5.8.8. Security Constraints for Collection Attributes

If an entity that is returned by the REST API has a collection attribute and entities in the collection are restricted by any constraint then a system attribute __securityToken may be returned in the result JSON. When you send such entity to REST API methods for update you have to specify the __securityToken property (the one you got on entity read) in the JSON object. Otherwise, the collection property may be saved incorrectly.

Example:

{
  "id": "fa430b56-ceb2-150f-6a85-12c691908bd1",
  "number": "OR-000001",
  "items": [
    {
      "id": "82e6e6d2-be97-c81c-c58d-5e2760ae095a",
      "description": "Item 1"
    },
    {
      "id": "988a8cb5-d61a-e493-c401-f717dd9a2d66",
      "description": "Item 2"
    }
  ],
  "__securityToken": "0NXc6bQh+vZuXE4Fsk4mJX4QnhS3lOBfxzUniltchpxPfi1rZ5htEmekfV60sbEuWUykbDoY+rCxdhzORaYQNQ=="
}