_test module.
+   */
+  public function enableTestPlugins() {
+    $this->config('aggregator.settings')
+      ->set('fetcher', 'aggregator_test_fetcher')
+      ->set('parser', 'aggregator_test_parser')
+      ->set('processors', array(
+        'aggregator_test_processor' => 'aggregator_test_processor',
+        'aggregator' => 'aggregator',
+      ))
+      ->save();
+  }
+}

core/modules/aggregator/src/Tests/AggregatorTitleTest.php

@@ -0,0 +1,93 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\aggregator\Tests\AggregatorTitleTest.
+ */
+
+namespace Drupal\aggregator\Tests;
+
+use Drupal\aggregator\Entity\Feed;
+use Drupal\aggregator\Entity\Item;
+use Drupal\simpletest\KernelTestBase;
+
+
+/**
+ * Tests the aggregator_title formatter.
+ *
+ * @group field
+ */
+class AggregatorTitleTest extends KernelTestBase {
+
+  /**
+   * Modules to enable.
+   *
+   * @var array
+   */
+  public static $modules = array('file', 'field', 'options', 'aggregator', 'entity_reference');
+
+  /**
+   * The field name that is tested.
+   *
+   * @var string
+   */
+  protected $fieldName;
+
+  /**
+   * {@inheritdoc}
+   */
+  protected function setUp() {
+    parent::setUp();
+
+    $this->installConfig(['field']);
+    $this->installEntitySchema('aggregator_feed');
+    $this->installEntitySchema('aggregator_item');
+
+    $this->fieldName = 'title';
+  }
+
+  /*
+   * Tests the formatter output.
+   */
+  public function testStringFormatter() {
+    // Create an aggregator feed.
+    $aggregator_feed = Feed::create([
+      'title' => 'testing title',
+      'url' => 'http://www.example.com',
+    ]);
+    $aggregator_feed->save();
+
+    // Create an aggregator feed item.
+    $aggregator_item = Item::create([
+      'title' => 'test title',
+      'fid' => $aggregator_feed->id(),
+      'link' => 'http://www.example.com',
+      ]);
+    $aggregator_item->save();
+
+    // Verify aggregator feed title with and without links.
+    $build = $aggregator_feed->{$this->fieldName}->view(['type' => 'aggregator_title', 'settings' => ['display_as_link' => TRUE]]);
+    $result = $this->render($build);
+
+    $this->assertTrue(strpos($result, 'testing title'));
+    $this->assertTrue(strpos($result, 'href="' . $aggregator_feed->getUrl()) . '"');
+
+    $build = $aggregator_feed->{$this->fieldName}->view(['type' => 'aggregator_title', 'settings' => ['display_as_link' => FALSE]]);
+    $result = $this->render($build);
+    $this->assertTrue(strpos($result, 'testing title') === 0);
+    $this->assertTrue(strpos($result, $aggregator_feed->getUrl()) === FALSE);
+
+    // Verify aggregator item title with and without links.
+    $build = $aggregator_item->{$this->fieldName}->view(['type' => 'aggregator_title', 'settings' => ['display_as_link' =>TRUE]]);
+    $result = $this->render($build);
+
+    $this->assertTrue(strpos($result, 'test title'));
+    $this->assertTrue(strpos($result, 'href="' . $aggregator_item->getLink()) . '"');
+
+    $build = $aggregator_item->{$this->fieldName}->view(['type' => 'aggregator_title', 'settings' => ['display_as_link' => FALSE]]);
+    $result = $this->render($build);
+    $this->assertTrue(strpos($result, 'test title') === 0);
+    $this->assertTrue(strpos($result, $aggregator_item->getLink()) === FALSE);
+  }
+
+}

core/modules/aggregator/src/Tests/DeleteFeedItemTest.php

@@ -0,0 +1,44 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\aggregator\Tests\DeleteFeedItemTest.
+ */
+
+namespace Drupal\aggregator\Tests;
+
+/**
+ * Delete feed items from a feed.
+ *
+ * @group aggregator
+ */
+class DeleteFeedItemTest extends AggregatorTestBase {
+  /**
+   * Tests running "delete items" from 'admin/config/services/aggregator' page.
+   */
+  public function testDeleteFeedItem() {
+    // Create a bunch of test feeds.
+    $feed_urls = array();
+    // No last-modified, no etag.
+    $feed_urls[] = \Drupal::url('aggregator_test.feed', array(), array('absolute' => TRUE));
+    // Last-modified, but no etag.
+    $feed_urls[] = \Drupal::url('aggregator_test.feed', array('use_last_modified' => 1), array('absolute' => TRUE));
+    // No Last-modified, but etag.
+    $feed_urls[] = \Drupal::url('aggregator_test.feed', array('use_last_modified' => 0, 'use_etag' => 1), array('absolute' => TRUE));
+    // Last-modified and etag.
+    $feed_urls[] = \Drupal::url('aggregator_test.feed', array('use_last_modified' => 1, 'use_etag' => 1), array('absolute' => TRUE));
+
+    foreach ($feed_urls as $feed_url) {
+      $feed = $this->createFeed($feed_url);
+      // Update and delete items two times in a row to make sure that removal
+      // resets all 'modified' information (modified, etag, hash) and allows for
+      // immediate update. There's 8 items in the feed, but one has an empty
+      // title and is skipped.
+      $this->updateAndDelete($feed, 7);
+      $this->updateAndDelete($feed, 7);
+      $this->updateAndDelete($feed, 7);
+      // Delete feed.
+      $this->deleteFeed($feed);
+    }
+  }
+}

