diff --git a/core/modules/field/tests/src/Kernel/EntityReference/EntityReferenceItemTest.php b/core/modules/field/tests/src/Kernel/EntityReference/EntityReferenceItemTest.php
index 2d98de66d3..6dce67b45f 100644
--- a/core/modules/field/tests/src/Kernel/EntityReference/EntityReferenceItemTest.php
+++ b/core/modules/field/tests/src/Kernel/EntityReference/EntityReferenceItemTest.php
@@ -524,7 +524,6 @@ public function testAutocreateValidation() {
     $file = File::create([
       'filename' => $filename,
       'status' => 0,
-      'uid' => 1,
     ]);
 
     $entity = EntityTest::create([
diff --git a/core/modules/file/src/Entity/File.php b/core/modules/file/src/Entity/File.php
index b8c130728c..a68b9bae9b 100644
--- a/core/modules/file/src/Entity/File.php
+++ b/core/modules/file/src/Entity/File.php
@@ -234,7 +234,6 @@ public static function baseFieldDefinitions(EntityTypeInterface $entity_type) {
     $fields['uid'] = BaseFieldDefinition::create('entity_reference')
       ->setLabel(t('User ID'))
       ->setDescription(t('The user ID of the file.'))
-      ->setDefaultValueCallback('\Drupal\file\Entity\File::getCurrentUserId')
       ->setSetting('target_type', 'user');
 
     $fields['filename'] = BaseFieldDefinition::create('string')
@@ -275,16 +274,4 @@ public static function baseFieldDefinitions(EntityTypeInterface $entity_type) {
     return $fields;
   }
 
-  /**
-   * Default value callback for 'uid' base field definition.
-   *
-   * @see \Drupal\file\Entity\File::baseFieldDefinitions::baseFieldDefinitions().
-   *
-   * @return array
-   *   An array of default values.
-   */
-  public static function getCurrentUserId() {
-    return array(\Drupal::currentUser()->id());
-  }
-
 }
diff --git a/core/modules/file/src/Plugin/rest/resource/FileUploadResource.php b/core/modules/file/src/Plugin/rest/resource/FileUploadResource.php
index 1177f9a961..83286804af 100644
--- a/core/modules/file/src/Plugin/rest/resource/FileUploadResource.php
+++ b/core/modules/file/src/Plugin/rest/resource/FileUploadResource.php
@@ -2,7 +2,6 @@
 
 namespace Drupal\file\Plugin\rest\resource;
 
-use Drupal\Component\Plugin\DependentPluginInterface;
 use Drupal\Component\Utility\Bytes;
 use Drupal\Core\Field\FieldDefinitionInterface;
 use Drupal\Core\Session\AccountInterface;
@@ -38,9 +37,11 @@
  *   }
  * )
  */
-class FileUploadResource extends ResourceBase implements DependentPluginInterface {
+class FileUploadResource extends ResourceBase {
 
-  use EntityResourceValidationTrait;
+  use EntityResourceValidationTrait {
+    validate as resourceValidate;
+  }
 
   /**
    * @var \Drupal\Core\File\FileSystem
@@ -68,6 +69,11 @@ class FileUploadResource extends ResourceBase implements DependentPluginInterfac
   protected $mimeTypeGuesser;
 
   /**
+   * @var \Drupal\Core\Utility\Token|Token
+   */
+  protected $token;
+
+  /**
    * Constructs a FileUploadResource instance.
    *
    * @param array $configuration
@@ -88,14 +94,17 @@ class FileUploadResource extends ResourceBase implements DependentPluginInterfac
    *   The currently authenticated user.
    * @param \Symfony\Component\HttpFoundation\File\MimeType\MimeTypeGuesserInterface $mime_type_guesser
    *   The MIME type guesser.
+   * @param \Drupal\Core\Utility\Token $token
+   *   The token replacement instance.
    *
    */
-  public function __construct(array $configuration, $plugin_id, $plugin_definition,$serializer_formats, LoggerInterface $logger, FileSystem $file_system, EntityFieldManagerInterface $entity_field_manager, AccountInterface $current_user, MimeTypeGuesserInterface $mime_type_guesser) {
+  public function __construct(array $configuration, $plugin_id, $plugin_definition,$serializer_formats, LoggerInterface $logger, FileSystem $file_system, EntityFieldManagerInterface $entity_field_manager, AccountInterface $current_user, MimeTypeGuesserInterface $mime_type_guesser, Token $token) {
     parent::__construct($configuration, $plugin_id, $plugin_definition, $serializer_formats, $logger);
     $this->fileSystem = $file_system;
     $this->entityFieldManager = $entity_field_manager;
     $this->currentUser = $current_user;
     $this->mimeTypeGuesser = $mime_type_guesser;
+    $this->token = $token;
   }
 
