Drupal 8 : serialize typed data into JSON - Among other rad things that you can do via the type data api in drupal 8. the following example shows how to interact with typed data with the core Serialize service for serializing and deserializing lists of URI data types items.

Drupal 8 : serialize typed data into JSON.md

Drupal 8 : serialize typed data into JSON

from: Typed Data API overview (drupal.org)

  // Serialize Typed Data into JSON.
  $listDefinition = \Drupal::typedDataManager()->createListDataDefinition('uri');
  $list = \Drupal::typedDataManager()->create($listDefinition, ['http://example.com', 'http://drupal.org']);
  $serializer = \Drupal::service('serializer');
  echo $serializer->serialize($list, 'json');
  // ["http://example.com", "http://drupal.org"]

  // Deserialize JSON into Typed Data.
  $encoded = json_encode(["http://example.com", "http://drupal.org"]);
  $myList = $serializer->deserialize($encoded, 'Drupal\Core\TypedData\Plugin\DataType\Uri', 'json', ['plugin_id' => 'uri']);
  echo $myList->get(0)->getValue();
  // 'http://example.com'