Move into nested docroot

web/core/modules/hal/src/Encoder/JsonEncoder.php

@@ -0,0 +1,35 @@
+<?php
+
+namespace Drupal\hal\Encoder;
+
+use Symfony\Component\Serializer\Encoder\JsonEncoder as SymfonyJsonEncoder;
+
+/**
+ * Encodes HAL data in JSON.
+ *
+ * Simply respond to hal_json format requests using the JSON encoder.
+ */
+class JsonEncoder extends SymfonyJsonEncoder {
+
+  /**
+   * The formats that this Encoder supports.
+   *
+   * @var string
+   */
+  protected $format = 'hal_json';
+
+  /**
+   * {@inheritdoc}
+   */
+  public function supportsEncoding($format) {
+    return $format == $this->format;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function supportsDecoding($format) {
+    return $format == $this->format;
+  }
+
+}

web/core/modules/hal/src/EventSubscriber/ExceptionHalJsonSubscriber.php

@@ -0,0 +1,19 @@
+<?php
+
+namespace Drupal\hal\EventSubscriber;
+
+use Drupal\Core\EventSubscriber\ExceptionJsonSubscriber;
+
+/**
+ * Handle HAL JSON exceptions the same as JSON exceptions.
+ */
+class ExceptionHalJsonSubscriber extends ExceptionJsonSubscriber {
+
+  /**
+   * {@inheritdoc}
+   */
+  protected function getHandledFormats() {
+    return ['hal_json'];
+  }
+
+}

web/core/modules/hal/src/HalServiceProvider.php

@@ -0,0 +1,22 @@
+<?php
+
+namespace Drupal\hal;
+
+use Drupal\Core\DependencyInjection\ContainerBuilder;
+use Drupal\Core\DependencyInjection\ServiceModifierInterface;
+
+/**
+ * Adds hal+json as known format.
+ */
+class HalServiceProvider implements ServiceModifierInterface {
+
+  /**
+   * {@inheritdoc}
+   */
+  public function alter(ContainerBuilder $container) {
+    if ($container->has('http_middleware.negotiation') && is_a($container->getDefinition('http_middleware.negotiation')->getClass(), '\Drupal\Core\StackMiddleware\NegotiationMiddleware', TRUE)) {
+      $container->getDefinition('http_middleware.negotiation')->addMethodCall('registerFormat', ['hal_json', ['application/hal+json']]);
+    }
+  }
+
+}