   /**
@@ -111,42 +120,22 @@ public static function create(ContainerInterface $container, array $configuratio
       $container->get('file_system'),
       $container->get('entity_field.manager'),
       $container->get('current_user'),
-      $container->get('file.mime_type.guesser')
+      $container->get('file.mime_type.guesser').
+      $container->get('token')
     );
   }
 
   /**
-   * {@inheritdoc}
-   */
-  public function calculateDependencies() {
-    return [
-      'module' => ['file']
-    ];
-  }
-
-  /**
    * Creates a file from endpoint.
    *
    * @param \Symfony\Component\HttpFoundation\Request $request
    * @param \Drupal\file\FileInterface $file
    */
   public function post(Request $request, $entity_type_id, $bundle, $field_name) {
-    $this->validateOctetStream($request);
+    $this->validateOctetStreamContentType($request);
     // @todo Validate for file name too.
 
-    $field_definitions = $this->entityFieldManager->getFieldDefinitions($entity_type_id, $bundle);
-
-    if (!isset($field_definitions[$field_name])) {
-      throw new BadRequestHttpException(sprintf('Field "%s" does not exist', $field_name));
-    }
-
-    // @todo check the definition is a file field.
-    $field_definition = $field_definitions[$field_name];
-
-    // Check access.
-    if (!$field_definition->access('create')) {
-      throw new AccessDeniedException(sprintf('Access denied for field "%s"', $field_name));
-    }
+    $field_definition = $this->validateAndLoadFieldDefinition($entity_type_id, $bundle, $field_name);
 
     $destination = $this->getUploadLocation($field_definition->getFieldStorageDefinition()->getSettings());
 
@@ -182,10 +171,7 @@ public function post(Request $request, $entity_type_id, $bundle, $field_name) {
     $values['filemime'] = $this->mimeTypeGuesser->guess($values['filename']);
     $file = File::create($values);
 
-    $this->validateFile($file, $field_definition);
-
-    $this->validate($file);
-
+    $this->validate($file, $field_definition);
 
     $file->save();
 
@@ -227,6 +213,39 @@ protected function streamUploadData($destination_uri) {
   }
 
   /**
+   * Validates and loads a field definition instance.
+   *
+   * @param string $entity_type_id
+   *   The entity type ID the field is attached to.
+   * @param string $bundle
+   *   The bundle the field is attached to.
+   * @param string $field_name
+   *   The field name.
+   *
+   * @return \Drupal\Core\Field\FieldDefinitionInterface
+   *
+   * @throws \Symfony\Component\HttpKernel\Exception\BadRequestHttpException
+   * @throws \Symfony\Component\HttpFoundation\File\Exception\AccessDeniedException
+   */
+  protected function validateAndLoadFieldDefinition($entity_type_id, $bundle, $field_name) {
+    $field_definitions = $this->entityFieldManager->getFieldDefinitions($entity_type_id, $bundle);
+
+    if (!isset($field_definitions[$field_name])) {
+      throw new BadRequestHttpException(sprintf('Field "%s" does not exist', $field_name));
+    }
+
+    // @todo check the definition is a file field.
+    $field_definition = $field_definitions[$field_name];
+
+    // Check access.
+    if (!$field_definition->access('create')) {
+      throw new AccessDeniedException(sprintf('Access denied for field "%s"', $field_name));
+    }
+
+    return $field_definition;
+  }
+
+  /**
    * Validates the Content-Type header for the request.
    *
    * @param \Symfony\Component\HttpKernel\Request $request
@@ -234,7 +253,7 @@ protected function streamUploadData($destination_uri) {
    *
    * @throws \Symfony\Component\HttpKernel\Exception\UnsupportedMediaTypeHttpException
    */
-  protected function validateOctetStream(Request $request) {
+  protected function validateOctetStreamContentType(Request $request) {
     if ($request->headers->get('Content-Type') !== 'application/octet-stream') {
       throw new UnsupportedMediaTypeHttpException('The "application/octet-stream" content type must be used to send binary file data');
     }
@@ -250,7 +269,9 @@ protected function validateOctetStream(Request $request) {
    *
    * @throws \Symfony\Component\HttpKernel\Exception\UnprocessableEntityHttpException
    */
-  protected function validateFile(FileInterface $file, FieldDefinitionInterface $field_definition) {
+  protected function validate(FileInterface $file, FieldDefinitionInterface $field_definition) {
+    $this->resourceValidate($file);
+
     // Validate the file based on the field definition configuration.
     $errors = file_validate($file, $this->getUploadValidators($field_definition));
 
@@ -277,7 +298,7 @@ protected function getUploadLocation(array $settings) {
 
     // Replace tokens. As the tokens might contain HTML we convert it to plain
     // text.
-    $destination = PlainTextOutput::renderFromHtml(\Drupal::token()->replace($destination, $data));
+    $destination = PlainTextOutput::renderFromHtml($this->token->replace($destination, []));
     return $settings['uri_scheme'] . '://' . $destination;
   }