Create a subject

{
  "topic": "org.eclipse.ditto/the_policy_id/policies/commands/modify",
  "headers": {
    "correlation-id": "<command-correlation-id>"
  },
  "path": "/entries/the_label/subjects/google:the_subjectid",
  "value": {
    "type": "yourSubjectTypeDescription"
  }
}

{
  "topic": "org.eclipse.ditto/the_policy_id/policies/commands/modify",
  "headers": {
    "correlation-id": "<preserved-command-correlation-id>"
  },
  "path": "/entries/the_label/subjects/google:the_subjectid",
  "status": 204
}