core/modules/aggregator/src/Tests/DeleteFeedTest.php

@@ -0,0 +1,55 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\aggregator\Tests\DeleteFeedTest.
+ */
+
+namespace Drupal\aggregator\Tests;
+
+/**
+ * Delete feed test.
+ *
+ * @group aggregator
+ */
+class DeleteFeedTest extends AggregatorTestBase {
+
+  /**
+   * Modules to install.
+   *
+   * @var array
+   */
+  public static $modules = array('block');
+
+  /**
+   * Deletes a feed and ensures that all of its services are deleted.
+   */
+  public function testDeleteFeed() {
+    $feed1 = $this->createFeed();
+    $feed2 = $this->createFeed();
+
+    // Place a block for both feeds.
+    $block = $this->drupalPlaceBlock('aggregator_feed_block');
+    $block->getPlugin()->setConfigurationValue('feed', $feed1->id());
+    $block->save();
+    $block2 = $this->drupalPlaceBlock('aggregator_feed_block');
+    $block2->getPlugin()->setConfigurationValue('feed', $feed2->id());
+    $block2->save();
+
+    // Delete feed.
+    $this->deleteFeed($feed1);
+    $this->assertText($feed2->label());
+    $block_storage = $this->container->get('entity.manager')->getStorage('block');
+    $this->assertNull($block_storage->load($block->id()), 'Block for the deleted feed was deleted.');
+    $this->assertEqual($block2->id(), $block_storage->load($block2->id())->id(), 'Block for not deleted feed still exists.');
+
+    // Check feed source.
+    $this->drupalGet('aggregator/sources/' . $feed1->id());
+    $this->assertResponse(404, 'Deleted feed source does not exists.');
+
+    // Check database for feed.
+    $result = db_query("SELECT COUNT(*) FROM {aggregator_feed} WHERE title = :title AND url = :url", array(':title' => $feed1->label(), ':url' => $feed1->getUrl()))->fetchField();
+    $this->assertFalse($result, 'Feed not found in database');
+  }
+
+}

core/modules/aggregator/src/Tests/FeedCacheTagsTest.php

@@ -0,0 +1,57 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\aggregator\Tests\FeedCacheTagsTest.
+ */
+
+namespace Drupal\aggregator\Tests;
+
+use Drupal\aggregator\Entity\Feed;
+use Drupal\system\Tests\Entity\EntityWithUriCacheTagsTestBase;
+use Drupal\user\Entity\Role;
+use Drupal\user\RoleInterface;
+
+/**
+ * Tests the Feed entity's cache tags.
+ *
+ * @group aggregator
+ */
+class FeedCacheTagsTest extends EntityWithUriCacheTagsTestBase {
+
+  /**
+   * {@inheritdoc}
+   */
+  public static $modules = array('aggregator');
+
+  /**
+   * {@inheritdoc}
+   */
+  protected function setUp() {
+    parent::setUp();
+
+    // Give anonymous users permission to access feeds, so that we can verify
+    // the cache tags of cached versions of feeds.
+    $user_role = Role::load(RoleInterface::ANONYMOUS_ID);
+    $user_role->grantPermission('access news feeds');
+    $user_role->save();
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  protected function createEntity() {
+    // Create a "Llama" feed.
+    $feed = Feed::create(array(
+      'title' => 'Llama',
+      'url' => 'https://www.drupal.org/',
+      'refresh' => 900,
+      'checked' => 1389919932,
+      'description' => 'Drupal.org',
+    ));
+    $feed->save();
+
+    return $feed;
+  }
+
+}

core/modules/aggregator/src/Tests/FeedFetcherPluginTest.php

@@ -0,0 +1,48 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\aggregator\Tests\FeedFetcherPluginTest.
+ */
+
+namespace Drupal\aggregator\Tests;
+
+/**
+ * Tests the fetcher plugins functionality and discoverability.
+ *
+ * @group aggregator
+ *
+ * @see \Drupal\aggregator_test\Plugin\aggregator\fetcher\TestFetcher.
+ */
+class FeedFetcherPluginTest extends AggregatorTestBase {
+
+  /**
+   * {@inheritdoc}
+   */
+  protected function setUp() {
+    parent::setUp();
+    // Enable test plugins.
+    $this->enableTestPlugins();
+    // Create some nodes.
+    $this->createSampleNodes();
+  }
+
+  /**
+   * Test fetching functionality.
+   */
+  public function testfetch() {
+    // Create feed with local url.
+    $feed = $this->createFeed();
+    $this->updateFeedItems($feed);
+    $this->assertFalse(empty($feed->items));
+
+    // Delete items and restore checked property to 0.
+    $this->deleteFeedItems($feed);
+    // Change its name and try again.
+    $feed->setTitle('Do not fetch');
+    $feed->save();
+    $this->updateFeedItems($feed);
+    // Fetch should fail due to feed name.
+    $this->assertTrue(empty($feed->items));
+  }
+}

