{
  "$schema": "https://json-schema.org/draft/2020-12/schema",
  "type": "object",
  "properties": {
    "id": {
      "type": "string",
      "pattern": "^[0-9]{1,20}$"
    },
    "username": {
      "type": "string"
    },
    "name": {
      "type": "string"
    }
  },
  "required": ["id", "username", "name"]
}