json_schema: {
    "type": "object",
    "title": "Artist schema",
    "$schema": "http://json-schema.org/draft-04/schema",
    "properties": {
      "id": {
        "type": "string",
        "args": {
          "primary_key": true
        }
      },
      "name": {
        "type": "string"
      },
      "description": {
        "type": "string"
      },
      "tracks": {
        "type": "object",
        "args": {
          "document": "Track",
          "ondelete": "NULLIFY",
          "backref_name": "artist",
          "backref_ondelete": "NULLIFY"
        }
      },
      "events": {
        "type": "object",
        "args": {
          "document": "Event",
          "ondelete": "NULLIFY",
          "backref_name": "artist",
          "backref_ondelete": "NULLIFY"
        }
      }
    },
    "required": [
      "id",
      "name"
    ]
  }
  