web/core/modules/hal/src/Normalizer/ContentEntityNormalizer.php

@@ -0,0 +1,262 @@
+<?php
+
+namespace Drupal\hal\Normalizer;
+
+use Drupal\Component\Utility\NestedArray;
+use Drupal\Core\Entity\EntityInterface;
+use Drupal\Core\Entity\EntityManagerInterface;
+use Drupal\Core\Extension\ModuleHandlerInterface;
+use Drupal\rest\LinkManager\LinkManagerInterface;
+use Symfony\Component\Serializer\Exception\UnexpectedValueException;
+
+/**
+ * Converts the Drupal entity object structure to a HAL array structure.
+ */
+class ContentEntityNormalizer extends NormalizerBase {
+
+  /**
+   * The interface or class that this Normalizer supports.
+   *
+   * @var string
+   */
+  protected $supportedInterfaceOrClass = 'Drupal\Core\Entity\ContentEntityInterface';
+
+  /**
+   * The hypermedia link manager.
+   *
+   * @var \Drupal\rest\LinkManager\LinkManagerInterface
+   */
+  protected $linkManager;
+
+  /**
+   * The entity manager.
+   *
+   * @var \Drupal\Core\Entity\EntityManagerInterface
+   */
+  protected $entityManager;
+
+  /**
+   * The module handler.
+   *
+   * @var \Drupal\Core\Extension\ModuleHandlerInterface
+   */
+  protected $moduleHandler;
+
+
+  /**
+   * Constructs an ContentEntityNormalizer object.
+   *
+   * @param \Drupal\rest\LinkManager\LinkManagerInterface $link_manager
+   *   The hypermedia link manager.
+   */
+  public function __construct(LinkManagerInterface $link_manager, EntityManagerInterface $entity_manager, ModuleHandlerInterface $module_handler) {
+    $this->linkManager = $link_manager;
+    $this->entityManager = $entity_manager;
+    $this->moduleHandler = $module_handler;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function normalize($entity, $format = NULL, array $context = array()) {
+    $context += array(
+      'account' => NULL,
+      'included_fields' => NULL,
+    );
+
+    // Create the array of normalized fields, starting with the URI.
+    /** @var $entity \Drupal\Core\Entity\ContentEntityInterface */
+    $normalized = array(
+      '_links' => array(
+        'self' => array(
+          'href' => $this->getEntityUri($entity),
+        ),
+        'type' => array(
+          'href' => $this->linkManager->getTypeUri($entity->getEntityTypeId(), $entity->bundle(), $context),
+        ),
+      ),
+    );
+
+    // If the fields to use were specified, only output those field values.
+    if (isset($context['included_fields'])) {
+      $fields = array();
+      foreach ($context['included_fields'] as $field_name) {
+        $fields[] = $entity->get($field_name);
+      }
+    }
+    else {
+      $fields = $entity->getFields();
+    }
+    foreach ($fields as $field) {
+      // Continue if the current user does not have access to view this field.
+      if (!$field->access('view', $context['account'])) {
+        continue;
+      }
+
+      $normalized_property = $this->serializer->normalize($field, $format, $context);
+      $normalized = NestedArray::mergeDeep($normalized, $normalized_property);
+    }
+
+    return $normalized;
+  }
+
+  /**
+   * Implements \Symfony\Component\Serializer\Normalizer\DenormalizerInterface::denormalize().
+   *
+   * @param array $data
+   *   Entity data to restore.
+   * @param string $class
+   *   Unused, entity_create() is used to instantiate entity objects.
+   * @param string $format
+   *   Format the given data was extracted from.
+   * @param array $context
+   *   Options available to the denormalizer. Keys that can be used:
+   *   - request_method: if set to "patch" the denormalization will clear out
+   *     all default values for entity fields before applying $data to the
+   *     entity.
+   *
+   * @return \Drupal\Core\Entity\EntityInterface
+   *   An unserialized entity object containing the data in $data.
+   *
+   * @throws \Symfony\Component\Serializer\Exception\UnexpectedValueException
+   */
+  public function denormalize($data, $class, $format = NULL, array $context = array()) {
+    // Get type, necessary for determining which bundle to create.
+    if (!isset($data['_links']['type'])) {
+      throw new UnexpectedValueException('The type link relation must be specified.');
+    }
+
+    // Create the entity.
+    $typed_data_ids = $this->getTypedDataIds($data['_links']['type'], $context);
+    $entity_type = $this->entityManager->getDefinition($typed_data_ids['entity_type']);
+    $default_langcode_key = $entity_type->getKey('default_langcode');
+    $langcode_key = $entity_type->getKey('langcode');