core/modules/aggregator/src/Tests/FeedLanguageTest.php

@@ -0,0 +1,89 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\aggregator\Tests\FeedLanguageTest.
+ */
+
+namespace Drupal\aggregator\Tests;
+
+use Drupal\language\Entity\ConfigurableLanguage;
+
+/**
+ * Tests aggregator feeds in multiple languages.
+ *
+ * @group aggregator
+ */
+class FeedLanguageTest extends AggregatorTestBase {
+
+  /**
+   * Modules to install.
+   *
+   * @var array
+   */
+  public static $modules = array('language');
+
+  /**
+   * List of langcodes.
+   *
+   * @var string[]
+   */
+  protected $langcodes = array();
+
+  /**
+   * {@inheritdoc}
+   */
+  protected function setUp() {
+    parent::setUp();
+
+    // Create test languages.
+    $this->langcodes = array(ConfigurableLanguage::load('en'));
+    for ($i = 1; $i < 3; ++$i) {
+      $language = ConfigurableLanguage::create(array(
+        'id' => 'l' . $i,
+        'label' => $this->randomString(),
+      ));
+      $language->save();
+      $this->langcodes[$i] = $language->id();
+    }
+  }
+
+  /**
+   * Tests creation of feeds with a language.
+   */
+  public function testFeedLanguage() {
+    $admin_user = $this->drupalCreateUser(['administer languages', 'access administration pages', 'administer news feeds', 'access news feeds', 'create article content']);
+    $this->drupalLogin($admin_user);
+
+    // Enable language selection for feeds.
+    $edit['entity_types[aggregator_feed]'] = TRUE;
+    $edit['settings[aggregator_feed][aggregator_feed][settings][language][language_alterable]'] = TRUE;
+
+    $this->drupalPostForm('admin/config/regional/content-language', $edit, t('Save configuration'));
+
+    /** @var \Drupal\aggregator\FeedInterface[] $feeds */
+    $feeds = array();
+    // Create feeds.
+    $feeds[1] = $this->createFeed(NULL, array('langcode[0][value]' => $this->langcodes[1]));
+    $feeds[2] = $this->createFeed(NULL, array('langcode[0][value]' => $this->langcodes[2]));
+
+    // Make sure that the language has been assigned.
+    $this->assertEqual($feeds[1]->language()->getId(), $this->langcodes[1]);
+    $this->assertEqual($feeds[2]->language()->getId(), $this->langcodes[2]);
+
+    // Create example nodes to create feed items from and then update the feeds.
+    $this->createSampleNodes();
+    $this->cronRun();
+
+    // Loop over the created feed items and verify that their language matches
+    // the one from the feed.
+    foreach ($feeds as $feed) {
+      /** @var \Drupal\aggregator\ItemInterface[] $items */
+      $items = entity_load_multiple_by_properties('aggregator_item', array('fid' => $feed->id()));
+      $this->assertTrue(count($items) > 0, 'Feed items were created.');
+      foreach ($items as $item) {
+        $this->assertEqual($item->language()->getId(), $feed->language()->getId());
+      }
+    }
+  }
+}

core/modules/aggregator/src/Tests/FeedParserTest.php

@@ -0,0 +1,111 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\aggregator\Tests\FeedParserTest.
+ */
+
+namespace Drupal\aggregator\Tests;
+
+use Drupal\Core\Url;
+use Zend\Feed\Reader\Reader;
+
+/**
+ * Tests the built-in feed parser with valid feed samples.
+ *
+ * @group aggregator
+ */
+class FeedParserTest extends AggregatorTestBase {
+
+  /**
+   * {@inheritdoc}
+   */
+  protected function setUp() {
+    parent::setUp();
+    // Do not delete old aggregator items during these tests, since our sample
+    // feeds have hardcoded dates in them (which may be expired when this test
+    // is run).
+    $this->config('aggregator.settings')->set('items.expire', AGGREGATOR_CLEAR_NEVER)->save();
+    // Reset any reader cache between tests.
+    Reader::reset();
+    // Set our bridge extension manager to Zend Feed.
+    $bridge = $this->container->get('feed.bridge.reader');
+    Reader::setExtensionManager($bridge);
+  }
+
+  /**
+   * Tests a feed that uses the RSS 0.91 format.
+   */
+  public function testRSS091Sample() {
+    $feed = $this->createFeed($this->getRSS091Sample());
+    $feed->refreshItems();
+    $this->drupalGet('aggregator/sources/' . $feed->id());
+    $this->assertResponse(200, format_string('Feed %name exists.', array('%name' => $feed->label())));
+    $this->assertText('First example feed item title');
+    $this->assertLinkByHref('http://example.com/example-turns-one');
+    $this->assertText('First example feed item description.');
+    $this->assertRaw('<img src="http://example.com/images/druplicon.png"');
+
+    // Several additional items that include elements over 255 characters.
+    $this->assertRaw("Second example feed item title.");
+    $this->assertText('Long link feed item title');
+    $this->assertText('Long link feed item description');
+    $this->assertLinkByHref('http://example.com/tomorrow/and/tomorrow/and/tomorrow/creeps/in/this/petty/pace/from/day/to/day/to/the/last/syllable/of/recorded/time/and/all/our/yesterdays/have/lighted/fools/the/way/to/dusty/death/out/out/brief/candle/life/is/but/a/walking/shadow/a/poor/player/that/struts/and/frets/his/hour/upon/the/stage/and/is/heard/no/more/it/is/a/tale/told/by/an/idiot/full/of/sound/and/fury/signifying/nothing');
+    $this->assertText('Long author feed item title');
+    $this->assertText('Long author feed item description');
+    $this->assertLinkByHref('http://example.com/long/author');
+  }
+
+  /**
+   * Tests a feed that uses the Atom format.
+   */
+  public function testAtomSample() {
+    $feed = $this->createFeed($this->getAtomSample());
+    $feed->refreshItems();
+    $this->drupalGet('aggregator/sources/' . $feed->id());
+    $this->assertResponse(200, format_string('Feed %name exists.', array('%name' => $feed->label())));
+    $this->assertText('Atom-Powered Robots Run Amok');
+    $this->assertLinkByHref('http://example.org/2003/12/13/atom03');
+    $this->assertText('Some text.');
+    $this->assertEqual('urn:uuid:1225c695-cfb8-4ebb-aaaa-80da344efa6a', db_query('SELECT guid FROM {aggregator_item} WHERE link = :link', array(':link' => 'http://example.org/2003/12/13/atom03'))->fetchField(), 'Atom entry id element is parsed correctly.');
+  }
+
+  /**
+   * Tests a feed that uses HTML entities in item titles.
+   */
+  public function testHtmlEntitiesSample() {
+    $feed = $this->createFeed($this->getHtmlEntitiesSample());
+    $feed->refreshItems();
+    $this->drupalGet('aggregator/sources/' . $feed->id());
+    $this->assertResponse(200, format_string('Feed %name exists.', array('%name' => $feed->label())));
+    $this->assertRaw("Quote&quot; Amp&amp;");
+  }
+
+  /**
+   * Tests that a redirected feed is tracked to its target.
+   */
+  public function testRedirectFeed() {
+    $redirect_url = Url::fromRoute('aggregator_test.redirect')->setAbsolute()->toString();
+    $feed = entity_create('aggregator_feed', array('url' => $redirect_url, 'title' => $this->randomMachineName()));
+    $feed->save();
+    $feed->refreshItems();
+
+    // Make sure that the feed URL was updated correctly.
+    $this->assertEqual($feed->getUrl(), \Drupal::url('aggregator_test.feed', array(), array('absolute' => TRUE)));
+  }
+
+  /**
+   * Tests error handling when an invalid feed is added.
+   */
+  public function testInvalidFeed() {
+    // Simulate a typo in the URL to force a curl exception.
+    $invalid_url = 'http:/www.drupal.org';
+    $feed = entity_create('aggregator_feed', array('url' => $invalid_url, 'title' => $this->randomMachineName()));
+    $feed->save();
+
+    // Update the feed. Use the UI to be able to check the message easily.
+    $this->drupalGet('admin/config/services/aggregator');
+    $this->clickLink(t('Update items'));
+    $this->assertRaw(t('The feed from %title seems to be broken because of error', array('%title' => $feed->label())));
+  }
+}

