swagger-model-fragment.json

"User": {
  "type": "object",
  "required": ["email", "roles"],
  "properties": {
    "email": {
      "type": "string"
    },
    "firstName": {
      "type": "string"
    },
    "lastName": {
      "type": "string",
      "description": "User's surname"
    },
    "roles": {
      "type": "array",
      "items": {
        "type": "string",
        "enum": ["USER","ADMIN"]
      }
    }
  }
}