+    $values = array();
+
+    // Figure out the language to use.
+    if (isset($data[$default_langcode_key])) {
+      // Find the field item for which the default_lancode value is set to 1 and
+      // set the langcode the right default language.
+      foreach ($data[$default_langcode_key] as $item) {
+        if (!empty($item['value']) && isset($item['lang'])) {
+          $values[$langcode_key] = $item['lang'];
+          break;
+        }
+      }
+      // Remove the default langcode so it does not get iterated over below.
+      unset($data[$default_langcode_key]);
+    }
+
+    if ($entity_type->hasKey('bundle')) {
+      $bundle_key = $entity_type->getKey('bundle');
+      $values[$bundle_key] = $typed_data_ids['bundle'];
+      // Unset the bundle key from data, if it's there.
+      unset($data[$bundle_key]);
+    }
+
+    $entity = $this->entityManager->getStorage($typed_data_ids['entity_type'])->create($values);
+
+    // Remove links from data array.
+    unset($data['_links']);
+    // Get embedded resources and remove from data array.
+    $embedded = array();
+    if (isset($data['_embedded'])) {
+      $embedded = $data['_embedded'];
+      unset($data['_embedded']);
+    }
+
+    // Flatten the embedded values.
+    foreach ($embedded as $relation => $field) {
+      $field_ids = $this->linkManager->getRelationInternalIds($relation);
+      if (!empty($field_ids)) {
+        $field_name = $field_ids['field_name'];
+        $data[$field_name] = $field;
+      }
+    }
+
+    // Pass the names of the fields whose values can be merged.
+    $entity->_restSubmittedFields = array_keys($data);
+
+    // Iterate through remaining items in data array. These should all
+    // correspond to fields.
+    foreach ($data as $field_name => $field_data) {
+      $items = $entity->get($field_name);
+      // Remove any values that were set as a part of entity creation (e.g
+      // uuid). If the incoming field data is set to an empty array, this will
+      // also have the effect of emptying the field in REST module.
+      $items->setValue(array());
+      if ($field_data) {
+        // Denormalize the field data into the FieldItemList object.
+        $context['target_instance'] = $items;
+        $this->serializer->denormalize($field_data, get_class($items), $format, $context);
+      }
+    }
+
+    return $entity;
+  }
+
+  /**
+   * Constructs the entity URI.
+   *
+   * @param \Drupal\Core\Entity\EntityInterface $entity
+   *   The entity.
+   * @return string
+   *   The entity URI.
+   */
+  protected function getEntityUri(EntityInterface $entity) {
+    // Some entity types don't provide a canonical link template, at least call
+    // out to ->url().
+    if ($entity->isNew() || !$entity->hasLinkTemplate('canonical')) {
+      return $entity->url('canonical', []);
+    }
+    $url = $entity->urlInfo('canonical', ['absolute' => TRUE]);
+    return $url->setRouteParameter('_format', 'hal_json')->toString();
+  }
+
+  /**
+   * Gets the typed data IDs for a type URI.
+   *
+   * @param array $types
+   *   The type array(s) (value of the 'type' attribute of the incoming data).
+   * @param array $context
+   *   Context from the normalizer/serializer operation.
+   *
+   * @return array
+   *   The typed data IDs.
+   */
+  protected function getTypedDataIds($types, $context = array()) {
+    // The 'type' can potentially contain an array of type objects. By default,
+    // Drupal only uses a single type in serializing, but allows for multiple
+    // types when deserializing.
+    if (isset($types['href'])) {
+      $types = array($types);
+    }
+
+    if (empty($types)) {
+      throw new UnexpectedValueException('No entity type(s) specified');
+    }
+
+    foreach ($types as $type) {
+      if (!isset($type['href'])) {
+        throw new UnexpectedValueException('Type must contain an \'href\' attribute.');
+      }
+
+      $type_uri = $type['href'];
+
+      // Check whether the URI corresponds to a known type on this site. Break
+      // once one does.
+      if ($typed_data_ids = $this->linkManager->getTypeInternalIds($type['href'], $context)) {
+        break;
+      }
+    }
+
+    // If none of the URIs correspond to an entity type on this site, no entity
+    // can be created. Throw an exception.
+    if (empty($typed_data_ids)) {
+      throw new UnexpectedValueException(sprintf('Type %s does not correspond to an entity on this site.', $type_uri));
+    }
+
+    return $typed_data_ids;
+  }
+
+}