core/modules/aggregator/src/Tests/FeedProcessorPluginTest.php

@@ -0,0 +1,70 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\aggregator\Tests\FeedProcessorPluginTest.
+ */
+
+namespace Drupal\aggregator\Tests;
+
+use Drupal\aggregator\Entity\Feed;
+use Drupal\aggregator\Entity\Item;
+
+/**
+ * Tests the processor plugins functionality and discoverability.
+ *
+ * @group aggregator
+ *
+ * @see \Drupal\aggregator_test\Plugin\aggregator\processor\TestProcessor.
+ */
+class FeedProcessorPluginTest extends AggregatorTestBase {
+
+  /**
+   * {@inheritdoc}
+   */
+  protected function setUp() {
+    parent::setUp();
+    // Enable test plugins.
+    $this->enableTestPlugins();
+    // Create some nodes.
+    $this->createSampleNodes();
+  }
+
+  /**
+   * Test processing functionality.
+   */
+  public function testProcess() {
+    $feed = $this->createFeed();
+    $this->updateFeedItems($feed);
+    foreach ($feed->items as $iid) {
+      $item = Item::load($iid);
+      $this->assertTrue(strpos($item->label(), 'testProcessor') === 0);
+    }
+  }
+
+  /**
+   * Test deleting functionality.
+   */
+  public function testDelete() {
+    $feed = $this->createFeed();
+    $this->updateAndDelete($feed, NULL);
+    // Make sure the feed title is changed.
+    $entities = entity_load_multiple_by_properties('aggregator_feed', array('description' => $feed->description->value));
+    $this->assertTrue(empty($entities));
+  }
+
+  /**
+   * Test post-processing functionality.
+   */
+  public function testPostProcess() {
+    $feed = $this->createFeed(NULL, array('refresh' => 1800));
+    $this->updateFeedItems($feed);
+    $feed_id = $feed->id();
+    // Reset entity cache manually.
+    \Drupal::entityManager()->getStorage('aggregator_feed')->resetCache(array($feed_id));
+    // Reload the feed to get new values.
+    $feed = Feed::load($feed_id);
+    // Make sure its refresh rate doubled.
+    $this->assertEqual($feed->getRefreshRate(), 3600);
+  }
+}

core/modules/aggregator/src/Tests/FeedValidationTest.php

@@ -0,0 +1,72 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\aggregator\Tests\FeedValidationTest.
+ */
+
+namespace Drupal\aggregator\Tests;
+
+use Drupal\aggregator\Entity\Feed;
+use Drupal\system\Tests\Entity\EntityUnitTestBase;
+
+/**
+ * Tests feed validation constraints.
+ *
+ * @group aggregator
+ */
+class FeedValidationTest extends EntityUnitTestBase {
+
+  /**
+   * Modules to install.
+   *
+   * @var array
+   */
+  public static $modules = array('aggregator', 'options');
+
+  /**
+   * {@inheritdoc}
+   */
+  protected function setUp() {
+    parent::setUp();
+    $this->installEntitySchema('aggregator_feed');
+  }
+
+  /**
+   * Tests the feed validation constraints.
+   */
+  public function testValidation() {
+    // Add feed.
+    $feed = Feed::create([
+      'title' => 'Feed 1',
+      'url' => 'https://www.drupal.org/planet/rss.xml',
+      'refresh' => 900,
+    ]);
+
+    $violations = $feed->validate();
+    $this->assertEqual(count($violations), 0);
+
+    $feed->save();
+
+    // Add another feed.
+    /* @var \Drupal\aggregator\FeedInterface $feed */
+    $feed = Feed::create([
+      'title' => 'Feed 1',
+      'url' => 'https://www.drupal.org/planet/rss.xml',
+      'refresh' => 900,
+    ]);
+
+    $violations = $feed->validate();
+
+    $this->assertEqual(count($violations), 2);
+    $this->assertEqual($violations[0]->getPropertyPath(), 'title');
+    $this->assertEqual($violations[0]->getMessage(), t('A feed named %value already exists. Enter a unique title.', [
+      '%value' => $feed->label(),
+    ]));
+    $this->assertEqual($violations[1]->getPropertyPath(), 'url');
+    $this->assertEqual($violations[1]->getMessage(), t('A feed with this URL %value already exists. Enter a unique URL.', [
+      '%value' => $feed->getUrl(),
+    ]));
+  }
+
+}