web/core/modules/hal/src/Normalizer/EntityReferenceItemNormalizer.php

@@ -0,0 +1,122 @@
+<?php
+
+namespace Drupal\hal\Normalizer;
+
+use Drupal\Core\Entity\FieldableEntityInterface;
+use Drupal\rest\LinkManager\LinkManagerInterface;
+use Drupal\serialization\EntityResolver\EntityResolverInterface;
+use Drupal\serialization\EntityResolver\UuidReferenceInterface;
+
+/**
+ * Converts the Drupal entity reference item object to HAL array structure.
+ */
+class EntityReferenceItemNormalizer extends FieldItemNormalizer implements UuidReferenceInterface {
+
+  /**
+   * The interface or class that this Normalizer supports.
+   *
+   * @var string
+   */
+  protected $supportedInterfaceOrClass = 'Drupal\Core\Field\Plugin\Field\FieldType\EntityReferenceItem';
+
+  /**
+   * The hypermedia link manager.
+   *
+   * @var \Drupal\rest\LinkManager\LinkManagerInterface
+   */
+  protected $linkManager;
+
+  /**
+   * The entity resolver.
+   *
+   * @var \Drupal\serialization\EntityResolver\EntityResolverInterface
+   */
+  protected $entityResolver;
+
+  /**
+   * Constructs an EntityReferenceItemNormalizer object.
+   *
+   * @param \Drupal\rest\LinkManager\LinkManagerInterface $link_manager
+   *   The hypermedia link manager.
+   * @param \Drupal\serialization\EntityResolver\EntityResolverInterface $entity_Resolver
+   *   The entity resolver.
+   */
+  public function __construct(LinkManagerInterface $link_manager, EntityResolverInterface $entity_Resolver) {
+    $this->linkManager = $link_manager;
+    $this->entityResolver = $entity_Resolver;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function normalize($field_item, $format = NULL, array $context = array()) {
+    /** @var $field_item \Drupal\Core\Field\FieldItemInterface */
+    $target_entity = $field_item->get('entity')->getValue();
+
+    // If this is not a content entity, let the parent implementation handle it,
+    // only content entities are supported as embedded resources.
+    if (!($target_entity instanceof FieldableEntityInterface)) {
+      return parent::normalize($field_item, $format, $context);
+    }
+
+    // If the parent entity passed in a langcode, unset it before normalizing
+    // the target entity. Otherwise, untranslatable fields of the target entity
+    // will include the langcode.
+    $langcode = isset($context['langcode']) ? $context['langcode'] : NULL;
+    unset($context['langcode']);
+    $context['included_fields'] = array('uuid');
+
+    // Normalize the target entity.
+    $embedded = $this->serializer->normalize($target_entity, $format, $context);
+    $link = $embedded['_links']['self'];
+    // If the field is translatable, add the langcode to the link relation
+    // object. This does not indicate the language of the target entity.
+    if ($langcode) {
+      $embedded['lang'] = $link['lang'] = $langcode;
+    }
+
+    // The returned structure will be recursively merged into the normalized
+    // entity so that the items are properly added to the _links and _embedded
+    // objects.
+    $field_name = $field_item->getParent()->getName();
+    $entity = $field_item->getEntity();
+    $field_uri = $this->linkManager->getRelationUri($entity->getEntityTypeId(), $entity->bundle(), $field_name, $context);
+    return array(
+      '_links' => array(
+        $field_uri => array($link),
+      ),
+      '_embedded' => array(
+        $field_uri => array($embedded),
+      ),
+    );
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  protected function constructValue($data, $context) {
+    $field_item = $context['target_instance'];
+    $field_definition = $field_item->getFieldDefinition();
+    $target_type = $field_definition->getSetting('target_type');
+    $id = $this->entityResolver->resolve($this, $data, $target_type);
+    if (isset($id)) {
+      return array('target_id' => $id);
+    }
+    return NULL;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function getUuid($data) {
+    if (isset($data['uuid'])) {
+      $uuid = $data['uuid'];
+      // The value may be a nested array like $uuid[0]['value'].
+      if (is_array($uuid) && isset($uuid[0]['value'])) {
+        $uuid = $uuid[0]['value'];
+      }
+      return $uuid;
+    }
+  }
+
+}