core/modules/aggregator/src/Tests/ImportOpmlTest.php

@@ -0,0 +1,128 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\aggregator\Tests\ImportOpmlTest.
+ */
+
+namespace Drupal\aggregator\Tests;
+
+/**
+ * Tests OPML import.
+ *
+ * @group aggregator
+ */
+class ImportOpmlTest extends AggregatorTestBase {
+
+  /**
+   * Modules to install.
+   *
+   * @var array
+   */
+  public static $modules = array('block', 'help');
+
+  /**
+   * {@inheritdoc}
+   */
+  protected function setUp() {
+    parent::setUp();
+
+    $admin_user = $this->drupalCreateUser(array('administer news feeds', 'access news feeds', 'create article content', 'administer blocks'));
+    $this->drupalLogin($admin_user);
+  }
+
+  /**
+   * Opens OPML import form.
+   */
+  public function openImportForm() {
+    // Enable the help block.
+    $this->drupalPlaceBlock('help_block', array('region' => 'help'));
+
+    $this->drupalGet('admin/config/services/aggregator/add/opml');
+    $this->assertText('A single OPML document may contain many feeds.', 'Found OPML help text.');
+    $this->assertField('files[upload]', 'Found file upload field.');
+    $this->assertField('remote', 'Found Remote URL field.');
+    $this->assertField('refresh', '', 'Found Refresh field.');
+  }
+
+  /**
+   * Submits form filled with invalid fields.
+   */
+  public function validateImportFormFields() {
+    $before = db_query('SELECT COUNT(*) FROM {aggregator_feed}')->fetchField();
+
+    $edit = array();
+    $this->drupalPostForm('admin/config/services/aggregator/add/opml', $edit, t('Import'));
+    $this->assertRaw(t('<em>Either</em> upload a file or enter a URL.'), 'Error if no fields are filled.');
+
+    $path = $this->getEmptyOpml();
+    $edit = array(
+      'files[upload]' => $path,
+      'remote' => file_create_url($path),
+    );
+    $this->drupalPostForm('admin/config/services/aggregator/add/opml', $edit, t('Import'));
+    $this->assertRaw(t('<em>Either</em> upload a file or enter a URL.'), 'Error if both fields are filled.');
+
+    $edit = array('remote' => 'invalidUrl://empty');
+    $this->drupalPostForm('admin/config/services/aggregator/add/opml', $edit, t('Import'));
+    $this->assertText(t('The URL invalidUrl://empty is not valid.'), 'Error if the URL is invalid.');
+
+    $after = db_query('SELECT COUNT(*) FROM {aggregator_feed}')->fetchField();
+    $this->assertEqual($before, $after, 'No feeds were added during the three last form submissions.');
+  }
+
+  /**
+   * Submits form with invalid, empty, and valid OPML files.
+   */
+  protected function submitImportForm() {
+    $before = db_query('SELECT COUNT(*) FROM {aggregator_feed}')->fetchField();
+
+    $form['files[upload]'] = $this->getInvalidOpml();
+    $this->drupalPostForm('admin/config/services/aggregator/add/opml', $form, t('Import'));
+    $this->assertText(t('No new feed has been added.'), 'Attempting to upload invalid XML.');
+
+    $edit = array('remote' => file_create_url($this->getEmptyOpml()));
+    $this->drupalPostForm('admin/config/services/aggregator/add/opml', $edit, t('Import'));
+    $this->assertText(t('No new feed has been added.'), 'Attempting to load empty OPML from remote URL.');
+
+    $after = db_query('SELECT COUNT(*) FROM {aggregator_feed}')->fetchField();
+    $this->assertEqual($before, $after, 'No feeds were added during the two last form submissions.');
+
+    db_delete('aggregator_feed')->execute();
+
+    $feeds[0] = $this->getFeedEditArray();
+    $feeds[1] = $this->getFeedEditArray();
+    $feeds[2] = $this->getFeedEditArray();
+    $edit = array(
+      'files[upload]' => $this->getValidOpml($feeds),
+      'refresh'       => '900',
+    );
+    $this->drupalPostForm('admin/config/services/aggregator/add/opml', $edit, t('Import'));
+    $this->assertRaw(t('A feed with the URL %url already exists.', array('%url' => $feeds[0]['url[0][value]'])), 'Verifying that a duplicate URL was identified');
+    $this->assertRaw(t('A feed named %title already exists.', array('%title' => $feeds[1]['title[0][value]'])), 'Verifying that a duplicate title was identified');
+
+    $after = db_query('SELECT COUNT(*) FROM {aggregator_feed}')->fetchField();
+    $this->assertEqual($after, 2, 'Verifying that two distinct feeds were added.');
+
+    $feeds_from_db = db_query("SELECT title, url, refresh FROM {aggregator_feed}");
+    $refresh = TRUE;
+    foreach ($feeds_from_db as $feed) {
+      $title[$feed->url] = $feed->title;
+      $url[$feed->title] = $feed->url;
+      $refresh = $refresh && $feed->refresh == 900;
+    }
+
+    $this->assertEqual($title[$feeds[0]['url[0][value]']], $feeds[0]['title[0][value]'], 'First feed was added correctly.');
+    $this->assertEqual($url[$feeds[1]['title[0][value]']], $feeds[1]['url[0][value]'], 'Second feed was added correctly.');
+    $this->assertTrue($refresh, 'Refresh times are correct.');
+  }
+
+  /**
+   * Tests the import of an OPML file.
+   */
+  public function testOpmlImport() {
+    $this->openImportForm();
+    $this->validateImportFormFields();
+    $this->submitImportForm();
+  }
+}

core/modules/aggregator/src/Tests/ItemCacheTagsTest.php

@@ -0,0 +1,87 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\aggregator\Tests\ItemCacheTagsTest.
+ */
+
+namespace Drupal\aggregator\Tests;
+
+use Drupal\aggregator\Entity\Feed;
+use Drupal\aggregator\Entity\Item;
+use Drupal\system\Tests\Entity\EntityCacheTagsTestBase;
+use Drupal\user\Entity\Role;
+use Drupal\user\RoleInterface;
+
+/**
+ * Tests the Item entity's cache tags.
+ *
+ * @group aggregator
+ */
+class ItemCacheTagsTest extends EntityCacheTagsTestBase {
+
+  /**
+   * {@inheritdoc}
+   */
+  public static $modules = array('aggregator');
+
+  /**
+   * {@inheritdoc}
+   */
+  protected function setUp() {
+    parent::setUp();
+
+    // Give anonymous users permission to access feeds, so that we can verify
+    // the cache tags of cached versions of feed items.
+    $user_role = Role::load(RoleInterface::ANONYMOUS_ID);
+    $user_role->grantPermission('access news feeds');
+    $user_role->save();
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  protected function createEntity() {
+    // Create a "Camelids" feed.
+    $feed = Feed::create(array(
+      'title' => 'Camelids',
+      'url' => 'https://groups.drupal.org/not_used/167169',
+      'refresh' => 900,
+      'checked' => 1389919932,
+      'description' => 'Drupal Core Group feed',
+    ));
+    $feed->save();
+
+    // Create a "Llama" aggregator feed item.
+    $item = Item::create(array(
+      'fid' => $feed->id(),
+      'title' => t('Llama'),
+      'path' => 'https://www.drupal.org/',
+    ));
+    $item->save();
+
+    return $item;
+  }
+
+  /**
+   * Tests that when creating a feed item, the feed tag is invalidated.
+   */
+  public function testEntityCreation() {
+    // Create a cache entry that is tagged with a feed cache tag.
+    \Drupal::cache('render')->set('foo', 'bar', \Drupal\Core\Cache\CacheBackendInterface::CACHE_PERMANENT, $this->entity->getCacheTags());
+
+    // Verify a cache hit.
+    $this->verifyRenderCache('foo', array('aggregator_feed:1'));
+
+    // Now create a feed item in that feed.
+    Item::create(array(
+      'fid' => $this->entity->getFeedId(),
+      'title' => t('Llama 2'),
+      'path' => 'https://groups.drupal.org/',
+    ))->save();
+
+    // Verify a cache miss.
+    $this->assertFalse(\Drupal::cache('render')->get('foo'), 'Creating a new feed item invalidates the cache tag of the feed.');
+  }
+
+}

core/modules/aggregator/src/Tests/UpdateFeedItemTest.php

@@ -0,0 +1,74 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\aggregator\Tests\UpdateFeedItemTest.
+ */
+
+namespace Drupal\aggregator\Tests;
+use Drupal\aggregator\Entity\Feed;
+
+/**
+ * Update feed items from a feed.
+ *
+ * @group aggregator
+ */
+class UpdateFeedItemTest extends AggregatorTestBase {
+  /**
+   * Tests running "update items" from 'admin/config/services/aggregator' page.
+   */
+  public function testUpdateFeedItem() {
+    $this->createSampleNodes();
+
+    // Create a feed and test updating feed items if possible.
+    $feed = $this->createFeed();
+    if (!empty($feed)) {
+      $this->updateFeedItems($feed, $this->getDefaultFeedItemCount());
+      $this->deleteFeedItems($feed);
+    }
+
+    // Delete feed.
+    $this->deleteFeed($feed);
+
+    // Test updating feed items without valid timestamp information.
+    $edit = array(
+      'title[0][value]' => "Feed without publish timestamp",
+      'url[0][value]' => $this->getRSS091Sample(),
+    );
+
+    $this->drupalGet($edit['url[0][value]']);
+    $this->assertResponse(array(200), format_string('URL !url is accessible', array('!url' => $edit['url[0][value]'])));
+
+    $this->drupalPostForm('aggregator/sources/add', $edit, t('Save'));
+    $this->assertRaw(t('The feed %name has been added.', array('%name' => $edit['title[0][value]'])), format_string('The feed !name has been added.', array('!name' => $edit['title[0][value]'])));
+
+    $fid = db_query("SELECT fid FROM {aggregator_feed} WHERE url = :url", array(':url' => $edit['url[0][value]']))->fetchField();
+    $feed = Feed::load($fid);
+
+    $feed->refreshItems();
+    $before = db_query('SELECT timestamp FROM {aggregator_item} WHERE fid = :fid', array(':fid' => $feed->id()))->fetchField();
+
+    // Sleep for 3 second.
+    sleep(3);
+    db_update('aggregator_feed')
+      ->condition('fid', $feed->id())
+      ->fields(array(
+        'checked' => 0,
+        'hash' => '',
+        'etag' => '',
+        'modified' => 0,
+      ))
+      ->execute();
+    $feed->refreshItems();
+
+    $after = db_query('SELECT timestamp FROM {aggregator_item} WHERE fid = :fid', array(':fid' => $feed->id()))->fetchField();
+    $this->assertTrue($before === $after, format_string('Publish timestamp of feed item was not updated (!before === !after)', array('!before' => $before, '!after' => $after)));
+
+    // Make sure updating items works even after uninstalling a module
+    // that provides the selected plugins.
+    $this->enableTestPlugins();
+    $this->container->get('module_installer')->uninstall(array('aggregator_test'));
+    $this->updateFeedItems($feed);
+    $this->assertResponse(200);
+  }
+}