web/core/modules/hal/src/Normalizer/FieldItemNormalizer.php

@@ -0,0 +1,111 @@
+<?php
+
+namespace Drupal\hal\Normalizer;
+
+use Drupal\Core\Field\FieldItemInterface;
+use Symfony\Component\Serializer\Exception\InvalidArgumentException;
+
+/**
+ * Converts the Drupal field item object structure to HAL array structure.
+ */
+class FieldItemNormalizer extends NormalizerBase {
+
+  /**
+   * The interface or class that this Normalizer supports.
+   *
+   * @var string
+   */
+  protected $supportedInterfaceOrClass = 'Drupal\Core\Field\FieldItemInterface';
+
+  /**
+   * {@inheritdoc}
+   */
+  public function normalize($field_item, $format = NULL, array $context = array()) {
+    $values = $field_item->toArray();
+    if (isset($context['langcode'])) {
+      $values['lang'] = $context['langcode'];
+    }
+
+    // The values are wrapped in an array, and then wrapped in another array
+    // keyed by field name so that field items can be merged by the
+    // FieldNormalizer. This is necessary for the EntityReferenceItemNormalizer
+    // to be able to place values in the '_links' array.
+    $field = $field_item->getParent();
+    return array(
+      $field->getName() => array($values),
+    );
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function denormalize($data, $class, $format = NULL, array $context = array()) {
+    if (!isset($context['target_instance'])) {
+      throw new InvalidArgumentException('$context[\'target_instance\'] must be set to denormalize with the FieldItemNormalizer');
+    }
+    if ($context['target_instance']->getParent() == NULL) {
+      throw new InvalidArgumentException('The field item passed in via $context[\'target_instance\'] must have a parent set.');
+    }
+
+    $field_item = $context['target_instance'];
+
+    // If this field is translatable, we need to create a translated instance.
+    if (isset($data['lang'])) {
+      $langcode = $data['lang'];
+      unset($data['lang']);
+      $field_definition = $field_item->getFieldDefinition();
+      if ($field_definition->isTranslatable()) {
+        $field_item = $this->createTranslatedInstance($field_item, $langcode);
+      }
+    }
+
+    $field_item->setValue($this->constructValue($data, $context));
+    return $field_item;
+  }
+
+  /**
+   * Build the field item value using the incoming data.
+   *
+   * @param $data
+   *   The incoming data for this field item.
+   * @param $context
+   *   The context passed into the Normalizer.
+   *
+   * @return mixed
+   *   The value to use in Entity::setValue().
+   */
+  protected function constructValue($data, $context) {
+    return $data;
+  }
+
+  /**
+   * Get a translated version of the field item instance.
+   *
+   * To indicate that a field item applies to one translation of an entity and
+   * not another, the property path must originate with a translation of the
+   * entity. This is the reason for using target_instances, from which the
+   * property path can be traversed up to the root.
+   *
+   * @param \Drupal\Core\Field\FieldItemInterface $field_item
+   *   The untranslated field item instance.
+   * @param $langcode
+   *   The langcode.
+   *
+   * @return \Drupal\Core\Field\FieldItemInterface
+   *   The translated field item instance.
+   */
+  protected function createTranslatedInstance(FieldItemInterface $item, $langcode) {
+    // Remove the untranslated item that was created for the default language
+    // by FieldNormalizer::denormalize().
+    $items = $item->getParent();
+    $delta = $item->getName();
+    unset($items[$delta]);
+
+    // Instead, create a new item for the entity in the requested language.
+    $entity = $item->getEntity();
+    $entity_translation = $entity->hasTranslation($langcode) ? $entity->getTranslation($langcode) : $entity->addTranslation($langcode);
+    $field_name = $item->getFieldDefinition()->getName();
+    return $entity_translation->get($field_name)->appendItem();
+  }
+
+}

web/core/modules/hal/src/Normalizer/FieldNormalizer.php

@@ -0,0 +1,104 @@
+<?php
+
+namespace Drupal\hal\Normalizer;
+
+use Drupal\Component\Utility\NestedArray;
+use Symfony\Component\Serializer\Exception\InvalidArgumentException;
+
+/**
+ * Converts the Drupal field structure to HAL array structure.
+ */
+class FieldNormalizer extends NormalizerBase {
+
+  /**
+   * The interface or class that this Normalizer supports.
+   *
+   * @var string
+   */
+  protected $supportedInterfaceOrClass = 'Drupal\Core\Field\FieldItemListInterface';
+
+  /**
+   * {@inheritdoc}
+   */
+  public function normalize($field, $format = NULL, array $context = array()) {
+    $normalized_field_items = array();
+
+    // Get the field definition.
+    $entity = $field->getEntity();
+    $field_name = $field->getName();
+    $field_definition = $field->getFieldDefinition();
+
+    // If this field is not translatable, it can simply be normalized without
+    // separating it into different translations.
+    if (!$field_definition->isTranslatable()) {
+      $normalized_field_items = $this->normalizeFieldItems($field, $format, $context);
+    }
+    // Otherwise, the languages have to be extracted from the entity and passed
+    // in to the field item normalizer in the context. The langcode is appended
+    // to the field item values.
+    else {
+      foreach ($entity->getTranslationLanguages() as $language) {
+        $context['langcode'] = $language->getId();
+        $translation = $entity->getTranslation($language->getId());
+        $translated_field = $translation->get($field_name);
+        $normalized_field_items = array_merge($normalized_field_items, $this->normalizeFieldItems($translated_field, $format, $context));
+      }
+    }
+
+    // Merge deep so that links set in entity reference normalizers are merged
+    // into the links property.
+    $normalized = NestedArray::mergeDeepArray($normalized_field_items);
+    return $normalized;
+  }
+
+
+  /**
+   * {@inheritdoc}
+   */
+  public function denormalize($data, $class, $format = NULL, array $context = array()) {
+    if (!isset($context['target_instance'])) {
+      throw new InvalidArgumentException('$context[\'target_instance\'] must be set to denormalize with the FieldNormalizer');
+    }
+    if ($context['target_instance']->getParent() == NULL) {
+      throw new InvalidArgumentException('The field passed in via $context[\'target_instance\'] must have a parent set.');
+    }
+
+    $items = $context['target_instance'];
+    $item_class = $items->getItemDefinition()->getClass();
+    foreach ($data as $item_data) {
+      // Create a new item and pass it as the target for the unserialization of
+      // $item_data. Note: if $item_data is about a different language than the
+      // default, FieldItemNormalizer::denormalize() will dismiss this item and
+      // create a new one for the right language.
+      $context['target_instance'] = $items->appendItem();
+      $this->serializer->denormalize($item_data, $item_class, $format, $context);
+    }
+
+    return $items;
+
+  }
+
+  /**
+   * Helper function to normalize field items.
+   *
+   * @param \Drupal\Core\Field\FieldItemListInterface $field
+   *   The field object.
+   * @param string $format
+   *   The format.
+   * @param array $context
+   *   The context array.
+   *
+   * @return array
+   *   The array of normalized field items.
+   */
+  protected function normalizeFieldItems($field, $format, $context) {
+    $normalized_field_items = array();
+    if (!$field->isEmpty()) {
+      foreach ($field as $field_item) {
+        $normalized_field_items[] = $this->serializer->normalize($field_item, $format, $context);
+      }
+    }
+    return $normalized_field_items;
+  }
+
+}