core/modules/aggregator/src/Tests/UpdateFeedTest.php

@@ -0,0 +1,50 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\aggregator\Tests\UpdateFeedTest.
+ */
+
+namespace Drupal\aggregator\Tests;
+
+/**
+ * Update feed test.
+ *
+ * @group aggregator
+ */
+class UpdateFeedTest extends AggregatorTestBase {
+  /**
+   * Creates a feed and attempts to update it.
+   */
+  public function testUpdateFeed() {
+    $remaining_fields = array('title[0][value]', 'url[0][value]', '');
+    foreach ($remaining_fields as $same_field) {
+      $feed = $this->createFeed();
+
+      // Get new feed data array and modify newly created feed.
+      $edit = $this->getFeedEditArray();
+      // Change refresh value.
+      $edit['refresh'] = 1800;
+      if (isset($feed->{$same_field}->value)) {
+        $edit[$same_field] = $feed->{$same_field}->value;
+      }
+      $this->drupalPostForm('aggregator/sources/' . $feed->id() . '/configure', $edit, t('Save'));
+      $this->assertRaw(t('The feed %name has been updated.', array('%name' => $edit['title[0][value]'])), format_string('The feed %name has been updated.', array('%name' => $edit['title[0][value]'])));
+
+      // Check feed data.
+      $this->assertUrl($feed->url('canonical', ['absolute' => TRUE]));
+      $this->assertTrue($this->uniqueFeed($edit['title[0][value]'], $edit['url[0][value]']), 'The feed is unique.');
+
+      // Check feed source.
+      $this->drupalGet('aggregator/sources/' . $feed->id());
+      $this->assertResponse(200, 'Feed source exists.');
+      $this->assertText($edit['title[0][value]'], 'Page title');
+
+      // Set correct title so deleteFeed() will work.
+      $feed->title = $edit['title[0][value]'];
+
+      // Delete feed.
+      $this->deleteFeed($feed);
+    }
+  }
+}

core/modules/aggregator/src/Tests/Views/AggregatorFeedViewsFieldAccessTest.php

@@ -0,0 +1,52 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\aggregator\Tests\Views\AggregatorFeedViewsFieldAccessTest.
+ */
+
+namespace Drupal\aggregator\Tests\Views;
+
+use Drupal\aggregator\Entity\Feed;
+use Drupal\views\Tests\Handler\FieldFieldAccessTestBase;
+
+/**
+ * Tests base field access in Views for the aggregator_feed entity.
+ *
+ * @group aggregator
+ */
+class AggregatorFeedViewsFieldAccessTest extends FieldFieldAccessTestBase {
+
+  /**
+   * {@inheritdoc}
+   */
+  public static $modules = ['aggregator', 'entity_test', 'options'];
+
+  /**
+   * {@inheritdoc}
+   */
+  protected function setUp($import_test_views = TRUE) {
+    parent::setUp($import_test_views);
+
+    $this->installEntitySchema('aggregator_feed');
+  }
+
+  /**
+   * Checks access for aggregator_feed fields.
+   */
+  public function testAggregatorFeedFields() {
+    $feed = Feed::create([
+      'title' => 'Drupal org',
+      'url' => 'https://www.drupal.org/rss.xml',
+      'link' => 'https://www.drupal.org/rss.xml',
+    ]);
+    $feed->save();
+
+    // @todo Expand the test coverage in https://www.drupal.org/node/2464635
+
+    // $this->assertFieldAccess('aggregator_feed', 'title', $feed->label());
+    $this->assertFieldAccess('aggregator_feed', 'langcode', $feed->language()->getName());
+    $this->assertFieldAccess('aggregator_feed', 'url', $feed->getUrl());
+  }
+
+}