web/core/modules/hal/src/Normalizer/FileEntityNormalizer.php

@@ -0,0 +1,70 @@
+<?php
+
+namespace Drupal\hal\Normalizer;
+
+use Drupal\Core\Entity\EntityManagerInterface;
+use Drupal\Core\Extension\ModuleHandlerInterface;
+use Drupal\rest\LinkManager\LinkManagerInterface;
+use GuzzleHttp\ClientInterface;
+
+/**
+ * Converts the Drupal entity object structure to a HAL array structure.
+ */
+class FileEntityNormalizer extends ContentEntityNormalizer {
+
+  /**
+   * The interface or class that this Normalizer supports.
+   *
+   * @var string
+   */
+  protected $supportedInterfaceOrClass = 'Drupal\file\FileInterface';
+
+  /**
+   * The HTTP client.
+   *
+   * @var \GuzzleHttp\ClientInterface
+   */
+  protected $httpClient;
+
+  /**
+   * Constructs a FileEntityNormalizer object.
+   *
+   * @param \Drupal\Core\Entity\EntityManagerInterface $entity_manager
+   *   The entity manager.
+   * @param \GuzzleHttp\ClientInterface $http_client
+   *   The HTTP Client.
+   * @param \Drupal\rest\LinkManager\LinkManagerInterface $link_manager
+   *   The hypermedia link manager.
+   * @param \Drupal\Core\Extension\ModuleHandlerInterface $module_handler
+   *   The module handler.
+   */
+  public function __construct(EntityManagerInterface $entity_manager, ClientInterface $http_client, LinkManagerInterface $link_manager, ModuleHandlerInterface $module_handler) {
+    parent::__construct($link_manager, $entity_manager, $module_handler);
+
+    $this->httpClient = $http_client;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function normalize($entity, $format = NULL, array $context = array()) {
+    $data = parent::normalize($entity, $format, $context);
+    // Replace the file url with a full url for the file.
+    $data['uri'][0]['value'] = $this->getEntityUri($entity);
+
+    return $data;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function denormalize($data, $class, $format = NULL, array $context = array()) {
+    $file_data = (string) $this->httpClient->get($data['uri'][0]['value'])->getBody();
+
+    $path = 'temporary://' . drupal_basename($data['uri'][0]['value']);
+    $data['uri'] = file_unmanaged_save_data($file_data, $path);
+
+    return $this->entityManager->getStorage('file')->create($data);
+  }
+
+}

web/core/modules/hal/src/Normalizer/NormalizerBase.php

@@ -0,0 +1,45 @@
+<?php
+
+namespace Drupal\hal\Normalizer;
+
+use Drupal\serialization\Normalizer\NormalizerBase as SerializationNormalizerBase;
+use Symfony\Component\Serializer\Normalizer\DenormalizerInterface;
+
+/**
+ * Base class for Normalizers.
+ */
+abstract class NormalizerBase extends SerializationNormalizerBase implements DenormalizerInterface {
+
+  /**
+   * The formats that the Normalizer can handle.
+   *
+   * @var array
+   */
+  protected $formats = array('hal_json');
+
+  /**
+   * {@inheritdoc}
+   */
+  public function supportsNormalization($data, $format = NULL) {
+    return in_array($format, $this->formats) && parent::supportsNormalization($data, $format);
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function supportsDenormalization($data, $type, $format = NULL) {
+    if (in_array($format, $this->formats) && (class_exists($this->supportedInterfaceOrClass) || interface_exists($this->supportedInterfaceOrClass))) {
+      $target = new \ReflectionClass($type);
+      $supported = new \ReflectionClass($this->supportedInterfaceOrClass);
+      if ($supported->isInterface()) {
+        return $target->implementsInterface($this->supportedInterfaceOrClass);
+      }
+      else {
+        return ($target->getName() == $this->supportedInterfaceOrClass || $target->isSubclassOf($this->supportedInterfaceOrClass));
+      }
+    }
+
+    return FALSE;
+  }
+
+}

web/core/modules/hal/src/Tests/FileDenormalizeTest.php

@@ -0,0 +1,75 @@
+<?php
+
+namespace Drupal\hal\Tests;
+
+use Drupal\file\Entity\File;
+use Drupal\simpletest\WebTestBase;
+
+/**
+ * Tests that file entities can be denormalized in HAL.
+ *
+ * @group hal
+ * @see \Drupal\hal\Normalizer\FileEntityNormalizer
+ */
+class FileDenormalizeTest extends WebTestBase {
+
+  /**
+   * Modules to enable.
+   *
+   * @var array
+   */
+  public static $modules = array('hal', 'file', 'node');
+
+  /**
+   * Tests file entity denormalization.
+   */
+  public function testFileDenormalize() {
+    $file_params = array(
+      'filename' => 'test_1.txt',
+      'uri' => 'public://test_1.txt',
+      'filemime' => 'text/plain',
+      'status' => FILE_STATUS_PERMANENT,
+    );
+    // Create a new file entity.
+    $file = File::create($file_params);
+    file_put_contents($file->getFileUri(), 'hello world');
+    $file->save();
+
+    $serializer = \Drupal::service('serializer');
+    $normalized_data = $serializer->normalize($file, 'hal_json');
+    $denormalized = $serializer->denormalize($normalized_data, 'Drupal\file\Entity\File', 'hal_json');
+
+    $this->assertTrue($denormalized instanceof File, 'A File instance was created.');
+
+    $this->assertIdentical('temporary://' . $file->getFilename(), $denormalized->getFileUri(), 'The expected file URI was found.');
+    $this->assertTrue(file_exists($denormalized->getFileUri()), 'The temporary file was found.');
+
+    $this->assertIdentical($file->uuid(), $denormalized->uuid(), 'The expected UUID was found');
+    $this->assertIdentical($file->getMimeType(), $denormalized->getMimeType(), 'The expected MIME type was found.');
+    $this->assertIdentical($file->getFilename(), $denormalized->getFilename(), 'The expected filename was found.');
+    $this->assertTrue($denormalized->isPermanent(), 'The file has a permanent status.');
+
+    // Try to denormalize with the file uri only.
+    $file_name = 'test_2.txt';
+    $file_path = 'public://' . $file_name;
+
+    file_put_contents($file_path, 'hello world');
+    $file_uri = file_create_url($file_path);
+
+    $data = array(
+      'uri' => array(
+        array('value' => $file_uri),
+      ),
+    );
+
+    $denormalized = $serializer->denormalize($data, 'Drupal\file\Entity\File', 'hal_json');
+
+    $this->assertIdentical('temporary://' . $file_name, $denormalized->getFileUri(), 'The expected file URI was found.');
+    $this->assertTrue(file_exists($denormalized->getFileUri()), 'The temporary file was found.');
+
+    $this->assertIdentical('text/plain', $denormalized->getMimeType(), 'The expected MIME type was found.');
+    $this->assertIdentical($file_name, $denormalized->getFilename(), 'The expected filename was found.');
+    $this->assertFalse($denormalized->isPermanent(), 'The file has a permanent status.');
+  }
+
+}