core/modules/aggregator/src/Tests/Views/AggregatorItemViewsFieldAccessTest.php

@@ -0,0 +1,60 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\aggregator\Tests\Views\AggregatorItemViewsFieldAccessTest.
+ */
+
+namespace Drupal\aggregator\Tests\Views;
+
+use Drupal\aggregator\Entity\Feed;
+use Drupal\aggregator\Entity\Item;
+use Drupal\views\Tests\Handler\FieldFieldAccessTestBase;
+
+/**
+ * Tests base field access in Views for the aggregator_item entity.
+ *
+ * @group aggregator
+ */
+class AggregatorItemViewsFieldAccessTest extends FieldFieldAccessTestBase {
+
+  /**
+   * {@inheritdoc}
+   */
+  public static $modules = ['aggregator', 'entity_test', 'options'];
+
+  /**
+   * {@inheritdoc}
+   */
+  protected function setUp($import_test_views = TRUE) {
+    parent::setUp($import_test_views);
+
+    $this->installEntitySchema('aggregator_feed');
+    $this->installEntitySchema('aggregator_item');
+  }
+
+  /**
+   * Checks access for aggregator_item fields.
+   */
+  public function testAggregatorItemFields() {
+    $feed = Feed::create([
+      'title' => 'Drupal org',
+      'url' => 'https://www.drupal.org/rss.xml',
+    ]);
+    $feed->save();
+    $item = Item::create([
+      'title' => 'Test title',
+      'fid' => $feed->id(),
+      'description' => 'Test description',
+    ]);
+
+    $item->save();
+
+    // @todo Expand the test coverage in https://www.drupal.org/node/2464635
+
+    $this->assertFieldAccess('aggregator_item', 'title', $item->getTitle());
+    $this->assertFieldAccess('aggregator_item', 'langcode', $item->language()->getName());
+    $this->assertFieldAccess('aggregator_item', 'description', $item->getDescription());
+  }
+
+}

core/modules/aggregator/src/Tests/Views/IntegrationTest.php

@@ -0,0 +1,125 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\aggregator\Tests\Views\IntegrationTest.
+ */
+
+namespace Drupal\aggregator\Tests\Views;
+
+use Drupal\Core\Url;
+use Drupal\views\Views;
+use Drupal\views\Tests\ViewTestData;
+use Drupal\views\Tests\ViewUnitTestBase;
+
+/**
+ * Tests basic integration of views data from the aggregator module.
+ *
+ * @group aggregator
+ */
+class IntegrationTest extends ViewUnitTestBase {
+
+  /**
+   * Modules to install.
+   *
+   * @var array
+   */
+  public static $modules = array('aggregator', 'aggregator_test_views', 'system', 'field', 'options', 'user');
+
+  /**
+   * Views used by this test.
+   *
+   * @var array
+   */
+  public static $testViews = array('test_aggregator_items');
+
+  /**
+   * The entity storage for aggregator items.
+   *
+   * @var \Drupal\aggregator\ItemStorage
+   */
+  protected $itemStorage;
+
+  /**
+   * The entity storage for aggregator feeds.
+   *
+   * @var \Drupal\aggregator\FeedStorage
+   */
+  protected $feedStorage;
+
+  /**
+   * {@inheritdoc}
+   */
+  protected function setUp() {
+    parent::setUp();
+
+    $this->installEntitySchema('aggregator_item');
+    $this->installEntitySchema('aggregator_feed');
+
+    ViewTestData::createTestViews(get_class($this), array('aggregator_test_views'));
+
+    $this->itemStorage = $this->container->get('entity.manager')->getStorage('aggregator_item');
+    $this->feedStorage = $this->container->get('entity.manager')->getStorage('aggregator_feed');
+  }
+
+  /**
+   * Tests basic aggregator_item view.
+   */
+  public function testAggregatorItemView() {
+    $feed = $this->feedStorage->create(array(
+      'title' => $this->randomMachineName(),
+      'url' => 'https://www.drupal.org/',
+      'refresh' => 900,
+      'checked' => 123543535,
+      'description' => $this->randomMachineName(),
+    ));
+    $feed->save();
+
+    $items = array();
+    $expected = array();
+    for ($i = 0; $i < 10; $i++) {
+      $values = array();
+      $values['fid'] = $feed->id();
+      $values['timestamp'] = mt_rand(REQUEST_TIME - 10, REQUEST_TIME + 10);
+      $values['title'] = $this->randomMachineName();
+      $values['description'] = $this->randomMachineName();
+      // Add a image to ensure that the sanitizing can be tested below.
+      $values['author'] = $this->randomMachineName() . '<img src="http://example.com/example.png" \>"';
+      $values['link'] = 'https://www.drupal.org/node/' . mt_rand(1000, 10000);
+      $values['guid'] = $this->randomString();
+
+      $aggregator_item = $this->itemStorage->create($values);
+      $aggregator_item->save();
+      $items[$aggregator_item->id()] = $aggregator_item;
+
+      $values['iid'] = $aggregator_item->id();
+      $expected[] = $values;
+    }
+
+    $view = Views::getView('test_aggregator_items');
+    $this->executeView($view);
+
+    $column_map = array(
+      'iid' => 'iid',
+      'title' => 'title',
+      'aggregator_item_timestamp' => 'timestamp',
+      'description' => 'description',
+      'aggregator_item_author' => 'author',
+    );
+    $this->assertIdenticalResultset($view, $expected, $column_map);
+
+    // Ensure that the rendering of the linked title works as expected.
+    foreach ($view->result as $row) {
+      $iid = $view->field['iid']->getValue($row);
+      $expected_link = \Drupal::l($items[$iid]->getTitle(), Url::fromUri($items[$iid]->getLink(), ['absolute' => TRUE]));
+      $this->assertEqual($view->field['title']->advancedRender($row), $expected_link, 'Ensure the right link is generated');
+
+      $expected_author = aggregator_filter_xss($items[$iid]->getAuthor());
+      $this->assertEqual($view->field['author']->advancedRender($row), $expected_author, 'Ensure the author got filtered');
+
+      $expected_description = aggregator_filter_xss($items[$iid]->getDescription());
+      $this->assertEqual($view->field['description']->advancedRender($row), $expected_description, 'Ensure the author got filtered');
+    }
+  }
+
+}